| 摘要 |
PROBLEM TO BE SOLVED: To increase the discharge capacity without deteriorating the charging and discharging cycle characteristics by constituting a negative electrode active material from a composite of one kind or more components capable of storing lithium and graphite. SOLUTION: It is preferable to add one kind or more components of Ag having the theoretical discharge capacity of 500 Ah/kg or more, AgLix (1<x<=2.5), Si, Sn or SnOy (0<y<=2) to the total of a composite by 10 to 45 wt.%. It is preferable to set the mean grain diameter of the composite to about 1 to 2 μm. Therefore, a negative electrode active material having low change in volume by charging or discharging and having the large discharge capacity can be provided. Natural or artificial graphite is used, with the mean grain diameter preferably 15 to 25 μm, the graphite may be a mixture of a component capable of storing lithium or a reaction product and uniformly dispersed. A paste-like negative electrode material formed of the composite, binder and organic solvent is applied to a collector, dried and compressed as necessary, and a negative electrode is manufactured. |
