To solve such problems that there is an anxiety as for the scattering of an electrolyte when a fall and a tumble happen during a battery is transported and installed, so that a safety valve is opened by the impact, there is also an anxiety as for a safety valve carelessly or intentionally opened by a tool or the like during installation, and there is further an anxiety as for the scattering of battery contents when internal pressure rises due to overcharge or the like.

A lithium ion battery includes: a bottomed battery can in which an electrode group including a positive electrode plate and a negative electrode plate arranged via a separator is stored; and a battery lid including an opening formed therein and attached to the battery can. The lithium ion battery is provided with a resin film on one face of the battery can so as to cover the whole of the opening, the resin film being coated with an adhesive.