Li batteries at 48vdc
After much deliberation and questions, I'll likely be purchasing the 48v Lithium battery pack instead of 4-12v. I liked the idea of 12v batteries for weight and ease of handling, but the possible cel...
Forum Discussion
Hi all
I also have an Outback controller and LiFePO4 batteries.
For Li batteries do not use temperature compensation.
Set Bulk voltage will creep up to the setpoint then shift to absorb voltage. I have my controller set up to stay in absorption mode for 30 minutes.
What is the input voltage to your CC?
To address the 12 volt li bats in parallel, don’t let them get below about 80% DOD. I have my battery monitor set to alarm at 11.8 volts. That is a nice conservative number. The problem is that if a battery trys to shut of because a cell is low the voltage from the other batteries will keep turning that battery back on.
FWIW There are many variations in BMS design. Some companies spec that their 12 v batteries can only be connected in series, some say parallel only and still others either way. I have 4 100Ah Battleborn batteries in parallel and they are working well, But I have only had them for a few weeks. The microwave and inverter are happy now. The Trojan bats had developed too much sag under a heavy load. BTW I paid $824 each and free shipping for my Li bats.
Remember that you can’t charge Li if the battery is below freezing. So make provisions to keep them warm if you plan to use them in cold weather.
Gale
I also have an Outback controller and LiFePO4 batteries.
For Li batteries do not use temperature compensation.
Set Bulk voltage will creep up to the setpoint then shift to absorb voltage. I have my controller set up to stay in absorption mode for 30 minutes.
What is the input voltage to your CC?
To address the 12 volt li bats in parallel, don’t let them get below about 80% DOD. I have my battery monitor set to alarm at 11.8 volts. That is a nice conservative number. The problem is that if a battery trys to shut of because a cell is low the voltage from the other batteries will keep turning that battery back on.
FWIW There are many variations in BMS design. Some companies spec that their 12 v batteries can only be connected in series, some say parallel only and still others either way. I have 4 100Ah Battleborn batteries in parallel and they are working well, But I have only had them for a few weeks. The microwave and inverter are happy now. The Trojan bats had developed too much sag under a heavy load. BTW I paid $824 each and free shipping for my Li bats.
Remember that you can’t charge Li if the battery is below freezing. So make provisions to keep them warm if you plan to use them in cold weather.
Gale
