At Living Energy Farm, our conservationist design means we need very little stored electricity. We store electricity with nickel iron (NiFe) batteries, a very old, very durable battery technology. Nickel iron batteries tolerate tremedous swings of voltage input and discharge rates that would destroy any other kind of battery. These batteries are tremendously robust!
100 year old NiFe battery Old NiFe 
Homemade NiFe Modern NiFe set 100 year old battery works! Russian NiFe set
We now offer Iron Sun boxes, which have Nickel Iron batteries in them! For more information, please visit www.livingenergylights.com