I have one 24v 110ah Lifepo4 plus 100ah lead acid (2x12v in series) The Lifepo4 holds the charge much better than the lead acid and should last much longer. Until last year only had lead acid batteries and they gradually lose capacity over 5-6 years so hoping the Lifepo4 lasts as long as the manufacturers claim. Some of the Chinese Lifepo4 manufacturers were claiming higher capacity than is true and there are varying quality of the cells and circuits used to make the Lifepo4s but if you get a good Lifepo4 it should be good for 10, 15 maybe 20 years? But yes as I am running 24/7 can only have a very small miner. Am now thinking after seeing your setup I want to get at least one bigger miner to have running in summer when I have a lot of surplus solar that the batteries cannot soak up. It does not matter too much if the miner is an older less efficient model if its cheap enough to buy it can still utilise the solar power that would otherwise not be used. Seems like theres probably a lot of older miners going quite cheap that are not economic to use ongrid but might still be good for offgrid when the sun shine use.
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Is the lifepo and lead acid together in a series? if so that lead acid is probably holding the other back.. They have very different charging curves. I think good Lifepo4 can easily last 10 years. But mixing chemistries isnt great for them.
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No I have the Lifepo4 as one circuit and the lead acid as a completely separate circuit. They both have 2 of the 4 300 watt PVs powering them. So they are standalone systems. Yes Lifepo4 and lead acid would not mix well in one circuit. The lead acid circuit powers a large 5000w inverter I use for power tools and backup in case the Lifepo4 circuit ever fails while the Lifepo4 circuit/battery powers 3000watt inverter which feeds the fridge and lights and laptop etc. This is because Im not as sure off the Lifepo4 handling heavy current loads as the lead acid...but the Lifepo4 is better with constant moderate loads and holding charge over night.
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Oh cool. That makes more sense. So are you offgrid completely?
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Some lifepo4 can start cars now. I do know they arent as good at large motor current draws though
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Yes the 110 ah lifepo4 is spose to be ok up to 100amp draw but the skilsaw motor probably draws a bit more than that when its starting up and working hard so safer to use the lead acid battery for that.
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In my experience most of these. Batteries will push more amps than they are rated for, no problem.
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