Positive active material composition for rechargeable battery, electrode including the same, and rechargeable battery including the same
A positive active material composition for a rechargeable battery, a positive electrode including the same, and a rechargeable battery including the same, the positive active material composition including a positive active material and a surface-modified metal oxide.
1. A positive active material composition for a rechargeable battery, comprising:
a positive active material; and
a surface-modified metal oxide, the surface-modified metal oxide including an MR x functional group at its surface, wherein M is Si, Ti, Zr, or Mg, R is a C 1 -C 3 alkyl, and x is 1 to 4.
2. The positive active material composition as claimed in claim 1 , wherein the surface-modified metal oxide includes, at a center region thereof, at least one of SiO 2 , ZrO 2 , TiO 2 , and MgO.
3. The positive active material composition as claimed in claim 2 , wherein the surface-modified metal oxide includes Si(CH 3 ) 3 at its surface and SiO 2 at the center region thereof.
4. The positive active material composition as claimed in claim 1 , wherein the surface-modified metal oxide is included in an amount of about 1 to about 10 wt % based on the weight of the positive active material.
5. The positive active material composition as claimed in claim 4 , wherein the surface-modified metal oxide is included in an amount of about 1 to about 5 wt % based on the weight of the positive active material.
6. The positive active material composition as claimed in claim 1 , wherein the positive active material includes at least one compound represented by the following Formulae 1 to 25:
Li a A 1−b X b D 2 (1),
wherein 0.95≦a≦1.1 and 0≦b≦0.5
Li a E 1−b X b O 2−c M c (2),
wherein 0.95≦a≦1.1, 0≦b≦0.5, and 0≦c≦0.05
LiE 2−b X b O 4−c M c (3),
wherein 0≦b≦0.5 and 0≦c≦0.05
Li a Ni 1−b−c Co b X c D α (4),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α≦2
Li a Ni 1−b−c Co b X c O 2−α M α (5),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Co b X c O 2−α M 2 (6),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Mn b X c D α (7),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α≦2
Li a Ni 1−b−c Mn b X c O 2−α M α (8),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Mn b X c O 2−α M 2 (9),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni b E c G d O 2 (10),
wherein 0.90≦a≦1.1, 0≦b≦0.9, 0≦c≦0.5, and 0.001≦d≦0.1
Li a Ni b Co c Mn d G e O 2 (11),
wherein 0.90≦a≦1.1, 0≦b≦0.9, 0≦c≦0.5, 0≦d≦0.5, and 0.001≦e≦0.1
Li a NiG b O 2 (12),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a CoG b O 2 (13),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a MnG b O 2 (14),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a Mn 2 G b O 4 (15),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
QO 2 (16),
QS 2 (17),
LiQS 2 (18),
V 2 O 5 (19),
LiV 2 O 5 (20),
LiZO 2 (21),
LiNiVO 4 (22),
Li (3−f) J 2 (PO 4 ) 3 (23),
wherein 0≦f≦2
Li (3−f) Fe 2 (PO 4 ) 3 (24),
wherein 0≦f≦2
LiFePO 4 (25)
wherein, in Formulae 1 to 25:
A includes at least one of Ni, Co, and Mn,
X includes at least one of a rare earth element, Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, and V,
D includes at least one of O, F, S, and P,
E includes at least one of Co and Mn,
M includes at least one of F, S, and P,
G includes at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, and V,
Q includes at least one of Ti, Mo, and Mn,
Z includes at least one of Cr, V, Fe, Sc, and Y, and
J includes at least one of V, Cr, Mn, Co, Ni, and Cu.
7. A positive electrode for a rechargeable battery, comprising:
a current collector; and
a positive active material layer including a positive active material and a surface-modified metal oxide, the surface-modified metal oxide including an MR x functional group at its surface, wherein M is Si, Ti, Zr, or Mg, R is a C 1 -C 3 alkyl, and x is 1 to 4.
8. The positive electrode as claimed in claim 7 , wherein the surface-modified metal oxide includes, at a center region thereof, at least one of SiO 2 , ZrO 2 , TiO 2 , and MgO.
9. The positive electrode as claimed in claim 8 , wherein the surface-modified metal oxide includes Si(CH 3 ) 3 at its surface and SiO 2 at the center region thereof.
10. The positive electrode as claimed in claim 7 , wherein the surface-modified metal oxide is included in the positive active material layer in an amount of about 1 to about 10 wt % based on the weight of the positive active material.
11. The positive electrode as claimed in claim 10 , wherein the surface-modified metal oxide is included in the positive active material layer in an amount of about 1 to about 5 wt % based on the weight of the positive active material.
12. The positive electrode as claimed in claim 7 , wherein the positive active material includes at least one compound represented by the following Formulae 1 to 25:
Li a A 1−b X b D 2 (1),
wherein 0.95≦a≦1.1 and 0≦b≦0.5
Li a E 1−b X b O 2−c M c (2),
wherein 0.95≦a≦1.1, 0≦b≦0.5, and 0≦c≦0.05
LiE 2−b X b O 4−c M c (3),
wherein 0≦b≦0.5 and 0≦c≦0.05
Li a Ni 1−b−c Co b X c D α (4),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α≦2
Li a Ni 1−b−c Co b X c O 2−α M α (5),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Co b X c O 2−α M 2 (6),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Mn b X c D α (7),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α≦2
Li a Ni 1−b−c Mn b X c O 2−α M α (8),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni 1−b−c Mn b X c O 2−α M 2 (9),
wherein 0.95≦a≦1.1, 0≦b≦0.5, 0≦c≦0.05, and 0<α<2
Li a Ni b E c G d O 2 (10),
wherein 0.90≦a≦1.1, 0≦b≦0.9, 0≦c≦0.5, and 0.001≦d≦0.1
Li a Ni b Co c Mn d G e O 2 (11),
wherein 0.90≦a≦1.1, 0≦b≦0.9, 0≦c≦0.5, 0≦d≦0.5, and 0.001≦e≦0.1
Li a NiG b O 2 (12),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a CoG b O 2 (13),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a MnG b O 2 (14),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
Li a Mn 2 G b O 4 (15),
wherein 0.90≦a≦1.1 and 0.001≦b≦0.1
QO 2 (16),
QS 2 (17),
LiQS 2 (18),
V 2 O 5 (19),
LiV 2 O 5 (20),
LiZO 2 (21),
LiNiVO 4 (22),
Li (3−f) J 2 (PO 4 ) 3 (23),
wherein 0≦f≦2
Li (3−f) Fe 2 (PO 4 ) 3 (24),
wherein 0≦f≦2
LiFePO 4 (25)
wherein, in Formulae 1 to 25:
A includes at least one of Ni, Co, and Mn,
X includes at least one of a rare earth element, Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, and V,
D includes at least one of O, F, S, and P,
E includes at least one of Co and Mn,
M includes at least one of F, S, and P,
G includes at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, and V,
Q includes at least one of Ti, Mo, and Mn,
Z includes at least one of Cr, V, Fe, Sc, and Y, and
J includes at least one of V, Cr, Mn, Co, Ni, and Cu.
13. A rechargeable battery, comprising:
a positive electrode including a current collector and a positive active material layer including a positive active material and a surface-modified metal oxide, the surface-modified metal oxide including an MR x functional group at its surface, wherein M is Si, Ti, Zr, or Mg, R is a C 1 -C 3 alkyl, and x is 1 to 4;
a negative electrode including a negative active material; and
a non-aqueous electrolyte.
14. The rechargeable battery as claimed in claim 13 , wherein the surface-modified metal oxide includes, at a center region thereof, at least one of SiO 2 , ZrO 2 , TiO 2 , and MgO.
15. The rechargeable battery as claimed in claim 14 , wherein the surface-modified metal oxide includes Si(CH 3 ) 3 at its surface and SiO 2 at the center region thereof.
16. The rechargeable battery as claimed in claim 13 , wherein the surface-modified metal oxide is included in the positive active material layer in an amount of about 1 to about 10 wt % based on the weight of the positive active material.
17. The rechargeable battery as claimed in claim 16 , wherein the surface-modified metal oxide is included in the positive active material layer in an amount of about 1 to about 5 wt % based on the weight of the positive active material.