Illustrative render of the FST 20650-3350mAh cell✱ Render
Illustrative render generated from published specifications. Not a photograph of the actual cell.
20650NMC

FST 20650-3350mAh

FST
Capacity3350 mAh12.06 Wh
Rated continuous6.7 A6.7A
Resistance35DC internal resistance
Voltage window3.6 V2.8 – 4.2 V
Standard charge1675 mA~2 h to full

Full specifications

Electrical
ChemistryNMC
Nominal voltage3.6 V
Max charge voltage4.2 V
Discharge cutoff2.8 V
Max continuous discharge6.7A
Standard charge current1675 mA
Standard discharge current1675mA
Internal resistance35 mΩ
Physical
Form factor20650
Wrap colorBlue (Dark)
Insulator ringWhite
Performance
Capacity3350 mAh
Energy12.06 Wh

At the standard 1675 mA charge rate, a full charge takes about 2 hours. The last bit is a slow taper to top it off.

Voltage operating window

Cutoff
2.8V
Nominal
3.6V
Max charge
4.2V

Usable range: 1.4V

C-rate conversion: FST 20650-3350mAh (3350mAh)

C-RateCurrent (A)Theoretical runtime
0.2C0.67 A5h 00m
0.5C1.68 A2h 00m
1C3.35 A1h 00m
2C6.7 A30m

Highlighted row is closest to the rated 6.7A continuous discharge.

Charging

RateCurrentEstimated time
0.5C1,675 mA~2h 00m
1C3,350 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.

Pack scaling

Series voltage configurations

ConfigNominal VMax VMin VCommon use
1S3.6V4.2V2.8VFlashlights, single-cell devices
2S7.2V8.4V5.6VRC vehicles, 7.2V packs
3S10.8V12.6V8.4VPower tools (10.8V nominal)
4S14.4V16.8V11.2VEbike (small), some power tools
7S25.2V29.4V19.6VEbike (24V system)
10S36V42V28VEbike (36V system)
13S46.8V54.6V36.4VEbike (48V standard)
14S50.4V58.8V39.2VEbike (52V high-power)
16S57.6V67.2V44.8VDIY powerwall

Parallel capacity scaling

ConfigCapacityEnergyMax discharge
1P3,350 mAh12.1 Wh6.7 A
2P6,700 mAh24.1 Wh13.4 A
3P10,050 mAh36.2 Wh20.1 A
4P13,400 mAh48.2 Wh26.8 A
5P16,750 mAh60.3 Wh33.5 A
6P20,100 mAh72.4 Wh40.2 A

Example pack configurations

7S2P
24V ebike / small pack
14 cells25.2V nominal6,700mAh169Wh13A max
13S4P
48V ebike standard
52 cells46.8V nominal13,400mAh627Wh27A max
16S4P
DIY powerwall
64 cells57.6V nominal13,400mAh772Wh27A max
4S6P
Power tool replacement
24 cells14.4V nominal20,100mAh289Wh40A max

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 PacksMarginal. Check your motor's peak draw first. You might get voltage sag under load.
Car AudioNot enough discharge for car audio amplifiers. You need at least 15-20A continuous for most setups.
High-Drain VapingBelow the 25A Mooch CDR threshold that high-drain vaping needs. Use a higher-drain cell.
FlashlightsHigh capacity means long runtime. Great for everyday carry and extended use.
Power ToolsNot enough discharge or capacity for power tool use.

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 2.8V.
  • 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.