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.