Lithium batteries utilizing nanoporous separator layers
Provided are methods of preparing lithium batteries comprising a separator/electrode assembly having one or more current collector layers interposed between first and second electrode layers of the same polarity, wherein the first electrode layer is coated or laminated overlying a separator layer and the separator/electrode assembly is interleaved with an electrode comprising a current collector layer interposed between two electrode layers of opposite polarity to said first and second electrodes.
1. A method of making a multilayer structure for use in a lithium battery, the method comprising the steps of:
(a) providing a porous separator;
(b) placing a first electrode layer of a first polarity directly on a first portion of the porous separator;
(c) placing second electrode layer of the same polarity directly on a second portion of the porous separator;
(d) placing at least one current collector layer directly on the first electrode layer; and
(e) placing the second electrode layer on the one or more current collector layers on a side opposite to said first electrode layer.
2. The method of claim 1 , further comprising the step of interleaving the multilayer structure with an electrode assembly comprising a current collector layer interposed between two electrode layers of an opposite polarity to the first and second electrode layers to form a dry cell.
3. The method of claim 2 , further comprising the steps of
(h) enclosing the dry cell in a casing and
(i) filling the cell with electrolyte and sealing the casing to form a lithium battery.
4. The method of claim 1 , wherein the one or more current collector layers comprises a metal layer.
5. The method of claim 4 , wherein an edge connection of the one or more current collector layers comprises metal tabbing.
6. The method of claim 4 , wherein the thickness of the metal layer is less than 3 microns.
7. The method of claim 1 , wherein the first and second electrode layers of a first polarity are anode layers.
8. The method of claim 7 , wherein the anode layers comprise lithium metal.
9. The method of claim 7 , wherein the one or more current collector layers comprises a metal layer selected from the group consisting of a copper layer and a nickel layer.
10. The method of claim 2 , wherein the first and second electrode layers of a first polarity are cathode layers.
11. The method of claim 10 , wherein the one or more current collector layers comprises an aluminum layer.
12. The method of claim 11 , wherein the two electrode layers of an opposite polarity comprise lithium metal.
13. The method of claim 1 , wherein the first and second electrode layers are coated directly on the porous separator from a pigment dispersion comprising an organic solvent or water.
14. The method of claim 1 , wherein the porous separator comprises inorganic oxide particles in an amount greater than 30% by weight.
15. The method of claim 1 , wherein there are no pores larger than 0.2 microns in diameter in the porous separator.
16. The method of claim 1 , wherein the separator comprises a xerogel layer.
17. The method of claim 1 , wherein the porous separator has a thickness of less than 9 microns.
18. The method of claim 1 , wherein the porous separator comprises aluminum boehmite.
19. The method of claim 1 , wherein the porous separator is a heat resistant separator with dimensional stability at 200° C.
20. The method of claim 1 , wherein the porous separator comprises pores having an average pore diameter of less than 0.1 microns.
21. The method of claim 1 , wherein the current collector layers have a thickness of about 3 μm or less.
22. The method of claim 1 , wherein the current collector layers have a thickness from about 0.5 μm to about 1.5 μm.
23. A multilayer structure for use in a lithium battery comprising:
(a) a porous separator;
(b) a first electrode layer of a first polarity directly on a first portion of the porous separator;
(c) a second electrode layer of the same polarity directly on a second portion of the porous separator; and
(d) one or more current collector layers directly on the first electrode layer to make a separator/electrode stack, wherein
(e) the second electrode layer is also on the one or more current collector layers on a side opposite to the first electrode layer.