Battery unit comprising built-in temperature control means

The invention relates to a battery unit () essentially comprising a plurality of cells, a housing () receiving and surrounding said cells, and means () for regulating the temperature of said cells by circulation of a heat-transfer fluid. Said battery unit () is characterised in that the housing () comprises, at least in a bottom region on which the cells are arranged, at least one, preferentially several, heat exchange zones for heat exchange between said cells and the heat-transfer fluid, said at least one zone being built into the structure of said housing (), preferentially in the wall thereof.