| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a wound type battery capable of suppressing deformation of the axial core and securing retention performance of an electrolytic solution. <P>SOLUTION: A lithium ion secondary battery 20 has an equilateral triangular battery container 7. An electrode group 6 in which a positive and a negative electrode plates are wound around via a separator is housed in the battery container 7. The axial core 1 is arranged at the center of the electrode group 6. The axial core 1 has the cross section crossing the longitudinal direction formed in an equilateral triangle. In the axial core 1, a protruding part in which three apexes are protruded to the outer peripheral direction from the center of the cross section is formed. In the axial core 1, distances from the center of the cross section to the apexes are respectively equal, and corresponds to the maximum distance from the center to the outer periphery. The electrode group 6 is infiltrated into a nonaqueous electrolytic solution injected into the battery container 7. When the positive and negative electrode plates and the separator are wound around the axial core 1, a winding pressure applied on the axial core 1 is dispersed to the apexes of three points. <P>COPYRIGHT: (C)2008,JPO&INPIT |
