> For the complete documentation index, see [llms.txt](https://badland-batteries.gitbook.io/b/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://badland-batteries.gitbook.io/b/12s-17000mah-15c-user-manual/cell-balancing.md).

# Cell Balancing

This battery has internal passive cell balancing. Balancing occurs at an average of about 2.2mA per cell.

**Top Balancing**

This must be turned on via a parameter and is off by default (see section “[Parameter Details](/b/12s-17000mah-15c-user-manual/parameter-details.md)”). If enabled, balancing will occur when the imbalance is 20mA or higher, but cells won’t balance below 4V. Balancing will occur even if the battery is not currently being charged. Top balancing will time out after 50 hours. If top balancing times out or succeeds, it will not occur again until discharge or Storage Mode occurs. Balancing will never occur when the battery is discharging in Storage Mode, or outside the safe discharging temperature range.

*Note:* Do not enable top balancing if your charger already handles cell balancing.

*Note:* If you do use the built-in top balancing, your charger must still monitor cell voltages and have voltage and current configured correctly.

**Major Imbalances**

The battery will try to balance out any major imbalances. This cannot be turned off. Balancing will start when the imbalance is 175mV or higher, but cells won’t balance below 3.5V. Balancing will never occur when the state of charge is below 30%, when outside the safe discharging temperature range, when discharging, or when in Storage Mode.