CN3791 Li-Ion charger board compatibility with 2S battery packs

TECHNICAL SUPPORT Batteries & Power
1

Customer:

I have recently purchased some solar charge controllers CN3791. I had assumed that these detect the voltage of the connected battery but I cannot find any information in English to confirm this. I intend to use a 2S2P battery pack, so 7.2V. Is this compatible with the CN3791?

Originally submitted via email support on 18 July 2025. Migrated to the forum for community visibility.

2

Soldered Support:

Unfortunately, this Li-Ion charger board only supports charging 1S cells, with a maximum voltage of 4.2V. As such, it’s not suitable for the intended use.