Method of producing lithium ion cathode materials

Abstract

A method of producing Li y [Ni x Co 1−2x Mn x ]O 2 wherein 0.025≦x≦0.5 and 0.9≦y≦1.3. The method includes mixing [Ni x Co 1−2x Mn x ]OH 2 with LiOH or Li 2 CO 3 and one or both of alkali metal fluorides and boron compounds, preferably one or both of LiF and B 2 O 3 . The mixture is heated sufficiently to obtain a composition of Li y [Ni x Co 1−2x Mn x ]O 2 sufficiently dense for use in a lithium-ion battery cathode. Compositions so densified exhibit a minimum reversible volumetric energy characterized by the formula [1833−333 x ] measured in Wh/L.

1 . A lithium transition metal oxide for use in a lithium-ion battery having the general formula Li y [Ni x Co 1−2x Mn x ]O 2 , wherein 0.1≦x≦0.375, and 0.9≦y≦1.3, produced by a method comprising:
 grinding a dry precipitate of [Ni x Co 1−2x Mn x ]OH 2  with a stoichiometric amount of LiOH.H 2 O or Li 2 CO 3  and one or both of alkali metal fluorides and boron compounds as sintering agents to form a resulting mixture; and   heating the resulting mixture until a composition of Li y [Ni x Co 1−2x Mn x ]O 2  having a pellet density of from about 3.3 to about 3.5 g/cm 3  is obtained for use in a lithium-ion battery, to form a densified composition of Li y [Ni x Co 1−2x Mn x ]O 2      wherein the total amount of boron compound(s) is greater than 0.2% and up to about 10% of the total weight of the mixture, and wherein   the composition exhibits a reversible volumetric energy of at least [1833−333x] measured in Wh/L.   
     
     
         2 . The lithium transition metal oxide of  claim 1  exhibiting a pellet density of at least about 72% of theoretical density. 
     
     
         3 . The lithium transition metal oxide of  claim 1  exhibiting a pellet density of at least about 74% of theoretical density. 
     
     
         4 . The lithium transition metal oxide of  claim 2  that is formed into a lithium ion battery electrode having a reversible volumetric energy in the range of 1500 to 2200 Wh/L. 
     
     
         5 . The lithium transition metal oxide of  claim 3  that is formed into a lithium ion battery electrode having a reversible volumetric energy in the range of 1500 to 2200 Wh/L. 
     
     
         6 . A lithium transition metal oxide for use in a lithium-ion battery having the general formula of Li y [Ni x Co 1−2x Mn x ]O 2  wherein 0.025≦x≦0.35, and 0.9≦y≦1.3, and exhibiting a minimum reversible volumetric energy characterized by the formula [1833−333x] measured in Wh/L. 
     
     
         7 . The lithium transition metal oxide of  claim 6  exhibiting a pellet density of at least 72% of theoretical density. 
     
     
         8 . The lithium transition metal oxide of  claim 6  exhibiting a pellet density of at least 74% of theoretical density. 
     
     
         9 . The lithium transition metal oxide of  claim 7  that is formed into a lithium ion battery electrode having a reversible volumetric energy in the range of 1500 to 2200 Wh/L. 
     
     
         10 . The lithium transition metal oxide of  claim 8  that is formed into a lithium ion battery electrode having a reversible volumetric energy in the range of 1500 to 2200 Wh/L.