ELECTRODE MATERIAL INCLUDING SILICON OXIDE AND SINGLE-WALLED CARBON NANOTUBES

1 . An electrode material for a lithium ion secondary battery, comprising:

an active material particles comprising an alkali metal or an alkali earth metal silicate;

a binder; and

single-walled carbon nanotubes (SWCNTs).

2 . The electrode material of claim 1 , wherein the electrode material comprises, based on a total weight of the electrode material:

at least about 80 wt % of a combination of graphite particles and the active material particles;

from about 1 wt % to about 5 wt % of a binder; and

from about 0.05 wt % to about 1 wt % of the single-walled carbon nanotubes (SWCNTs).

3 . The electrode material of claim 2 , wherein the SWCNTs have an average diameter ranging from about 0.5 nm to about 2.5 nm and an average length greater than 1 μm.

4 . The electrode material of claim 3 , wherein:

the SWCNTs have an I G /I D ratio or greater than about 5, as determined by Raman spectroscopy, and an average length ranging from about 10 μm to about 500 μm; and

the electrode material comprises from about 0.08 wt % to about 0.25 wt % of the SWCNTs.

5 . The electrode material of claim 2 , electrode material comprises from about 90 wt % to about 96.5 wt % of the combination of the graphite particles and the active material particles.

6 . The electrode material of claim 5 , 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.

7 . The electrode material of claim 6 , wherein the active material comprises:

from about 70 wt % to about 90 wt % of the graphite particles; and

from about 10 wt % to about 30 wt % of the active material particles.

8 . The electrode material of claim 6 , wherein:

the graphite particles have an average particle size ranging from about 2 μm to about 30 μm and a surface area ranging from about 0.5 m 2 /g to about 2.5 m 2 /g;

the active material particles have an average particle size ranging from about 1 μm to about 20 μm, and a surface area ranging from about 0.5 m 2 /g to about 30 m 2 /g; and

the graphite particles have a larger average particle size than the core particles.

9 . The electrode material of claim 2 , wherein the active material particles comprise:

a primary phase comprising Li 2 Si 2 O 5 , Li 2 SiO 3 , Li 4 SiO 4 , or any combination thereof; and

crystalline silicon domains dispersed in the primary phase.

10 . The electrode material of claim 9 , wherein the active material particles further comprise SiO x domains dispersed within the primary phase, where x ranges from 0.8 to 1.2.

11 . The electrode material of claim 9 , wherein:

the primary phase comprises Li 2 Si 2 O 5 ; and

the crystalline silicon domains have an average particles size less than 100 nm.

12 . The electrode material of claim 2 , wherein the active material particles comprise:

a primary phase comprising MgSiO 3 , Mg 2 SiO 4 , or a combination thereof; and

crystalline silicon domains dispersed within the primary phase.

13 . The electrode material of claim 2 , wherein the binder comprises polyvinylidene difluoride (PVDF), Na-carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), polyacrylic acid (PAA), lithium polyacrylate (LiPAA), or a combination thereof.

14 . The electrode material of claim 13 , wherein the binder comprises a combination of the CMC and SBR.

15 . The electrode material of claim 2 , wherein the electrode material further comprises from about 0.1 wt % to about 5 wt % of a conductive agent selected from carbon black, an electrically conductive polymer, a metallic powder, or any combination thereof.

16 . The electrode material of claim 15 , wherein the conductive agent comprises carbon black powder having a smaller average particle size than a particle size of the active material particles and the graphite particles.

17 . The electrode material of claim 1 , wherein the SWCNTs form a percolating network of conductive links between the active material particles.

18 . The electrode material of claim 1 , wherein the active material particles comprise a coating comprising turbostratic carbon having a Raman spectrum having:

a D band having a peak intensity (I D ) at wave number between 1330 cm −1 and 1360 cm −1 ;

a G band having a peak intensity (I G ) at wave number between 1580 cm −1 and 1600 cm −1 ; and

a 2D band having a peak intensity (I 2D ) at wave number between 2650 cm −1 and 2750 cm −1 , wherein:

a ratio of I D /I G ranges from greater than zero to about 1.1; and

a ratio of I 2D /I G ranges from about 0.4 to about 2.

19 . A lithium secondary battery comprising:

an anode comprising the electrode material of claim 1 ;

a separator;

a cathode; and

an electrolyte disposed between the anode and cathode.

20 . The battery of claim 19 , wherein the SWCNTs reduce electrical disconnection of the active material particles during charging and discharging of the lithium secondary battery.