Battery pack

A battery pack for supplying current to an electric device, comprising:

• a plurality of battery cells;
• and
• at least one heat equalization element, located in an interstice between adjacent ones of the plurality of battery cells;
• wherein the at least one heat equalization element includes a plastic material having a thermal conductivity which is in the range of the maximum internal thermal conductivity of the plurality of battery cells,
• wherein the at least one heat equalization element does not include metal and is electrically nonconducting, and
• wherein the at least one heat equalization element, when heated, expands to press closely against adjacent ones of the plurality of battery cells, so that air gaps present between side faces of the at least one heat equalization element, whose faces contact circumferential faces of the battery cells are close, so as to improve heat transfer from the battery cells into the at least one heat equalization element to avoid overheating or debalancing of the battery cells;
• and wherein the at least one heat equalization element includes a plurality of heat equalization elements, each having a length corresponding to a length of the battery cells, and over a majority of the length, the cross-section is adapted to a shape of a nip between the battery cells, and wherein in a region of the adapted cross-section, the heat equalization elements are bounded essentially by four concave, partly cylindrical side faces, whose radii of curvature correspond to a radius of curvature of cylindrical circumferential faces of the battery cells.