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The truth about lead acid vs lithium ion in solar power

You are better off with lead acid batteries, if you follow this:First how not to do it, and make the lithium ion win:

If you buy 10, 000 watt hours of lithium ion vs lead acid, and discharge them 80 percent:Lithium ion, Price: $7 - 10, 000 dollars, life span 2000 cycles. Lead acid batteries: Price, $500, life span 200 cycles.

The above is the example everyone uses, and it is myopic and stupid. HERE IS REALITY:

If you instead spend $1000 for your lead acid batteries for 20, 000 watt hours, and discharge them 50 percent, they last 1, 000 cycles.
If you spend 1, 500 for your lead acid batteries, for 30, 000 watt hours, and discharge them 30 - 35 percent, they last 2000 charge cycles, (and still deliver near rated capacity)
If you spend $2000 for your lead acid batteries, for 40, 000 watt hours, and discharge them 20- 25 percent (which will equal what you would have taken from the lithium ion if you used them as rated), the lead acid will last 5, 000 charge cycles. They will vastly out last the lithium ion, for 20 - 30 percent of the price. If you managed them properly and always kept them topped off with water, there's a chance they will last until you are dead.

There are maximum age ratings for lead acid, at about 10 years, best case scenario. But if you use them super gently as I stated above, had them at a reasonable temperature not higher than 80 F overall and removed from your bank the ones that went bad early, I'd bet you'd still have an actual 10, 000 watt hours available after 20 years if you started out with 40, 000 and at that point you could still match the 10, 000 watt hour lithium ion that got sent in for refurbishing "12 years ago". And if you ever, at any point actually needed the extra capacity for a cold spell or whatever, and did draw the bank down 80 percent once, you'd get almost 4x the power the lithium ion would have delivered and it would not make any difference in the life span that you would notice at all.

I really think the people who rip lead acid are either after a buck or never thought of stressing them a LOT less by simply adding more because they are cheap enough to do that, if you maintain them properly they are by far the better deal, several times over.

You will have to additionally pay for shelves to put them on, and wires to wire them all in, but if you did it yourself you'd get that done for $200. For a prime setup you would need 20 - 30 large deep cycle batteries costing about $70 -90 each (120 amp hours I use as an example is cheaper than the biggest you can get, you could get that for $70). I'd make sure the cases were white plastic so a light placed behind them would shine through and let you see the electrolyte level without pulling the vent caps off. That would make maintenance many times easier, and that battery bank, costing (up to) $2000 will still be going quite nicely after 10 years.

I am really tired of people pushing lithium ion, for serious stationary storage they are simply "not there" yet, lead acid makes a huge pile of sense.

How to fail with lead acid: Get 2 120 amp hour deep cycles, laugh about how you're gonna do it for $150, hook them up to a 400 watt solar panel that would overcharge them from totally dead before 2 PM and then drain them down to zero every day, and then cry when they crap out in 6 months. Obviously there are people that would do that, and they become the examples that are used to cause people to fork over 7 plus thousand for a battery designed to survive the worst idiot.

A viable lead acid setup will have 12 120 amp hour batteries at a minimum and cost at least $800 DIY. A good one will have 20 batteries, a great one 30, if all are doing the same job of keeping an average house going.

IMPORTANT: Make sure the the solar panels that are in such a system can keep up with demand and then some. It will do no good to add more batteries if your solar panels can't top them off daily. Your charger should be shutting off before sunset daily.