| 摘要 |
PROBLEM TO BE SOLVED: To reduce the temperature difference of a plurality of secondary batteries in the secondary batteries arranged in a vertical direction.SOLUTION: A battery pack 30 comprises a counter weight 31 for balancing a load mounted on a fork. The counter weight 31 includes a rectangular weight part 32, and a planar weight body 33 that is protruded in a thickness direction of the weight part 32 from one end of a transverse direction of the weight part 32 and extends over the other end of a longitudinal direction from one end of the longitudinal direction of the weight part 32. The weight body 33 has a thick part 34 whose thickness gradually increases from upward of the longitudinal direction to downward of the longitudinal direction. At an opposite region A, an upper side region A2 has a heat capacity larger than that of a lower region A1. |
