BK51 | High-Performance 21700 Cell Comparison

MxF VTB BK51 vs. Molicel P45B vs. P50B

Consolidated view of key specifications and a 40 A discharge benchmark (temperature, energy and average voltage) for BK51 versus two typical market reference cells.

BK51 Key Specs

Cell ModelINR-21700-BK51
Nominal Voltage3.6 V
Typical Capacity5.1 Ah | 18.36 Wh
Energy Density278 Wh/kg | 728 Wh/L
Max Discharge41 A @ 45 s | 102 A @ 7 s
Max Charge Current26 A (0–80% SOC)
Cycle Life1000 cycles ≥ 70% (40 A discharge | 10 A charge)
DCIR / ACIR6.5 mΩ / 2.8 mΩ
Operating Range−40 ~ 80 °C
Power Output450 W (25 °C) / 100 W

Temperature Curve

(77 °C vs. 89 °C vs. 89 °C)
Discharge progress (normalized) Voltage (V) MxF BK51 Molicel P45B Molicel P50B
MxF BK51 Molicel P45B Molicel P50B

40 A Discharge Curve

Summary Table
Battery Capacity Energy Avg. V Temp (°C)
MxF BK51 5100 17.24 3.38 77
Molicel P50B 4791 15.76 3.29 89
Molicel P45B 3655 12.44 3.40 89
Higher Capacity · Lower Temperature · Stable Voltage · Superior Power Output