I have EDC "every day carry" batteries which cost me in the $10-$20 region, I bought them for all the family, sprinkled around and primarily related to "kids" (which my case = in their 20s) not having flat cellphones. I do not control them, they live whatever life they have.
I then have "home" batteries I maintain, these relate to doomsday type situations of tree falls and wait my turn, earthquake, etc. That is context of my question. The general domestic commodity trend is to USB, I have slowly over the last 5 years moved most power demands to USB (e.g. PC to laptop, to tablet, to cellphone) and so when I add up the phones + torches demand for an assumed worst-case scenario of 10 days of no electricity, I get to about 100Ah.
So I have about 100Ah of batteries, deliberately multiple devices to allow for device failure, deliberately spread around the home to allow for damage from whatever is the root cause (tree fell, etc).
What is the best maintenance strategy for these batteries? They are not aged by frequent reuse? So I should store them in cold? Should I drain and recharge them every few months?
So, best advice on battery maintenance?
I also keep solar, firewood and alcohol stoves, the fuel tends to get used most for BarB'Q and cosey livingroom fires, and camping trips, but I store all this at home deliberarately for the imagined worst case. So live for life but allow for the worst.