To provide technique for a measure to counter vibration or shock in a battery pack for a hand-held electric tool in the batter pack for an electric tool.

The battery pack for the electric tool 101 has a battery pack 111 comprising a plurality of unit cells 113 arranged in parallel; a container 103 for housing the battery pack 111; and a buffer material 121 coming in contact with the wall surface 103a of the container 103 and the side surface of the battery pack 111 and interposed between the container 103 and the battery pack 111. The buffer material 121 has a first buffer zone and a second buffer zone made of an elastic material in a layer, and the elastic constant of the second buffer zone is made smaller than that of the first buffer zone. The transfer of vibration or shock to the battery pack is absorbed by the first buffer zone, and dimensional dispersion in buffer material installation spaces between the container 103 and the battery pack 111 is absorbed by the second buffer zone.

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