HIGH NICKEL CATHODE MATERIAL HAVING LOW SOLUBLE BASE CONTENT

• US 20140054495A1
• Filed: 01/31/2012
• Published: 02/27/2014
• Est. Priority Date: 02/07/2011
• Status: Active Grant

• Current Assignee: Umicore S.A.
• Original Assignee: Ji Hye Kim
• Inventors: Paulsen, Jens, Kim, JiHye
• Granted Patent: US 9,698,418 B2
• Time in Patent Office: Days
• US Class Current: 252/182.1
• CPC Class Codes: C01D 15/02 Oxides; Hydroxides
• CPC Class Codes: C01G 53/50 of the type [MnO2]n- , e.g. Li(NixMn1-x)O2, Li(MyNixMn1-x-y)O2
• CPC Class Codes: C01P 2002/54 one element only
• CPC Class Codes: C01P 2006/12 Surface area
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/52 Removing gases inside the secondary cell, e.g. by absorption vent plugs or other mechanical arrangements for facilitating escape of gases H01M50/30
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The invention relates to cathode materials for Li-ion batteries in the quaternary phase diagram Li[Li_1/3Mn_2/3]O₂—LiMn_1/2Ni_1/2O₂—LiNiO₂—LiCoO₂, and having a high nickel content. Also a method to manufacture these materials is disclosed. The cathode material has a general formula Li_a((Ni_z(Ni_1/2Mn_1/2)_yCo_x)_1-kA_k)_2-aO₂, wherein x+y+z=1, 0.1≦x≦0.4, 0.36≦z≦0.50, A is a dopant, 0≦k≦0.1, and 0.95≦a≦1.05, and having a soluble base content (SBC) within 10% of the equilibrium soluble base content.

Claims

1-15. -15. (canceled)

16. A positive electrode material for lithium ion batteries, comprising a lithium transition metal oxide powder, wherein the lithium transition metal oxide powder has a general formula Li_a((Ni_z(Ni_1/2Mn_1/2)_yCo_x)_1-kA_k)_2-aO₂, wherein x+y+z=1, 0.1≦

x≦

0.4, 0.36≦

z≦

0.50, A is a dopant, 0≦

k≦

0.1, and 0.95≦

a≦

1.05, and has a soluble base content (SBC) that increases by less than 10% when the oxide powder is heated for 5 to 10 hours under air at a temperature ranging from 500°

C. to a temperature less than the temperature where the morphology of the powder changes by sintering.

17. The positive electrode material of claim 16, wherein 0.40≦

z≦

0.45.

19. The positive electrode material for lithium ion batteries, according to claim 16, having a BET surface area between 0.22 and 0.40 m²/g, and having a soluble base content (SBC) between 80 and 120 μ

mol/g.

20. The positive electrode material of claim 16, wherein the soluble base content (SBC) is the sum of the soluble base contents of Li₂CO₃ type base (SBC-Li₂CO₃) and LiOH type base (SBC-LiOH), both expressed in wt %, and wherein (SBC-Li₂CO₃)≧

0.085 wt %.

21. The positive electrode material of claim 20, wherein (SBC-Li₂CO₃)/(SBC-LiOH)>

0.2.

22. The positive electrode material of claim 16, having a surface specific SBC of 80-125 μ

mol/m², wherein the surface specific SBC is the ratio between SBC and BET surface area, wherein the BET surface area is measured after washing and drying.

23. The positive electrode material of claim 16, wherein A is one or more dopants selected from the group consisting of Al, Ti and Mg, and 0<

k≦

0.1.

24. The positive electrode material of claim 16, wherein A is one or more dopants selected from the group consisting of B, Ca, Mn, Cr, V, Fe, Zr, S, F, P and Bi, and 0<

k≦

0.01.

25. A method for preparing the positive electrode material LiMO₂ of claim 16, comprising the steps of:

providing a transition metal precursor MOOH prepared from the co-precipitation of transition metal sulphates with a base;

mixing the transition metal precursor with Li₂CO₃ to form a mixture, and

sintering the mixture under a forced flow of air of at least 2 m³/kg mixture, at a temperature T between 800° and

1000°

C., for a time t between 12 and 40 hrs, until no CO₂ is produced from the reaction MOOH+½

Li₂CO₃=>

LiMO₂+½

CO₂+½

H₂O.

26. A method for preparing the positive electrode material LiMO₂ of claim 16, comprising the steps of:

providing a transition metal precursor MOOH prepared from the co-precipitation of transition metal sulphates with a base;

mixing the transition metal precursor with Li₂CO₃ to form a mixture, and

sintering the mixture following the reaction MOOH+½

Li₂CO₃=>

LiMO₂+½

CO₂+½

H₂O under a forced flow of air of at least 2 m³/kg mixture, at a temperature T selected between 800° and

1000°

C., for a time t between 12 and 40 hrs, whereby at the completion of the time t no more CO₂ is produced.

27. The method according to claim 25, wherein the sintering step is performed at a temperature between 850 to 960°

C.

28. The method according to claim 25, wherein the transition metal precursor is obtained by co-precipitating transition metal sulphates and NaOH.

29. The method according to claim 25, wherein the transition metal precursor is a mixed hydroxide or oxyhydroxide containing between 0.1 and 1.0 wt % CO₃²⁻

.

30. The method according to claim 25, wherein the sintering step is preceded by heating the mixture for at least 5 hrs at a temperature from 650°

C. to 800°

C., under a forced flow of air of at least 2 m³/kg mixture.

18. A positive electrode material for lithium ion batteries, comprising a lithium transition metal oxide powder, wherein the lithium transition metal oxide powder has a general formula Li_a((Ni_z(Ni_1/2Mn_1/2)_yCo_x)_1-kA_k)_2-aO₂, wherein x+y+z=1, 0.1≦

x≦

0.4, 0.36≦

z≦

0.50, A is a dopant, 0≦

k≦

0.1, and 0.95≦

a≦

1.05, and has a soluble base content (SBC) that increases by less than 10% when the oxide powder is heated for 10 hours under air at a temperature of 790°

C.