Electrochemical device and manufacturing method thereof

摘要

Provide an electrochemical device offering a large capacity per current collector and a low internal resistance, which is also easy to assemble. Provided is a laminated sheet body 16S by inserting a negative-electrode continuous body 11BW between an adjacent pair of first current collectors 12a, 12a with their first current collector main units 12a1 connected together, and also between an adjacent pair of first current collectors 12a, 12a with their first tabs 12a2 connected together, with respect to a plurality of positive electrodes 11A arranged in the width direction apart from each other, after which the negative-electrode continuous body of the laminated sheet body is cut to the unit width dimension of an element to obtain a plurality of laminated bodies 16.

主权项

1. An electrochemical device having a separator between positive and negative electrodes, wherein:
the positive electrode has: a first positive-electrode current collector; a second positive-electrode current collector; and a third positive-electrode current collector; each including a positive-electrode current collector main unit of rectangular sheet shape having an active material layer formed at least on one side, as well as a positive-electrode tab formed partly on a top side of the applicable positive-electrode current collector main unit; wherein the second positive-electrode current collector is electrically connected to the first positive-electrode current collector via each positive-electrode tab, and the positive-electrode current collector main unit of the second positive-electrode current collector is positioned in a manner facing the back side of the positive-electrode current collector main unit of the first positive-electrode current collector; wherein the third positive-electrode current collector is electrically connected to the first positive-electrode current collector via a bottom side thereof opposite to the top side of each positive-electrode current collector main unit along which the positive-electrode tab is formed, said bottom side having a connection part having a width which is the same as a width of each positive-electrode current collector main unit, and the positive-electrode current collector main unit of the third positive-electrode current collector is positioned in a manner facing the front side of the positive-electrode current collector main unit of the first positive-electrode current collector; the negative electrode has: a first negative-electrode current collector; and a second negative-electrode current collector; each including a negative-electrode current collector main unit of rectangular sheet shape having an active material layer formed on both sides, as well as a negative-electrode tab formed partly on a top side of the applicable negative-electrode current collector main unit; wherein the first negative-electrode current collector is positioned between the first positive-electrode current collector and second positive-electrode current collector; wherein the second negative-electrode current collector is positioned between the first positive-electrode current collector and third positive-electrode current collector and electrically connected to the first negative-electrode current collector solely via each negative-electrode tab; and the separator is constituted by: a first separator having a first sheet area covering the front side of the negative-electrode current collector main unit of the first negative-electrode current collector, a second sheet area covering the back side, and a connection part connecting the first sheet area and second sheet area; and a second separator having a first sheet area covering the front side of the negative-electrode current collector main unit of the second negative-electrode current collector, a second sheet area covering the back side, and a connection part connecting the first sheet area and second sheet area.