Hybrid solid-state cell with a 3D porous cathode structure
An electrochemical cell is provided, which includes a cathode comprising a three dimensional (3D) porous cathode structure, an anode, an electrolyte separator, comprised of a ceramic material, located between the cathode and the anode, and a cathode current collector, wherein the cathode is located between the cathode current collector and the electrolyte separator. The 3D porous cathode structure includes ionically conducting electrolyte strands extending through the cathode from the cathode current collector to the electrolyte separator, pores extending through the cathode from the cathode current collector to the electrolyte separator, and an electronically conducting network extending on sidewall surfaces of the pores from the cathode current collector to the electrolyte separator.
1. A method of forming an electrochemical cell including a cathode, an anode, an electrolyte separator, comprised of a ceramic material, located between the cathode and the anode, and a cathode current collector, wherein the cathode is located between the cathode current collector and the electrolyte separator, the method comprising:
forming a solid or semi-solid cathode comprising a cathode active material, an electrolyte for the charge transfer ion, and an electron conducting material; and
inserting the solid or semi-solid cathode into a cathode receptive space of the electrochemical cell, wherein the cathode is configured to precisely fit into the cathode receptive space,
wherein an upper portion of the cathode receptive space is bounded by the cathode current collector to contact an upper surface of the cathode, a lower portion of the cathode receptive space is bounded by the electrolyte separator, and side portions of the cathode receptive space are bounded by low-porosity ceramic walls.
2. The method of claim 1 , wherein the ceramic walls are comprised of solid-state electrolyte material.
3. The method of claim 1 , wherein the ceramic walls surround at least 60% of side portions of the cathode receptive space.
4. The method of claim 3 , wherein one side portion of the cathode receptive space includes an opening configured for inserting the cathode precisely into the cathode receptive space.
5. The method of claim 4 , further comprising providing a seal configured to seal the opening after the cathode has been inserted into the cathode receptive space.
6. The method of claim 5 , wherein the cathode is configured to completely fill the cathode receptive space.
7. The method of claim 5 , wherein the cathode current collector is comprised of at least one of a metal, a metal alloy, a conductive ceramic or a current conductive carbon-based material.
8. The method of claim 1 , wherein the cathode receptive space is devoid of ceramic electrolyte material.
9. A method of forming an electrochemical cell including a cathode, an anode, an electrolyte separator, comprised of a ceramic material, located between the cathode and the anode, and a cathode current collector, wherein the cathode is located between the cathode current collector and the electrolyte separator, the method comprising:
forming a solid or semi-solid cathode comprising a cathode active material, an electrolyte for the charge transfer ion, and an electron conducting material;
inserting the solid or semi-solid cathode into a cathode receptive space of the electrochemical cell, wherein the cathode is configured to precisely fit into the cathode receptive space; and
forming the anode, wherein the anode is a 3D porous anode structure formed by:
mixing a first precursor material and a second precursor together to form a mixture;
depositing the mixture as a layer in an anode receptive space where the 3D porous anode structure is to be formed; and
sintering the mixture to form the 3D porous anode structure with ionically conducting electrolyte strands extending through the anode from the anode current collector to the electrolyte separator, pores extending through the anode from the anode current collector to the electrolyte separator, and an electronically conducting network extending on sidewall surfaces of the pores in the anode from the anode current collector to the electrolyte separator,
wherein the second precursor material is a sacrificial material configured to decompose during formation of the pores of the anode by the sintering using the second precursor material, and the first precursor material is a material which forms a coating of the electronically conducting network on the sidewall surfaces of the pores of the anode formed by sintering the second precursor material.