Battery system for a motor vehicle

The battery system has a first casing component (21) that includes two sidewalls (22,23) and a base (24) extending between the first sidewall and the second sidewall. The height of the first sidewall is greater than the height of the second sidewall. A second casing component is operatively connected to the first casing component. Several cell holders (32) are fixedly connected to the first casing component at the base and the first sidewall, and are provided with several cells (31) fixedly connected to cell holders. The casing components are made of metal material or polymer material.