| 摘要 |
PURPOSE:To prevent the increase of the internal resistance and the reduction of the discharge performance by using low-molecular weight ethylene tetrafluoride resin powder for the binder of a positive electrode black mix and adding it at the specific ratio. CONSTITUTION:Low-molecular weight ethylene tetrafluoride resin powder is used for the binder of a positive electrode black mix 1 using MnO2 as a positive electrode active material, the low-molecular weight ethylene tetrafluoride resin powder 0.3-3wt.% is added to the whole weight of MnO2 and a conductive auxiliary. The above low-molecular weight ethylene tetrafluoride resin powder has little absorptivity of an electrolyte, the positive electrode black mix after molding is prevented from absorbing the electrolyte more than necessary and being swollen and softened to reduce the adherence with a positive electrode can, and the electron conductivity is not lowered in the positive electrode black mix. The sufficient electrolyte is secured around a negative electrode black mix 4, thereby the discharge performance is not reduced. When the addition of the low-molecular weight ethylene tetrafluoride resin powder is larger or smaller than the above ratio, the internal resistance is increased, and it is not desirable. |
