ELECTROCHEMICAL CELLS WITH IMPROVED SPIRAL-WOUND ELECTRODE ASSEMBLY
A spiral-wound electrode assembly, an electrochemical cell with the spiral-wound electrode assembly, and a method of manufacturing an electrochemical cell with the spiral-wound electrode assembly are disclosed. The spiral-wound electrode assembly has a first electrode that has a first electrode active material, a leading edge and a trailing edge. The assembly has a second electrode that includes a second electrode active material, a leading edge and a trailing edge. A separator is located between the first electrode and the second electrode. The electrode assembly has an interfacial anode-to-cathode ratio of less than about 1.2. The first electrode, second electrode, and separator are wound so that the first electrode forms a layer at the outermost radius of the electrode assembly and so that the trailing edge of the second electrode extends past the trailing edge of the first electrode.
1 . A spiral-wound electrode assembly comprising:
a first electrode comprising a first electrode active material, a leading edge and a trailing edge;
a second electrode comprising a second electrode active material, a leading edge and a trailing edge;
a separator disposed between the first electrode and the second electrode;
the electrode assembly having an interfacial anode-to-cathode ratio of less than about 1.2; and
wherein the first electrode, the second electrode, and the separator are wound so that the first electrode forms a layer at the outermost radius of the electrode assembly and so that the trailing edge of the second electrode extends past the trailing edge of the first electrode.
2 . The spiral-wound electrode assembly of claim 1 wherein the first electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
3 . The spiral-wound electrode assembly of claim 1 wherein the second electrode active material comprises lithium.
4 . The spiral-wound electrode assembly of claim 1 wherein the first electrode active material comprises lithium.
5 . The spiral-wound electrode assembly of claim 1 wherein the second electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
6 . The spiral-wound electrode assembly of claim 1 wherein the trailing edge of the second electrode extends past the trailing edge of the first electrode by about 5 mm to about 20 mm.
7 . The spiral-wound electrode assembly of claim 1 wherein the second electrode comprises at least one tab that is affixed to the second electrode and
wherein the tab is positioned along the second electrode in a location extending past the trailing edge of the first electrode.
8 . An electrochemical cell comprising:
a housing having at least one open end;
an electrode assembly comprising
a first electrode comprising a first electrode active material, a leading edge, and a trailing edge;
a second electrode comprising a second electrode active material, a leading edge, and a trailing edge;
a separator disposed between the first electrode and the second electrode;
an electrolyte;
an end-cap assembly enclosing the at least one open end of the housing;
the electrode assembly has an interfacial anode-to-cathode ratio of less than about 1.2; and
wherein the first electrode, the second electrode, and the separator are wound so that the first electrode forms an outermost layer of the electrode assembly and so that the trailing edge of the second electrode extends past the trailing edge of the first electrode.
9 . The electrochemical cell of claim 8 wherein the first electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
10 . The electrochemical cell of claim 8 wherein the second electrode active material comprises lithium.
11 . The electrochemical cell of claim 8 wherein the first electrode active material comprises lithium.
12 . The electrochemical cell of claim 8 wherein the second electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
13 . The electrochemical cell of claim 8 wherein the trailing edge of the second electrode extends past the trailing edge of the first electrode by about 5 mm to about 20 mm.
14 . The electrochemical cell of claim 8 wherein the second electrode comprises at least one second electrode tab that is affixed to the second electrode and positioned along the second electrode in a location extending past the trailing edge of the first electrode.
15 . A method of manufacturing an electrode assembly comprising:
providing an electrode assembly comprising
a first electrode comprising a first electrode active material, a leading edge, and a trailing edge;
a second electrode comprising a second electrode active material, a leading edge, and a trailing edge;
a separator disposed between the first electrode and the second electrode;
winding the electrode assembly so that the first electrode forms an outermost layer of the electrode assembly and so that the trailing edge of the second electrode extends past the trailing edge of the first electrode wherein the electrode assembly has an interfacial anode-to-cathode ratio of less than about 1.2.
16 . The method of manufacturing an electrode assembly of claim 15 wherein the first electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
17 . The method of manufacturing an electrode assembly of claim 15 wherein the second electrode active material comprises lithium.
18 . The method of manufacturing an electrode assembly of claim 15 wherein the first electrode active material comprises lithium.
19 . The method of manufacturing an electrode assembly of claim 15 wherein the second electrode active material is selected from the group consisting of iron disulfide, iron sulfide, pyrite, and mixtures thereof.
20 . The method of manufacturing an electrode assembly of claim 15 wherein the trailing edge of the second electrode extends past the trailing edge of the first electrode by about 5 mm to about 20 mm.
21 . The method of manufacturing an electrode assembly of claim 15 wherein the second electrode comprises at least one second electrode tab that is affixed to the second electrode and
is positioned along the second electrode in a location extending past the trailing edge of the first electrode.