Battery, negative electrode active material, and electric tool
View Patent ↗A battery is provided including a positive electrode; a negative electrode including a first negative electrode active material; and an electrolytic solution, wherein the first negative electrode active material includes a core portion having a core portion surface, wherein the core portion has a median diameter of 0.3 μm to 20 μm, and a covering portion that covers at least part of the core portion surface, wherein the covering portion comprises at least Si, O and at least of one element M1 selected from Li, carbon (C), Mg, Al, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Ge, Zr, Mo, Ag, Sn, Ba, W, Ta, Na, and K.
1. A battery comprising:
a positive electrode;
a negative electrode including a first negative electrode active material; and
an electrolytic solution,
wherein the first negative electrode active material includes:
a core portion having a core portion surface, wherein the core portion has a median diameter of 0.3 μm to 20 μm, and
a covering portion that covers at least part of the core portion surface,
wherein the covering portion comprises at least Si, O and at least of one element M1 selected from Li, carbon (C), Mg, Al, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Ge, Zr, Mo, Ag, Sn, Ba, W, Ta, Na, and K.
2. The battery according to claim 1 , wherein the covering portion covers from 30% to 100% of the core portion surface.
3. The battery according to claim 1 , wherein the covering portion has a thickness of 1 nm to 10,000 nm.
4. The battery according to claim 1 , wherein the covering portion has a multilayer structure.
5. The battery according to claim 1 ,
wherein the first negative electrode active material includes a conductive portion that covers at least part of a surface of the covering portion, and wherein the conductive portion has a lower electrical resistance than any one of the core portion and the covering portion.
6. The battery according to claim 1 , wherein the negative electrode further includes a second negative electrode active material.
7. The battery according to claim 6 , wherein the second negative electrode active material includes a carbon material.
8. The battery according to claim 7 , wherein the core portion includes carbon.
9. The battery according to claim 8 , wherein the element M1 is carbon.
10. The battery according to claim 9 , wherein the positive electrode includes
lithium cobalt oxide.
11. The battery according to claim 1 , wherein an atomic ratio y (O/Si) of O to Si in the covering portion is 0.5≦y≦1.8.
12. The battery according to claim 1 , wherein the core portion includes at least one of Si and Sn.
13. The battery according to claim 7 , wherein the electrolytic solution includes a nonaqueous solvent comprising at least one selected from the group consisting of a halogenated chain carbonate and a halogenated cyclic carbonate.
14. The battery according to claim 13 , wherein the halogenated cyclic carbonate comprises at least one selected from the group consisting of 4-fluoro-1,3-dioxolan-2-one and 4,5-difluoro-1,3-dioxolan-2-one.
15. The battery according to claim 13 , wherein an amount of the at least one selected from the group consisting of the halogenated chain carbonate and the halogenated cyclic carbonate ranges from 0.01% by weight to 50% by weight of the nonaqueous solvent.
16. The battery according to claim 7 , wherein the negative electrode includes a negative electrode collector comprising at least one selected from the group consisting of carbon and sulfur.
17. The battery according to claim 16 , wherein a content of the at least one selected from the group consisting of carbon and sulfur in the negative electrode collector is 100 ppm or less.
18. An electric tool comprising:
a battery including a positive electrode, a negative electrode including a negative electrode active material, and an electrolytic solution; and
a moving part configured to be powered by the battery,
wherein the negative electrode active material includes:
a core portion having a core portion surface, wherein the core portion has a median diameter of 0.3 μm to 20 μm, and
a covering portion that covers at least part of the core portion surface,
wherein the covering portion comprises at least Si, O and at least of one element M1 selected from Li, carbon (C), Mg, Al, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Ge, Zr, Mo, Ag, Sn, Ba, W, Ta, Na, and K.
19. A negative electrode active material comprising:
a core portion having a core portion surface, wherein the core portion has a median diameter of 0.3 μm to 20 μm, and
a covering portion that covers at least a part of the core portion surface,
wherein the covering portion comprises at least Si and O and at least of one element M1 selected from Li, carbon (C), Mg, Al, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Ge, Zr, Mo, Ag, Sn, Ba, W, Ta, Na, and K.
20. The negative electrode active material according to claim 19 , wherein the covering portion covers from 30% to 100% of the core portion surface.
21. The negative electrode active material according to claim 19 , wherein the covering portion has a thickness of 1 nm to 10,000 nm.
22. The negative electrode active material according to claim 19 , wherein the covering portion has a multilayer structure.
23. The negative electrode active material according to claim 19 , further comprising a conductive portion that covers at least part of a surface of the covering portion, wherein the conductive portion has a lower electrical resistance than any one of the core portion and the covering portion.
24. The negative electrode active material according to claim 19 , wherein the element M1 is carbon.
25. The negative electrode active material according to claim 19 , wherein an atomic ratio y (O/Si) of O to Si is 0.5≦y≦1.8.
26. The negative electrode active material according to claim 19 , wherein the core portion includes at least one of Si and Sn.
27. The negative electrode active material according to claim 19 , wherein the core portion includes carbon.