Negative material for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using the negative material

摘要

The present invention relates to a nonaqueous electrolyte secondary battery comprising an anode (3), a cathode (2) and a nonaqueous electrolyte. The anode forming this battery includes composite particles having a carbon material included in a metallic material. As the metallic material, metal capable of electrochemically reacting with lithium in a nonaqueous electrolyte is included.

主权项

1. A negative electrode active material disposed on a surface of a current collector, said material comprising:
a first material composed only of carbon powder; and a second material composed of composite particles, each of said composite particles including a mixture of (a) a metallic material (b) a carbon material different from the first material, and (c) at least one metallic carbide compound selected from the group consisting of WC, W2C, TiC, ZrC, HfC, VC, NbC, TaC, MoC, V2C, Ta2C, Mo2C, Mn3C, Fe3C, Co3C, and Ni3C,
wherein,
said metallic material includes a metal to electrochemically react with lithium in a nonaqueous electrolyte,said carbon material is at least partially embedded within each of said composite particles of said second material so that at least a portion of said carbon material is exposed from said composite particles of said second material and another portion of said carbon material is buried in said composite particles of said second material such that the carbon material is not completely buried in the composite particles,said carbon material is present in an amount that is within the range of 0.1 wt % to 90 wt % inclusive relative to said metallic material, andsaid carbon material in each of said composite particles has fiber form.