| 摘要 |
PROBLEM TO BE SOLVED: To easily manufacture at a low cost, and increase capacity and cycle reversibility by using a mixed active material of silicon oxide and lithium- containing composite nitride in a negative electrode and a lithium-containing composite oxide capable of storing and releasing lithium in a positive electrode. SOLUTION: Li3-xMxN (M is transition metal, 0.2<x<=0.8) is used as lithium- containing nitride of an active material constituting a negative electrode together with a conductive material and a binder. Preferably, Co is used as the transition metal M, and SiO of lower oxide is used as silicon oxide. Although lithium is not automatically moved from the lithium-containing composite nitride having lithium releasing potential higher than lithium storage potential of the silicon oxide to the silicon oxide, the amount of lithium corresponding to the irreversible capacity is supplemented by charging/discharging. By this combination, the storage and releasing action of lithium is controlled, and a charging/ discharging voltage curve is made smooth. LiCoO2, LiNiO2, a composite of them, or LiMn2O4 is used in the positive electrode. |
