Lithium anodes for electrochemical cells
View Patent ↗Provided is an anode for use in electrochemical cells, wherein the anode active layer has a first layer comprising lithium metal and a multi-layer structure comprising single ion conducting layers and polymer layers in contact with the first layer comprising lithium metal or in contact with an intermediate protective layer, such as a temporary protective metal layer, on the surface of the lithium-containing first layer. Another aspect of the invention provides an anode active layer formed by the in-situ deposition of lithium vapor and a reactive gas. The anodes of the current invention are particularly useful in electrochemical cells comprising sulfur-containing cathode active materials, such as elemental sulfur.
1. A method of making an anode of an electrochemical cell in a vacuum chamber wherein the method comprises:
(a) providing a moving substrate;
(b) moving the substrate consecutively past a lithium vapor deposition source, wherein the source is characterized by a nozzle through which lithium vapor is emitted;
(c) providing reactive gaseous material adjacent to the lithium deposition nozzle; and
(d) condensing the lithium vapor of (b) on the substrate in presence of gaseous material to co-deposit a lithium anode active layer to form the anode.
2. The method of claim 1 , wherein the lithium vapor is condensed on the substrate by contacting the substrate with a cooled surface as the substrate passes through the vapor.
3. The method of claim 1 , wherein the thickness of the co-deposited lithium layer of the anode is from 2 μm to 100 μm.
4. The method of claim 1 , wherein the thickness of the co-deposited lithium layer of the anode is from 5 μm to 50 μm.
5. The method of claim 1 , wherein the substrate is selected from the group consisting of metal foils, polymer films, and metallized polymer films.
6. The method of claim 5 , wherein the polymer film is selected from the group consisting of films of polyethylene terephthalate, polyethylene naphthalate, 1,4-cyclohexanedimethylene terephthalate, polyethylene isophthalate, and polybutylene terephthalate.
7. The method of claim 1 , wherein the gaseous material is selected from one or more of the group consisting of carbon dioxide, acetylene, nitrogen, ethylene, sulfur dioxide, hydrocarbons, alkyl phosphate esters, alkyl sulfite esters, and alkyl sulfate esters.
8. The method of claim 1 , wherein the gaseous material is carbon dioxide.