Negative Electrode Active Material for Secondary Battery and Secondary Battery Including the Same
Provided is a negative electrode active material for a secondary battery including a carbon-based active material. The negative electrode active material satisfies the following Relational Expression 1, [Relational Expression 1] 0.1≤(D p −D T )/sphericity≤0.28 where D p is a pellet density (g/cm 3 ) of the carbon-based active material, D T is a tap density (g/cm 3 ) of the carbon-based active material, and the sphericity is a sphericity of a particle of the carbon-based active material.
1 . A negative electrode active material for a secondary battery, comprising a carbon-based active material,
wherein the negative electrode active material satisfies the following Relational Expression 1,
0.1≤( D p −D T )/sphericity≤0.28 [Relational Expression 1]
wherein D p is a pellet density (g/cm 3 ) of the carbon-based active material, D T is a tap density (g/cm 3 ) of the carbon-based active material, and the sphericity is a sphericity of a particle of the carbon-based active material.
2 . The negative electrode active material of claim 1 , wherein the negative electrode active material further satisfies the following Relational Expression 2,
D p −D T <0.3 [Relational Expression 2]
wherein D p is a pellet density (g/cm 3 ) of the carbon-based active material and D T is a tap density (g/cm 3 ) of the carbon-based active material.
3 . The negative electrode active material of claim 1 , wherein the sphericity of the particle of the carbon-based active material is 0.8 to 1.
4 . The negative electrode active material of claim 1 , wherein the pellet density (D p ) of the carbon-based active material is 1.0 to 1.5 g/cm 3 .
5 . The negative electrode active material of claim 1 , wherein the carbon-based active material is natural graphite or artificial graphite.
6 . The negative electrode active material of claim 1 , wherein a Raman R value of the negative electrode active material is 0.01 to 1.4, the Raman R value being represented by the following Equation 1,
Raman R=Id/Ig [Equation 1]
wherein the Raman R value is an index indicating a relative sphericity, and is calculated as a ratio of an intensity value of a peak in an absorption region of 1,350 to 1,380 cm −1 (Id) to an intensity value of a peak in an absorption region of 1,580 to 1,600 cm −1 (Ig) in Raman spectroscopy.
7 . The negative electrode active material of claim 1 , further comprising one or more selected from the group consisting of hard carbon and soft carbon.
8 . The negative electrode active material of claim 7 , wherein the amount of one or more selected from the group consisting of hard carbon and soft carbon comprised in the negative electrode active material is 5 to 15 wt % with respect to a total weight of the negative electrode active material.
9 . A negative electrode for a secondary battery, comprising the negative electrode active material of claim 1 .
10 . A secondary battery comprising:
the negative electrode of claim 9 ;
a positive electrode;
a separator interposed between the negative electrode and the positive electrode; and
an electrolyte.