| 摘要 |
PURPOSE:To prevent the separation of carbon powder, and improve a cycle service life by forming a negative electrode integrally of the carbon powder to store and release a cation by means of a binding agent composed of polyimide resin or polyvinyl formal resin. CONSTITUTION:A secondary battery (BA) is formed of a positive electrode 1, a negative electrode 2 and a separator 3 containing electrolyte. The negative electrode 2 is formed by carrying out drying and heat treatment after slurry formed by dispersing graphite powder capable of storing and releasing a cation in binding agent solution is applied to both surfaces of copper foil being a current collecting body by means of a doctor blade method. Solution formed by dissolving polyimide resin PI or polyvinyl formal resin PVF into N-methyl-2- pyrodoline NMP is used as the binding agent solution. In this way, when the PI or the PVF is used as a binding agent, binding performance between carbon powders and with current collecting body metal is improved, and a cycle service life can be lengthened. Since fluorine is not contained in the binding agent, even if a battery temperature is raised, the dangerousness of rupture or breakage can be prevented. |
