Dual battery setup for off grid solar

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Revlac Guru Joined: 31/12/2016 Location: Australia Posts: 1309	Posted: 09:07am 20 Jun 2026       I have read in a few place's that some run a LFP battery along side the Old Lead acid to extend the life of the Lead Acid by quite a margin, the LFP battery will do most of the work, when they get down the Lead acid takes over and carries on making them an ideal when the weather isn't great. Actually I have this setup in the shed but only for welding and other high surge stuff so have never run it flat to see the FLA batteries take over.   Quote   I was thinking of using a voltage controlled relay to switch the kilovacs, so that when one bank is fully charged then the other would be switched on to supply power and also be charged up. Probably something to measure the SOC on either pack and programmed to switch the relay.