21700 battery holders accept the larger 21700 lithium cell (21mm x 70mm) used in Tesla EVs, high-performance flashlights, and vaping devices. Higher capacity than 18650 at the cost of larger size.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | Positive | Cell positive terminal | PWR |
| 2 | Negative | Cell negative terminal | GND |