| 摘要 |
PURPOSE:To retard self discharge and to lengthen charge-discharge cycle life by forming a negative electrode with lithium or alkali metal mainly comprising lithium supported, so as to be reduced on the side facing a separator on carbon obtained by baking organic compounds. CONSTITUTION:Phenol resin is baked in an atmosphere of nitrogen to carbonize it, and carbon powder obtained is mixed with polytetrafluoroethylene powder, then a mixture is pressed to form a pellet. The pellet is immersed in an electrolyte prepared by dissolving LiClO4 in propylene carbonate, then electrolysis is conducted using the pellet as an anode and metallic lithium as a cathode. In the electrolysis, current density in the early stage is reduced, then gradually increased with the advance of electrolysis. A large amount of lithium is supported on the side facing the metallic lithium compared with the back side. By forming a negative electrode 5 in which the content of active material is larger on the side facing a separator 4, self discharge is retarded and charge- discharge cycle life is lengthened. |
