The Battery Cell Checker is a convenient way to monitor the charge status and health of any 2-6 cell (2-6s) lithium ion battery. It plugs into the battery’s balance plug (a white JST-XH connector) and tells you individual cell voltage, overall pack voltage, and the overall state-of-charge.
We use these in the field to check each battery before a dive and to sort out charged and discharged batteries afterwards.