Illustrative render of the Keeppower NCR20700B cell✱ Render
Illustrative render generated from published specifications. Not a photograph of the actual cell.
20.35 × 70.3 mm · 63 g
20700NCA Mooch-tested · 15 A

Keeppower NCR20700B

Keeppower
Capacity4250 mAh15.3 Wh · 242.86 Wh/kg
Mooch continuous15 ASize to this figure
Voltage window3.6 V2.5 – 4.2 V
Standard charge2000 mA~2.1 h to full

At 4250 mAh, this ranks #1 of 12 20700 cells in our database. Near the top for capacity among 20700 cells. More capacity than 100% of 20700 cells in our database, but lower discharge than average.

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Full specifications

Electrical
ChemistryNCA
Nominal voltage3.6 V
Max charge voltage4.2 V
Discharge cutoff2.5 V
Max continuous discharge15A (Mooch-tested)
Mooch CDR (trusted)15 A
Standard charge current2000 mA
Physical
Form factor20700
Dimensions20.35mm × 70.3mm
Weight63 g
Top typeFlat Top
ProtectedNo
Performance
Capacity4250 mAh
Energy15.3 Wh
Specific energy242.86 Wh/kg
Energy density669.14 Wh/L
Power density (gravimetric)857 W/kg
Power density (volumetric)2,362 W/L
Operating Limits
Charge temp10°C to 45°C
Discharge temp-20°C to 60°C

Independent test data: Mooch's test of the NCR20700B ↗

At the standard 2000 mA charge rate, a full charge takes about 2.1 hours. The last bit is a slow taper to top it off.

Voltage operating window

Cutoff
2.5V
Nominal
3.6V
Max charge
4.2V

Usable range: 1.7V

C-rate conversion: Keeppower NCR20700B (4250mAh)

C-RateCurrent (A)Theoretical runtime
0.2C0.85 A5h 00m
0.5C2.13 A2h 00m
1C4.25 A1h 00m
2C8.5 A30m
3C12.75 A20m

Highlighted row is closest to the rated 15A continuous discharge.

Charging

RateCurrentEstimated time
Standard2,000 mA~2h 08m
0.5C2,125 mA~2h 00m
1C4,250 mA~1h 00m

These are estimates for the constant-current phase. Real charge time is a bit longer because of the slow taper at the end.

Datasheet

Pack scaling

Series voltage configurations

ConfigNominal VMax VMin VCommon use
1S3.6V4.2V2.5VFlashlights, single-cell devices
2S7.2V8.4V5VRC vehicles, 7.2V packs
3S10.8V12.6V7.5VPower tools (10.8V nominal)
4S14.4V16.8V10VEbike (small), some power tools
7S25.2V29.4V17.5VEbike (24V system)
10S36V42V25VEbike (36V system)
13S46.8V54.6V32.5VEbike (48V standard)
14S50.4V58.8V35VEbike (52V high-power)
16S57.6V67.2V40VDIY powerwall

Parallel capacity scaling

ConfigCapacityEnergyMax discharge
1P4,250 mAh15.3 Wh15 A
2P8,500 mAh30.6 Wh30 A
3P12,750 mAh45.9 Wh45 A
4P17,000 mAh61.2 Wh60 A
5P21,250 mAh76.5 Wh75 A
6P25,500 mAh91.8 Wh90 A

Example pack configurations

7S2P
24V ebike / small pack
14 cells25.2V nominal8,500mAh214Wh30A maxCell weight: 0.88 kg (add ~15% for wiring and BMS)
13S4P
48V ebike standard
52 cells46.8V nominal17,000mAh796Wh60A maxCell weight: 3.28 kg (add ~15% for wiring and BMS)
16S4P
DIY powerwall
64 cells57.6V nominal17,000mAh979Wh60A maxCell weight: 4.03 kg (add ~15% for wiring and BMS)
4S6P
Power tool replacement
24 cells14.4V nominal25,500mAh367Wh90A maxCell weight: 1.51 kg (add ~15% for wiring and BMS)

Design a custom pack with this cell:

Application suitability

PowerwallsHigh capacity means more stored energy per cell. Fewer cells needed for a given kWh target.
Ebike PacksGood balance of capacity for range and discharge for hills. Works well in most ebike packs.
Car AudioMight work for smaller setups. Check your amp's peak current draw.
High-Drain VapingUsable in regulated mods at moderate wattage. Not recommended for mechanical mods.
FlashlightsHigh capacity means long runtime. Great for everyday carry and extended use.
Power ToolsSufficient discharge and capacity for most power tool packs.

Physical dimensions

Dimensions20.35mm × 70.3mm
TopFlat Top
Format20700

Similar cells

Same format and chemistry, within ±500mAh capacity:

CellmAhCDRWhWeightWh/kg
Keeppower NCR20700B (this cell)425015A15.363g242.86
Enercig 20700 4000mAh 15A400015A14.463g229

Frequently asked questions

Handling and safety

Lithium cells can be dangerous if mishandled. A few things to keep in mind:

  • Never charge above 4.2V or discharge below 2.5V.
  • Store cells at around 3.6-3.8V (roughly 40-60% charge) for long-term storage.
  • Don't mix cells with different capacities, chemistries, or states of charge in a pack.
  • Inspect wraps before use. A torn wrap can cause a short circuit.
  • Always use a BMS or balance charger appropriate for your pack configuration.
  • Keep cells away from metal objects, keys, and coins. A short across the terminals can cause fire.

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Specs come from manufacturer datasheets and independent testing; Mooch-tested discharge ratings are shown when available because they reflect real continuous performance better than headline datasheet numbers. Browse the full 18650 & 21700 cell database to compare every cell.

Disclaimer: We do our best to keep the information on this page accurate, but we cannot guarantee that all specifications are correct or up to date. Cell characteristics can vary between production batches and may change over time. Do not rely solely on this data for safety-critical applications. Always verify against the manufacturer's official datasheet before use.