Silicon-containing negative active material, method of preparing the same, negative electrode including the same, and lithium secondary battery including negative electrode
A silicon-containing negative active material may include a silicon particle and a coating layer surrounding the silicon particle, and the coating layer may include carbon and a metallic particle.
1. A silicon-containing negative active material comprising:
a silicon particle; and
a coating layer which comprises carbon and a metallic particle, and surrounds the silicon particle,
wherein the coating layer comprises a first carbon film comprising the carbon and surrounding the metallic particle, and
wherein the first carbon film comprises about two layers to about fifteen layers of first carbon layers stacked one over another.
2. The silicon-containing negative active material of claim 1 , wherein each of the first carbon layers has a concentric sphere shape.
3. The silicon-containing negative active material of claim 1 , wherein the coating layer further comprises a second carbon film not surrounding the metallic particle.
4. The silicon-containing negative active material of claim 3 , wherein the second carbon film comprises about two layers to about fifteen layers of second carbon layers stacked one over another.
5. The silicon-containing negative active material of claim 4 , wherein each of the second carbon layers has a concentric sphere shape.
6. The silicon-containing negative active material of claim 1 , wherein the metallic particle comprises one of cobalt (Co), zinc (Zn), iron (Fe), nickel (Ni), tin (Sn), and any combination thereof.
7. The silicon-containing negative active material of claim 1 , wherein the metallic particle has an average diameter in a range of about 5 nanometers to about 30 nanometers.
8. The silicon-containing negative active material of claim 1 , wherein the silicon particle has an average diameter in a range of about 50 nanometers to about 500 nanometers.
9. The silicon-containing negative active material of claim 1 , wherein the coating layer has a thickness in a range of about 0.3 nanometers to about 30 nanometers.
10. The silicon-containing negative active material of claim 1 , wherein the coating layer comprises carbide of a metal-organic framework.
11. A negative electrode comprising a current collector on which a silicon-containing negative active material is disposed, the silicon-containing negative active material comprising:
a silicon particle; and
a coating layer which comprises carbon and a metallic particle, and surrounds the silicon particle,
wherein the coating layer comprises a first carbon film comprising the carbon and surrounding the metallic particle, and
wherein the first carbon film comprises about two layers to about fifteen layers of first carbon layers stacked one over another.
12. A lithium secondary battery comprising:
a positive electrode;
an electrolyte; and
a negative electrode comprising a current collector on which on which a silicon-containing negative active material is disposed, the silicon-containing negative active material comprising:
a silicon particle; and
a coating layer which comprises carbon and a metallic particle, and surrounds the silicon particle,
wherein the coating layer comprises a first carbon film comprising the carbon and surrounding the metallic particle, and
wherein the first carbon film comprises about two layers to about fifteen layers of first carbon layers stacked one over another.