SILICON ELECTROLYTE COMPOSITE PARTICLES, COMPOSITIONS AND USES IN LITHIUM ION BATTERIES
Porous particulates for use in lithium ion batteries are described. The porous materials include silicon active materials carried in a carbon matrix that includes a solid-electrolyte phase. The combined matrix of the carbon and solid-electrolyte carries silicon nanoparticles and conducts lithium ions and electrons. The manufacture and use are further described.
1 . A porous particulate for use in a lithium ion battery, the porous particulate comprising:
a porous heterogeneous matrix that includes a carbon phase, a solid-electrolyte phase, and a plurality of pores; and
a plurality of silicon nanoparticles, carried by and embedded in the porous heterogeneous matrix, and having at least a portion adjacent to the plurality of pores.
2 . The porous particulate of claim 1 , wherein the solid-electrolyte phase provides a lithium ion pathway from a surface of the particulate to the plurality of silicon nanoparticles.
3 . The porous particulate of claim 1 , wherein the solid-electrolyte phase is embedded in the carbon phase.
4 . The porous particulate of claim 1 , wherein the solid-electrolyte phase has a portion adjacent to the carbon phase.
5 . The porous particulate of claim 4 , wherein the silicon nanoparticles has a portion adjacent to the solid-electrolyte phase, and wherein the silicon nanoparticles are ionically connected to the solid-electrolyte phase.
6 . The porous particulate of claim 1 , wherein the carbon phase comprises carbon.
7 . The porous particulate of claim 1 further comprising a conductive carbon selected from the group consisting of carbon nanotubes, carbon nanofibers, graphene, graphene oxide, reduced graphene oxide, mesocarbon microbeads, or a mixture thereof.
8 . The porous particulate of claim 1 , wherein the solid-electrolyte phase is a perovskite; an anti-perovskite; NASICON type conductor; a garnet-like phase; an orthosilicate garnets; a thio-LISICON; a LGPS; an argyrodite; a layered sulfide; or a mixture thereof.
9 . The porous particulate of claim 1 , further comprising:
a particle electrical conductivity in a range of about 10 −3 to about 10 5 S/cm; or a particle ionic conductivity in a range of about 10 −5 to about 10 −1 S/cm.
10 . A process of preparing a porous particulate for use in a lithium ion battery, the process comprising:
forming a plurality of admixture microparticulates, having an average diameter of about 1 μm to about 100 μm, the admixture particulates include about 5 wt. % to about 80 wt. % (dry basis) of a carbon matrix precursor, about 5 wt. % to about 50 wt. % (dry basis) of a plurality of solid-electrolyte nanoparticles, and about 5 wt. % to about 90 wt. % (dry basis) of a plurality of silicon nanoparticles; and
reducing the carbon matrix precursor to provide a carbon phase.
11 . The process of claim 10 , further comprising:
after forming the plurality of admixture microparticulates, forming a solid-electrolyte phase from the solid-electrolyte nanoparticles.
12 . The process of claim 10 , wherein the process of reducing the carbon matrix precursor further includes forming a solid-electrolyte phase from the solid-electrolyte nanoparticles.
13 . The process of claim 10 , wherein reducing the carbon matrix precursor decreases a carbon concentration in the microparticulate and provides a porosity to the porous particulate.
14 . The process of claim 10 , wherein the plurality of admixture microparticulates are formed by spray drying a solution of an admixture of a carbon matrix precursor, a plurality of solid-electrolyte nanoparticles, and a plurality of silicon nanoparticles, or
wherein the plurality of admixture microparticulates are formed from a melt of an admixture of a carbon matrix precursor, a plurality of solid-electrolyte nanoparticles, and a plurality of silicon nanoparticles.
15 . The process of claim 10 , further comprising:
providing the plurality of solid-electrolyte nanoparticles by wet milling a solid-electrolyte macroparticle; or
providing the plurality of silicon nanoparticles by wet milling a silicon feed.
16 . The process of claim 10 , wherein the admixture particulates further include about 1 wt. % to about 20 wt. % (dry basis) of a conductive agent.
17 . A process of preparing a porous particulate for use in a lithium ion battery, the process comprising:
forming a plurality of admixture microparticulates, having an average diameter of about 1 μm to about 100 μm, the admixture particulates include about 5 wt. % to about 80 wt. % (dry basis) of a carbon matrix precursor, about 5 wt. % to about 50 wt. % (dry basis) of a plurality of solid-electrolyte nanoparticles, and about 5 wt. % to about 90 wt. % (dry basis) of a plurality of silicon nanoparticles; and
crosslinking the carbon matrix precursor to provide a carbon phase.
18 . The process of claim 17 , wherein the carbon matrix precursor is a polyacrylonitrile; and wherein crosslinking the carbon matrix precursor includes heating the admixture microparticulates to a temperature in a range of about 150° C. to about 350° C.
19 . The process of claim 17 , wherein the solid-electrolyte nanoparticles are solid-electrolyte nanowires.
20 . The process of claim 17 , wherein the admixture particulates further include about 1 wt. % to about 20 wt. % (dry basis) of a conductive agent.