P42A (21700) is a high-current 4200 mAh Li-ion INR cell designed for high-power battery packs where high energy density and high discharge current are required. Ideal for e-bikes, e-scooters, e-motorcycles and other projects using 3.6 V nominal voltage with BMS.
Specifications
- Format: 21700 (unprotected cell)
- Capacity (typical): 4200 mAh
- Nominal (“standing”) voltage: 3.6 V
- Max. charging voltage: 4.20 V
- Min. discharge voltage (cut-off): 2.50 V
- Chemistry: Li-ion INR
- Discharge current: up to ~45 A transient / ~30-35 A steady*
* Actual limits depend on BMS, cooling and manufacturer’s guidelines.
Key benefits
- High capacity 4200 mAh with high current – ideal for power modifications.
- Stable INR chemistry – a good balance of energy density, safety and cyclability.
- 21700 format – higher energy density compared to 18650.
Notes for use
- BMS (over/under voltage, current, short circuit protection) required.
- Spot welding (nickel/copper strips) is recommended; avoid overheating when soldering.
- Do not use damaged cells; charge only with Li-ion chargers according to specification.
FAQ
Does this cell have built-in protection (PCB)?
No, this is an unprotected 21700 cell – use in packages with BMS.
Is it suitable for a single cell with modules?
It is possible if a suitable charging/management module with guards is used.
P42A, 21700 cell, 4200mAh Li-ion, high current battery, e-bike battery cell, Molicel P42A, 3.6V Li-ion, BMS
