| 摘要 |
Disclosed is a Si-based alloy anode material for lithium ion secondary batteries. This Si-based alloy anode material comprises an alloy phase composed of a Si principal phase comprising Si and a compound phase comprising two or more elements. The two or more elements comprise a first additional element A being at least one selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb and Mg and a low-melting second additional element B being at least one selected from the group consisting of S, Se, Te, Sn, In, Ga, Pb, Bi, Zn, Al and Ag. This compound phase comprises (i) a first compound phase comprising Si and the first additional element A; a second compound phase comprising the first additional element A and the second additional element B; and one or both of a third compound phase comprising two or more of the second additional elements B and a single phase of the second additional element B, or, alternatively, comprises (ii) a compound phase comprising Si and the first additional element A; and one or both of a compound phase comprising two or more of the second additional elements B and a single phase of the second additional element B. The Si principal phase has an average minor axis width of 4µm or less. This anode material of the present invention enables provision of secondary batteries having satisfactory performances both in charge-discharge capacity and cycle life. |
