SECONDARY BATTERY AND METHOD FOR MANUFACTURING THE SAME

摘要

A secondary battery includes an laminated electrode in which positive electrode (1) and a negative electrode are arranged with a separator interposed therebetween. Positive electrode collector foil (3) is made of aluminum or an aluminum alloy. Positive electrode mixture layer (2) includes a positive electrode active material containing nickel and lithium. Protective layer (4) formed between positive electrode collector foil (3) and positive electrode mixture layer (2) includes a plurality of carbon particles (5). Carbon particles (5) are thin flakes which have principal plane (5a) and thickness (5b) orthogonal to principal plane (5a) and in which length L1 in one direction of principal plane (5a), length L2 in a direction orthogonal to the one direction within principal plane (5a), and length L3 in the direction of thickness (5b) satisfy the relationships of 5≧(L1/L2)≧1, (L1/L3)≧5, L2>L3, and L1≧4 μm. Within protective layer (4), principal plane (5a) intersects the thickness direction of protective layer (4). The average thickness of protective layer (4) is not less than 10 μm and not more than 100 μm.

主权项

1. A secondary battery comprising:
an laminated electrode in which a positive electrode including positive electrode collector foil and a positive electrode mixture layer and a negative electrode including negative electrode collector foil and a negative electrode mixture layer are arranged with a separator interposed therebetween, wherein: the positive electrode collector foil is made of aluminum or an aluminum alloy, the positive electrode mixture layer includes a positive electrode active material containing at least nickel and lithium, and a protective layer is formed between the positive electrode collector foil and the positive electrode mixture layer; the protective layer includes a plurality of carbon particles; the carbon particles are thin flakes which have a principal plane; the carbon particles are arranged so that within the protective layer, the principal plane intersects at least a thickness direction of the protective layer; and an average thickness of the protective layer is not less than 40 μm and not more than 100 μm.