METAL OXIDE COATED CORE PARTICLES FOR ANODE ELECTRODES AND METHOD OF MAKING THEREOF
An active material for a lithium ion secondary battery includes core particles containing SiO or M-SiO materials where M is selected from Al, B, Cu, Fe, K, Li, Mg, Na, Ni, Sn, Ti, Zn, Zr, Ca, V, Cr, Nb, Mo, W or any combination thereof, and a metal oxide shell coated on the core particles.
1 . An active material for a lithium ion secondary battery, comprising:
core particles comprising a SiO material or a M-SiO x material, wherein 0<x<1.2, and M is selected from Al, B, Ca, Cu, Fe, K, Li, Mg, Na, Ni, Sn, Ti, Zn, Zr, Ca, V, Cr, Nb, Mo, W or any combination thereof; and
a metal oxide shell located over the core particles.
2 . The active material of claim 1 , further comprising a carbon layer disposed between the metal oxide shell and the core particles, the carbon layer comprising pyrolyzed carbon, activated carbon, or carbon black.
3 . The active material of claim 1 , wherein the metal oxide shell covers at least 60% of the surface of the core particles.
4 . The active material of claim 1 , wherein, based on the total weight of the active material, the active material comprises:
from about 90 wt % to about 99 wt % of the core particles;
from about 0.01 wt % to about 10 wt % of the metal oxide shell; and
from 0 to about 5 wt % of a carbon material disposed between the metal oxide shell and the core particles.
5 . The active material of claim 4 , wherein, based on the total weight of the active material, the active material comprises:
from about 0.01 wt % to about 5 wt % of the metal oxide shell; and
from about 95 wt % to about 99.99 wt % of the core particles.
6 . The active material of claim 1 , wherein:
the core particles have an average particle size ranging from about 500 nanometers to about 20 microns;
the metal oxide shell has a thickness ranging from 1 nm to about 100 nm.
7 . The active material of claim 6 , wherein the metal oxide shell has a thickness ranging from 1 nm to about 5 nm.
8 . The active material of claim 1 , wherein the metal oxide shell comprises aluminum oxide, titanium oxide, zinc oxide or a combination thereof.
9 . The active material of claim 1 , wherein the metal oxide shell is formed by atomic layer deposition.
10 . The active material of claim 1 , wherein:
the core particles comprise M-SiO;
M comprises Li; and
the M-SiO comprises at least one of crystalline or amorphous silicon domains, lithiated silicon species domains, and silicon oxide domains comprising SiO y , where y ranges from 0.8 to 1.2.
11 . The active material of claim 10 , wherein:
the metal oxide shell comprises aluminum oxide, titanium oxide, zinc oxide, or a combination thereof; and
the M-SiO comprises lithiated silicon species domains comprising Li 2 Si 2 O 5 , Li 2 SiO 3 , Li 4 SiO 4 , or a combination thereof.
12 . The active material of claim 10 , wherein:
the metal oxide shell comprises aluminum oxide, titanium oxide, zinc oxide, or a combination thereof; and
the M-SiO comprises magnesium silicate species domains comprising MgSiO 3 , Mg 2 SiO 4 , or a combination thereof.
13 . The active material of claim 12 , wherein the M-SiO further comprises lithiated silicon species domains comprising Li 2 Si 2 O 5 , Li 2 SiO 3 , Li 4 SiO 4 , or a combination thereof in addition to the magnesium silicate species.
14 . The active material of claim 1 , wherein the core particles comprise at least one of crystalline or amorphous silicon domains, and silicon oxide domains comprising SiO y , where y ranges from 0.8 to 1.2.
15 . A lithium ion secondary battery, comprising:
an anode comprising an electrode material comprising the active material of claim 1 and a binder;
a separator;
a cathode; and
an electrolyte disposed between the anode and cathode.
16 . The lithium ion secondary battery of claim 15 , wherein the electrode material comprises, based on total weight of the active material:
from about 0.3 wt % to about 30 wt % of a binder;
from about 0.01 wt % to about 20 wt % of a conductive additive;
from about 0 wt % to about 97 wt % graphite particles; and
from about 3 wt % to about 100 wt % of the active material.
17 . The lithium ion secondary battery of claim 15 , wherein the active material comprises:
from about 50 wt % to about 95 wt % of the graphite particles; and
from about 5 wt % to about 50 wt % of the active material particles.
18 . The lithium ion secondary battery of claim 15 , wherein the binder comprises polyvinylidene difluoride (PVDF), Na-carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), polyacrylic acid (PAA), lithium polyacrylate (LiPAA), polyimide (PI), or a combination thereof.
19 . The lithium ion secondary battery of claim 15 , wherein the lithium ion battery is a solid state lithium battery comprising a solid-state anode, a solid state cathode, and a solid-state electrolyte.
20 . A method of forming an active material for a lithium ion secondary battery, comprising:
providing core particles comprising a SiO material or a M-SiO x material, wherein 0<x<1.2, and M is selected from Al, B, Ca, Cu, Fe, K, Li, Mg, Na, Ni, Sn, Ti, Zn, Zr, Ca, V, Cr, Nb, Mo, W or any combination thereof; and
forming a metal oxide shell over the core particles by atomic layer deposition.