| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce the amount of a binder while suppressing degradation in battery characteristic. <P>SOLUTION: A negative electrode active material layer contains a negative electrode active material and a binder. The binder is a mixture of a polyacrylonitrile resin having an electrolyte-swelling property of 200 wt.% or lower and a B-type viscosity of 1000 mPa s or higher, and a polyvinylidene fluoride having an electrolyte-swelling property of 200 wt.% or higher and a B-type viscosity of 1000 mPa s or higher. The polyacrylonitrile resin comprises a homopolymer of (meth-) acrylonitrile; a copolymer of (meth-) acrylonitrile and other monomers, or a modified product from the copolymer. The mixing ratio of the polyacrylonitrile resin to the polyvinylidene fluoride is preferably in the range of 90:10 to 10:90 by weight, and the total amount of addition of the binder obtained by mixing the polyacrylonitrile resin and the polyvinylidene fluoride is preferably in the range of 1 to 5 wt.% of a negative electrode mixture. <P>COPYRIGHT: (C)2012,JPO&INPIT |
