LiFePo4 lithium battery charging questions
TL DR – I have some questions related to charging 12V LiFePo4 lithium batteries: *How to best use my solar to charge batteries? *Assuming I usually keep the lithium batteries at a partial SOC, what ...
Forum Discussion
1) Charging a LiFePo4 is typically easier than FLA’s…Why??… Because unlike FLA chemistry, all a LiFePo4 needs is 14.X volts (not to exceed 14.6v), and do not require periodic equalizations…
2) It’s a good practice to occasionally charge to 100% SOC…Why??…This allows for both the occasional cell rebalancing and for shunt meter resynchronizations (to ensure meter accuracy)…Beyond that, there’s seldom a need to fully charge a LiFePo4 - Unlike FLA’s, LiFePo4’s are often capable of a near 0.0% DOD (depth of Discharge), but a more realistic working range of say somewheres between 90-20% SOC will help to extend battery life…
3) Upon a full recharge, it’s not advisable to continue to hold the battery at 14.X volts for extended periods…However, extended floating at say 13.6v (not to exceed) will do no harm, but is unnecessary…
4) Avoid charging an unheated battery when at or below 32d/f - however continued discharging is permissible down to about -4d/f…
5) LFP’s like to be long-term stored at or somewhere near the 50%SOC range…A true battery disconnect switch will serve you well…
In my view, IF your plan is to replace your two GC’s with one (or two?) 100a/h LiFePo4’s, then because of the LFP’s quicker recovery rate, your existing solar should often be able to meet most of your charging needs (quite naturally, ‘user experience’ will vary!)…JMO
3 tons
2) It’s a good practice to occasionally charge to 100% SOC…Why??…This allows for both the occasional cell rebalancing and for shunt meter resynchronizations (to ensure meter accuracy)…Beyond that, there’s seldom a need to fully charge a LiFePo4 - Unlike FLA’s, LiFePo4’s are often capable of a near 0.0% DOD (depth of Discharge), but a more realistic working range of say somewheres between 90-20% SOC will help to extend battery life…
3) Upon a full recharge, it’s not advisable to continue to hold the battery at 14.X volts for extended periods…However, extended floating at say 13.6v (not to exceed) will do no harm, but is unnecessary…
4) Avoid charging an unheated battery when at or below 32d/f - however continued discharging is permissible down to about -4d/f…
5) LFP’s like to be long-term stored at or somewhere near the 50%SOC range…A true battery disconnect switch will serve you well…
In my view, IF your plan is to replace your two GC’s with one (or two?) 100a/h LiFePo4’s, then because of the LFP’s quicker recovery rate, your existing solar should often be able to meet most of your charging needs (quite naturally, ‘user experience’ will vary!)…JMO
3 tons
