If needing a battery for backup power
Buy a lithium or stay without power really
to have a lead acid bank that lasts 3 years you have to buy 4x the lithium rating, ie you have to buy 4x100ah batteries for every 100ah lithium, and then you will most likely still throw them away after a few...
Disclaimer: All information is for educational purposes only. Always use a qualified electrician to alter,modify or add to the equipment. Electricity can kill. Notice something is wrong? Switch it off and phone the manufacturer for advice. I do not take any responsibility for information that is...