BATTERY PACK

Safety is ensured by suppressing adverse effect in which exhaust gas at high temperature ejected from an exhaust valve of a battery is ejected to the outside through a mating surface of a case. A battery pack includes battery cell (2) having exhaust valve (2a) that opens when internal pressure exceeds set pressure, and case (1) that houses battery cell (2). Case (1) includes multiple case units (10) molded with plastic, multiple case units (10) being coupled with mating surfaces (4) to dispose battery cell (2) inside case (1), and heat-resistant material (3) disposed inside mating surfaces (4) of respective multiple case units (10), heat-resistant material (3) blocking gap (5) between mating surfaces (4).