Positive electrode material for lithium-ion battery
A composite lithiated nickel-based positive electrode material in which the water-containing excess lithium compounds LiOH and LiHCO 3 have a combined content of at least 10 times lower than the content of the water-free excess lithium compound Li 2 CO 3 . There is further provided a lithium-ion battery comprising the positive electrode material having the significantly reduced amount of LiOH and LiHCO 3 .
1 . A positive electrode material for a lithium-ion or lithium-ion polymer battery, having the formula
LiNi X Co Y M Z O 2 .(LiOH) k (Li 2 CO 3 ) m (LiHCO 3 ) n
wherein M is one or more transition metals different than Ni and Co, X+Y+Z=1, X≧Y, Z<0.5, 0.001<k+m+n<0.3, and k+n<0.1m.
2 . The positive electrode material of claim 1 wherein k+n<0.01m.
3 . The positive electrode material of claim 1 wherein k+n<0.001m.
4 . The positive electrode material of claim 1 wherein Y−0.
5 . The positive electrode material of claim 4 wherein k+n<0.01m.
6 . The positive electrode material of claim 4 wherein k+n<0.001m.
7 . The positive electrode material of claim 1 prepared by exposing the positive electrode material at a temperature of 0-650° C. to a CO 2 -containing gas having a partial pressure of CO 2 in the range of 0.0001-100 atm to convert LiOH to Li 2 CO 3 .
8 . The positive electrode material of claim 7 further prepared by heating the positive electrode material to a temperature of at least 250° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 .
9 . The positive electrode material of claim 1 prepared by heating the positive electrode material to a temperature of at least 250° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 .
10 . The positive electrode material of claim 1 prepared by heating the positive electrode material to a temperature of 250-500° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 and in the presence of a CO 2 -containing gas having a partial pressure of CO 2 in the range of 0.0001-100 atm to convert LiOH to Li 2 CO 3 .
11 . A lithium ion battery comprising a positive electrode material of the formula
LiNi X Co Y M Z O 2 .(LiOH) k (Li 2 CO 3 ) m (LiHCO 3 ) n
wherein M is one or more transition metals different than Ni and Co, X+Y+Z=1, X≧Y, Z<0.5, 0.001<k+m+n<0.3, and k+n<0.1m.
12 . The lithium ion battery of claim 11 wherein k+n<0.01m.
13 . The lithium ion battery of claim 11 wherein k+n<0.001m.
14 . The lithium ion battery of claim 11 wherein Y=0.
15 . The lithium ion battery of claim 14 wherein k+n<0.01m.
16 . The lithium ion battery of claim 14 wherein k+n<0.001m.
17 . The lithium ion battery of claim 11 wherein the positive electrode material is prepared by exposing the positive electrode material at a temperature of 0-650° C. to a CO 2 -containing gas having a partial pressure of CO 2 in the range of 0.0001-100 atm to convert LiOH to Li 2 CO 3 .
18 . The lithium ion battery of claim 17 wherein the positive electrode material is further prepared by heating the positive electrode material to a temperature of at least 250° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 .
19 . The lithium ion battery of claim 11 wherein the positive electrode material is prepared by heating the positive electrode material to a temperature of at least 250° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 .
20 . The lithium ion battery of claim 11 wherein the positive electrode material is prepared by heating the positive electrode material to a temperature of 250-500° C. in the presence of an oxygen-containing gas having a partial pressure of O 2 in the range of 0.01-99 atm to convert LiHCO 3 to Li 2 CO 3 and in the presence of a CO 2 -containing gas having a partial pressure of CO 2 in the range of 0.0001-100 atm to convert LiOH to Li 2 CO 3 .