CATHOLYTE MANAGEMENT FOR A SOLID-STATE SEPARATOR
Provided herein are electrochemical cells that include a seal impermeable to a liquid electrolyte and that is bonded to a solid-state Li ion-conducting electrolyte in a manner that effectively isolates and protects a Li metal negative electrode from exposure to either, or both, a liquid electrolyte or a gel electrolyte used as a catholyte in the positive electrode. Some of the electrochemical cells include a series of electrochemical stacks, which may be stacked in a variety of configurations including configurations that share a Li metal negative electrode.
1 . An electrochemical stack, comprising a solid-state electrolyte;
a positive electrode comprising a liquid electrolyte or a gel electrolyte;
a positive electrode current collector; and
a seal impermeable to the liquid electrolyte or the gel electrolyte that bonds to the positive electrode current collector and to the solid-state electrolyte.
2 . The electrochemical stack of claim 1 , wherein the seal contains the liquid electrolyte or the gel electrolyte in the positive electrode.
3 . The electrochemical stack of claim 1 or 2 , wherein the solid-state electrolyte is impermeable to the liquid electrolyte or the gel electrolyte.
4 . The electrochemical stack of any one of claims 1 - 3 , wherein the solid-state electrolyte has tapered edges.
5 . An electrochemical cell comprising at least one or more electrochemical stacks of any one of claims 1 - 4 .
6 . An electrochemical cell, comprising:
a container;
at least one electrochemical stack in the container, the electrochemical stack comprising at least:
a solid-state electrolyte;
a positive electrode comprising a liquid electrolyte or a gel electrolyte;
a positive electrode current collector; and
a seal impermeable to the liquid electrolyte or the gel electrolyte that bonds to the positive electrode current collector and to the solid-state electrolyte, wherein the seal is not bonded to the container.
7 . The electrochemical cell of claim 6 , wherein the seal comprises a material selected from the group consisting of polyisobutylene (PIB), polyether ether ketone (PEEK), polypropylene (PP), a polyolefin, and combinations thereof.
8 . The electrochemical cell of claim 6 or 7 , wherein the seal comprises a top layer and a bottom layer, and wherein the top layer of the seal and the bottom layer of the seal comprise the same material.
9 . The electrochemical cell of claim 8 , wherein the seal further comprises a middle layer, and wherein the middle layer of the seal is a different material than the top layer or bottom layer.
10 . The electrochemical cell of claim 8 or 9 , wherein the top layer and the bottom layer comprise PIB.
11 . A battery comprising at least one electrochemical cell of any one of claims 6 - 10 .
12 . The electrochemical cell of any one of claims 6 - 11 , wherein the seal has a hardness of 30-150 durometer.
13 . A device comprising an electrochemical cell of any one of claim 6 - 12 .
14 . A method of making an electrochemical cell, comprising:
providing a positive electrode current collector and an electrochemical cell stack on a substrate;
applying a seal material on to the positive electrode current collector;
wherein the electrochemical stack comprises:
a solid-state electrolyte;
a positive electrode comprising a liquid electrolyte or a gel electrolyte;
wherein the seal material is impermeable to the liquid electrolyte or the gel electrolyte, and wherein the seal material bonds to the positive electrode current collector and to the solid-state electrolyte;
enclosing the cell stack within a pressure ring; and
applying at least 3 pounds per square inch (PSI) to the electrochemical cell.
15 . The method of claim 14 , wherein the electrochemical stack further comprises a negative electrode current collector.
16 . The method of claim 14 or 15 , wherein the electrochemical stack further comprises a lithium metal negative electrode.
17 . The method of any one of claims 14 - 16 , comprising applying the seal material after assembling the electrochemical stack.
18 . The method of any one of claims 14 - 17 , wherein applying the seal material comprises spraying the seal material.
19 . The method of any one of claims 14 - 17 , wherein applying the seal material comprises coating the seal material.
20 . The method of any one of claims 14 - 17 , wherein applying the seal material is comprises injection molding.
21 . The method of claim 20 , wherein the injection molding occurs at a pressure lower than atmospheric pressure.
22 . The method of claim 21 , wherein the injection molding occurs at a minimum pressure of 0.00001 atm.
23 . The method of any one of claims 14 - 22 , wherein the seal material is in contact with the solid-state electrolyte.
24 . The method of any one of claims 14 - 23 , wherein the seal material is selected from the group consisting of polyisobutylene (PIB), polyether ether ketone (PEEK), polypropylene, a polyolefin, and combinations thereof.
25 . The method of any one of claims 14 - 23 , wherein the seal material is selected from the group consisting of polyisobutylene (PIB), polyether ether ketone (PEEK), and combinations thereof.
26 . The method of any one of claims 14 - 25 , wherein the pressure ring comprises polyether ether ketone (PEEK).
27 . The method of any one of claims 14 - 26 , comprising heating the substrate to at least 50° C.
28 . A method of making an electrochemical cell, comprising:
providing a positive electrode current collector on a substrate;
applying a seal material on the positive electrode current collector;
providing a pressure ring;
providing an electrochemical stack on the seal material and within the pressure ring,
wherein the electrochemical stack comprises:
a solid-state electrolyte;
a positive electrode comprising a liquid electrolyte or a gel electrolyte; and
wherein the seal material is impermeable to the liquid electrolyte or the gel electrolyte that bonds to the positive electrode current collector and to the solid-state electrolyte; and
applying at least 3 pounds per square inch (PSI) to the electrochemical cell.
29 . The method of claim 28 , wherein the pressure ring comprises polyether ether ketone (PEEK).
30 . The method of claim 28 or 29 , wherein the electrochemical stack further comprises a negative electrode current collector.
31 . The method of any one of claims 28 - 30 , wherein the electrochemical stack further comprises a lithium metal negative electrode.