Anode material and electrochemical device and electronic device including the same
An anode material includes a lithiated silicon oxide material and a M y SiO z layer. The lithiated silicon oxide material includes Li 2 SiO 3 , Li 2 Si 2 O 5 or a combination thereof, and the M y SiO z layer coats the lithiated silicon oxide material; M includes Mg, Al, Zn, Ca, Ba, B or any combination thereof; and 0<y<3, and 0.5<z<6. The anode material has high first discharge coulombic efficiency, high gram capacity, and good cycle performance.
1. An anode material, comprising: a lithiated silicon oxide material and a M y SiO z layer,
wherein the lithiated silicon oxide material includes Li 2 SiO 3 , Li 2 Si 2 O 5 or a combination thereof, and the M y SiO z layer is coated on the lithiated silicon oxide material;
M comprises B; and
0<y<3, and 0.5<z<6;
wherein a weight percentage of the M element is 10 wt % to 30 wt %, based on a total weight of the anode material.
2. The anode material according to claim 1 , wherein the M y SiO z layer further comprises Mg 2 SiO 4 , Al 2 SiO 5 , Zn 2 SiO 4 , CaSiO 3 , BaSiO 3 , or any combination thereof.
3. The anode material according to claim 1 , wherein a thickness of the M y SiO z layer is 0.2 μm to 3 μm.
4. The anode material according to claim 1 , further comprising a carbon layer coating on at least a portion of the M y SiO z layer.
5. The anode material according to claim 4 , wherein a thickness of the carbon layer is 1 nm to 500 nm.
6. The anode material according to claim 1 , wherein a weight percentage of the Li element is 2 wt % to 20 wt %, based on a total weight of the anode material.
7. The anode material according to claim 1 , wherein a ratio of a weight percentage of the Li element to that of the Si element is 3 to 30.
8. The anode material according to claim 1 , wherein a ratio of a weight percentage of the M element to that of the Si element is 5-60.
9. The anode material according to claim 1 , wherein the anode material includes nanometer Si grains.
10. A method for preparing an anode material, comprising:
(1) mixing a M source with a silicon oxide SiO x to form a mixed material;
carrying out a high-temperature treatment on the mixed material at 800-1300° C. for 1-5 h;
grinding the material subjected to the high-temperature treatment to obtain a grinded material; and
(2) mixing the grinded material with a Li source;
carrying out high-temperature treatment at 500-800° C. for 1-5 h;
wherein 0.5<x<2; and
M comprises B.
11. An anode comprising an anode material, wherein the anode material comprises a lithiated silicon oxide material and a M y SiO z layer, wherein
the lithiated silicon oxide material includes Li 2 SiO 3 , Li 2 Si 2 O 5 or a combination thereof, and the M y SiO z layer is coated on the lithiated silicon oxide material;
M comprises B; and 0<y<3, and 0.5<z<6;
wherein a weight percentage of the M element is 10 wt % to 30 wt %, based on a total weight of the anode material.
12. The anode according to claim 11 , wherein the M y SiO z layer further comprises Mg 2 SiO 4 , Al 2 SiO 5 , Zn 2 SiO 4 , CaSiO 3 , BaSiO 3 , or any combination thereof.
13. The anode according to claim 11 , wherein a thickness of the M y SiO z layer is 0.2 μm to 3 μm.
14. The anode according to claim 11 , further comprising a carbon layer coating on at least a portion of the M y SiO z layer.
15. The anode according to claim 14 , wherein a thickness of the carbon layer is 1 nm to 500 nm.
16. The anode according to claim 11 , wherein a weight percentage of the Li element is 2 wt % to 20 wt %, based on a total weight of the anode material.
17. The anode according to claim 11 , wherein a ratio of a weight percentage of the Li element to that of the Si element is 3 to 30.
18. The anode according to claim 11 , wherein a ratio of a weight percentage of the M element to that of the Si element is 5-60.