Lithium battery cell with protective membrane having a garnet like structure
Li/air battery cells are configurable to achieve very high energy density. The cells include a protected a lithium metal or alloy anode and an aqueous catholyte in a cathode compartment. In addition to the aqueous catholyte, components of the cathode compartment include an air cathode (e.g., oxygen electrode) and a variety of other possible elements.
1. An electrochemical device comprising:
a first electrode comprising a lithium anode;
a protective membrane architecture comprising a lithium ion conducting oxide having a garnet like structure; and
a second electrode in ionic communication with the first electrode via the protective membrane architecture.
2. The device of claim 1 , wherein the lithium ion conducting oxide is selected from the group consisting of Li 5 La 3 M 2 O 12 , where M=Nb or Ta.
3. The device of claim 1 , wherein the lithium ion conducting oxide is Li 5 La 3 Nb 2 O 12 .
4. The device of claim 1 , wherein the lithium ion conducting oxide is Li 5 La 3 Ta 2 O 12 .
5. The device of claim 1 wherein the lithium anode is selected from the group consisting of lithium metal, a lithium intercalation material and a lithium alloy.
6. A battery cell, comprising:
a protected anode, comprising,
a lithium anode having a first surface and a second surface,
a protective membrane architecture on at least the first surface of the anode,
a cathode compartment comprising a cathode for reducing molecular oxygen and an aqueous catholyte comprising water, an active first substance material comprising an active first salt dissolved therein, and a second non-active lithium salt different than the active first salt, wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 50%; and,
wherein the protective membrane architecture comprises one or more materials configured to provide a first membrane surface chemically compatible with the alkali metal anode in contact with the anode, and a second membrane surface substantially impervious to and chemically compatible with the components of the cathode compartment.
7. The cell of claim 6 , wherein the active first salt is selected from the group consisting of a halide, nitrate or ammonium salt.
8. The cell of claim 7 , wherein the concentration of the active first salt is at least 2 Molar.
9. The cell of claim 7 , wherein the active first salt is AlCl 3 , NH 4 NO 3 , NH 4 Br, NH 4 Cl, NH 4 I or NH 4 CNS.
10. The cell of claim 6 , wherein the active first salt and the non-active second salt have a common salt component.
11. The cell of claim 10 , wherein the common salt component is a halogen or nitrate.
12. The cell of claim 11 , wherein the active first salt and the non-active second salt are both halides but do not have a common halogen anion.
13. The cell of claim 6 , wherein the catholyte, prior to initial discharge, has a halide or nitrate concentration of at least 6 Molar and a Li concentration of at least 2 Molar.
14. The cell of claim 6 , wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 15%.
15. The cell of claim 6 , wherein the catholyte is a saturated salt solution.
16. A battery cell, comprising:
a protected anode, comprising,
a lithium anode having a first surface and a second surface,
a protective membrane architecture on at least the first surface of the anode,
a cathode compartment, prior to initial discharge, comprising:
a cathode for reducing molecular oxygen;
an aqueous catholyte;
a solid phase active substance material, water soluble and in contact with the aqueous catholyte; and
a reservoir disposed between the cathode and the protected anode, the reservoir comprising a porous solid structure chemically compatible with the catholyte and chemically and electrochemically compatible with the cathode, at least a portion of the surface or the pore structure of the solid porous reservoir structure substantially covered or containing and/or in contact with the solid phase active substance material;
wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 50%; and
wherein the protective membrane architecture comprises one or more materials configured to provide a first membrane surface chemically compatible with the alkali metal anode in contact with the anode, and a second membrane surface substantially impervious to and chemically compatible with the components of the cathode compartment.
17. The cell of claim 16 , wherein the solid phase active substance material is a solid phase hygroscopic active salt in contact with the catholyte.
18. The cell of claim 17 , wherein the solid phase active salt comprises a halogen, a nitrate or an ammonium salt.
19. The cell of claim 16 , wherein the active solid phase active substance material is in the form of a compact.
20. A battery cell, comprising:
a protected anode, comprising,
a lithium metal anode having a first surface and a second surface,
a protective membrane architecture on at least the first surface of the anode,
a cathode compartment comprising a cathode for reducing molecular oxygen, an aqueous catholyte, and a porous inorganic solid reservoir structure disposed between the protected anode and the cathode, wherein a portion of the porous inorganic solid is electronically conductive;
wherein sufficient catholyte is present in the reservoir pores to maintain sufficient ionic communication between the cathode and the anode;
wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 50%; and
wherein the protective membrane architecture comprises one or more materials configured to provide a first membrane surface chemically compatible with the alkali metal anode in contact with the anode, and a second membrane surface substantially impervious to and chemically compatible with the components of the cathode compartment.
21. The cell of claim 20 , wherein the solid porous reservoir structure comprises a carbonaceous porous structure.
22. A battery cell, comprising:
a protected anode, comprising,
a lithium metal anode having a first surface and a second surface,
a protective membrane architecture on at least the first surface of the anode,
a cathode compartment comprising a cathode for reducing molecular oxygen, an active aqueous catholyte, and a solid porous reservoir structure;
wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 50%; and,
wherein the protective membrane architecture comprises one or more materials configured to provide a first membrane surface chemically compatible with the alkali metal anode in contact with the anode, and a second membrane surface substantially impervious to and chemically compatible with the components of the cathode compartment; and
wherein one or more of the cathode and the solid porous reservoir structure is configured to expand during cell discharge.
23. The cell of claim 22 , wherein the solid porous reservoir is or comprises an elastic polymeric porous structure.
24. A battery cell, comprising:
a protected anode, comprising,
a lithium metal anode having a first surface and a second surface,
a protective membrane architecture on at least the first surface of the anode,
a cathode compartment comprising a cathode for reducing molecular oxygen, an aqueous catholyte, and a hydrogel reservoir structure;
wherein the catholyte, prior to initial discharge, has an equilibrium relative humidity of less than 50%; and,
wherein the protective membrane architecture comprises one or more materials configured to provide a first membrane surface chemically compatible with the alkali metal anode in contact with the anode, and a second membrane surface substantially impervious to and chemically compatible with the components of the cathode compartment.