Functional high-quality batteries!
KEY SPECS · MOLICEL INR-21700-P42A
SOURCE [1]- SIZE
- Ø21.55 × 70.15 mm
- max.
- CAPACITY
- 4,200 mAh typ.
- 4,000 mAh min.
- CURRENT
- 45 A
- continuous
- condition not stated by manufacturer
- TEMPERATURE
- −40 to 60 °C
- discharge
- charge 0 to 45 °C
MOLICEL · 21700 · INR-21700-P42A
A 21700 cell: 4,200 mAh typical and 4,000 mAh minimum capacity, a 45 A continuous discharge current and a 4.2 A standard charge current, as Molicel’s data sheet prints them, with no condition beside any of them [2]. Below: each rating with the conditions the documents do print, Molicel’s own curves digitized, and what we calculated from them, so you can check each number.
CAPACITY4,200 mAhtypical; 4,000 mAh minimum; no condition printed [2]
CONTINUOUS DISCHARGE45 Ano condition printed [2]; a maximum in [1]; cell surface ≤ 85 °C [1] §7.2.3 2)
STANDARD CHARGE4.2 Ano condition printed [2]; 8.4 A maximum, about 15 to 45 °C cell surface only [1] §4.14, fig 5.5
ENERGY15.5 Whtypical, no condition or basis printed [2]; minimum 14.7 Wh [2] or 14.40 Wh [3], fig 1.5
AC IMPEDANCE10 mΩtypical, “AC (1 KHz)” [2]; DC 16 mΩ typical, “DC (10A/1s)” [2]
MASS70 gmaximum [1][2]
A bare cell: a component for protected packs and devices built for it. Not for vaping. Charge on a lithium-ion (Li-ion) charger that stops at 4.2 V, at the standard 4.2 A or less, from 0 to 45 °C [2].
01SPEC PLATE
Every rating, with its condition.
Two Molicel technical documents describe this cell. The one-page product data sheet [2], “Version: 1.7”, sets the ratings, and the page follows it wherever the two documents overlap; it prints no date (its PDF file was created 2023-06-14), and it is linked above. The approval sheet [1], “Cell Specifications of INR-21700-P42A”, Rev. 0.2, dated 2018-08-17 (printed “8/17/2018”), called the 2018 specification below, is older and adds what the data sheet doesn’t print: minimums by current and temperature, cycle life, storage, safety tests and a charge-current window. Our copy was issued to a Molicel customer, and every page is marked confidential, so we quote it but don’t post it. Where the two differ, the row shows both (section 08 below). Then come figures we read from the data sheet’s charts, our arithmetic, and facts from the safety data sheet (SDS) [3] and the UN38.3 transport test report [4]. Each row names its source or shows its formula.
| SPECIFICATION | VALUE | CONDITION · SOURCE |
|---|---|---|
| RATED · MANUFACTURER copied from data sheet [2] and the 2018 specification [1] | ||
| MODEL CODE | INR-21700-P42A | as printed [1][2][4]; “INR21700-P42A” [3]; [1] §2.2 prints “INR-21700A-P42A”; designation INR22/71 [1] §2.3 |
| CAPACITY, TYPICAL | 4,200 mAh | “Typical” “4200 mAh”; no condition printed [2]; [1] prints no typical capacity |
| CAPACITY, MINIMUM | 4,000 mAh | “Minimum” “4000 mAh”; no condition printed [2] |
| RATED CAPACITY, 2018 SPECIFICATION | 4.0 Ah | “4.0Ah (Minimum)”, 4,000 mAh: “Rated discharge capacity after rated charge.”, rated discharge “Constant 0.84A discharge until 2.5V at 23 oC.” [1] §4 items 2–3 |
| ENERGY, TYPICAL · MINIMUM | 15.5 · 14.7 Wh | [2]; no condition or basis printed; [1] prints no Wh; the SDS’s figures and 3.6 V × capacity are in the second plate and in fig 1.5 |
| NOMINAL VOLTAGE | 3.6 V | “Nominal” [2]; “Mean voltage during rated discharge after rated charge.” [1] §4 item 4 |
| CHARGE VOLTAGE | 4.2 V | “Charge” [2]; “4.20 ± 0.05V”, end of charge voltage [1] §4 item 7 |
| DISCHARGE CUT-OFF | 2.5 V | “Discharge” [2]; “Discharge voltage for determination of rated capacity.” [1] §4 item 8 |
| STANDARD CHARGE | 4.2 A | “Charge Current” “Standard” “4.2 A”; no condition printed [2]; rated charge “Limiting 4.2A and constant 4.2V charge for 1.5h or 50mA at 23 oC.” [1] §4 item 1 |
| CHARGE TIME, STANDARD | 1.5 h | “1.5 hr” [2]; “90 min”, “Rated charge.” [1] §4 item 9 |
| MAXIMUM CHARGE, 2018 SPECIFICATION | 8.4 A | “Maximum charging current”, “See Section 4.14”: 8.4 A only from about 15 to about 45 °C cell surface temperature, 4.2 A from −20 to about 15 °C and from about 45 to 60 °C (fig 5.5; the two step temperatures are read from the chart) [1] §4 item 10; [2] prints no maximum (section 08 below) |
| CONTINUOUS DISCHARGE | 45 A | “Discharge Current” “Continuous” “45 A”; no condition printed [2]; [1] prints the same 45 A as the “Maximum discharging current”, remark “Cycle life is reduced at high rates.” [1] §4 item 10; no pulse rating printed |
| CELL SURFACE, LIMIT | 85 °C | “The cell surface temperature must not exceed 85°C.” [1] §7.2.3 2) |
| THERMAL CUT-OFF, RECOMMENDED | 75 °C | “Recommended thermal cut-off of 75°C at high rates.” [1] §7.2.3 2) |
| CHARGE TEMPERATURE | 0 to 45 °C | “Temperature” “Charge” “0°C to 45°C”, basis not printed [2]; the 2018 specification prints “-20~60 oC” [1] §4 item 11 and, in a caution, “0 oC to 60 oC” [1] §7.3.2 3) (section 08 below) |
| DISCHARGE TEMPERATURE | −40 to 60 °C | “-40°C to 60°C”, basis not printed [2]; “-40~60 oC” [1] §4 item 11; “At a temperature of –40oC or less, the cell will show a significant decrease in discharge capacity.” [1] §7.2.3 2); “Consult E-One Moli Energy if you plan to discharge the cells at temperature less than –30oC.” [1] §7.3.3 2) |
| AC IMPEDANCE, TYPICAL | 10 mΩ | “Typical Impedance”, “AC (1 KHz)” [2]; state of charge and temperature not printed; [1] prints “≤ 15mΩ”, “Fresh cell measured by AC impedance at 1kHz” [1] §4 item 6 |
| DC IMPEDANCE, TYPICAL | 16 mΩ | “Typical Impedance”, “DC (10A/1s)” [2]; state of charge and temperature not printed |
| ENERGY DENSITY, VOLUMETRIC | 615 Wh/l | “Volumetric” [2]; basis not printed |
| ENERGY DENSITY, GRAVIMETRIC | 230 Wh/kg | “Gravimetric” [2]; basis not printed |
| SHIPPING VOLTAGE | ≥ 3.45 V | “Nominal approximate state of charge ≤ 30%.” [1] §4 item 5 |
| STORAGE, SHIPPED CELL | < 35 °C | “Storage temperature for shipping cell”; “Recommended temperature less than 23 oC for long term storage.” [1] §4 item 12 |
| SHELF LIFE | 1 year | “See Section 5.4.” [1] §4 item 13 |
| DIAMETER | 21.55 mm | “21.55 mm (Max)” [2]; “21.40 ± 0.15 mm” [1] §2.4.2 |
| HEIGHT | 70.15 mm | “70.15 mm (Max)” [2]; “70.00 ± 0.15 mm” [1] §2.4.2 |
| MASS | 70 g | “70 g (Max)” [2]; “70.0 (Max)” [1] §2.4.2 |
| SHAPE · CAN | Cylindrical · steel | shape [1][2]; can [2] |
| POSITIVE END | Flat | as drawn in [2] and [1] §2.4.3; no top style is named |
| MINIMUMS · 2018 SPECIFICATION electrical performance, cycle life and storage, as printed [1] | ||
| MINIMUM AT 0.84 A | 4,000 mAh | to 2.5 V after rated charge, 23 °C; printed “≥4.00Ah” [1] §5.2 |
| MINIMUM AT 4.2 A | 3,900 mAh | to 2.5 V after rated charge, 23 °C; printed “≥3.90Ah” [1] §5.2 |
| MINIMUM AT 10 A | 3,900 mAh | to 2.5 V after rated charge, 23 °C; printed “≥3.90Ah” [1] §5.2 |
| MINIMUM AT 45 °C | 4,000 mAh | 4.2 A to 2.5 V, after rated charge at 23 °C; printed “≥4.00Ah” [1] §5.2 |
| MINIMUM AT 0 °C | 3,400 mAh | 4.2 A to 2.5 V, after rated charge at 23 °C; printed “≥3.40Ah” [1] §5.2 |
| MINIMUM AT −20 °C | 3,300 mAh | 4.2 A to 2.5 V, after rated charge at 23 °C; printed “≥3.30Ah” [1] §5.2 |
| MINIMUM AT −30 °C | 3,300 mAh | 4.2 A to 2.0 V, not 2.5 V, after rated charge at 23 °C; printed “≥3.30Ah” [1] §5.2 |
| CYCLE LIFE, 4.2 A | ≥ 80 % | after 500 cycles (“C500”): 4.2 A charge, 4.2 A discharge to 2.5 V (§5.1.4), 23 °C; “The % = (Ah / 3.90) x 100%” [1] §5.3 |
| CYCLE LIFE, 10 A | ≥ 80 % | after 500 cycles (“C500”): 4.2 A charge, 10 A discharge to 2.5 V (§5.1.5), 23 °C; “The % = (Ah / 3.90) x 100%” [1] §5.3 |
| STORAGE, 1 · 3 · 6 MONTHS | ≥ 18 · 15 · 10 % | 23 °C from 25 % charge, “25% SOC”; “The % = (Ah / 4.0) x 100%” [1] §5.4 |
| + Source: [1] E-One Moli Energy Corp., Approval Sheet, “Cell Specifications of INR-21700-P42A”, Doc # INR21700P42A-01, “Rev.: 0.2”, 8/17/2018 (as printed); on file; not posted: every page is marked “-- CONFIDENTIAL --” and “Proprietary of E-One Moli Energy Corp.”, so we quote it but don’t post it. Questions about its figures: call or text us + Source: [2] Molicel, Product Data Sheet, Model INR-21700-P42A, “Version: 1.7” (as printed; no date or document number printed); it carries no confidential marking and says “The information contained herein is for reference only and does not imply a performance guarantee or a product warranty.”; retrieved 2026-11-07 · Data sheet PDF + Source: [3] Molicel, Safety Data Sheet FSSF00058BJ, Molicel Rechargeable Lithium-ion cells and multi-cell battery packs; its version field prints BI; “Issue Date: January 10, 2025”; Table 6 lists INR21700-P42A; retrieved 2026-11-07 · SDS PDF + Source: [4] AnTek Certification Inc., Lithium Ion Battery Safety Testing Report TW1906114-001, INR-21700-P42A, to UN Manual of Tests and Criteria ST/SG/AC.10/11/Rev.6/Amend.1; test dates 2019-06-24 to 2019-07-11; issued 2019-07-12; retrieved 2026-11-07 · UN38.3 report PDF | ||
| SPECIFICATION | VALUE | CONDITION · SOURCE |
|---|---|---|
| READ FROM DATA-SHEET CHARTS digitized from the vector charts in [2], within about ±0.5 % of each axis | ||
| CAPACITY AT 0.84 A | 4,242 mAh | where the drawn curve ends, at 2.47 V; 23 °C [2] |
| CAPACITY AT 30 A | 4,098 mAh | where the drawn curve ends, at 2.49 V; 23 °C [2]; the highest current [2] charts (it draws no 45 A curve) |
| CAPACITY AT −20 °C | 3,851 mAh | 4.2 A after a CC-CV charge at 23 °C, where the drawn curve ends, at 2.49 V; temperature basis not printed [2] |
| CAPACITY AT −40 °C | 3,620 mAh | 4.2 A after a CC-CV charge at 23 °C, where the drawn curve ends, at 2.50 V; the curve first dips to about 2.54 V near 18 mAh, then recovers [2] |
| 4.2 A CHARGE, TRACE END | 81 min | CC-CV to 4.2 V, 23 °C; about 51 mA flowing there, at the printed “50mA cut” [2] |
| 8.4 A CHARGE TEST, TRACE END | 54 min | about 82 mA still flowing, above the printed 50 mA cut; a test current, not a rating of [2] |
| CYCLE 500 · 10 A | 85.6 % | 4.2 A charge, 10 A discharge, 23 °C; % basis not printed [2] |
| CYCLE 500 · 20 A | 87.2 % | 4.2 A charge, 20 A discharge, 23 °C; % basis not printed [2] |
| CALCULATED arithmetic on [1] and [2], shown so you can check it | ||
| 1C, OUR BASIS | 4.2 A | 4.2 Ah typical [2] ÷ 1 h; no P42A document prints a C-rate (“C500” in [1] means cycle 500) |
| CONTINUOUS DISCHARGE AS C-RATE | 10.71C | 45 A continuous discharge current, no condition printed [2], ÷ 4.2 A; [1] calls the same 45 A a maximum |
| STANDARD CHARGE AS C-RATE | 1C | 4.2 A standard, no condition printed [2], ÷ 4.2 A |
| MAXIMUM CHARGE [1] AS C-RATE | 2C | 8.4 A maximum, about 15 to 45 °C cell surface only [1] §4.14, ÷ 4.2 A |
| ENERGY, NOMINAL × CAPACITY | 15.12 · 14.40 Wh | 3.6 V × 4.2 Ah · 3.6 V × 4.0 Ah [2]; [2] prints 15.5 and 14.7 Wh |
| ENERGY AT 30 A | 13.46 Wh | ∫V dQ along the 30 A curve to its drawn end [2] |
| AVERAGE POWER AT 30 A | 98.6 W | 30 A × 3.285 V average of that curve (13.46 Wh ÷ 4,098 mAh) [2] |
| CYCLE LIFE IN mAh | 3,120 mAh | minimum after 500 cycles (“C500”): 80 % × 3.90 Ah, at 4.2 A and at 10 A [1] §5.3 |
| STORAGE IN mAh | 720 · 600 · 400 mAh | minimum after 1, 3, 6 months at 23 °C from 25 % charge: 18, 15, 10 % × 4.0 Ah, rounded half up [1] §5.4 |
| FROM THE SAFETY DATA SHEET (SDS) AND UN38.3 TRANSPORT TEST REPORT copied as printed from [3] and [4] | ||
| CHEMISTRY | Li-ion | [1][2] say lithium-ion only. The SDS’s ingredient table, written for all Molicel cells, lists a cathode that “Includes one or more of the following:” Lithium Cobaltite, Manganese, Nickel, Aluminum; “*Quantities may vary depending on cell or battery model.” [3] Table 3 |
| CAPACITY · SDS | 4.20 Ah | “4.20 Ah (4.00Ah Min)”, “Typical Capacity (Ah)” [3] Table 6 |
| ENERGY · SDS | 15.12 Wh | “15.12 Wh (14.40 Wh Min)”, “Watt Hour Rating (Wh) (Volts x Ah)” [3] Table 6 |
| LITHIUM CONTENT | 1.26 g | “Equivalent Lithium Content (g) (cell Ah x 0.3 x #cells)” [3] Table 6; that formula gives 1.26 g from 4.20 Ah (our arithmetic) |
| MASS · SDS | 70.0 g | as printed, basis not stated [3] Table 6 |
| TRANSPORT | UN3480 · Class 9 | “UN3480 or UN3481”: UN3481 when contained in or packed with equipment [3] §14; packing instructions: air “PI910, PI965, PI966 and PI967”, sea “P903, P908 or P910” [3] §14.8.5–14.8.6 |
| UN38.3 | TW1906114-001 | T1–T5, T6 impact and T8 “Passed”; T6 crush and T7 “N/A”; AnTek Certification Inc., issued 2019-07-12 [4] |
| SAFETY DATA SHEET | FSSF00058BJ | its version field prints BI; “Issue Date: January 10, 2025”; Table 6 lists INR21700-P42A [3] |
| + Source: [1] E-One Moli Energy Corp., Approval Sheet, “Cell Specifications of INR-21700-P42A”, Doc # INR21700P42A-01, “Rev.: 0.2”, 8/17/2018 (as printed); on file; not posted: every page is marked “-- CONFIDENTIAL --” and “Proprietary of E-One Moli Energy Corp.”, so we quote it but don’t post it. Questions about its figures: call or text us + Source: [2] Molicel, Product Data Sheet, Model INR-21700-P42A, “Version: 1.7” (as printed; no date or document number printed); it carries no confidential marking and says “The information contained herein is for reference only and does not imply a performance guarantee or a product warranty.”; retrieved 2026-11-07 · Data sheet PDF + Source: [3] Molicel, Safety Data Sheet FSSF00058BJ, Molicel Rechargeable Lithium-ion cells and multi-cell battery packs; its version field prints BI; “Issue Date: January 10, 2025”; Table 6 lists INR21700-P42A; retrieved 2026-11-07 · SDS PDF + Source: [4] AnTek Certification Inc., Lithium Ion Battery Safety Testing Report TW1906114-001, INR-21700-P42A, to UN Manual of Tests and Criteria ST/SG/AC.10/11/Rev.6/Amend.1; test dates 2019-06-24 to 2019-07-11; issued 2019-07-12; retrieved 2026-11-07 · UN38.3 report PDF | ||
RATED [1][2] · DIGITIZED [2]FIG 1.1
Voltage window
2.5 V3.6 V4.2 Vdischargenominalcharge
Black marks: the three cell voltages [2] prints, “Discharge”, “Nominal” and “Charge”; [1] prints the same three. Orange band: where the middle 80 % of capacity is delivered at 0.84 A, [1]’s rated discharge, 3.26–4.05 V, read from the 0.84 A curve digitized from [2].
RATED · [1][2]FIG 1.2
Current limits
Rated discharge 0.84 A · 0.2C · “Constant 0.84A discharge until 2.5V at 23 oC.” [1]
0.84 A
Standard charge 4.2 A · 1C · no condition printed [2]; [1]’s rated charge
4.2 A
Maximum charge, 2018 specification 8.4 A · 2C · about 15 to 45 °C cell surface only, fig 5.5 [1]
8.4 A
Continuous discharge 45 A · 10.71C · no condition printed [2]; a maximum in [1]
45 A
Currents as printed, in A, with the conditions printed beside them: the 45 A continuous discharge and the 4.2 A standard charge from the data sheet [2], which prints none for either; the 0.84 A rated discharge and the 8.4 A maximum charge, allowed only from about 15 to 45 °C cell surface temperature, from the 2018 specification [1]. C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h); no P42A document prints one. [1] §7.2.3 2) adds an 85 °C cell-surface limit and recommends a 75 °C thermal cut-off at high rates. No pulse rating is printed.
PRINTED IN [1][2]FIG 1.3
Temperature envelope
Discharge −40 to 60 °C [2]; “-40~60 oC” [1]
Charge 0 to 45 °C [2]
Charge, 2018 specification “-20~60 oC” [1] §4 item 11; marks: 8.4 A from about 15 to 45 °C cell surface, §4.14
Consult Molicel below “–30oC” [1] §7.3.3 2); “–40oC or less”: “significant decrease in discharge capacity” §7.2.3 2)
Recommended thermal cut-off 75 °C “at high rates” [1] §7.2.3 2)
Cell surface limit 85 °C, “must not exceed” [1] §7.2.3 2)
Temperature-chart test points [2], −40 to 60 °C
Operating ranges in °C. [2] prints “Temperature” with “0°C to 45°C” for charge and “-40°C to 60°C” for discharge, and doesn’t say whether these are ambient or cell temperatures. The 2018 specification [1] prints “-20~60 oC” for charge, which its own caution contradicts, “0 oC to 60 oC” (§7.3.2 3)), and allows its 8.4 A maximum only from about 15 to 45 °C cell surface temperature (§4.14; the steps are read from its chart, fig 5.5). Below −30 °C, [1] §7.3.3 2) says “Consult E-One Moli Energy if you plan to discharge the cells at temperature less than –30oC.” Last row: the test temperatures of the data sheet’s discharge-temperature chart, shown in section 04 below.
DOCUMENTS · [1]–[4]FIG 1.4
Capacity, as each document prints it
Data sheet [2], typical “4200 mAh”; no condition printed
4,200
Data sheet [2], minimum “4000 mAh”; no condition printed
4,000
2018 specification [1] “4.0Ah (Minimum)”: rated charge, then 0.84 A to 2.5 V at 23 °C
4,000
SDS [3] “4.20 Ah (4.00Ah Min)”
UN38.3 report [4] “3.6 Vdc, 4.2 Ah, 15.1 Wh”
4,200
0.84 A curve, digitized where the drawn curve ends, 2.47 V [2]
4,242
Each document’s capacity figure, as printed, on a 3,900–4,300 mAh scale; the axis doesn’t start at zero. Only [1] prints a condition: its rated charge, then a 0.84 A discharge to 2.5 V at 23 °C, for its 4.0 Ah minimum; [1] prints no typical capacity. Last row: where the data sheet’s 0.84 A curve ends, a chart reading, not a rating.
DOCUMENTS · [1]–[4]FIG 1.5
Energy, by document
Data sheet [2], typical no condition or basis printed
15.5
Data sheet [2], minimum no basis printed
14.7
SDS [3] “15.12 Wh (14.40 Wh Min)”, “(Volts x Ah)”
UN38.3 report [4] “3.6 Vdc, 4.2 Ah, 15.1 Wh”
15.1
3.6 V × capacity, calculated × 4.2 Ah = 15.12; × 4.0 Ah = 14.40 [2]
0.84 A curve, calculated ∫V dQ to the drawn end, 2.47 V [2]
15.58
30 A curve, calculated ∫V dQ to the drawn end, 2.49 V [2]
13.46
Energy figures in Wh on a 13.0–16.0 Wh scale; the axis doesn’t start at zero. The SDS [3] prints nominal voltage × capacity, “(Volts x Ah)”: 3.6 V × 4.2 Ah = 15.12 Wh, and 3.6 V × 4.0 Ah = 14.40 Wh for the minimum; the UN38.3 report [4] prints 15.1 Wh beside 3.6 Vdc and 4.2 Ah. [2]’s 15.5 and 14.7 Wh are higher, and [2] doesn’t print how it found them; our integration of its 0.84 A curve gives about 15.58 Wh.
02 · DISCHARGE
Discharge at 0.84 A and 30 A.
The lowest and highest currents the data sheet charts, digitized: 0.84 A is the 2018 specification’s rated discharge [1], and 30 A is the highest current [2] draws a curve for, below its 45 A continuous rating (no condition printed). At 0.84 A the drawn curve ends at 2.47 V after about 4,242 mAh. At 30 A the cell delivers about 4,098 mAh to 2.49 V; after 2,000 mAh delivered it sits 0.41 V below the 0.84 A curve.
0.84 A · 0.2C15.58 Whabout 4,242 mAh to 2.47 V · digitized from [2]; Wh calculated
30 A · 7.14C13.46 Whabout 4,098 mAh to 2.49 V, about 8.2 min · digitized from [2]; Wh and min calculated
DIGITIZED FROM [2]FIG 2.1
V
2.53.03.54.04.201,0002,0003,0004,0000.84 A · 0.2C30 A · 7.14C
Capacity, mAh
Data: digitized from [2] “Discharge Rate Characteristics” · 0.84 A and 30 A · “Charge: CC-CV, 4.2A, 4.2V, 50mA.” · “Discharge: Cut 0ff at 2.5V.” (printed with a zero) · “Temperature: 23oC.” · each curve ends at its last drawn point · C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h) · data tables under figs 3.1 and 3.2
03BY CURRENT
Capacity, energy and runtime, by current.
Five discharge currents from the data sheet, from 0.84 A to 30 A, beside the minimums the 2018 specification sets at three of them. The first two figures are the curves; the rest are arithmetic on them, with the formula under each. The data sheet draws no 45 A curve and charts no cell temperature.
DIGITIZED FROM [2]FIG 3.1
Discharge at 0.84, 4.2 and 10 A
0.84 A · 0.2C4.2 A · 1C10 A · 2.38C
V
2.53.03.54.001,0002,0003,0004,000
Capacity, mAh
Data: digitized from [2] “Discharge Rate Characteristics” · 0.84 A, 4.2 A, 10 A · “Charge: CC-CV, 4.2A, 4.2V, 50mA.” · “Discharge: Cut 0ff at 2.5V.” (printed with a zero) · “Temperature: 23oC.” · each curve ends at its last drawn point, 2.47–2.50 V · C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h) · orange: 0.84 A, the rated discharge [1]
DATA TABLE · FIG 3.1
| SERIES | V AT 100 mAh | 1,000 | 2,000 | 3,000 | 4,000 | END mAh | END V |
|---|---|---|---|---|---|---|---|
| 0.84 A · 0.2C | 4.11 | 3.95 | 3.72 | 3.53 | 3.07 | 4,242 | 2.47 |
| 4.2 A · 1C | 4.03 | 3.87 | 3.66 | 3.45 | 3.03 | 4,177 | 2.49 |
| 10 A · 2.38C | 3.91 | 3.77 | 3.55 | 3.35 | 2.89 | 4,149 | 2.50 |
DIGITIZED FROM [2]FIG 3.2
Discharge at 10, 20 and 30 A
10 A · 2.38C20 A · 4.76C30 A · 7.14C
V
2.53.03.54.001,0002,0003,0004,000
Capacity, mAh
Data: digitized from [2] “Discharge Rate Characteristics” · 10 A, 20 A, 30 A · “Charge: CC-CV, 4.2A, 4.2V, 50mA.” · “Discharge: Cut 0ff at 2.5V.” (printed with a zero) · “Temperature: 23oC.” · each curve ends at its last drawn point, 2.49–2.50 V · the 10 A curve’s end runs under the edge of the 20 A curve from about 4,127 mAh; a sliver stays visible, and both end at about 4,149 mAh, as drawn · no 45 A curve is drawn · C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h) · orange: 30 A, the highest current [2] charts
DATA TABLE · FIG 3.2
| SERIES | V AT 100 mAh | 1,000 | 2,000 | 3,000 | 4,000 | END mAh | END V |
|---|---|---|---|---|---|---|---|
| 10 A · 2.38C | 3.91 | 3.77 | 3.55 | 3.35 | 2.89 | 4,149 | 2.50 |
| 20 A · 4.76C | 3.75 | 3.64 | 3.43 | 3.23 | 2.81 | 4,149 | 2.49 |
| 30 A · 7.14C | 3.60 | 3.52 | 3.32 | 3.14 | 2.68 | 4,098 | 2.49 |
DIGITIZED [2] · PRINTED [1]FIG 3.3
Capacity delivered, by current
End of each digitized curve [2]Minimum, as printed in [1] §5.2
Black: capacity at the end of each curve in [2] “Discharge Rate Characteristics”, where each drawn line ends, at 2.47–2.50 V. Gray: the minimum [1] §5.2 sets at that current, “Discharge capacity to 2.5V after rated charge (4.1).”, at 23 °C. [1] prints no minimum at 20 or 30 A, and [2] draws no curve at its 45 A continuous rating (no condition printed). C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h).
DATA TABLE · FIG 3.3
| CURRENT | C-RATE, OUR BASIS | CURVE END mAh [2] | MINIMUM mAh [1] |
|---|---|---|---|
| 0.84 A | 0.2C | 4,242 | 4,000 |
| 4.2 A | 1C | 4,177 | 3,900 |
| 10 A | 2.38C | 4,149 | 3,900 |
| 20 A | 4.76C | 4,149 | not printed |
| 30 A | 7.14C | 4,098 | not printed |
| 45 A | 10.71C | no curve | not printed |
CALCULATED FROM [2]FIG 3.4
Energy delivered, by current
Energy = the area under each voltage–capacity curve (∫V dQ), digitized from [2] “Discharge Rate Characteristics”, to its drawn end. Orange: 30 A, the highest current [2] charts. Data-sheet figures for comparison: 15.5 Wh typical, 14.7 Wh minimum [2], with no basis printed.
CALCULATED FROM [2]FIG 3.5
Voltage sag, by current
after 500 mAhafter 2,000 mAhafter 3,500 mAh
V
2.83.23.64.00102030
Discharge current, A
Cell voltage after the same capacity delivered, read from each curve in [2]. At 2,000 mAh the 30 A curve sits 0.406 V below the 0.84 A curve: 0.406 V ÷ 29.16 A ≈ 13.9 mΩ (13.1–16.0 mΩ across the three depths). Effective resistance = (V at 0.84 A − V at 30 A) ÷ (30 − 0.84) A at the same capacity delivered; arithmetic, not a rating. [2] prints a typical DC impedance of 16 mΩ, “DC (10A/1s)”, and a typical AC impedance of 10 mΩ, “AC (1 KHz)”; [1] prints “≤ 15mΩ” at 1 kHz on a fresh cell. They aren’t the same quantity: a 1 kHz reading leaves out the slower voltage losses a long discharge includes, and [2] prints no state of charge or temperature for its “DC (10A/1s)” reading; the curves give 13.1–16.0 mΩ, at or below its 16 mΩ, and no document says why. The lines join the five currents [2] charts; nothing between them is printed.
DATA TABLE · FIG 3.5
| DEPTH | 0.84 A | 4.2 A | 10 A | 20 A | 30 A | mΩ, 0.84 → 30 A |
|---|---|---|---|---|---|---|
| 500 mAh | 4.050 | 3.970 | 3.863 | 3.714 | 3.583 | 16.0 |
| 2,000 mAh | 3.725 | 3.655 | 3.554 | 3.429 | 3.318 | 13.9 |
| 3,500 mAh | 3.409 | 3.347 | 3.238 | 3.126 | 3.026 | 13.1 |
CALCULATED FROM [2]FIG 3.6
Average power output, by current
Power = current × average voltage of each digitized curve in [2], over the whole discharge to its drawn end; the start of a discharge runs higher, the end lower. Power is taken from the unrounded average voltage. Orange: 30 A, the highest current [2] charts. No document prints a power rating.
CALCULATED FROM [2]FIG 3.7
Runtime at a constant current
Runtime = capacity delivered ÷ current, from the curves in [2]: from a full CC-CV charge, at 23 °C. A device whose average draw is below its peak current runs longer than the figure at that peak. Orange: 30 A, the highest current [2] charts. C-rates on our basis, 1C = 4.2 A (4.2 Ah typical [2] ÷ 1 h).
CALCULATED FROM [2]FIG 3.8
Estimated heat in the cell, by current
From the curves: I × (V on the 0.84 A curve − V at I)I² × 16 mΩ
Two estimates of heat generated inside one cell, averaged over the discharge. Orange: current × the average voltage gap to the 0.84 A curve, read from [2]. Gray: current² × the 16 mΩ typical DC impedance, “DC (10A/1s)” [2]. [2] draws no curve at its 45 A continuous rating (no condition printed), so that row has only the second estimate. [2] charts no cell temperature; [1] §7.2.3 2) limits the cell surface to 85 °C. In a pack, neighboring cells add their heat: plan cooling, and derate.
CALCULATED FROM [2]FIG 3.9
Energy against power
Wh
13141516251020501000.84 A4.2 A10 A20 A30 A
Average power, W (log scale)
Each point is one digitized curve from [2] “Discharge Rate Characteristics”: energy delivered against average power, power on a log scale. The line joins the five points; nothing between them is printed. Orange: 30 A, the highest current [2] charts.
DATA TABLE · FIG 3.9
| CURRENT | AVERAGE W | ENERGY Wh | RUNTIME |
|---|---|---|---|
| 0.84 A · 0.2C | 3.1 | 15.58 | 5 h 03 min |
| 4.2 A · 1C | 15.2 | 15.10 | 60 min |
| 10 A · 2.38C | 35.1 | 14.58 | 25 min |
| 20 A · 4.76C | 67.8 | 14.07 | 12 min |
| 30 A · 7.14C | 98.6 | 13.46 | 8.2 min |
04BY TEMPERATURE
Discharge, by temperature.
Seven test temperatures from −40 to 60 °C, digitized from the data sheet, all charged at 23 °C and discharged at 4.2 A to 2.5 V; every curve runs to about 2.5 V as printed. The chart doesn’t say whether these are ambient or cell temperatures. The 2018 specification sets minimums at 45, 0, −20 and −30 °C [1] §5.2.
DIGITIZED FROM [2]FIG 4.1
Discharge at 60, 45 and 23 °C
60 °C45 °C23 °C
V
2.53.03.54.001,0002,0003,0004,000
Capacity, mAh
Data: digitized from [2] “Discharge Temperature Characteristics” · “Charge: CC-CV, 4.2A, 4.2V, 50mA at 23 oC.” · “Discharge: 4.2A, Cut off at 2.5V.” · the 23, 45 and 60 °C curves run on top of one another in [2]; the 23 °C line is broken from about 3,660 to 4,010 mAh, where [2] draws it under the 45 and 60 °C curves · the 23 and 45 °C curves start at their first visible points, about 8 and 1 mAh: their first drawn points lie under later curves · orange: 23 °C, the same drawn path as the rate chart’s 4.2 A curve (fig 3.1) · the chart doesn’t say whether these are ambient or cell temperatures
DATA TABLE · FIG 4.1
| SERIES | V AT 100 mAh | 1,000 | 2,000 | 3,000 | 4,000 | END mAh | END V |
|---|---|---|---|---|---|---|---|
| 60 °C | 4.07 | 3.92 | 3.70 | 3.49 | 3.06 | 4,248 | 2.50 |
| 45 °C | 4.06 | 3.89 | 3.68 | 3.47 | 3.03 | 4,226 | 2.49 |
| 23 °C | 4.03 | 3.87 | 3.66 | 3.45 | hidden in [2] | 4,177 | 2.49 |
DIGITIZED FROM [2]FIG 4.2
Discharge at 23, 0 and −20 °C
23 °C0 °C−20 °C
V
2.53.03.54.001,0002,0003,0004,000
Capacity, mAh
Data: digitized from [2] “Discharge Temperature Characteristics” · “Charge: CC-CV, 4.2A, 4.2V, 50mA at 23 oC.” · “Discharge: 4.2A, Cut off at 2.5V.” · the 23 °C line is broken from about 3,660 to 4,010 mAh, where [2] draws it under the 45 and 60 °C curves (fig 4.1) · the 0 and −20 °C curves start at their first visible points: their first drawn points lie on the voltage axis under later curves · the chart doesn’t say whether these are ambient or cell temperatures
DATA TABLE · FIG 4.2
| SERIES | V AT 100 mAh | 1,000 | 2,000 | 3,000 | 4,000 | END mAh | END V |
|---|---|---|---|---|---|---|---|
| 23 °C | 4.03 | 3.87 | 3.66 | 3.45 | hidden in [2] | 4,177 | 2.49 |
| 0 °C | 3.84 | 3.78 | 3.57 | 3.37 | 2.69 | 4,032 | 2.49 |
| −20 °C | 3.52 | 3.63 | 3.42 | 3.20 | curve ended | 3,851 | 2.49 |
DIGITIZED FROM [2]FIG 4.3
Discharge at −20, −30 and −40 °C
−20 °C−30 °C−40 °C
V
2.53.03.54.001,0002,0003,0004,000
Capacity, mAh
Data: digitized from [2] “Discharge Temperature Characteristics” · “Charge: CC-CV, 4.2A, 4.2V, 50mA at 23 oC.” · “Discharge: 4.2A, Cut off at 2.5V.” · the three curves start at their first visible points: their first drawn points lie on the voltage axis under later curves · the −40 °C curve first dips to about 2.54 V near 18 mAh, then recovers · [1] §7.2.3 2): “At a temperature of –40oC or less, the cell will show a significant decrease in discharge capacity.” · the chart doesn’t say whether these are ambient or cell temperatures
DATA TABLE · FIG 4.3
| SERIES | V AT 100 mAh | 1,000 | 2,000 | 3,000 | 4,000 | END mAh | END V |
|---|---|---|---|---|---|---|---|
| −20 °C | 3.52 | 3.63 | 3.42 | 3.20 | curve ended | 3,851 | 2.49 |
| −30 °C | 3.25 | 3.49 | 3.27 | 3.01 | curve ended | 3,704 | 2.50 |
| −40 °C | 2.81 | 3.37 | 3.15 | 2.86 | curve ended | 3,620 | 2.50 |
DIGITIZED [2] · PRINTED [1]FIG 4.4
Capacity to the cut-off, by test temperature
Read from each curve [2]Minimum, as printed in [1] §5.2
Black: capacity where each temperature curve in [2] ends, at 2.49–2.50 V. Gray: the minimum [1] §5.2 sets at that temperature, at 4.2 A after a rated charge at 23 °C; at 23 °C, its 4.2 A minimum. [1]’s −30 °C minimum is to 2.0 V, below where the chart’s curves end; [1] prints no minimum at 60 or −40 °C. At −40 °C the curve first dips to about 2.54 V near 18 mAh, 0.04 V above the cut-off, then recovers.
DATA TABLE · FIG 4.4
| TEMPERATURE | CURVE END mAh [2] | END V | MINIMUM mAh [1] §5.2 |
|---|---|---|---|
| 60 °C | 4,248 | 2.50 | not printed |
| 45 °C | 4,226 | 2.49 | ≥ 4,000, 4.2 A to 2.5 V |
| 23 °C | 4,177 | 2.49 | ≥ 3,900, 4.2 A row, 23 °C (§5.2 item 1) |
| 0 °C | 4,032 | 2.49 | ≥ 3,400, 4.2 A to 2.5 V |
| −20 °C | 3,851 | 2.49 | ≥ 3,300, 4.2 A to 2.5 V |
| −30 °C | 3,704 | 2.50 | ≥ 3,300, 4.2 A to 2.0 V |
| −40 °C | 3,620 | 2.50 | not printed |
CALCULATED FROM [2]FIG 4.5
Average voltage, by test temperature
V
3.03.23.43.6−40−2002040603.103.233.383.543.613.623.64
Test temperature, °C
Average voltage = energy ÷ capacity for each digitized temperature curve in [2], from its first visible point to its end at about 2.5 V, so every curve is cut at the same voltage; the 23 °C figure uses its whole digitized path, including the stretch hidden under the warmer curves. The 23 °C sum starts at 8 mAh, its first visible point, so it reads 15.06 Wh; the same path from 0 mAh, the 4.2 A curve in fig 3.4, gives 15.10 Wh. Orange: 23 °C. Lower voltage at the same current means less power and more heat in the cell.
DATA TABLE · FIG 4.5
| TEMPERATURE | CURVE END mAh | ENERGY Wh | AVERAGE V |
|---|---|---|---|
| 60 °C | 4,248 | 15.46 | 3.64 |
| 45 °C | 4,226 | 15.31 | 3.62 |
| 23 °C | 4,177 | 15.06 | 3.61 |
| 0 °C | 4,032 | 14.26 | 3.54 |
| −20 °C | 3,851 | 13.03 | 3.38 |
| −30 °C | 3,704 | 11.98 | 3.23 |
| −40 °C | 3,620 | 11.21 | 3.10 |
05CHARGING
Charging: 4.2 A standard, from 0 to 45 °C.
The data sheet charts two charges, CC-CV to 4.2 V with a 50 mA cut at 23 °C: one at its 4.2 A standard current and an 8.4 A test [2]. Figs 5.1 to 5.3 are their traces; fig 5.4 adds up the charge each put in; fig 5.5 is the 2018 specification’s limit on charge current by cell surface temperature, [1] §4.14. The data sheet prints no maximum charge current. The 2018 specification’s 8.4 A maximum applies only from about 15 to 45 °C cell surface temperature [1] §4.14; this page follows the data sheet.
DIGITIZED FROM [2]FIG 5.1
Cell voltage while charging
4.2 A · 1C, standard8.4 A · 2C, test
V
2.83.23.64.04.20306090
Time, min
Data: digitized from [2] “Charge Characteristics” · “Charge:” “CC-CV Charge to 4.2V, 50mA cut at 23oC.” · legend “4.2A charge” (a solid line in [2]) and “8.4A charge” (dotted in [2], its dashes joined here) · the chart’s time axis is in hours; shown here in minutes · the 4.2 A traces end at 81 min with about 51 mA flowing, at the printed 50 mA cut; the 8.4 A traces end at about 54 min with about 82 mA still flowing, above it, and [2] doesn’t say why · 8.4 A is a test current: [2] prints only its 4.2 A standard charge current · both voltage traces start on the voltage axis in [2], at 2.69 and 2.82 V, and climb along it · the dotted 8.4 A line runs into the solid 4.2 A line at about 52 min
DATA TABLE · FIG 5.1
| CHARGE | 0 min | 15 min | 30 min | 45 min | 60 min | 75 min | 81 min |
|---|---|---|---|---|---|---|---|
| 4.2 A · 1C, standard | 2.69 V | 3.63 V | 3.82 V | 4.06 V | 4.20 V | 4.20 V | 4.20 V |
| 8.4 A · 2C, test | 2.82 V | 3.88 V | 4.20 V | 4.20 V | trace ended | trace ended | trace ended |
DIGITIZED FROM [2]FIG 5.2
Charge current
4.2 A · 1C, standard8.4 A · 2C, test
A
024680306090
Time, min
Data: digitized from [2] “Charge Characteristics” · “Charge:” “CC-CV Charge to 4.2V, 50mA cut at 23oC.” · line styles, time axis and trace ends as under fig 5.1 · the 8.4 A current starts to fall at about 24 min, before its voltage trace reaches 4.2 V at about 26 min, as drawn
DATA TABLE · FIG 5.2
| CHARGE | 0 min | 15 min | 30 min | 45 min | 60 min | 75 min | 81 min |
|---|---|---|---|---|---|---|---|
| 4.2 A · 1C, standard | 4.20 A | 4.20 A | 4.20 A | 4.20 A | 2.27 A | 0.15 A | 0.05 A |
| 8.4 A · 2C, test | 8.40 A | 8.40 A | 4.84 A | 0.40 A | trace ended | trace ended | trace ended |
DIGITIZED FROM [2]FIG 5.3
Charge returned, percent as printed
4.2 A · 1C, standard8.4 A · 2C, test
%
02550751000306090
Time, min
Data: digitized from [2] “Charge Characteristics” · “Charge:” “CC-CV Charge to 4.2V, 50mA cut at 23oC.” · line styles, time axis and trace ends as under fig 5.1 · [2] doesn’t print what 100 % is; each trace reaches 100.0 % only at its end: the 4.2 A trace at its last point, the 8.4 A trace at about 53.5 min, under a minute before its last point
DATA TABLE · FIG 5.3
| CHARGE | 0 min | 15 min | 30 min | 45 min | 60 min | 75 min | 81 min |
|---|---|---|---|---|---|---|---|
| 4.2 A · 1C, standard | 0 % | 24 % | 49 % | 73 % | 95 % | 99.7 % | 100.0 % |
| 8.4 A · 2C, test | 0 % | 48 % | 91 % | 99.6 % | trace ended | trace ended | trace ended |
CALCULATED FROM [2]FIG 5.4
Charge put in, mAh
4.2 A · 1C, standard8.4 A · 2C, test
mAh
01,0002,0003,0004,0000306090
Time, min
Charge put in = current × time, summed along each current trace digitized from [2] (fig 5.2). At 4.2 A the constant-current stage ends at about 54 min with 3,766 mAh put in; the trace’s end at 81 min brings the sum to about 4,308 mAh. At 8.4 A the constant-current stage ends at about 24 min with 3,342 mAh put in; its current trace sums to about 4,622 mAh by 54 min, about 310 mAh more than the 4.2 A charge, although it stops earlier, with about 82 mA still flowing. [2] doesn’t explain the difference, and its % traces print no basis (fig 5.3), so no mAh is read from them; read the 8.4 A total with care. Dotted line: 4,200 mAh typical [2].
DATA TABLE · FIG 5.4
| CHARGE | 1,000 mAh | 2,000 mAh | 3,000 mAh | 4,000 mAh | CONSTANT CURRENT ENDS | PUT IN BY THEN | SUM TO TRACE END |
|---|---|---|---|---|---|---|---|
| 4.2 A · 1C, standard | 14 min | 29 min | 43 min | 58 min | 54 min | 3,766 mAh | 4,308 mAh at 81 min |
| 8.4 A · 2C, test | 7 min | 14 min | 21 min | 30 min | 24 min | 3,342 mAh | 4,622 mAh at 54 min |
PRINTED IN [1] · STEPS READFIG 5.5
Maximum charge current, by cell surface temperature (2018)
“Specified operating region”, one boundary [1]
A
04.28.4−2002040608.4 A, about 15 to 45 °C4.2 A
Cell surface temperature, °C
Drawn from the printed figures, not digitized: [1] §4.14, “Maximum charge current versus cell surface temperature.”, chart “Charge Rate vs Temperature”, “Charge Voltage = 4.2 ± 0.05V”, legend “Specified operating region”. The chart prints its two levels as axis ticks, 4.2 and 8.4, and its line ends at −20 and 60 °C; [1] §4 item 10 prints “8.4A”, “See Section 4.14”. The two steps fall midway between labeled gridlines and are our readings, about 15 and about 45 °C. The data sheet [2], the newer document, prints no maximum charge current and a 0 to 45 °C charge range.
DATA TABLE · FIG 5.5
| CELL SURFACE TEMPERATURE | MAXIMUM CHARGE CURRENT, AS DRAWN |
|---|---|
| −20 to about 15 °C | 4.2 A |
| about 15 to about 45 °C | 8.4 A |
| about 45 to 60 °C | 4.2 A |
Before you charge
- 4.2 A is the data sheet’s standard charge current, with no condition printed [2]; the 2018 specification’s rated charge is the same 4.2 A, “Limiting 4.2A and constant 4.2V charge for 1.5h or 50mA at 23 oC.” [1] §4 item 1. The data sheet’s standard charge time is 1.5 h [2].
- The data sheet prints no maximum charge current. The 2018 specification’s “Maximum charging current” is 8.4 A, “See Section 4.14”: only from about 15 to 45 °C cell surface temperature, and 4.2 A outside it, from −20 to about 15 °C and from about 45 to 60 °C [1] §4 item 10, §4.14 (fig 5.5). The data sheet’s 8.4 A charge is a test at 23 °C, not a rating [2].
- Use a charger or BMS (battery management system) that ends charge at 4.2 V and stops charging outside 0 to 45 °C [2]. Set it to 4.2 A or less: the data sheet prints no maximum charge current [2], and the 2018 specification’s 8.4 A holds only while the cell surface is between about 15 and 45 °C [1] §4.14, which a charger without a sensor on the cell can’t check.
- Charge only between 0 and 45 °C [2]. The 2018 specification prints “-20~60 oC” and, in a caution, “0 oC to 60 oC” [1]; this page follows the newer data sheet’s narrower range. Put cells in the right way round: “The cell must be prevented from reverse-polarity charging.” [1] §7.2.2
06CYCLE LIFE AND STORAGE
Capacity over 500 cycles, and in storage.
The data sheet’s cycle chart: 4.2 A charge, then 10 or 20 A discharge, to 500 cycles at 23 °C [2]. The 2018 specification’s cycle-life minimums use 4.2 and 10 A discharge and 500 cycles [1] §5.3; its 10 A clause uses the same procedure as the chart’s 10 A test, but the chart prints no 100 % basis. Then how much charge a stored cell keeps [1] §5.4.
DIGITIZED FROM [2]FIG 6.1
Capacity over 500 cycles
10 A discharge20 A discharge
%
808590951000100200300400500
Cycle
Data: digitized from [2] “Cycle Characteristics”, markers only, one per cycle, as printed · “Charge: Constant Current-Constant Voltage, 4.2A, 4.2V, 50mA” · “Discharge: Constant Current, 10A, 20A, Cut off at 2.5V,” · “Rest 10min after 10A, Rest 30min after 20A” · “Temperature: 23oC” · [2] doesn’t print what 100 % is · the cycle-1 10 A marker lies exactly under the 20 A marker and is left out · [2] draws a one-cycle rise in the 10 A series after every 50th cycle, short blips near 10 A cycles 221–223 and 20 A cycles 260–262, and the 20 A series above the 10 A series at every cycle from 2 to 500, with no cause given · axis starts at 80 %
DATA TABLE · FIG 6.1
| TEST | 100 | 200 | 300 | 400 | 500 CYCLES |
|---|---|---|---|---|---|
| 10 A discharge | 91.93 % | 89.76 % | 88.08 % | 86.75 % | 85.61 % |
| 20 A discharge | 93.64 % | 91.62 % | 89.99 % | 88.57 % | 87.20 % |
DIGITIZED [2] · PRINTED [1]FIG 6.2
Capacity left: chart readings and printed minimums
Chart reading at cycle 500 [2]Minimum at cycle 500 [1] §5.3
CHART [2] · CYCLE 500 · 100 % NOT PRINTED
2018 SPECIFICATION [1] §5.3 · CYCLE 500 · % OF 3.90 Ah
Capacity at cycle 500, read from [2] (marker readings good to about ±0.1 point), beside the cycle-life minimums in [1] §5.3 at 4.2 and 10 A, each to 500 cycles with a printed 100 %: “The % = (Ah / 3.90) x 100%”. [2]’s 10 A test follows the same procedure as [1]’s 10 A clause (4.2 A charge to 4.2 V and 50 mA, 10 A to 2.5 V, 10 minutes’ rest, 23 °C; §5.1.5), but [2] prints no 100 % basis, so read each group on its own: the bars are not comparable across groups. mAh: percent × 3.90 Ah, calculated. A chart reading and a specification minimum, not a warranty.
PRINTED IN [1] + CALCULATEDFIG 6.3
Charge kept in storage
Capacity still in the cell after storage at 23 °C from 25 % state of charge, as printed in [1] §5.4: the first discharge after storage, “The % = (Ah / 4.0) x 100%”; mAh calculated as percent × 4.0 Ah, rounded half up. A cell stored at 25 % starts at about 25 %, so these show how much charge it keeps, not lasting loss. Orange: the longest storage period printed, 6 months. [1] §7.2.4 asks for long-term storage below 23 °C and a charge to 30 % at least once a year.
07TRANSPORT TESTS
What the UN38.3 report records.
AnTek Certification’s UN38.3 report [4], issued 2019-07-12 after test dates of 2019-06-24 to 2019-07-11, records “Passed” for T1–T5, T6 impact and T8 on the INR-21700-P42A; T6 crush and T7 (overcharge) are printed “N/A”. AnTek is a test lab, a separate company from Molicel; the report prints no accreditation mark. It is the only UN38.3 report on file for this cell. Its tables print what each cell did: a lab sample, not our lot.
PRINTED IN [4]FIG 7.1
Highest temperature, by abuse test
T5 external short 10 cells, fully charged · 85.4–101.3 °C
T6 impact 10 cells, “50% of the design rated capacity” · 27.51–28.10 °C
Pass limit, T5 and T6 external temperature “does not exceed 170 °C” [4]
Highest external temperature each cell reached, in °C, as printed in [4]: one tick per cell, the bar spans the lowest to the highest; cell counts are our tally of the printed rows. T5: case heated to 57 ± 4 °C, then shorted through 78.66–80.92 mΩ. The T5 peaks, 85.4–101.3 °C, are above the 85 °C cell-surface limit in [1] §7.2.3 2): a short circuit is an abuse test, not use. T6: a 9.1 kg mass dropped from 61 ± 2.5 cm onto a 15.8 mm bar across the cell. T8 forced discharge ran 20 cells at 45 A for 0.093 h, “at an initial current equal to the maximum discharge current specified by the manufacturer”; [4] prints no temperatures for it. Each test shown here is “Passed” in [4] (T6 crush and T7 are printed “N/A”): a lab sample, not our lot.
DATA TABLE · FIG 7.1
| TEST | CELLS | MAX °C, EACH CELL | RANGE |
|---|---|---|---|
| T5 external short | 10 | 90.9, 95.2, 99.4, 97.2, 89.0, 90.0, 92.0, 101.3, 85.4, 90.6 | 85.4–101.3 |
| T6 impact | 10 | 28.03, 27.51, 27.99, 27.88, 28.10, 27.68, 28.07, 27.92, 27.81, 27.65 | 27.51–28.10 |
PRINTED IN [4]FIG 7.2
Voltage kept through T1–T4
Pass criterion “not less than 90%” [4]
T1 altitude 99.95–100.00 % [4]
T2 thermal 96.87–97.28 % [4]
T3 vibration 99.95–100.00 % [4]
T4 shock 99.95–100.00 % [4]
Open-circuit voltage after each test, as a percent of the voltage just before it, printed for each of the 10 cells in [4]: one tick per cell. The cells started at 4.234–4.249 V, fully charged; five at first cycle and five after 25 cycles. The scale is in % and starts at 85 %.
PRINTED IN [4]FIG 7.3
Mass of the cells in the report
g
6566676869701234567891070 g maximum [2]
Cell
The lab weighed 10 samples before testing, as printed in [4]: 65.753–66.110 g before T1 (mean 65.94 g, our arithmetic), against the 70 g maximum, “70 g (Max)” [2] and “70.0 (Max)” [1]. Mass loss after each of T1–T4: 0.00–0.03 % [4]. The axis starts at 65 g.
DATA TABLE · FIG 7.3
| CELL | STATE | BEFORE T1 g |
|---|---|---|
| 01 | first cycle | 65.753 |
| 02 | first cycle | 66.018 |
| 03 | first cycle | 65.862 |
| 04 | first cycle | 66.075 |
| 05 | first cycle | 66.027 |
| 06 | after 25 cycles | 66.034 |
| 07 | after 25 cycles | 65.764 |
| 08 | after 25 cycles | 65.805 |
| 09 | after 25 cycles | 66.110 |
| 10 | after 25 cycles | 65.932 |
Safety tests in [1] §5.5 and §5.6
| TEST | CONDITIONS, AS PRINTED IN [1] | CRITERIA, AS PRINTED | SECTION |
|---|---|---|---|
| Temperature Shock | “Storage: -45 oC for 1h and 85 oC for 1h, transfer time within 10 seconds. Repeat cycle 10 times.” | “No fire or explosion” | [1] §5.5.1 |
| Heating | “At 100% SOC heat cell up in gravity convection and/or circulating air oven. Oven temperature is to be raised at a rate of 5ºC (± 2ºC) per minute to a temperature of 130ºC (± 2ºC). Hold oven at 130°C for 10 minutes.” | “No fire or explosion” | [1] §5.5.1 |
| Thermal test | “6 Hours @ 75 ± 2°C followed by 6 Hours @ - 40 ± 2°C x 10 Cycles (interval time of no more than 30 minutes between temperatures). Measurements taken after 10 cycles and 24 hours storage at 20± 5°C. (UN method)” | “Mass loss <0.1%, No leakage, venting, explosion, fire, disassembly, or rupture.” | [1] §5.5.1 |
| Short Circuit | “While in preheated oven and cell temperature reaches 55 ± 2°C, short circuit cell using a total external resistance < 0.1 ohm until cell temperature has returned to 55 ± 2°C. (UN method)” | “No disassembly, rupture or fire within 6 hours of test. Max temp: < 150°C.” | [1] §5.5.2 |
| Overcharge | “Charging at a current of 12.6A to 15V from the fully discharged state for 2.5hrs.” | “No fire or explosion” | [1] §5.5.2 |
| Forced Discharge | “Connect cell in series with a 12V DC power supply at a current equal to maximum discharge specified. (UN method)” | “No disassembly and no fire within 7 days of test” | [1] §5.5.2 |
| Crush | “Crush between two flat plates. Applied force is about 13KN.” | “No fire or explosion” | [1] §5.5.3 |
| Impact | “Impact by 15.8mmϕ bar with 9.1kg weight dropped from 61cm height on the flat surface.” | “No fire or explosion” | [1] §5.5.3 |
| Shock | “Subject to 6 shocks/axis, 18 total, of peak acceleration of150g and pulse duration of 6 ms. (UN method)” | “No leakage, mass loss, no venting, disassembly, no rupture and no fire. 90% voltage recovery” | [1] §5.6 |
| High Temp. Storage | “0.56A discharge capacity test after leaving at 85°C for 10h.” | “No leakage, no vent, no fire or explosion” | [1] §5.6 |
| Drop | “Drop from a height of 3ft onto a concrete floor 3 times each for bottom, side and header orientations (total=9 drops).” | “No visible electrolyte leakage, no temperature rising.” | [1] §5.6 |
| Vibration | “Subject to 7↔200Hz / 15 min vibration, 12x15 min /3 axes at amplitude of 0.8mm (1.6 mm total excursion). (UN method)” | “No leakage, mass loss, no venting, disassembly, no rupture and no fire. 90% voltage recovery” | [1] §5.6 |
| High Altitude Exposure | “Stored at a pressure of 11.6 kPa for 6 hrs at 20°C. (UN method)” | “No leakage, weight loss, no vent, fire or explosion, 90% voltage recovery” | [1] §5.6 |
The maker’s test method and pass criterion, copied as printed from the 2018 specification [1] §5.5 and §5.6. [1] lists these as tests the cell is specified to meet and prints no results. The 12.6 A overcharge current and the forced-discharge current are abuse-test conditions, not charge or discharge ratings. The UN38.3 results above are a different set of tests, from [4], with their own conditions: [1]’s short circuit starts at 55 ± 2 °C, [4]’s T5 at 57 ± 4 °C.
08DOCUMENTS
Where the documents differ.
The data sheet [2], “Version: 1.7”, prints no date; its PDF file was created 2023-06-14. The specification [1] is dated 2018-08-17. They print the same minimum capacity, voltages, discharge current, discharge temperature range and weight, but not the same labels or limits: [2] files the 45 A under “Continuous”, [1] calls it the “Maximum discharging current”; [2] prints a 0 to 45 °C charge range, [1] −20 to 60 °C (and 0 to 60 °C in a caution); only [1] prints a maximum charge current, 8.4 A inside a cell-surface window; [2] prints typical impedances, [1] an upper limit. Every rating on this page follows [2], the newer document; [1]’s figures appear where [2] prints none.
| ITEM | DATA SHEET [2], VERSION 1.7, NO DATE PRINTED | SPECIFICATION [1], 2018-08-17 |
|---|---|---|
| Capacity | “4200 mAh” typical, “4000 mAh” minimum; no condition printed | “4.0Ah (Minimum)”, “Rated discharge capacity after rated charge.”; no typical printed; §1 calls the cell “4.2 Ah” |
| Energy | 15.5 Wh typical, 14.7 Wh minimum; no basis printed | not printed |
| Discharge current | “Discharge Current” “Continuous” “45 A”; no condition printed | “Maximum discharging current” “45A”; remark “Cycle life is reduced at high rates.” |
| Standard and rated charge | “Charge Current” “Standard” “4.2 A”; “Charge Time” “Standard” “1.5 hr” | “Limiting 4.2A and constant 4.2V charge for 1.5h or 50mA at 23 oC.”; “90 min” |
| Maximum charge current | not printed; its charge chart plots an “8.4A charge” test | “Maximum charging current” “8.4A”, “See Section 4.14”: 8.4 A only from about 15 to 45 °C cell surface temperature (fig 5.5) |
| Charge temperature | “Temperature” “Charge” “0°C to 45°C”; no basis printed | “-20~60 oC” (§4 item 11) and “-20 oC ~ 60 oC” (§7.2.1 3)); “0 oC to 60 oC” in a caution (§7.3.2 3)); §4.14 chart −20 to 60 °C cell surface |
| Discharge temperature | “-40°C to 60°C”; no basis printed | “-40~60 oC”; no basis printed; “At a temperature of –40oC or less, the cell will show a significant decrease in discharge capacity.” (§7.2.3 2)) |
| Impedance | “Typical Impedance”: 10 mΩ “AC (1 KHz)”, 16 mΩ “DC (10A/1s)” | “Internal resistance” “≤ 15mΩ”, “Fresh cell measured by AC impedance at 1kHz” |
| Voltages | 3.6 V nominal, 4.2 V charge, 2.5 V discharge | “3.6V” nominal, “4.20 ± 0.05V” end of charge, “2.5V” end of discharge |
| Energy density | 615 Wh/l, 230 Wh/kg | not printed |
| Dimensions | “21.55 mm (Max)”, “70.15 mm (Max)” | “21.40 ± 0.15 mm”, “70.00 ± 0.15 mm”: upper limits 21.55 and 70.15 mm (our arithmetic) |
| Weight | “70 g (Max)” | “70.0 (Max)” |
| Can | “Steel” | not printed |
| Shipping and storage | not printed | “≥ 3.45V” shipping voltage; “< 35 oC” for shipping cells; “1 year” shelf life; at most 100 cells per inner box, 200 per master box (§11) |
| Vaping | “NOT FOR E-CIG OR VAPE” on the cell drawing, and a written prohibition (section 12 below) | not printed |
| Model code | “INR-21700-P42A” | “INR-21700-P42A”; §2.2 prints “INR-21700A-P42A” |
| Charts | charge (4.2 and 8.4 A); discharge rate at 23 °C; discharge temperature; cycle | §4.14 charge current against cell surface temperature only |
| Date | none printed; “Version: 1.7”; the PDF file was created 2023-06-14 | cover date 2018-08-17 (printed “8/17/2018”); “Rev.: 0.2” |
Text in quotation marks is copied as printed in [1] and [2]; other cells condense the printed rows, keeping their numbers and symbols; “not printed” is our note.
The SDS row for this cell, by revision
| TABLE 6, INR21700-P42A | [6] FSSF00058AP “Issue Date: 01-April-2019” |
[5] FSSF00058AR “Issue Date: 19-Dec-2019” |
[3] FSSF00058BJ “Issue Date: January 10, 2025” |
|---|---|---|---|
| Typical capacity | 4.20 Ah | 4.20 Ah | 4.20 Ah (4.00Ah Min) |
| Watt hour rating | 15.12 Wh | 15.12 Wh | 15.12 Wh (14.40 Wh Min) |
| Equivalent lithium content | 1.26 g | 1.26 g | 1.26 g |
| Weight | 67.0 g | 67.0 g | 70.0 g |
| Version field | “Version number: AB” | “Version number: AR” | “Version number: BI” |
Each SDS’s Table 6 row for INR21700-P42A, as printed; all three print 3.60 V. [3] adds the minimum capacity and minimum Wh, and prints 70.0 g where [5] and [6] print 67.0 g; [3]’s revision list doesn’t name the P42A, and the revisions between [5] and [3] are not on file. [5] and [6] are superseded and not posted; the ratings on this page don’t use them.
09COMPARE
Where the P42A sits.
Fifteen other 21700 cells, each from its own manufacturer document. A higher discharge rating usually costs capacity. The conditions behind each rating differ, so the table quotes each document’s wording.
DOCUMENTS · [1][2][7]FIG 9.1
Minimum capacity and discharge, side by side
- EVE 40PL INR21700/40PL4,000 mAh minimum · no typical printed70 A maximum, not continuous · with temperature cut-off, 75 °C recommended, 80 °C max.
- Tenpower 60XG INR21700-60XG5,900 mAh minimum · 6,000 nominal60 A continuous · 75 °C temp. cut-off; 40 A without; draft
- Molicel P50B INR-21700-P50B4,850 mAh minimum · 5,000 typical60 A continuous · 80 °C cut-off
- Samsung 45T CC4503F1014,400 mAh minimum · 4,500 typical50 A continuous · 80 °C temp. cut; 35 A without
- Samsung 50S INR21700-50S4,800 mAh rated minimum at 10 A · 5,000 typical45 A continuous · 80 °C temp. cut; 25 A without
- Molicel P45B INR-21700-P45B4,350 mAh minimum · 4,500 typical45 A max. continuous · no condition printed
- Samsung 40T INR21700-40T4,000 mAh minimum · no typical printed45 A continuous · 80 °C temp. cut; 35 A without
- Molicel P42A INR-21700-P42A4,000 mAh minimum · 4,200 typical45 A continuous · no condition printed
- Sony/Murata VTC6A US21700VTC6A4,000 mAh minimum · 4,160 nominal40 A continuous max. · 80 °C temp. cut
- Molicel M65A 21700-M65A6,400 mAh minimum · 6,500 ± 70 mAh at 0.2C, no typical or nominal label printed25.6 A rating type not printed · 90 °C cut-off; preliminary
- EVE 50E INR21700/50E4,900 mAh minimum · 5,000 nominal15 A max. continuous · no condition printed
- Molicel M50A INR-21700-M50A4,800 mAh minimum · 5,000 typical15 A continuous · no condition printed
- Samsung 50G INR21700-50G (Ver. B)4,900 mAh minimum · no typical printed14.7 A for continuous discharge · −20 to 30 °C; 9.8 A at 31 to 60 °C
- LG M50LT INR21700M50LTMinimum not stated by manufacturer · no mAh capacity printed; 1C = 4,800 mA14.4 A max. · 10 to 25 °C; 7.2 A at 25 to 55 °C, 2.4 A at −20 to 10 °C
- Samsung 58E CC5493F101 (Ver. A)5,330 mAh minimum · no typical printed10.66 A 2C for continuous discharge · 10.66 A = 2 × 5,330 mA, our arithmetic
- Samsung 50E INR21700-50E4,900 mAh minimum · no typical printed9.8 A for continuous discharge · no condition printed
Bars show each printed figure, not like-for-like ratings: the conditions differ, so read the condition beside each bar. Orange: the P42A, from its data sheet [2]: 45 A printed as a continuous discharge current with no condition (the 2018 specification [1] calls the same 45 A a maximum). The others are copied from their own documents [7]. Where a sheet prints two continuous figures, the bar shows the higher and the condition names the other; the EVE 40PL’s 70 A is printed as a “Maximum Discharge” with a temperature cut-off, not as continuous; the Samsung 58E’s 10.66 A is our arithmetic from 2C; the Samsung 50S’s 4,800 mAh is its rated minimum at 10 A, not a 0.2C minimum; the Molicel M65A sheet is preliminary R&D data. Bars start at zero: minimum capacity on a 0–7,000 mAh scale, discharge on 0–70 A. Pulse figures, and non-continuous figures where a sheet also prints a continuous one, are left out.
| CELL | TYPICAL OR NOMINAL mAh | MINIMUM mAh | DISCHARGE AS PRINTED | CHARGE AS PRINTED | MASS g |
|---|---|---|---|---|---|
|
EVE 40PL INR21700/40PL |
not printed | 4,000 | “Maximum Discharge: 70A(17.5C), 2.50V / With Temperature Cut-off / TRecommended: 75℃ / TMax: 80℃” (printed as a maximum; the word continuous is not printed) | “Maximum Charge: 8.0A(2.0C), 4.20±0.05V, CCCV 0.1A cut-off” | 67 max |
|
Tenpower 60XG INR21700-60XG |
6,000 nominal | 5,900 | “Max. continuous discharge current: 40A (without temperature cut off) / 60A(with 75℃ temperature cut-off)” (draft) | “Max. charging current: 16A” (no condition printed) | 76 max |
|
Molicel P50B INR-21700-P50B |
5,000 typical | 4,850 | “Discharge Current, Continuous: 60 A (80°C cut-off)” | “Charge Current, Maximum: 25 A (70°C cut-off)” | 71 max |
|
Samsung 45T CC4503F101 |
4,500 typical | 4,400 | “Max. continuous discharge (Surface temperature): 35A(Without temperature cut) / 50A(With 80℃ temperature cut)” | “Max. charge current: 9A (for step charge) / 6A (continuous charge)” | 72 max |
|
Samsung 50S INR21700-50S |
5,000 typical | 4,800 rated minimum at 10 A | “Max. continuous discharge (Surface temperature): 25A(Without temperature cut) / 45A(With 80℃ temperature cut)” | “Max. charge current: 6A (continuous charge)” | 72 max |
|
Molicel P45B INR-21700-P45B |
4,500 typical | 4,350 | “Maximum continuous discharging current: 45A” (no condition printed; remark: “Cycle life is reduced at high rates.”) | “Maximum continuous charging current: 9A” (remark: “High rate charge cycle will decay fast.”) | 70 max |
|
Samsung 40T INR21700-40T |
not printed | 4,000 | “Max. continuous discharge (Surface temperature): 35A(Without temperature cut) / 45A(With 80℃ temperature cut)” | “Rated charge: CCCV, 6A, 4.20 V, 100mA cut-off” (this spec prints no separate max. charge current item) | 70 max |
| Molicel P42A INR-21700-P42A |
4,200 typical | 4,000 | “Discharge Current” “Continuous” “45 A”, no condition printed [2]; the 2018 specification: “Maximum discharging current” “45A”, remark “Cycle life is reduced at high rates.” [1] | “Charge Current” “Standard” “4.2 A” [2], which prints no maximum; the 2018 specification: “Maximum charging current” “8.4A”, “See Section 4.14”: 8.4 A only from about 15 to 45 °C cell surface (fig 5.5) [1] | 70 max |
| Sony/Murata VTC6A US21700VTC6A |
4,160 nominal | 4,000 | “Continuous Maximum Discharging Current: 40A (With 80deg.C temperature cut)” | “Maximum Charging Current: 6A (Continuous)” | not printed placeholder “xx ±1.5g” |
| Molicel M65A 21700-M65A |
6,500 ± 70 at 0.2C; no typical or nominal label printed | 6,400 | “Discharge current: 25.6A (90℃cut-off)” (the word continuous is not printed; preliminary R&D data) | “Charge current: 6.5A (Standard) / 6.5A (Max)” | 72.5 ± 1.5, as printed |
|
EVE 50E INR21700/50E |
5,000 nominal | 4,900 | “Max Continuous Discharge current”: 15,000 mA (no condition printed) | “Max. Continuous Charge current” 2,500 mA (§5.9); “≤5000mA” in its charging-temperature row, 15 to 50 °C (§5.12); “Charge rates greater than 5000mA are not recommended.” (§12.2.1 b) | 69.0 ± 2.0, as printed; no maximum printed |
| Molicel M50A INR-21700-M50A |
5,000 typical | 4,800 | “Discharge Current, Continuous: 15 A” (no condition printed) | not printed on the V3 sheet (“Charge Current, Standard: 2.5 A”); Doc # INR21700M50A-01 Rev. 0.1: “Maximum charging current: 5.0A” (remark: “Recommended charge current 2.5A. High rate charge will cycle decay fast. See Section 4.14”) | 70 max |
| Samsung 50G INR21700-50G (Ver. B) |
not printed | 4,900 | “Max. Discharge Current (*²): 3C (14,700mA, for continuous discharge @ -20℃~30℃) / 2C (9,800mA, for continuous discharge @ 31℃~60℃)” | “Max. Charge Current: 4,900mA (not for cycle life)” | 71 max |
| LG M50LT INR21700M50LT |
not printed 1C = 4,800 mA | Not stated by manufacturer | “Max. Discharge Current (complete full charge)²⁾: -20 ~ 10℃ 0.5C (2,400mA) / 10 ~ 25℃ 3.0C(14,400mA) / 25 ~ 55℃ 1.5C(7,200mA)” (the sheet’s note 2 calls these the maximum continuous currents) | “Max. Charge Current (complete full charge)²⁾: 0 ~ 25℃ 0.3C (1,440mA) / 25 ~ 45℃ 0.7C (3,360mA)” | 68.2 ± 1.0, with tube and washer |
|
Samsung 58E CC5493F101 (Ver. A) |
not printed | 5,330 | “Max. Discharge Current (*²): 2C (for continuous discharge)” (the sheet prints 1C = 5,330 mA, so 10.66 A is our arithmetic; non-continuous figure not shown) | “Max. Charge Current: 1C (not for cycle life)” (1C = 5,330 mA as printed) | 74 max |
|
Samsung 50E INR21700-50E |
not printed | 4,900 | “Max. Discharge Current: 9,800mA (for continuous discharge)” (non-continuous figure not shown) | “Max. Charge Current: 4,900mA (not for cycle life)” | 69.5 max |
Text in quotation marks is copied from each manufacturer document: the data sheet [2] and the 2018 specification [1] for the P42A, and the documents in [7] for the others, as recorded in our comparison set, newest version on file, checked by a second reading; where a document prints a label and its value in separate table cells, the set joins them with a comma or a colon. Notes in parentheses are ours. The P42A’s charge column leads with the data sheet’s standard current, since [2] prints no maximum. Links go to the bare-cell listing in our store.
10PACK MATH
From one cell to a pack.
How the single-cell ratings scale in series (S) and parallel (P). Illustrative arithmetic, not a pack rating.
V MAX4.2 × S
“4.2 x N” V for N cells in series [1] §7.2.1
V NOMINAL3.6 × S
nominal voltage, 3.6 V [2]; “3.6V” [1]
CAPACITY4.0 × P
Ah minimum; 4.2 × P typical [2]
CONTINUOUS45 × P
A: the 45 A single-cell continuous rating, no condition printed [2], times P*
| CONFIG | CELLS | V MAX | V NOMINAL | Ah MINIMUM | Wh MINIMUM, 14.7 × S × P | CONTINUOUS A, 45 × P* | CELL MASS g, MAX |
|---|---|---|---|---|---|---|---|
| 1S1P | 1 | 4.2 | 3.6 | 4.0 | 14.7 | 45 | 70 |
| 2S1P | 2 | 8.4 | 7.2 | 4.0 | 29.4 | 45 | 140 |
| 3S1P | 3 | 12.6 | 10.8 | 4.0 | 44.1 | 45 | 210 |
| 4S1P | 4 | 16.8 | 14.4 | 4.0 | 58.8 | 45 | 280 |
| 2S2P | 4 | 8.4 | 7.2 | 8.0 | 58.8 | 90 | 280 |
| 3S2P | 6 | 12.6 | 10.8 | 8.0 | 88.2 | 90 | 420 |
| 4S2P | 8 | 16.8 | 14.4 | 8.0 | 117.6 | 90 | 560 |
| 7S3P | 21 | 29.4 | 25.2 | 12.0 | 308.7 | 135 | 1,470 |
| 10S3P | 30 | 42.0 | 36.0 | 12.0 | 441.0 | 135 | 2,100 |
| 10S4P | 40 | 42.0 | 36.0 | 16.0 | 588.0 | 180 | 2,800 |
| 13S4P | 52 | 54.6 | 46.8 | 16.0 | 764.4 | 180 | 3,640 |
| 14S5P | 70 | 58.8 | 50.4 | 20.0 | 1,029.0 | 225 | 4,900 |
CALCULATED FROM [2]FIG 10.1
Continuous current ceiling, by parallel count
45 A × P: the single-cell continuous rating, no condition printed [2], times the parallel count. [1] calls the same 45 A the “Maximum discharging current”, adds “Cycle life is reduced at high rates.” and limits the cell surface to 85 °C. A ceiling before derating, not a pack rating.
* 45 A × P multiplies the single-cell figure, “Discharge Current” “Continuous” “45 A” with no condition printed [2], by the number of cells in parallel. Wh = 14.7 Wh minimum [2] × S × P; [3] prints 14.40 Wh minimum (3.6 V × 4.0 Ah), about 2 % less. [2] draws no 45 A curve; at 30 A, the highest current it charts, the cell delivers about 4,098 mAh to the curve’s drawn end (fig 3.2). “E-One Moli Energy recommends that cells be assembled in a pack with protection circuit.” [1] §8: overcharge protection “under 4.3V/cell”, over-discharge protection at “2.5V/cell”, and an over-temperature warning that stops charge and discharge. The cell surface must not exceed 85 °C, with a 75 °C thermal cut-off recommended at high rates [1] §7.2.3 2). Derate, size the BMS, fusing and interconnects for the derated current, and use matched cells of one model and lot. Mass counts cells only. The UN38.3 report [4] covers the bare cell; a pack you build needs its own UN38.3 testing before it ships as UN3480.
11SIZE AND FIT
Ø21.55 × 70.15 mm, flat positive end.
Drawn at the data sheet’s maximum beside nominal outlines of two common formats. The 2018 specification prints 21.40 ± 0.15 by 70.00 ± 0.15 mm; its upper limits match the data sheet’s maximums. Both documents draw a flat positive end and name no top style [2], [1] §2.4.3.
PRINTED IN [1][2]FIG 11.1
Drawn to scale
All outlines drawn to the same scale. The P42A at its maximum dimensions [2]; the other outlines are nominal format sizes, for scale only.
| DIMENSION | VALUE | CONDITION |
|---|---|---|
| Diameter | 21.55 mm | maximum [2]; 21.40 ± 0.15 mm [1] |
| Height | 70.15 mm | maximum [2]; 70.00 ± 0.15 mm [1] |
| Mass | 70 g | maximum [2]; “70.0 (Max)” [1] |
| Positive end | Flat | as drawn in [2] and [1] §2.4.3; no top style named |
| Can | Steel | [2] |
| Volume | 25.6 cm³ | π × (21.55 mm ÷ 2)² × 70.15 mm = 25,587 mm³, the maximum envelope |
Check that your holder or device takes a flat-top cell 70.15 mm long (maximum) [2]. Spot-weld nickel strip for packs; don’t solder to the cell.
12USE IT RIGHT
Keep it inside its ratings.
What this cell is, and how to use it within its ratings.
- This is a bare cell: a component for protected packs and devices built for it. It is not a standalone consumer battery and not for vaping.
- Molicel’s data sheet prints: “This product is prohibited for use in and shall not be sold for use in e-cigarettes, vaporizers (e-cig, vape, mod) or any applications not permitted in Molicel product specifications and Molicel terms and conditions [...]” [2]; its cell drawing reads “NOT FOR E-CIG OR VAPE”.
- The 2018 specification lists its intended use as “Cordless screw driver, Cordless drill/driver, Cordless impact driver, Cordless tubing cutter, Cordless angle grinder, Cordless polisher/waxer, Power tool, Electrical vehicle, PHEV.” [1] §7.1.
- Flat positive end, as drawn in [2]. Check that your device takes a flat-top cell 70.15 mm long (maximum) [2].
- Charge on a lithium-ion (Li-ion) charger that stops at 4.2 V, at the standard 4.2 A or less, between 0 and 45 °C [2]. Stop discharging no lower than 2.5 V [1][2].
- Stay inside the ratings: at most 45 A continuous discharge (no condition printed [2]; a maximum in [1], “Cycle life is reduced at high rates.”), and the cell surface must not exceed 85 °C, with a 75 °C thermal cut-off recommended at high rates [1] §7.2.3 2). Before discharging below −30 °C, Molicel asks you to consult it first [1] §7.3.3 2).
- Replace a torn wrap before use. Carry cells in a case, never loose.
- For packs: matched cells of one model and lot, a BMS with the overcharge, over-discharge and over-temperature protection [1] §8 recommends, fusing, and a way for heat to leave.
Questions? Call 1-800-547-3050 or text 1-833-419-2192 to ask a person.
Documents
Linked, as published by their authors: the data sheet [2], “Version: 1.7”, the source of the ratings, which calls its contents “for reference only”; the SDS [3], written for all Molicel cells (its Table 6 lists the P42A); and the UN38.3 report [4]. Quoted, not posted: the 2018 specification [1], which Molicel marks confidential. Versions are listed as printed. Where [1] and [2] differ (whether 45 A is called continuous or a maximum, the charge temperature range, and [1]’s 8.4 A maximum charge, allowed only from about 15 to 45 °C cell surface temperature), this page follows [2] (section 08 above).
Ships from Stockbridge, GA. Most in-stock orders ship within 1 business day.
13QUESTIONS
Questions, answered.
Short answers. Where an answer comes from a document, it carries its source; the rest is standard handling practice. Anything else: call 1-800-547-3050 or text 1-833-419-2192.
Does the P42A have a protection circuit?
We sell it as a bare cell: a component for protected packs and devices built for it. No P42A document calls the cell protected or unprotected. The 2018 specification’s handling warning, “Do not disassemble or modify the cell. The cell contains safety and protection devices, that if damaged, may cause the cell to generate heat, explode or ignite.” [1] §7.3.1 2), is about devices inside the cell, which it doesn’t name; for packs it still says “E-One Moli Energy recommends that cells be assembled in a pack with protection circuit.” [1] §8. Use it in a pack with a battery management system (BMS) or in a device built for bare cells.
Is 45 A a continuous rating?
The data sheet calls it one: it prints “Discharge Current” “Continuous” “45 A”, with no temperature cut-off, duration or other condition beside it [2]. The 2018 specification gives the same 45 A as the “Maximum discharging current”, remark “Cycle life is reduced at high rates.” [1] §4 item 10, and asks: “Discharge the cell at the specified discharge current listed in section 4.10 or less.” [1] §7.2.3 1) (its “section 4.10” is §4 item 10). Its precautions add: “The cell surface temperature must not exceed 85°C.” and “Recommended thermal cut-off of 75°C at high rates.” [1] §7.2.3 2). No document prints a pulse rating; [1] §7.2.3 1) warns that a peak current above the maximum “may reduce the cell capacity”, without a figure. Either way, 45 A is the most either document allows. The data sheet charts no 45 A curve (its highest is 30 A, fig 3.2) and no cell temperature, the specification’s cycle-life minimums stop at 10 A [1] §5.3, and at 45 A the 16 mΩ typical DC impedance [2] works out to about 32 W of heat in one cell (fig 3.8, our arithmetic). Near 45 A, use a BMS with a temperature sensor on the hottest cell.
The 2018 specification says 8.4 A maximum charge, from about 15 to 45 °C cell surface only. Which applies?
The data sheet’s: charge at its standard 4.2 A or less, from 0 to 45 °C [2]. Neither document explains the difference. The data sheet [2], the newer document, prints a “Standard” charge current of 4.2 A and no maximum, with a charge range of 0 to 45 °C. The 2018 specification prints “Maximum charging current” 8.4 A, “See Section 4.14”: its chart allows 8.4 A only from about 15 to 45 °C cell surface temperature, and 4.2 A from −20 to about 15 °C and from about 45 to 60 °C [1] (fig 5.5). The data sheet’s “8.4A charge” curves are a test at 23 °C, not a rating (figs 5.1–5.3). This page follows the data sheet, the newer document (section 08 above).
What charger should I use?
A lithium-ion charger with a CC-CV profile (constant current, then constant voltage) that stops at 4.2 V, set to 4.2 A or less, the data sheet’s standard charge current [2]. Charge only from 0 to 45 °C [2]. Not a NiMH, LiFePO4 or lead-acid charger. The data sheet’s standard charge time is 1.5 h [2]; its 4.2 A charge trace ends at about 81 min (fig 5.1).
How long will it run at my current?
Runtime ≈ capacity ÷ current. From the data-sheet curves, from full at 23 °C: about 5 h 03 min at 0.84 A, 60 min at 4.2 A, 25 min at 10 A, 12 min at 20 A and 8.2 min at 30 A (fig 3.7) [2]. For a draw between 4.2 and 10 A at 23 °C, divide 3,900 mAh, the specification’s minimum at both currents [1] §5.2, by your current in mA to get hours: at 5 A, 3,900 ÷ 5,000 = 0.78 h, about 47 min. [1] prints no minimum above 10 A, and [2] draws no curve above 30 A. In the cold, start from the lower figures in fig 4.4.
How much does cold reduce capacity?
In the data sheet’s temperature chart, each curve to its end at about 2.5 V: about 4,032 mAh at 0 °C, 3,851 mAh at −20 °C, 3,704 mAh at −30 °C and 3,620 mAh at −40 °C, against 4,177 mAh at 23 °C (fig 4.4) [2]. The chart discharges at 4.2 A after a charge at 23 °C and doesn’t say whether these are air or cell temperatures. The specification’s minimums at 4.2 A are 3,400 mAh at 0 °C and 3,300 mAh at −20 °C to 2.5 V, and 3,300 mAh at −30 °C to 2.0 V [1] §5.2. It adds: “At a temperature of –40oC or less, the cell will show a significant decrease in discharge capacity.” [1] §7.2.3 2). Voltage also drops in the cold (fig 4.5), so a device may cut off early. Don’t charge below 0 °C [2].
How many cycles will it last?
The 2018 specification sets at least 80 % after 500 cycles at 4.2 A or 10 A discharge, where 100 % is 3.90 Ah (at least 3,120 mAh, calculated), at 23 °C [1] §5.3. The data sheet’s chart reads about 85.6 % at cycle 500 with 10 A discharge and 87.2 % with 20 A, against a 100 % it doesn’t define (fig 6.1) [2]. Neither document gives an end-of-life cycle count. Heat, current, depth of discharge and storage all change the result.
Why do the energy figures differ?
The data sheet prints 15.5 Wh typical and 14.7 Wh minimum [2] and doesn’t say how it found them. The SDS prints “15.12 Wh (14.40 Wh Min)” under “Watt Hour Rating (Wh) (Volts x Ah)”: 3.6 V × 4.2 Ah and × 4.0 Ah [3]; the UN38.3 report prints 15.1 Wh [4]. Our integration of the data sheet’s 0.84 A curve gives about 15.58 Wh (fig 1.5).
What chemistry is it?
Lithium-ion. Molicel’s data sheet and 2018 specification for the P42A don’t name a cathode chemistry, and we don’t infer one from the model code. The SDS’s ingredient table, written for all the Molicel cells it covers, lists a cathode that “Includes one or more of the following:” Lithium Cobaltite, Manganese, Nickel, Aluminum, and notes “*Quantities may vary depending on cell or battery model.” [3] Table 3.
Can I use it in a vape or e-cigarette?
No. Molicel’s data sheet prints “This product is prohibited for use in and shall not be sold for use in e-cigarettes, vaporizers (e-cig, vape, mod) or any applications not permitted in Molicel product specifications and Molicel terms and conditions [...]” [2], and its cell drawing reads “NOT FOR E-CIG OR VAPE”. We sell bare cells as components for protected packs and devices built for them, not for vaping.
Can I solder to it?
Don’t solder directly to the cell: the heat can damage the seal and internal parts. Spot-weld nickel strip, or use a holder; [1] §7.4.1 asks you to “prevent sparking during welding”.
Can I mix P42A cells with other cells?
No, not in the same pack: “Do NOT mix different cell types or manufacturers within a battery pack.” [1] §7.4.2. Use cells of the same model and lot, at the same state of charge. In series, the weakest cell reaches the 2.5 V cut-off [2] first and limits the whole pack, and mismatched cells drift further apart with every cycle.
How should I store spare cells?
In a case, away from metal objects (“Do not carry or store the cells together with necklaces, hairpins or other metal objects.” [1] §7.3.1 1)(4)), somewhere dry. The 2018 specification asks: “In case of long-term storage, store the cell at <23 oC, low humidity, noncorrosive gas atmosphere.” and, for storage longer than a year, “charge it at least once 1 year. And in this case, the cell is recommended to be charged to 30% capacity.” [1] §7.2.4. It also says “Do not store cell in humid environment.” Shipped cells: below 35 °C [1] §4 item 12. Check the voltage every few months.
How does it ship?
As UN3480, lithium-ion batteries, Class 9, under the SDS [3] §14; UN3481 when packed with or contained in equipment. Molicel ships cells “at a state of charge not to exceed 30% of rated capacity” [1] §10. The UN38.3 report [4] covers the bare cell; a pack built from these cells needs its own UN38.3 testing.
14SOURCES
Sources and method.
Where every number on this page comes from.
- + Source: [1] E-One Moli Energy Corp., Approval Sheet, “Cell Specifications of INR-21700-P42A”, Doc # INR21700P42A-01, “Rev.: 0.2”, 8/17/2018 (as printed); on file; not posted: every page is marked “-- CONFIDENTIAL --” and “Proprietary of E-One Moli Energy Corp.”, so we quote it but don’t post it. Questions about its figures: call or text us
- + Source: [2] Molicel, Product Data Sheet, Model INR-21700-P42A, “Version: 1.7” (as printed; no date or document number printed); it carries no confidential marking and says “The information contained herein is for reference only and does not imply a performance guarantee or a product warranty.”; retrieved 2026-11-07 · Data sheet PDF
- + Source: [3] Molicel, Safety Data Sheet FSSF00058BJ, Molicel Rechargeable Lithium-ion cells and multi-cell battery packs; its version field prints BI; “Issue Date: January 10, 2025”; Table 6 lists INR21700-P42A; retrieved 2026-11-07 · SDS PDF
- + Source: [4] AnTek Certification Inc., Lithium Ion Battery Safety Testing Report TW1906114-001, INR-21700-P42A, to UN Manual of Tests and Criteria ST/SG/AC.10/11/Rev.6/Amend.1; test dates 2019-06-24 to 2019-07-11; issued 2019-07-12; retrieved 2026-11-07 · UN38.3 report PDF
- + Source: [5] Molicel SDS FSSF00058AR, “Issue Date: 19-Dec-2019”, and [6] Molicel SDS FSSF00058AP, “Issue Date: 01-April-2019” (its version field prints AB): superseded by [3]; on file for the document comparison only, not posted
- + Source: [7] Samsung INR21700-40T, Spec. No. INR21700-40T, Version No. 0.0, December, 2017 (headed “SAMSUNG SDI Confidential Proprietary”; every page watermarked “Tentative”; no version suffix) (as printed); on file
- + Source: [7] Samsung CC4503F101, Spec. No. CC4503F101, Version No. V0.1 (Draft), Date of Application 24/02/01 (as printed); on file
- + Source: [7] Samsung INR21700-50E, Spec. No. INR21700-50E, Version No. V1.0 (General Version), 2018/07/11 (as printed); on file
- + Source: [7] Samsung INR21700-50G (Ver. B), Spec. No. INR21700-50G, Version No. Draft V0.2, Date of Application 2023/05/10 (as printed); on file
- + Source: [7] Samsung INR21700-50S, Spec. No. INR21700-50S, Version No. V1.0, Date of Application 2021/04/19 (as printed); on file
- + Source: [7] Samsung CC5493F101 (Ver. A), Spec. No. CC5493F101, Version No. Draft V0.1, Date of Application 2023/12/04 (as printed); on file
- + Source: [7] Molicel INR-21700-P45B, Doc # INR21700P45B-01, Rev. 0.2, 2022/01/06 (Approval Sheet (tentative)) (as printed); on file
- + Source: [7] Molicel INR-21700-P50B, Product Data Sheet Version 1.1 (as printed); on file
- + Source: [7] Molicel INR-21700-M50A, Product Data Sheet, no version printed (file INR21700M50A-V3-80097, PDF dated 2020-04-01); max charge from Doc # INR21700M50A-01, Rev. 0.1, 6/4/2019 (as printed); on file
- + Source: [7] Molicel 21700-M65A, R&D Update, M65A performance (preliminary); no version printed (file dated 2025.04.29) (as printed); on file
- + Source: [7] LG INR21700M50LT, Doc No. 2021-LSD-MBD-b00002, Rev 2, 2021-07-06 (“For (Promotion) only”; marked “This document is NOT final version”) (as printed); on file
- + Source: [7] Sony/Murata US21700VTC6A, Tohoku Murata Spec. No. KU※※※※※, Ver. 0.1, 1st issue 2017.11.27 (Products Information, Tentative) (as printed); on file
- + Source: [7] EVE INR21700/40PL, Spec. No. PBRI-INR21700/40PL-D06-01, Version No. A, June, 2023 (as printed); on file
- + Source: [7] EVE INR21700/50E, Document No. RD-EVE INR21700/50E-S76-LF, Edition A (initial release), Effective Date 2022.5.23 (as printed); on file
- + Source: [7] Tenpower INR21700-60XG, Spec. No. INR21700-60XG, Version No. V0.1 draft, Effective Date 2025/12/09 (draft; every page marked TENPOWER confidential proprietary) (as printed); on file
- + Note on [7]: quoted, not linked: several of these documents are marked confidential, draft or tentative (see each line), and this page links only the P42A’s own documents. The data sheets the store posts are in our data-sheet library.
- + Method: curves read from the vector drawings in the data sheet [2] (axis mapping from the charts’ own grid lines and ticks, one stroke color and line style per series), each checked against the original by a second reading; within about ±0.5 % of each axis. Where a curve’s start lies under another curve in [2], the redraw starts at its first visible point; where a stretch is hidden (the 23 °C curve, about 3,660–4,010 mAh), the line is broken there, and our arithmetic uses the digitized path. The dotted 8.4 A charge traces are short dashes in [2], joined here with straight lines. Charge put in is current × time summed along the digitized current traces. Fig 5.5 is drawn from figures printed in [1], with its two step temperatures read from the chart. Calculated figures use the formula printed under each; C-rates use our basis, 1C = 4.2 A, since no P42A document prints one. Illustrative; check figures against the documents.
- + Not shown from [1]: its warranty clause (§9), which applies to Molicel’s direct customer.
- + Not shown from [3]: its hazard statements, and its storage advice written for all Molicel cells; the storage clauses on this page are [1]’s.
- + Not shown: our own lot data. We will add rows for our lot only once our incoming-inspection procedure is published, with sample size, instrument and date.
Customer Reviews
Overall rating: 4.9 / 5 from 1126 reviews.
I’ve used the Molicel P42A for some time now and think it’s the best option for my vaping setup. 18650BatteryStore is the only place I use for my batteries.
Love the molicel 21700 batts, they last a good days worth of use on a single charge.
I have now received my parcel.
Great prices and fast shipping
5 stars plus. Will buy from again thanks
Best price. Quick delivery. Very happy!
It is the best
Molicell doesn't disappoint when I'm rebuilding failed Samsung packed power tool batteriesm
😊
My order was complete. Shipping was fast. Happy with my order. I will definitely use this company again. Satisfied with my purchase
Batteries arrived on time, are exactly what I needed! Thanks.
Muy buenas la recomendó
Shipping was fast. I always buy/trust 18650BatteryStore.com. Thank you!!!
Each battery came at 3.6v, packed nicely and shipped on time.
Amazing servicr
Great prices on the Molicel 21700 p42a cells!! Fast delivery too!! Will definitely be shopping here again!
Excellent product, fast shipping, and a trustworthy website. There is a reason so many flashlight enthusiasts recommend this site for batteries. Amazon and other sites unfortunately sometimes unknowingly sell counterfeit rewrapped batteries so I'm grateful this place exists for peace of mind!
Great batteries. Hold up well, great for higher draw flaslights, etc.
Good
Perfecto
Wanted p50b but was out of stock. Really wish yall would get the Epoch 21700 back in stock. Don’t look like that’s ever gonna happen.
Fast shipping
Great internal resistance all of them are within .1 milliohm.
Quick shipping, smooth process. I would recommend buying from this company & will do so again.
Been using this lithium battery for over 8 yrs. I use 2 of these per day every day. They each get recharged every day 365 days a yr. They aren't 100% depleted but are about 60 to 70% depleted when it charge them. They last for years and years and have only worn out 3 or 4 over the last 8 yrs. I do keep spares on hand just in case. I use these in high end flash lights, my Vape device, rechargeable fan that runs almost 24/7. You can't go wrong with this battery I've proofed that.
First time using these cells, so I don't know about long term, but are working very well out of the gate. Mainly for short-term, high-energy demand, 20 Volt Max power tools.
A+
good battery good packaging good price. love it
10/10 supplier
Great customer experience!
Long battery life.
This, Molicel 21700 IS THE BEST!
I’ve been purchasing batteries from 18650 Batteries for years now, both the titular 18650’s and now 21700’s. I definitely do not use them for vaping, and definitely haven’t been using them for vaping for the better part of a decade now. They’re always solid, and the best source for not vaping batteries around.
Thank you for the batteries, I'm using these with my new SKYRC MC5000 charger, and they are charging great. Using these with my EMISAR flashlights. 21700 is the perfect battery size.
You guys are great as is your customer service. It is rare this day and age when you can talk to a knowledgeable person on the phone. Keep up the good work! On the other hand I had two batteries out of my order that would not fully charge. What can be done?
works perfectly
EXCELENTE!!!
To be honest, I thought that order was 18650's. Had to go look at the invoice, but there it was, 21700's. It all worked out because I just got some Makita battery kits that took 21700's. This company is so darn good they sent me what I needed, not what I wanted.
Great price and quality for battery pack building!