| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which achieves the durability and overcharge resistance at a high level.SOLUTION: A nonaqueous electrolyte secondary battery comprises: a wound electrode body; and a nonaqueous electrolyte. When the sum of the average thicknesses a1 and a2 of the positive electrode active material layers 14, and the average thicknesses a3 and a4 of negative electrode active material layers 24 is represented by "A", and the sum of the average thickness b1 of a positive electrode collector 12, and the average thickness b2 of a negative electrode current collector 22 is represented by "B", the wound electrode body satisfies the following expression: 4.78≤(A/B)≤6.69. The negative electrode active material layer 24 includes a graphite-based material as a negative electrode active material, and the number X (ions/cm) of charge carrier ions per cubic centimeter of the negative electrode active material layer is given as follows. X=Pore volume Va(L) in the negative electrode active material layer×(Concentration L(mol/L) of charge carrier ions in the nonaqueous electrolyte)×Avogadro constant NA(/mol)/Apparent volume Vt(cm) of the negative electrode active material layer. Then, X is 2.65×10to 3.83×10. |
