Side-by-side comparison of Molicel INR18650-P28A (18650) and Molicel INR21700-P42A (21700)
| Molicel INR18650-P28A | Molicel INR21700-P42A | |
|---|---|---|
| Capacity | 2800 mAh | 4200 mAh |
| Nom. Voltage | 3.6 V | 3.6 V |
| Max Current | 35 A | 45 A |
| Weight | 46 g | 70 g |
| Energy | 10.1 Wh | 15.1 Wh |
| Energy Density | 219 Wh/kg | 216 Wh/kg |
| Form Factor | 18650 | 21700 |
| Typical R_int | 22.0 mOhm | 17.6 mOhm |
Showing 10A discharge rate for both cells
| Current | Molicel INR18650-P28A | Molicel INR21700-P42A |
|---|---|---|
| 0.56A | 22.0 | — |
| 0.84A | — | 17.6 |
| 2.8A | 20.0 | — |
| 4.2A | — | 15.2 |
| 10.0A | 19.0 | 15.2 |
| 20.0A | 18.4 | 14.7 |
| 30.0A | 18.0 | 14.4 |
Values in mΩ. Bold = lowest resistance at that current.
The Molicel P42A offers 50% more capacity (4200 vs 2800 mAh). The Molicel P42A supports higher continuous discharge (45A vs 35A), making it better for high-drain applications. The Molicel P28A is lighter at 46g. Note: these are different form factors (18650 vs 21700), so direct substitution is not possible without pack redesign.