Method for battery tab attachment to a self-standing electrode
The present disclosure is directed to methods of securing battery tab structures to binderless, collectorless self-standing electrodes, comprising electrode active material and carbon nanotubes and no foil-based collector, and the resulting battery-tab secured electrodes. Such methods and the resulting battery tab-secured electrodes may facilitate the use of such composites in battery and power applications.
1. A self-standing electrode comprising:
a self-standing body comprising a composite material having electrode active material particles in a three-dimensional cross-linked network of carbon nanotubes, wherein the self-standing body includes a first face and a second face opposite the first face; and
a battery tab secured to the self-standing body that comprises:
a body;
a first leg extending from the body of the battery tab; and
a second leg extending from the body of the battery tab, wherein the self-standing electrode body is positioned between the first leg and the second leg, and the first leg contacts the first face of the self-standing body and the second leg contacts the second face of the self-standing body; and
wherein the first leg and the second leg sandwiching the electrode are mechanically fastened to each other.
2. The electrode of claim 1 , wherein the electrode active material is selected from graphite, hard carbon, silicon, silicon oxides, lithium metal oxides, lithium metal, and lithium iron phosphate.
3. The electrode of claim 1 , wherein the battery tab secured to the electrode comprises a single sheet of metal that is in contact with the first face and the second face of the electrode.
4. The electrode of claim 3 , wherein a first portion of the single sheet of metal that is in contact with the first face of the electrode is connected to a second portion of the single sheet of metal that is in contact with the second face of the electrode via one or more welds, rivets, staples, clamps or clips.
5. The electrode of claim 1 , wherein the battery tab secured to the electrode comprises two sheets of a metal that are in contact with the first face and the second face of the electrode, and that are connected to each other via one or more welds, rivets, staples, clamps or clips.
6. The self-standing electrode of claim 1 wherein the first leg covers less than 50% of the surface area of the first face of the self-standing body, and the second leg covers less than 50% of the surface area of the second face of the self-standing body.
7. The self-standing electrode of claim 6 wherein the first leg covers less than 33% of the surface area of the first face of the self-standing body, and the second leg covers less than 33% of the surface area of the second face of the self-standing body.
8. The self-standing electrode of claim 7 wherein the first leg covers less than 25% of the surface area of the first face of the self-standing body, and the second leg covers less than 25% of the surface area of the second face of the self-standing body.
9. The self-standing electrode of claim 1 wherein the first leg and the second leg each extends outward from the body of the battery tab, at least a first connection extends from the first leg and through the self-standing body to the second leg, and a first portion of the self-standing body is positioned between the body of the battery tab and the first connection.
10. The self-standing electrode of claim 9 wherein a second connection extends from the first leg and through the self-standing body to the second leg, and a second portion of the self-standing body is positioned between the first connection and the second connection.
11. The self-standing electrode of claim 10 wherein the first connection and the second connection are spot welds.
12. The self-standing electrode of claim 10 wherein the first connection and the second connection are ultrasonic welds.
13. The self-standing electrode of claim 10 , wherein the tab is attached directly to the self-standing body.
14. The self-standing electrode of claim 13 , wherein the tab is attached perpendicular to the edge of the main body of the electrode.
15. The self-standing electrode of claim 13 , wherein the tab is attached at an angle to the edge.
16. The self-standing electrode of claim 13 , wherein the tab comprises a single sheet of metal folded over the electrode.
17. The self-standing electrode of claim 13 , wherein the tab comprises two sheets, each placed on an opposite face of the electrode.
18. The self-standing electrode of claim 10 , wherein the tab is attached to a protrusion from the body, the protrusion being wider than the tab or of about the same width as the tab.
19. The self-standing electrode of claim 10 , wherein the tab is attached to a protrusion from the body, the protrusion being narrower than the tab.
20. The self-standing electrode of claim 10 , wherein the tab is folded over an edge of the main body of the electrode, or a protrusion therefrom, and the tab is secured by welds, rivets, staples, clamps, or clips.
21. The self-standing electrode of claim 10 , wherein each of the first leg and the second leg comprises two or more layers of metal foil.
22. The self-standing electrode of claim 10 , wherein the battery tab comprises two or more sheets of metal folded over the electrode.
23. The self-standing electrode of claim 1 , wherein the self-standing electrode body has an increased content of nanotubes on the first face and the second face of the self-standing electrode body.
24. The self-standing electrode of claim 1 , further comprising one or more carbon-coated metal foils placed between the first leg and the first face of the self-standing electrode body, and between the second leg and the second face of the self-standing electrode body.
25. The self-standing electrode of claim 24 , wherein the self-standing electrode body has an increased content of nanotubes on the first face of the self-standing electrode body and the second face of the self-standing electrode body.
26. A pouch cell battery comprising the self-standing electrode of claim 1 and an enclosure enclosing the self-standing electrode, the enclosure comprising two polymer-coated metal foils and a heat seal.
27. The pouch cell battery of claim 26 , wherein the first leg and the second leg each extends outward from the body of the battery tab, at least a first connection extends from the first leg and through the self-standing body to the second leg, and a first portion of the self-standing body is positioned between the body of the battery tab and the first connection.
28. A self-standing electrode comprising:
a body comprising a composite material having electrode active material particles in a three-dimensional cross-linked network of carbon nanotubes;
a member extending outward from the body; and
a battery tab secured to the member,
wherein the battery tab comprises a first sheet of metal and a second sheet of metal, and
wherein the first sheet of metal is in contact with a first face of the member, the second sheet of metal is in contact with a second face of the member, and the first sheet of metal is connected to the second sheet of metal.