| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology to improve the production efficiency of a lithium ion secondary battery.SOLUTION: A lithium ion secondary battery comprises a battery structure 18 where a plurality of pairs of a positive electrode 6 and a negative electrode 4 disposed on opposite sides of a separator 5 is laminated. A negative electrode collector 20X of the negative electrode 4X is provided with a first through hole 30. A positive electrode collector 26 of the positive electrode 6 is provided with a second through hole 32. A negative electrode collector 20Y of the negative electrode 4Y is provided with a third through hole 34. The percentage of the opening area of the negative electrode collector 20X of the negative electrode 4X disposed at the end of the battery structure 18 in the lamination direction is higher than the percentage of the opening area of the negative electrode collector 20Y of the negative electrode 4Y and the percentage of the opening area of the positive electrode collector 26 of the positive electrode 6. |
