Methods of preparing electrochemical cells
View Patent ↗Methods of preparing a cathode/separator assembly for use in electrochemical cells in which a protective coating layer, such as a single ion conducting layer, is coated on a temporary carrier substrate, a microporous separator layer is then coated on the protective coating layer, and a cathode active layer is then coated on the separator layer, prior to removing the temporary carrier substrate from the protective coating layer. Additional layers, including an edge insulating layer, a cathode current collector layer, an electrode insulating layer, an anode current collector layer, an anode layer such as a lithium metal layer, and an anode protective layer, such as a single ion conducting layer, may be applied subsequent to the coating step of the microporous separator layer. Also, methods of preparing electrochemical cells utilizing cathode/separator assemblies prepared by such methods, and cathode/separator assemblies and electrochemical cells prepared by such methods.
1. A method of preparing a cathode/separator assembly of an electrochemical cell, wherein said cathode/separator assembly comprises a cathode active layer and as microporous separator layer, said method comprising the steps of:
(a) coating a first protective coating layer on a temporary carrier substrate, wherein said first protective coating layer has a first surface in contact with said temporary carrier substrate and has a second surface on the side opposite from said temporary carrier substrate;
(b) coating a microporous separator layer on said second surface of said first protective coating layer, wherein said separator layer has a first surface in contact with said second surface of first protective coating layer and has a second surface on the side opposite from said first protective coating layer;
(c) coating a cathode active layer in a desired pattern on said second surface of said separator layer, wherein said cathode active layer has a first surface in contact with said second surface of said separator layer and has a second surface on the side opposite from said separator layer; and
(d) removing said temporary carrier substrate from said first surface of said first protective coating layer to form said cathode/separator assembly.
2. The method according to claim 1 , wherein said first protective coating layer is a single ion conducting layer.
3. The method according to claim 1 , wherein said first protective coating layer is an ionically conductive layer which is impervious to dimethoxyethane and 1,3-dioxolane, and combinations thereof.
4. The method according to claim 1 , wherein said first protective coating layer comprises a polymer selected from the group consisting of electrically conductive 30 polymers, ionically conductive polymers, sulfonated polymers, and hydrocarbon polymers.
5. The method according to claim 1 , wherein said first protective coating layer comprises an ionically conductive polymer.
6. The method according to claim 5 , wherein said ionically conductive polymer is a polydivinyl-poly(ethylene glycol).
7. The method according to claim 1 , wherein said first protective coating layer comprises a sulfonated polymer.
8. The method according to claim 7 , wherein said sulfonated polymer is a sulfonated polystyrene.
9. The method according to claim 1 , wherein said first protective coating layer comprises a microporous xerogel layer.
10. The method according to claim 9 , wherein said microporous xerogel layer comprises an organic polymer.
11. A method of preparing an electrochemical cell, said method comprising the steps of:
(a) providing a cathode/separator assembly prepared by a method comprising the steps of:
(i) coating a first protective coating layer on a temporary carrier substrate, wherein said first protective coating layer has a first surface in contact with said temporary carrier substrate and has a second surface on the side opposite from said temporary carrier substrate;
(ii) coating a microporous separator layer on said second surface of said first protective coating layer, wherein said separator layer has a first surface in contact with said second surface of said first protective coating layer and has a second surface on the side opposite from said first protective coating layer;
(iii) coating a cathode active layer in a desired pattern on said second surface of said separator layer, wherein said cathode active layer has a first surface in contact with said second surface of said separator layer and has a second surface on the side opposite from said separator layer; and
(iv) removing said temporary carrier substrate from said first surface of said first protective coating layer to form said cathode/separator assembly;
(b) providing an anode;
(c) providing a cathode current collector layer;
(d) providing an electrode insulating layer interposed between said anode and said cathode current collector layer; and,
(e) providing an electrolyte, wherein said electrolyte is contained in the pores of said separator layer; wherein said first surface of said first protective coating layer of said cathode/separator assembly and said anode are positioned in a face-to-face relationship and said second surface of said cathode active layer and said cathode current collector layer are positioned in a face-to-face relationship.
12. The method according to claim 11 , wherein said first protective coating is a single ion conducting layer.
13. The method according to claim 11 , wherein said first protective coating layer is an ionically conductive layer which is impervious to dimethoxyethane and 1,3-dioxolane, and combinations thereof.
14. The method according to claim 11 , wherein said first protective coating layer comprises a polymer selected from the group consisting of electrically conductive polymers, ionically conductive polymers, sulfonated polymers, and hydrocarbon polymers.
15. The method according to claim 11 , wherein said first protective coating layer comprises a microporous xerogel layer.
16. The method according to claim 15 , wherein said microporous xerogel layer comprises an organic polymer.
17. A method according to preparing an electrochemical cell, said method comprising the steps of:
(a) coating a first protective coating layer on a temporary carrier substrate, wherein said first protective coating layer has a first surface in contact with said temporary carrier substrate and has a second surface on the side opposite from said temporary carrier substrate;
(b) coating a microporous separator layer on said second surface of said is first protective coating layer, wherein said separator layer has a first surface in contact with said first protective coating layer and has a second surface on the side opposite from said first protective coating layer;
(c) coating a cathode active layer in a desired pattern on said second surface of said separator layer, wherein said cathode active layer has a first surface in contact with said second surface of said separator layer and has a second surface on the side opposite from said separator layer;
(d) depositing a cathode current collector layer in a desired pattern on said second surface of said cathode active layer, wherein said cathode current collector layer has a first surface in contact with said second surface of said cathode active layer and has a second surface on the side opposite from said cathode active layer;
(e) depositing an electrode insulating layer in a desired pattern on said second surface of said cathode current collector layer, wherein said electrode insulating layer has a first surface in contact with said second surface of said cathode current collector layer and has a second surface on the side opposite from said cathode current collector layer;
(f) depositing an anode current collector layer in a desired pattern on said second surface of said electrode insulating layer, wherein said anode current collector layer has a first surface in contact with said second surface of said electrode insulating layer and has a second surface on the side opposite from said electrode insulating layer;
(g) depositing an anode active material layer in a desired pattern on said second surface of said anode current collector layer, wherein said anode active material layer has a first surface in contact with said second surface of said anode current collector layer and has a second surface on the side opposite to said anode current collector layer;
(h) removing said temporary carrier substrate from said first surface of said first protective coating layer; and
(i) providing an electrolyte, wherein said electrolyte is contained in the pores of said separator layer.
18. The method according to claim 17 , wherein step (g) further comprises depositing an anode protective coating layer on said anode active material layer.
19. The method according to claim 18 , wherein said anode protective coating layer is a single ion conducting layer.