BikeMaster Lithium Ion Battery DLFP-51913 Most advanced high-power lithium iron phosphate battery technology from BikeMaster Ultra high cranking amps from a superweight battery which makes it 1/3 the weight of a lead acid battery Cylindrical cell with energy storage welding technology for higher output Built-in charge and equalizing protection board which prevents battery from over-charging Remarkably low self-discharge or extended storage periods up to one year