Anode material for secondary battery and secondary batteries using the same

Abstract

Disclosed are an anode material for a secondary battery and a secondary battery using the same. The present invention provides the anode material for a secondary battery, produced by coating a high-crystallinity core carbonaceous material with a coating carbonaceous material and calcining the high-crystallinity core carbonaceous material, wherein the anode material for a secondary battery has a delamination area of 0.1×10−5 to 1.0×10−4 or a volume fraction of water uptake of 0.01 or less. The secondary battery according to the present invention may be useful to improve a charging/discharging capacity and a charging/discharging efficiency of the battery and ensure a stability of the battery since the battery has an improved protection against a degradation reaction of an electrolyte if the battery is produced using the anode material for a secondary battery.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and aspects of the present invention will become apparent from the following description of embodiments with reference to the accompanying drawings. However, it should be understood that the description proposed herein is just a preferable example for the purpose of illustrations only, not intended to limit the scope of the invention. In the drawings:

FIG. 1 is a diagram showing a section of a carbon electrode and an equivalent circuit for the carbon electrode together.

Claims

1. An anode material for a secondary battery, produced by coating a high-crystallinity core carbonaceous material with a coating carbonaceous material and calcining the high-crystallinity core carbonaceous material, wherein the anode material for a secondary battery has a delamination area of 0.1×10−5 to 1.0×10−4.

2. The anode material for a secondary battery according to claim 1, wherein the coating carbonaceous material has a relatively lower Raman intensity ratio than the core carbonaceous material.

3. The anode material for a secondary battery according to claim 1, wherein the anode material for a secondary battery has a ratio (I1360/I1580) of 0.01 to 0.45, the ratio (I1360/I1580) being a ratio of a peak intensity (I1360) at 1,360 cm−1 to a peak intensity (I1580) at 1,580 cm−1 observed by a Raman spectroscopy analysis using an argon (Ar) laser having a wavelength of 514.5 nm.

4. The anode material for a secondary battery according to claim 1, wherein the anode material for a secondary battery has a tap density of 0.7 g/cm3 or more.

5. The anode material for a secondary battery according to claim 1, wherein the anode material for a secondary battery has a BET specific surface area of 4 m2/g or less.

6. The anode material for a secondary battery according to claim 1, wherein the high-crystallinity core carbonaceous material is natural graphite.

7. A secondary battery produced using, as a battery anode, the anode material for a secondary battery as defined in any of claims 1 to 6.

8. The secondary battery according to claim 7, wherein the secondary battery has a discharging capacity of 340 mAh/g or more and a charging/discharging efficiency of 90% or more.

9. An anode material for a secondary battery, produced by coating a high-crystallinity core carbonaceous material with a coating carbonaceous material and calcining the high-crystallinity core carbonaceous material, wherein the anode material for a secondary battery has a volume fraction of water uptake of 0.01 or less.

10. The anode material for a secondary battery according to claim 9, wherein the coating carbonaceous material has a relatively lower Raman intensity ratio than the core carbonaceous material.

11. The anode material for a secondary battery according to claim 9, wherein the anode material for a secondary battery has a ratio (I1360/I1580) of 0.01 to 0.45, the ratio (I1360/I1580) being a ratio of a peak intensity (I1360) at 1,360 cm−1 to a peak intensity (I1580) at 1,580 cm−1 observed by a Raman spectroscopy analysis using an argon (Ar) laser having a wavelength of 514.5 nm.

12. The anode material for a secondary battery according to claim 9, wherein the anode material for a secondary battery has a tap density of 0.7 g/cm3 or more.

13. The anode material for a secondary battery according to claim 9, wherein the anode material for a secondary battery has a BET specific surface area of 4 m2/g or less.

14. The anode material for a secondary battery according to claim 9, wherein the high-crystallinity core carbonaceous material is natural graphite.

15. A secondary battery produced using, as a battery anode, the anode material for a secondary battery as defined in any of claims 9 to 14.

16. The secondary battery according to claim 15, wherein the secondary battery has a discharging capacity of 340 mAh/g or more and a charging/discharging efficiency of 90% or more.