21700A (Ampace) 21700 Li-Ion 4000mAh
Ampace

21700A

21700 Li-Ion 4000mAh rated
from €3.25/cell
102%
of rated capacity
at 500mA
12
independent tests
€3.25
best price / cell
68.2g
avg weight
2 measurements
Single cell GTIN: 6097331840898
Nkon
Netherlands · nkon.nl
4 days ago
€3.25

This battery delivered 102% of its rated capacity (4079mAh tested vs 4000mAh rated) at 500mA. Higher current tests naturally yield lower capacity due to increased internal resistance.

500mA Mar 07, 2026 lowest current
4079mAh 102% of rated
1A Mar 06, 2026
3994mAh
2A Mar 07, 2026
3969mAh
3A Mar 07, 2026
3995mAh
4A Mar 07, 2026
3928mAh
5A Mar 07, 2026
3988mAh
10A Mar 07, 2026
3906mAh
15A Mar 08, 2026
4018mAh
20A Mar 08, 2026
4013mAh
20A Mar 08, 2026
4013mAh
25A Mar 08, 2026
4093mAh
30A Mar 08, 2026
4060mAh
Capacity vs Current
Weight Distribution (2 measurements)
Mdn
Avg
Min
67.99g
Median
68.24g
Average
68.24g
Max
68.49g
Std Dev
0.35g
Rated capacity 4 Ah
Cell voltage - Nominal 3.70 V
Charge cut-off voltage 4.20 V
Discharge cut-off voltage 2.50 V
Standard charge current 2 A
Maximum charge current 8 A
Maximum discharge current 45 A
Internal resistance ≤ 4 mΩ
Minimum charge temperature -10 °C
Maximum charge temperature 60 °C
Minimum discharge temperature -30 °C
Maximum discharge temperature 75 °C
Maximum discharge surface temperature ≤ 80 °C
Diameter (max) 21.31 mm
Height (max) 70.42 mm
Weight ~ 70 g