Li ion customized battery packs 12V are rechargeable for energy storage
RoyPow Deep Cycle LiFePO4 Battery Pack 12V 6Ah Lithium Iron Phosphate Battery 3500 Cycles Rechargeable FiOS Drop in Replacement of SLA Battery, for RV/Camper, Kid Scooters, Fish Finder : Amazon.co.uk: Business, Industry
Tracer 12V 16Ah LiFePO4 Battery Pack with Grab Handle - Tracer Power