| 摘要 |
PROBLEM TO BE SOLVED: To make a positive electrode of positive electrode active material, in which unreacted material remains, as before, and enable expected performance of the positive electrode active material to be sufficiently exhibited by using a butyral resin as a binder for the positive electrode. SOLUTION: A secondary battery comprises a positive electrode mixture, a negative electrode, a separator and a nonaqueous electrolyte. The positive electrode mixture includes mainly LiMO2 (wherein M represents a transition element), unreacted material in a preparing process, or a positive electrode active material containing a decomposed product as impurity, a conducting agent and a binder. The binder is made of a butyral resin. In this secondary battery, even if the unreacted material such as LiOH or Li2 CO3 is present in the positive electrode active material, the binder is made of polyvinyl butyral, thereby producing slurry for a positive electrode. An average molecular weight of polyvinyl butyral in the binder is desirably 4.0×10<4> . |
