NEGATIVE ELECTRODE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY USING THE SAME

摘要

Provided is a negative electrode for a non-aqueous electrolyte secondary battery, capable of improving the energy density and the cycle characteristics of the battery without lowering the initial charge/discharge efficiency of the battery. This negative electrode includes a negative electrode active material including a silicon oxide represented by SiOx and carbon material. A proportion of a mass of the silicon oxide relative to a total mass of the silicon oxide and the carbon material: y satisfies 0.03≦y≦0.3. A difference between a theoretical capacity density of the negative electrode active material and a charge capacity density of the negative electrode active material when a cutoff voltage is 5 mV relative to lithium metal: ΔC (mAhg−1) satisfies L=ΔC/100 and 6y≦L≦12y+0.2.

主权项

1. A negative electrode for a non-aqueous electrolyte secondary battery,
the negative electrode including a negative electrode active material including a silicon oxide represented by SiOx (0.5≦x<1.5) and a carbon material, a proportion of a mass of the silicon oxide relative to a total mass of the silicon oxide and the carbon material: y satisfying 0.03≦y≦0.3, and a difference between a theoretical capacity density of the negative electrode active material and a charge capacity density of the negative electrode active material when a cutoff voltage is 5 mV relative to lithium metal: ΔC (mAhg−1) satisfying L=ΔC/100 and 6y≦L≦12y+0.2.