Can anyone explain this behaviour? I have a 16S pack of LFP cells and am using the diyBMS dynamic cell charging algorithm to charge the pack by reading the MQTT status messages in Node Red and then setting the appropriate charge voltage and current in my charger. It works nicely apart from when at high state of charge three of the cells show their voltage falling as SoC increases.
I can understand cell voltages increasing at different rates, but not why they should fall while charging.
These cells could do with top balancing and I do intend to do that, but I would like to understand why I see this.