how important is battery matching for parallel

Discussion in 'General Questions' started by little fridge, May 28, 2016.

  1. Hi new to solar, I did some 12 volt wind in the past with great success. So now I have a very small fridge in my little SUV the plan was to run it off a dedicated system with option to run off the SUV system while on the highway. I am having trouble getting my one optima AGM and one g35 lead acid battery to work together in parallel
    the fridge is I think 3.2ft. the fridge is working as advertised, when running it pulls between .75 and.9 amps 110vac. start amps is 6.0amps 110vac I have also confirmed with my nifty accumax meter and a good clamp meter a bunch of other specs, in rush current while on a 12v inverter is 79amps @12v. running amps on 12v inverter is about 6amps dc. this was a few days ago If I remember it was 63amp hours and or .53kw per 24 hours closed up in the SUV sitting in the sun.
    So I don't need that much power to run it.

    3 years ago I bought a super stupendous flexible solar panel that I thought was the do all end all , and it was new old stock then, so lets say over 5 year old technology. maybe somebody knows? it is a unisolar pvl-136 panel, USA made, but out of business, the nice thing is you really can roll it up and it fits in a 18" box.
    Then I also bought a few years ago a power bright 24 volt 400 watt inverter. the inverter is advertised as 800 watt start load, but will not run my little fridge, as I have now found out the start current is only rated for exactly 1 second, maybe a half a second too short to get the fridge started. fridge runs fine on a 10 year old 4oo watt 12v inverter. so I will be forced for now to solar charge at 24vdc, and then run the fridge at night with 12v parallel

    sorry for the long winded. intro. I have only tried 2 nights so far, but the AGM battery is hogging the load, and the group 35 is not doing much if anything. How important is it too have the 2 12v batteries be identical for good paralleling? how big do the link wires need to be between the 2 batts, remember the run load is only 6 amps I have the 2 batteries connected with 10 g wire, I think the 12 volt inverter has 9g wire going to the accumaxx meter



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