A battery pack includes: a battery including a battery element covered with a packaging member, the battery element including a positive electrode and a negative electrode which are spirally wound together or stacked on one another through a separator; a protection circuit board for the battery; and a covering material collectively covering the battery and the protection circuit board. The covering material includes a shape-retaining polymer. The shape-retaining polymer contains an insulating curable polyurethane resin including polyol and polyisocyanate.