US 12,735,582 B2 · Reticulated solid electrolyte separator

Abstract

This invention discloses a method of fabricating a reticulated solid electrolyte/separator (RSES) which is suitable both as electrolyte and separator in a solid state battery. The reticulated composite is produced by casting and drying of a slurry which exhibits a high yield stress (greater than 50 dyne/cm2) and comprised of a high MW resin dissolved in a solvent (having solution viscosity of higher than 100 cp at 5% in NMP at room temperature) and dispersed nanoparticles of solid electrolyte of high specific surface areas (i.e. greater than 1 m2/g, preferable greater than 10 m2/g) including but not limited to LLZO, LSP, or LIPON or derivatives thereof. This reticulated solid electrolyte/separator exhibits superior cycling properties and high ionic conductivity, resists lithium dendrite penetration, and maintains a high dimensional stability (less than 10% shrinking) at elevated temperatures (up to 140° C.). In addition, the present disclosure relates to electrochemical cells comprising such a reticulated film composite to act as both electrolyte and separator.

Claims20

Dependent claims

A solid electrolyte separator comprising a reticulated coating or film comprising a) a resin and b) nanoparticles

wherein the coating or film has an open porous structure, wherein the porous structure is from 10 vol. % to 80 vol % open pores, wherein the resin has a solution viscosity of from about 100 cp to 10,000 cp (at 5 wt % in NMP or at 2% water for water soluble polymers, at room temperature), wherein the nanoparticles are lithium based, electronically conductive and have a surface area of 1 to 1000 m2/g and wherein the average pore size is less than 500 nm.

A method of making a solid electrolyte separator, the method comprising the steps of

a) providing a resin dissolved in a solvent, wherein the polymer has molecular weight as measured by solution viscosity of from about 100 cp to 10000 cp (at 5 wt % in NMP or at 2 wt % in water for water soluble polymers, at room temperature),
b) providing nanoparticles, wherein the nanoparticles have surface area of 1 to 1000 m2/g,
c) combining the resin dissolved in a solvent and the nanoparticles to produce a slurry, wherein the weight percent of polymer to the weight percent of nanoparticle is from 80:20 to 5:95,
d) casting the slurry to form a coating or film,
e) drying the formed coating or film,
wherein the coating or film after drying has a porous structure, wherein the porous structure is from 10 vol % to 80 vol % open pores, and the average pore size is less than 500 nm,
wherein the slurry exhibits a yield stress of between 50 dyne/cm2 and 5000 dyne/cm2, and
wherein the solids content of the slurry is from 2 to 30 weight percent solids.

5 more elements

Dependencies are inferred from the claim text.

Reticulated solid electrolyte separator

Life of this patent

Reticulated solid electrolyte separator

Life of this patent

Abstract

Claims20