Equalizing LifePo4 Batteries

[Dan1978]

I just purchased/installed 3 100AH LifePO4 batteries (SOK). They are hooked up to 320 watts solar and I'm using a Samlex Solar Charge Controller (Model scc-30ab). I reached out to Samlex to get input from them, essentially the charger works fine but one catch, it won't go into bulk/absorption unless the batteries fall below 12.4 volts for one hour. 12.4 volts for these batteries is quite low (~10%). So my thought if they get down near that SOC, is there any harm forcing equalization from the charge controller which will increase the charging voltage to 14.4 for 2 hours. I wouldn't do it regularly, just when batteries get low and can use the charge.

Here is the setting I'm using now on the charge controller, with equalization mode off so it can only be manually triggered. I reached out to Min at SOK who said no issues but curious if others have different opinions.


Thanks!

 

[mike95490]

I am concerned that your lead acid charger does not have the right voltage presets for your LFP batteries. What does your battery documentation say their max charge voltage is ?

 

[Dan1978]

I am concerned that your lead acid charger does not have the right voltage presets for your LFP batteries. What does your battery documentation say their max charge voltage is ?

Batteries are ok up to 14.6, as the equalization will only go to 14.4 would that cause an issue?

 

[mike95490]

Thats 2 tenths of a volt for margin. I guess it's ok. But there's something about holding/charging Li batteries at a high voltage for a long time. I think 5 minutes is enough, but they are your batteries and you have the manual.

 

[mikefitz]

, is there any harm forcing equalization from the charge controller which will increase the charging voltage to 14.4 for 2 hours.

Seems OK to me. If the batteries are low at 12.4 volts, then forcing a charge for 2 hours at a maximum of 30 amps will result in less that 50% charge for the 3 batteries.
Are you sure you need to do this as a float of 13.4 will hold the batteries in a high state of charge?

An alternative to the equalization mode would be to disconnect the solar, disconnect the battery, then reconnect battery then solar. Hopefully it will start a new charge cycle.

Save up for a Victron MPPT.

Mike