A battery of a vehicle includes a housing including: a lower portion that includes a plurality of separators extending vertically upward from a floor of the lower portion; and an upper portion that covers an opening of the lower portion and that is removable from the lower portion. The battery also includes: first and second terminals on the housing; third and fourth terminals on the housing; a plurality of individually housed batteries separated by the plurality of separators; a plurality of switches configured to selectively connect ones of the plurality of batteries to ones of the first, second, third, and fourth terminals; and a battery management module configured to control the plurality of switches.