NEGATIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY, PRODUCING METHOD THEREFOR, AND LITHIUM ION SECONDARY BATTERY USING THE NEGATIVE ELECTRODE

摘要

A negative electrode for a lithium ion battery with high capacity, excellent cycle performance, and discharge performance at high load. In the negative electrode for a lithium ion secondary battery including a current collector and an active material layer carried on the current collector: the active material layer includes silicon, and an element M incapable of forming an alloy with lithium; the proportion of element M is higher in a first side contacting the current collector than in a second side opposite to the first side, in the thickness direction of the active material layer; the element M is different from the element forming the current collector; and the active material layer does not include a binder.