Methods of fabricating porous ceramic electrodes for solid state battery applications

Patent metadata

Field	Value
Publication number	US-11942622-B2
Application number	US-202117478509-A
Country	US
Kind code	B2
Filing date	Sep 17, 2021
Priority date	Sep 18, 2020
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

Compositions and methods for the fabrication of electrode and porous lithium-garnet electrolyte scaffolds for use in solid state batteries and other devices are provided. The methods produce porous structures using phase inversion or high shear compaction processes to fabricate a solid-state battery electrode material from LLZO electrolytes. Engineered electrode structures with a porous scaffold of solid electrolyte material provide lower interfacial resistances and a mechanical support for a thin solid electrode layer improving performance.

First claim

What is claimed is:

1. A method of forming a porous tape structure, the method comprising:
(a) forming a slurry of LLZO powder, a binder and a solvent;
(b) tape casting the slurry on a substrate to form a LLZO tape;
(c) applying a sacrificial layer on the LLZO tape to produce a bi-layered LLZO tape;
(d) immersing the bi-layered LLZO tape in water to induce solvent/water exchange;
(e) removing the bi-layered LLZO tape from the water and drying the bi-layered LLZO tape; and
(f) heating the bi-layered LLZO tape to remove the sacrificial layer and sinter the LLZO tape to produce a sintered LLZO tape;
(g) wherein a sintered LLZO tape with elongate pores with a length aligned perpendicularly to a top surface of the sintered LLZO tape is produced;
(h) wherein the water for solvent/water exchange further comprises a lithium salt selected from the group consisting of Li 2 CO 3 , LiCl, LiOH, LiNO 3 and Li 2 SO 4 ; and
(i) wherein lithium loss from solid materials during solvent exchange is inhibited.

2. The method of claim 1 , wherein the sacrificial layer is a material selected from the group of materials consisting of poly(methyl methacrylate) (PMMA), carbon, graphite, camphor, naphthalene and a polymer.

3. The method of claim 1 , wherein the slurry further comprises one or more selected from the group of Li 2 CO 3 , MgO, a dispersant and a wetting agent.

4. The method of claim 1 , further comprising:
removing binder from the dry bi-layered LLZO tape;
sintering the bi-layered LLZO tape after binder removal; and
infiltrating the sintered LLZO tape with lithium nickel manganese cobalt oxide (NMC).

Assignees

• Univ California

Inventors

• Tucker Michael
• Shen Fengyu

Classifications

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/664 Primary

  Ceramic materials · CPC title

• H01M4/801

  Sintered carriers · CPC title

• H01M10/058

  Construction or manufacture · CPC title

• H01M10/052

  Li-accumulators · CPC title