ANODE ACTIVE MATERIAL AND THE SECONDARY BATTERY COMPRISING THE SAME
Disclosed is an anode active material comprising a lithium metal oxide represented by the following Formula 1, wherein the anode active material is surface-coated with a silane compound and a silicon content of the silane compound is 0.01 to 5% by weight, based on the total amount of the anode active material: Li a M′ b O 4−c A c (1) wherein M′ is at least one element selected from the group consisting of Ti, Sn, Cu, Pb, Sb, Zn, Fe, In, Al and Zr; a and b are determined according to an oxidation number of M′ within ranges of 0.1≦a≦4 and 0.2≦b≦4; c is determined according to an oxidation number within a range of 0≦c<0.2; and A is at least one monovalent or bivalent anion. Disclosed is also a secondary battery comprising the same.
1 . An anode active material comprising a lithium metal oxide represented by the following Formula 1,
wherein the anode active material is surface-coated with a silane compound and a silicon content of the silane compound is 0.01 to 5% by weight, based on the total amount of the anode active material:
Li a M′ b O 4−c A c (1)
wherein M′ is at least one element selected from the group consisting of Ti, Sn, Cu, Pb, Sb, Zn, Fe, In, Al and Zr;
a and b are determined according to an oxidation number of M′ within ranges of 0.1≦a≦4 and 0.2≦b≦4;
c is determined according to an oxidation number within a range of 0≦c<0.2; and
A is at least one monovalent or bivalent anion.
2 . The anode active material according to claim 1 , wherein the silane compound is represented by the following Formula a:
R 1 —Si(R 2 )(R 3 )—R 4 (a)
wherein one or more of R 1 , R 2 , R 3 and R 4 are each independently hydrogen, a halogen, alkylamino, dialkylamino, alkyl alcohol, C 1 -C 20 alkyl, C 1 -C 20 alkenyl, C 1 -C 20 alkynyl, C 1 -C 20 alkoxy, C 1 -C 20 alkoxy carbonyl, C 1 -C 20 acyl, C 3 -C 20 cycloalkyl, C 6 -C 18 aryl, C 2 -C 18 allyl, nitrile, silazane or phosphate.
3 . The anode active material according to claim 2 , wherein in the silane compound of Formula a, one or more of R 1 to R 3 are a halogen, silazane or C 1 -C 20 alkoxy, C 6 -C 18 aryl, or C 2 -C 18 allyl, and R 4 is C 1 -C 20 alkyl, nitrile, fluorine or phosphate.
4 . The anode active material according to claim 2 , wherein, in the silane compound of Formula a, R 1 and R 2 are a halogen, silazane or C 1 -C 20 alkoxy, C 6 -C 18 aryl or C 2 -C 18 allyl, and R 3 and R 4 are C 1 -C 20 alkyl, nitrile, fluorine or phosphate.
5 . The anode active material according to claim 2 , wherein, in the silane compound of Formula a, one or more of R 1 to R 3 are C 1 -C 20 alkyl, C 1 -C 20 alkoxy or C 2 -C 18 allyl, and R 4 is silazane.
6 . The anode active material according to claim 5 , wherein the silane compound of Formula a is hexamethyldisilazane.
7 . The anode active material according to claim 1 , wherein a silicon content of the silane compound is 0.01 to 3% by weight, with respect to the total weight of the cathode active material.
8 . The anode active material according to claim 1 , wherein the lithium metal oxide is represented by the following Formula 2:
Li a Ti b O 4 (2)
wherein 0.5≦a≦3 and 1≦b≦2.5.
9 . The anode active material according to claim 8 , wherein the lithium metal oxide is Li 1.33 Ti 1.67 O 4 or LiTi 2 O 4 .
10 . A secondary battery comprising the anode active material according to claim 1 .
11 . The secondary battery according to claim 10 , wherein the secondary battery is a lithium secondary battery.
12 . A battery module comprising the secondary battery according to claim 10 as a unit battery.
13 . A battery pack comprising the battery module according to claim 12 .
14 . A device comprising the battery pack according to claim 13 .
15 . The device according to claim 14 , wherein the device is an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle or a power storage system.