Patent ID: 11870053
Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A secondary-battery negative electrode comprising:
a negative electrode collector; and
a negative electrode active material layer provided on a surface of the negative electrode collector,
wherein the negative electrode active material layer includes active material particles and amorphous carbon which covers at least parts of surfaces of the active material particles,
at least a part of a surface of the amorphous carbon is covered with a film having a lithium ion permeability,
the film contains an element M, and the element M is at least one selected from the group consisting of V, Nb, Ti, La, and Ta,
the amorphous carbon is a composite of carbon black and a fired product of pitch or tar, wherein a concentration of the carbon black in the amorphous carbon is 10 to 50 percent by mass,
wherein the film is formed on the surface of each of the active material particles with the amorphous carbon interposed between said film and said surface of each of the active material particles, and
wherein the active material particles are formed of a negative electrode active material selected from the group consisting of a silicon element, a silicon compound, and a silicon alloy.