Battery pack

A battery pack for supplying power to an electrical device, comprising a plastic housing having a housing wall comprising a plurality of wall sections, said housing wall forming a circumference wall;

• a plurality of battery cells inserted into said housing and situated next to one another, each battery cell having an outer circumference and so that said plurality of wall sections of said housing wall rest in a form-lock manner against the circumference surfaces of said battery cells, said wall sections of said housing and said circumference surfaces of said battery cells being complementarily shaped along at least one quarter of a circumference of said battery cells and wherein said housing has additional wall sections comprising an inner wall section and an outer wall section that both contract inward between said wall sections that rest against said circumference surfaces of said battery cells to adapt the circumference surfaces of said battery cells as closely as possible and to increase the external surface area of the housing.