FP 18650-1800mAh
At 1800 mAh, this ranks #243 of 279 18650 cells in our database. On the lower end for capacity among 18650 cells. A mid-range 18650 cell. Solid for builds that don't need extreme capacity or discharge.
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See the wrap, markings, and terminals up close.
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Full specifications
| Electrical | |
|---|---|
| Chemistry | Li-ion |
| Nominal voltage | 3.6 V |
| Max charge voltage | 4.2 V |
| Discharge cutoff | 2.5 V |
| Standard charge current | 900 mA |
| Standard discharge current | 900mA |
| Physical | |
| Form factor | 18650 |
| Dimensions | 18.3mm × 65mm |
| Weight | 46 g |
| Top type | Button Top |
| Protected | No |
| Wrap color | Green |
| Insulator ring | White |
| Performance | |
| Capacity | 1800 mAh |
| Energy | 6.48 Wh |
| Specific energy | 140.87 Wh/kg |
| Energy density | 379.03 Wh/L |
At the standard 900 mA charge rate, a full charge takes about 2 hours. The last bit is a slow taper to top it off.
Voltage operating window
2.5VNominal
3.6VMax charge
4.2V
Usable range: 1.7V
Charging
| Rate | Current | Estimated time |
|---|---|---|
| 0.5C | 900 mA | ~2h 00m |
| 1C | 1,800 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
| Config | Nominal V | Max V | Min V | Common use |
|---|---|---|---|---|
| 1S | 3.6V | 4.2V | 2.5V | Flashlights, single-cell devices |
| 2S | 7.2V | 8.4V | 5V | RC vehicles, 7.2V packs |
| 3S | 10.8V | 12.6V | 7.5V | Power tools (10.8V nominal) |
| 4S | 14.4V | 16.8V | 10V | Ebike (small), some power tools |
| 7S | 25.2V | 29.4V | 17.5V | Ebike (24V system) |
| 10S | 36V | 42V | 25V | Ebike (36V system) |
| 13S | 46.8V | 54.6V | 32.5V | Ebike (48V standard) |
| 14S | 50.4V | 58.8V | 35V | Ebike (52V high-power) |
| 16S | 57.6V | 67.2V | 40V | DIY powerwall |
Parallel capacity scaling
| Config | Capacity | Energy |
|---|---|---|
| 1P | 1,800 mAh | 6.5 Wh |
| 2P | 3,600 mAh | 13 Wh |
| 3P | 5,400 mAh | 19.4 Wh |
| 4P | 7,200 mAh | 25.9 Wh |
| 5P | 9,000 mAh | 32.4 Wh |
| 6P | 10,800 mAh | 38.9 Wh |
Example pack configurations
Design a custom pack with this cell:
Physical dimensions
Similar cells
Same format and chemistry, within ±500mAh capacity:
| Cell | mAh | CDR | Wh | Weight | Wh/kg |
|---|---|---|---|---|---|
| FP 18650-1800mAh (this cell) | 1800 | — | 6.48 | 46g | 140.87 |
| Nitecore NL1821 | 2100 | 38A | 7.6 | 45.3g | 167 |
Build with this cell
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.