Electric storage device

摘要

An electric storage device includes an electrode assembly, in which a positive electrode and a negative electrode in the shape of a sheet are wound with a separator sandwiched therebetween. The electrode assembly has a flat shape and includes a first flat portion and a second flat portion, which are opposed to each other, and a first curved portion and a second curved portion which connect end portions of the first and second flat portions together. One of the positive electrode and the negative electrode covers an inner-circumferential end portion of the other electrode and is disposed on an innermost circumference of the electrode assembly. An inner-circumferential end portion of the one of the electrodes causes an elastic force to act outwardly on the other electrode.

主权项

1. An electric storage device, comprising:
a current collector; and an electrode assembly, in which a positive electrode and a negative electrode in a shape of a sheet are wound with a separator sandwiched therebetween and connected to the current collector, wherein the electrode assembly has a flat shape and includes a first flat portion and a second flat portion, which are opposed to each other, and a first curved portion and a second curved portion which connect end portions of the first and second flat portions together, wherein one of electrodes of the positive electrode and the negative electrode covers an inner-circumferential end portion of an other electrode of the electrodes of the positive electrode and the negative electrode, and is disposed on an innermost circumference, wherein the one of the electrodes includes a protruding portion and a restraining portion, wherein the protruding portion protrudes from a side end of the other electrode in a direction along a winding center of the electrode assembly, wherein the restraining portion is formed by bundling areas of the protruding portion spaced from an inner-circumferential end portion of the one of the electrodes and is connected to the current collector, wherein the restraining portion includes a first restraining portion on one side of the protruding portion and a second restraining portion on an other side of the protruding portion with the winding center of the electrode assembly therebetween, wherein the first restraining portion restrains the one side of the protruding portion, wherein the second restraining portion restrains the other side of the protruding portion, wherein a leading-end edge of an inner-circumferential end portion of the other electrode is positioned in one of the first and second flat portions, and wherein an inner-circumferential end portion of the one of the electrodes is curved in a shape of a circular arc along an inner surface of one of the first and second curved portions to cause an elastic force to act outwardly on the other electrode.