LiFePO4 - 100Amph Lithium Iron Phosphate Battery - Sterling Power
LiFePO4 12V (nominal) 100Ah 25 deg C Lithium Deep cycle. These cost £278.40 on the Sterling Power website which is what I paid. I have 2 for sale. The specs are below Can be put in series 12V | 24V | 36V | 48V.