According to an embodiment of the invention, a prismatic battery includes an electrode group 10 contained in a prismatic metal outer can. The electrode group 10 has a positive electrode substrate exposed part 11 at one end and a negative electrode substrate exposed part 12 at the other end. The positive and negative electrode substrate exposed parts 11 and 12 are bundled and welded to positive and negative electrode current collectors 13 and 14, respectively. The positive electrode substrate exposed part 11 and positive electrode current collector 13 and the negative electrode substrate exposed part 12 and negative electrode current collector 14 are covered with an insulating frame 16 having an angled U-shaped cross section and an angled U-shaped outline. It is therefore possible to provide a prismatic battery of a simple structure including an electrode group whose ends are covered with an easily manufactured insulating cover in which the battery's volume energy density is maintained and an internal short circuit is prevented.