A solar charge controller may provide the info you are looking for, if not, these things provide a TON of info in battery boxes like the ones we have built. Watch K8MRD's YouTube video on all the things this meter can do and it's fairly cheap. https://www.amazon.com/dp/B07FN3VXH4/?coliid=I92AEN13XPMMS&colid=2S8ZYONFHTX5W&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
