SECONDARY BATTERY

摘要

Disclosed is a lithium ion secondary battery using a high-energy negative electrode, which is capable of achieving long operation life. Specifically disclosed is a secondary battery which comprises: an electrode element wherein a positive electrode and a negative electrode are arranged so as to face each other; an electrolyte solution; and a case for housing the electrode element and the electrolyte solution. The negative electrode is obtained by binding a negative electrode active material, which contains (a) a carbon material that is capable of absorbing and desorbing lithium ions, (b) a metal that can be alloyed with lithium and (c) a metal oxide that is capable of absorbing and desorbing lithium ions, with a negative electrode collector by means of a negative electrode binder. The electrolyte solution contains a liquid medium, which does not easily generate carbon dioxide, at a concentration of 10-80 vol%.