Unfortunately the cycle life of lead-acid is TRASH to the point where in any country except for Canada, LiFePO4 or even Li-Ion are more cost effective due to their far better depth of discharge, cycle life and absolute lifespan.
Even a “deep cycle” cell can only withstand tens of actual deep cycles. To get the rated 200 cycles, you can only discharge to 80%, which makes your 10kWh bank effectively a 2kWh bank. Suddenly it doesn’t look cheap anymore, especially when you’re lucky to get 2 years out of it micro-cycling. Lead acid is only good for rare emergency deep discharges i.e. UPS usage and it’s even questionable there now due to time degradation putting a short limit on its lifespan.
Here in Canada we can’t get lithium in any form other than overpriced packs, so I do have a dying lead-acid bank that I’m hoping to limp out until we get better chemistries. It’s basically a big capacitor at this point. I compensate by dumping surplus solar power into my boiler or air conditioner depending on the season, and shedding all but essential loads during outages.
Unfortunately the cycle life of lead-acid is TRASH to the point where in any country except for Canada, LiFePO4 or even Li-Ion are more cost effective due to their far better depth of discharge, cycle life and absolute lifespan.
Even a “deep cycle” cell can only withstand tens of actual deep cycles. To get the rated 200 cycles, you can only discharge to 80%, which makes your 10kWh bank effectively a 2kWh bank. Suddenly it doesn’t look cheap anymore, especially when you’re lucky to get 2 years out of it micro-cycling. Lead acid is only good for rare emergency deep discharges i.e. UPS usage and it’s even questionable there now due to time degradation putting a short limit on its lifespan.
Here in Canada we can’t get lithium in any form other than overpriced packs, so I do have a dying lead-acid bank that I’m hoping to limp out until we get better chemistries. It’s basically a big capacitor at this point. I compensate by dumping surplus solar power into my boiler or air conditioner depending on the season, and shedding all but essential loads during outages.