Cells for cordless power tools
Tool packs are the hardest duty a small cylindrical cell sees: repeated current peaks, fast charge turnaround, and a housing that leaves little room for cooling.
What the pack actually demands
A professional tool pack pulls peak current measured in tens of amps for seconds at a time, then goes straight onto a fast charger. The binding constraints are therefore discharge current, charge acceptance, and the impedance growth that decides whether the cell still delivers that current after a few hundred cycles.
Which grade
Current-first 18650 cells in the 20–35 A class remain the default for 18 V and 21 V tool platforms. Where the tool has moved to a 21700 platform, 45 A class cells give the same peak with more runtime per cell.
What usually goes wrong
Specifying a cell on its peak rating without checking the temperature cut-off that rating depends on. A 35 A figure that assumes an 80 °C surface cut is not achievable inside a sealed tool housing with no thermal path.
Candidates in the catalogue
Cells on file that meet this duty profile
Selected with the same thresholds used on each model page, so a cell listed here and a model page pointing back at this application always agree. Figures are as published; models without a manufacturer data sheet are marked pending.
| Model | Brand | Format | Capacity | Cont. discharge | Max charge | Source |
|---|---|---|---|---|---|---|
| INR21700-P50B | Molicel | 21700 | 5,000 mAh | 60 A | 25 A | Datasheet |
| INR21700-P50S | Molicel | 21700 | 5,000 mAh | 60 A | 25 A | Datasheet |
| INR21700-P45B | Molicel | 21700 | 4,500 mAh | 45 A | 13.5 A | Datasheet |
| INR21700-P42A | Molicel | 21700 | 4,200 mAh | 45 A | — | Datasheet |
| INR18650-P22S | Molicel | 18650 | 2,200 mAh | 36 A | 4.0 A | Datasheet |
| INR18650-P30S | Molicel | 18650 | 3,000 mAh | 36 A | 6 A | Datasheet |
| INR21700-40T | Samsung SDI | 21700 | 4,000 mAh | 35 A | — | Pending |
| INR18650-P28A | Molicel | 18650 | 2,800 mAh | 35 A | 8.4 A | Datasheet |
| INR18650-P26A | Molicel | 18650 | 2,600 mAh | 35 A | 6.0 A | Datasheet |
| INR18650-P30B | Molicel | 18650 | 3,000 mAh | 30 A | 9 A | Datasheet |
| INR21700-50S | Samsung SDI | 21700 | 5,000 mAh | 25 A | 6 A | Pending |
| INR18650-25R | Samsung SDI | 18650 | 2,500 mAh | 20 A | — | Pending |
Where to go next
Formats that fit this application
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