NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

The nonaqueous electrolyte secondary battery of the present invention has a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution. The battery further has a porous heat-resistant layer provided between the separator and at least one of the positive electrode and the negative electrode, wherein the porous heat-resistant layer includes an inorganic filler and a binder. The inorganic filler included in the porous heat-resistant layer has a particle size distribution with two peaks, which are a first peak (P1) at a relatively small particle diameter and a second peak (P2) at a relatively large particle diameter. When the particle diameter of the first peak (P1) is D1 be and the particle diameter of the second peak (P2) is D2 being, the peak particle diameter ratio D1/D2 satisfies the condition 0.2≦D1/D2≦0.7.

主权项

1. A nonaqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution,
the battery further comprising a porous heat-resistant layer disposed between the separator and at least one of the positive electrode and the negative electrode, wherein the porous heat-resistant layer includes an inorganic filler and a binder, the inorganic filler included in the porous heat-resistant layer has a particle size distribution with two peaks, which are a first peak at a relatively small particle diameter and a second peak at a relatively large particle diameter, and when the particle diameter of the first peak is D1 and the particle diameter of the second peak is D2, the peak particle diameter ratio D1/D2 satisfies the condition 0.3≦D1/D2≦0.7.