| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium secondary battery superior in safety at the time of abnormal overheat, reliability against short circuit, and rapid charge and discharge characteristics. <P>SOLUTION: The lithium secondary battery has a positive electrode having a positive electrode mixture layer containing a positive electrode active material, a negative electrode having a negative electrode mixture layer containing as a negative electrode active material a lithium titanium complex oxide of a spinel type crystal structure or a ramsdellite type crystal structure, and a separator. The separator has a porous layer (I) which has mainly a resin (A) of which melting point is 80-140°C and/or a resin (B) which swells by absorbing a non-aqueous electrolytic liquid by heating and of which the degree of swelling increases according to temperature rise and a porous layer (II) containing mainly a filler of ≥150°C of heat resistant temperature. The positive electrode active material and the negative electrode active material have a primary particle size of ≤1 μm, and the thickness of the positive electrode mixture layer and the negative electrode mixture layer is ≤50 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT |
