Patent ID: 9673453
Date: 2017-06-06
CPC Classifications: H01M,Y02E,Y02P,Y10T

Claim:
1. A method for manufacturing a lithium ion secondary battery, comprising: a binder coating step of coating a slurry-form binder containing a binding agent on a collector; a mixture supplying step of supplying a negative electrode mixture containing graphite, so as to be superposed on the slurry-form binder before the slurry-form binder having been coated on the collector in the binder coating step is dried; a magnetic field applying step of applying a magnetic field having magnetic lines of force pointing in a direction orthogonal to a plane of the collector having been supplied with the negative electrode mixture, to the negative electrode mixture having been supplied to the collector in the mixture supplying step; a convection generating step of generating convection in the negative electrode mixture by applying heat to the negative electrode mixture to which the magnetic field has been applied in the magnetic field applying step; wherein the slurry-form binder to be coated in the binder coating step has a viscosity (Adv) satisfying 50 mPa·sec≦Adv≦2000 mPa·sec; the slurry-form binder to be coated in the binder coating step has a thickness (At) satisfying 1.0 μm≦At≦4.5 μm; the magnetic field applying step and the convection generating step are performed at the same timing, thereby to apply a magnetic field having magnetic lines of force pointing in a direction orthogonal to the collector, to the negative electrode mixture having been coated on the collector in the mixture supplying step, and to generate convention by applying heat to the negative electrode mixture; in the convection generating step, generating convection in the negative electrode mixture by applying heat to the negative electrode mixture by a convection generating device comprising a drying furnace, and in the magnetic field applying step, applying the magnetic field having magnetic lines of force pointing in a direction orthogonal to the collector, to the negative electrode mixture by a magnetic field applying device disposed in the convection generating device.