Negative electrode active material, negative electrode having the same and lithium secondary battery
A lithium secondary battery including a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material, a separator separating the positive electrode from the negative electrode and an electrolyte. The negative electrode active material includes a graphite core particle, a carbon layer coating the graphite core particle, and metal particles dispersed in the carbon layer.
1. A negative electrode active material, comprising:
a graphite core particle;
a carbon layer coating the graphite core particle; and
metal particles dispersed in the carbon layer;
wherein the graphite core particle, the carbon layer, and the metal particles form a metal-graphite composite having a porosity of from 0.03 to 0.08 cc/g;
wherein the graphite core particle has a porosity of from 0 to 0.025 cc/g; and
wherein the carbon layer is coated to an average thickness of from 1 to 4 μm.
2. The negative electrode active material according to claim 1 , wherein the graphite core particle is formed of one selected from the group consisting of artificial graphite, natural graphite, graphitized carbon fiber, graphitized mesocarbon microbeads, amorphous carbon, and a combination thereof.
3. The negative electrode active material according to claim 1 , wherein the metal particles are formed of one selected from the group consisting of Cr, Sn, Si, Al, Mn, Ni, Zn, Co, In, Cd, Bi, Pb, V, and a combination thereof.
4. A negative electrode, comprising:
a negative electrode collector; and
a negative electrode active material coated on the negative electrode collector, the negative electrode active material comprising,
a graphite core particle, a carbon layer coating the graphite core particle, and metal particles dispersed in the carbon layer;
wherein the graphite core particle, the carbon layer, and the metal particles form a metal-graphite composite having a porosity of from 0.03 to 0.08 cc/g;
wherein the graphite core particle has a porosity of from 0 to 0.025 cc/g; and
wherein the carbon layer is coated to an average thickness of from 1 to 4 μm.
5. A lithium secondary battery, comprising: a positive electrode comprising a positive electrode active material;
a negative electrode comprising a negative electrode active material, the negative
electrode active material comprising, a graphite core particle, a carbon layer coating the graphite core particle, and metal particles dispersed in the carbon layer; a separator to separate the positive electrode and the negative electrode; and
an electrolyte to immerse the positive and negative electrode;
wherein the graphite core particle, the carbon layer, and the metal particles form a metal-graphite composite having a porosity of from 0.03 to 0.08 cc/g;
wherein the graphite core particle has a porosity of from 0 to 0.025 cc/g; and
wherein the carbon layer is coated to an average thickness of from 1 to 4 μm.