Patent ID: 9431680
Filing Date: 2016-08-30
CPC Classification: H01M,H02J,Y02E,Y02P,Y10T

Claim Text:
1. An electric storage device, comprising: a housing; an electrode assembly in roll form housed in the housing, the electrode assembly being formed by winding a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode so as to have curved portions and linear portions continuous with the curved portions; current collectors housed in the housing, the current collectors being connected respectively to the positive electrode at one end of the electrode assembly in a direction of a winding axis of the electrode assembly and to the negative electrode at an other end of the electrode assembly in the direction of the winding axis of the electrode assembly; and an electrolyte solution housed in the housing, wherein the positive electrode includes a positive electrode substrate and a positive electrode mixture layer formed on the positive electrode substrate in a region excluding one end of the positive electrode substrate, wherein the negative electrode includes a negative electrode substrate and a negative electrode mixture layer formed on the negative electrode substrate in a region excluding an other end of the negative electrode substrate, wherein the positive electrode substrate has at its one end an unformed portion in which the positive electrode mixture layer is not formed, wherein the negative electrode substrate has at its other end an unformed portion in which the negative electrode mixture layer is not formed, wherein the current collectors are connected respectively to at least a part of the linear portions in the unformed portion of the positive electrode at the one end of the positive electrode and to at least part of the linear portions in the unformed portion of the negative electrode at the other end of the negative electrode, and wherein the one end in the positive electrode has a length greater than a winding length of the positive electrode, and/or the other end in the negative electrode has a length greater than a winding length of the negative electrode.