Battery pack, battery pack cell swell detection system, power storage device, and automobile

摘要

PROBLEM TO BE SOLVED: To provide a battery pack in which expansion of any one of cells within the battery pack can be detected.SOLUTION: A battery pack of an embodiment includes: a plurality of cells of a first group; a plurality of cells of a second group; a first conductor provided on main walls of battery cans of the cells of a first group; a second conductor provided to main walls of battery cans of the cells of a second group; and a detection part for detecting conductivity between the first conductor and the second conductor. The cells of a first group and the cells of a second group are arranged alternately, the first conductor faces the second conductor, and the cells arranged alternately have a gap formed therebetween.