Training My Seplos BMS

jassdhali · Mar 19, 2024

Hi,

Currently top balancing my battery pack before discharge.

The one thing I am unsure of is that the total current is still @ a minus figure.
Do I need to keep feeding the pack to get that to zero?

The cell deviation has gone from 274mV to what is above now at 4mV within 8 hours.
Currently running the inverter @ grid charge to feed battery.

Cycle is at 10 as I have had a few issues. I put down to my own stupidity & the fact I found the Seplos Active balancer acting weirdly (again may may been down to me)
Now running with a Neey 4a active balancer.

Please give me your thoughts, sure I am doing something wrong

Thanks for your time

johnb2713 · Mar 20, 2024

Down at 4mV youre fine, start using it.

jassdhali · Mar 20, 2024

johnb2713 said:
Down at 4mV youre fine, start using it.

Thanks John, will drain at the weekend, recharge & put into use.

Just one more query, probably overthinking things.
I know these packs with the BMS they drop slightly in SOC - but I have had mine totally isolated & the SOC dropped to 95% within 2 hours.

Is that normal ?

Thanks for your time

johnb2713 · Mar 20, 2024

When you say totally isolated, did you diconnect the BMS and Balancers too? If not they will be taking some power, LiFEP04's also seem to settle a little after charging, this may be what youre seeing.

jassdhali · Mar 20, 2024

johnb2713 said:
When you say totally isolated, did you diconnect the BMS and Balancers too? If not they will be taking some power, LiFEP04's also seem to settle a little after charging, this may be what youre seeing.

The breaker to connect to inverter is off, NEEY balancer is off.
I didnt disconnect the BMS, didn't think of doing this - I can have a go tomorrow, thanks

I understand the cells do settle a little, but this much.

Please see graph - just pulled off my inverter (the canbus is still connected)