The present disclosure is directed to energy storage systems for vehicles. In some aspects, the energy storage system may be used to power an electric automobile. The energy storage system may include a plurality of individual battery cells. The cells may be cylindrical and have a positive and negative terminal on the same side. The cells may be physically and/or electrically organized into bricks. The bricks may be physically and/or electrically organized into modules. The modules may be physically and/or electrically organized into strings. The strings may be physically and/or electrically organized into a pack. In some embodiments, packs, strings, modules and/or bricks may include flexible circuitry and/or may be liquid cooled.