US 12,482,904 B2
Electrical storage device
Daisuke Ito, Hyogo (JP); Yukihiro Mizonobe, Hyogo (JP); and Kensuke Watanabe, Hyogo (JP)
Assigned to SANYO ELECTRIC CO., LTD., Osaka (JP)
Appl. No. 17/779,389
Filed by SANYO Electric Co., Ltd., Osaka (JP)
PCT Filed Nov. 12, 2020, PCT No. PCT/JP2020/042221
§ 371(c)(1), (2) Date May 24, 2022,
PCT Pub. No. WO2021/106594, PCT Pub. Date Jun. 3, 2021.
Claims priority of application No. 2019-216054 (JP), filed on Nov. 29, 2019.
Prior Publication US 2022/0407191 A1, Dec. 22, 2022
Int. Cl. H01M 50/531 (2021.01); H01M 10/0525 (2010.01); H01M 50/107 (2021.01); H01M 50/188 (2021.01); H01M 50/547 (2021.01)
CPC H01M 50/531 (2021.01) [H01M 10/0525 (2013.01); H01M 50/107 (2021.01); H01M 50/188 (2021.01); H01M 50/547 (2021.01)] 6 Claims
OG exemplary drawing
 
1. An electrical storage device, comprising:
an electrode assembly in which positive electrodes and negative electrodes are alternately stacked with respective separators interposed between the positive electrodes and the negative electrodes;
a bottomed cylindrical outer can in which the electrode assembly is housed;
a sealing plate to which a positive electrode terminal and a negative electrode terminal are attached and that closes an opening of the outer can; and
a current breaking mechanism that is arranged closer to (1) the positive electrode terminal than the negative electrode terminal or (2) the negative electrode terminal than the positive electrode terminal on an inner surface of the sealing plate, wherein
the positive electrodes each include a respective positive electrode tab to be electrically connected with the positive electrode terminal,
the negative electrodes each include a respective negative electrode tab to be electrically connected with the negative electrode terminal,
the electrode assembly has a positive electrode tab group formed by stacking a plurality of the positive electrode tabs, and a negative electrode tab group formed by stacking a plurality of the negative electrode tabs, in which each of the tab groups functions as a spring for connecting the electrode assembly and the sealing plate,
among the positive tab group and the negative tab group, one tab group that is closer to the current breaking mechanism than the other tab group has a first spring constant greater than a second spring constant of the other tab group, and
a ratio (K/k) of the first spring constant K of the one tab group to the second spring constant k of the other tab group satisfies a relationship of 2.5≤K/k≤7.5.