More water use lead-acid batteries under more load??

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More water use lead-acid batteries under more load??

Post by eesiason » Mon Jul 22, 2019 7:09 pm

Anyone know if I would expect more water vapor if I'm pouring more kWhs through my batteries (off grid system)?

I recently put in mini-split ACs, and we run them when the sun is out and it's hot. All five of them at once can add up to 6,000 watts steady load. A "normal" day's use is about 20 kWh, a hot AC day is 60+ kWh. 17,000 watts of solar on four FM80s and two Radians, so plenty of capacity, just wondering if I need to peek in the batteries more often.

PS, I bought the Mr. Cool DIY mini-splits and they are awesome. On a DIY scale of 1 (easy) to 10 (hard) they are a 3-.

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Re: More water use lead-acid batteries under more load??

Post by Mike Curran » Wed Aug 14, 2019 5:06 pm

Any time you're charging your battery you'll see more gassing but it's mostly hydrogen, not water vapor. It sounds like your PV is more than adequate to support your loads so it's not clear (to me, anyway) that your battery is getting discharged then recharged, but if it is cycling, you'll definitely see more water use. FWIW - Mike

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Re: More water use lead-acid batteries under more load??

Post by larrywa » Fri Aug 16, 2019 11:51 am

Heat equals evaporation. When you force current through your batteries they heat up. If the ambient is hot, they evaporate more also.

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