Patent ID: 8728665

Claim:
A negative electrode for a lithium ion secondary battery, comprising a negative electrode core member and a negative electrode mixture layer adhering to the negative electrode core member, wherein the negative electrode mixture layer includes active material particles with a graphite structure and a binder for bonding the active material particles, the binder includes a cellulose ether compound and rubber particles, the cellulose ether compound has a degree of etherification of 0.25 or more and 0.7 or less and an average degree of polymerization of 20 or more and 1200 or less, the negative electrode mixture layer contains remaining particles comprising a water-insoluble portion of the cellulose ether compound and having a mean particle size of 1 μm or more and 75 μm or less, and the bonding strength between the active material particles is 98 N/cm 2 or more.