Metal oxide coated positive electrode materials for lithium-based batteries

• US 8,535,832 B2
• Filed: 08/27/2010
• Issued: 09/17/2013
• Est. Priority Date: 08/27/2009
• Status: Active Grant

• Current Assignee: Ionblox Incorporated (Zenlabs Energy, Inc.)
• Original Assignee: Envia Systems, Inc.
• Inventors: Karthikeyan, Deepak Kumaar Kandasamy, Venkatachalam, Subramanian, Lopez, Herman A., Kumar, Sujeet
• Primary Examiner(s): WEINER, LAURA S
• Application Number:
  US12/870,096
• Publication Number:
  US 20110076556A1
• Time in Patent Office: 1,117 Days
• Field of Search: 429/231.1, 429/231.3, 252/182.1, 427/58, 427/126.1, 427/123
• US Class Current: 429/231.1
• CPC Class Codes: C01G 45/1257 containing lithium, e.g. Li2MnO3, Li2[MxMn1-xO3
• CPC Class Codes: C01G 51/50 of the type [MnO2]n- , e.g. Li(CoxMn1-x)O2, Li(MyCoxMn1-x-y)O2
• 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 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2002/88 by thermal analysis data, e.g. TGA, DTA, DSC
• CPC Class Codes: C01P 2004/32 Spheres
• CPC Class Codes: C01P 2004/84 one phase coated with the other
• CPC Class Codes: C01P 2006/11 Powder tap density
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• 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: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Positive electrode active materials are formed with various metal oxide coatings. Excellent results have been obtained with the coatings on lithium rich metal oxide active materials. Surprisingly improved results are obtained with metal oxide coatings with lower amounts of coating material. High specific capacity results are obtained even at higher discharge rates.

Claims

1. A lithium ion battery positive electrode material comprising a lithium metal oxide coated with a metal/metalloid oxide coating composition,

wherein the lithium metal oxide can be approximately represented by a formula Li_1+aNi_α

Mn_β

Co_γ

A_δ

O<sub>2−

z</sub>F_z, where a ranges from about 0.05 to about 0.3, a ranges from 0 to about 0.4, β

range from about 0.2 to about 0.65, γ

ranges from 0 to about 0.46, δ

ranges from about 0 to about 0.15, z ranges from 0 to about 0.2 with the proviso that both α and

γ

are not zero, and where A is Mg, Sr, Ba, Cd, Zn, Al, Ga, B, Zr, Ti, Ca, Ce, Y, Nb, Cr, Fe, V, or combinations thereof,

wherein the coating composition comprises less than 2 weight percent of the positive electrode material, and

wherein after the material is activated in the first cycle to a charge of 4.6V at a rate of C/10, the positive electrode material has a specific discharge capacity of at least about 260 mAh/g with a discharge rate of C/3 when discharged from 4.6V to 2.0 V at room temperature and a specific discharge capacity of at least about 230 mAh/g with a discharge rate of C/3 at the 50th charge/discharge cycle when discharged from 4.6V to 2.0 V at room temperature.

2. The positive electrode material of claim 1 wherein the metal/metalloid oxide coating composition comprises aluminum oxide (Al₂O₃), bismuth oxide (Bi₂O₃), boron oxide (B₂O₃), zirconium oxide (ZrO₂), magnesium oxide (MgO), chromium oxide (Cr₂O₃), magnesium aluminate (MgAl₂O₄), gallium oxide (Ga₂O₃), silicon oxide (SiO₂), tin oxide (SnO₂), calcium oxide (CaO₂), strontium oxide (SrO), barium oxide (BaO), titanium oxide (TiO₂), iron oxide (Fe₂O₃), molybdenum oxide (MoO₃ and MoO₂), cerium oxide (CeO₂), lanthanum oxide (La₂O₃), zinc oxide (ZnO), lithium aluminum oxide (LiAlO₂), or combinations thereof.

3. The positive electrode material of claim 1 wherein the coating composition comprises aluminum oxide.

4. The positive electrode material of claim 1 wherein the coating composition comprises from about 0.025 to about 1 weight percent of the positive electrode material.

5. The positive electrode material of claim 1 wherein the coating composition comprises from about 0.1 to about 0.75 weight percent of the positive electrode material.

6. The positive electrode material of claim 1 wherein the irreversible capacity loss is reduced by at least about 10% relative to the irreversible capacity loss of the uncoated lithium metal oxide.

7. The positive electrode material of claim 1 wherein z=0 and the lithium metal oxide is approximately represented by the formula x Li₂MnO₃.(1−

x)LiNi_u+Δ

Mn<sub>u−

Δ</sub>

Co_wA_yO₂. wherein 2u+w+y≈

1, −

0.3≦

Δ

≦

0.3, 0≦

w≦

1, 0≦

u≦

0.5, and 0≦

y≦

0.1, with the proviso that both (u+Δ

) and w are not zero.

8. A lithium ion battery comprising

a positive electrode comprising the positive electrode material of claim 1,

a negative electrode comprising a lithium incorporation composition,

a separator between the positive electrode and the negative electrode, and

an electrolyte comprising lithium ions,

wherein the positive electrode material has a specific discharge capacity of at least about 230 mAh/g with a discharge rate of C/3 at the 50th charge/discharge cycle when discharged from 4.6V to 2.0 V at room temperature.

9. The lithium ion battery of claim 1 wherein the coating composition comprises less than about 1 weight percent of the positive electrode material.

10. A method for forming the coated positive electrode active material of claim 1, the method comprising heating the lithium rich metal oxide with an aluminum precursor coating to a temperature from about 500°

C. to about 800°

C.

11. The method of claim 10 wherein the aluminum precursor coating comprises aluminum hydroxide.

12. The method of claim 10 wherein the coated positive electrode active material formed comprises from about 0.1 to about 0.75 weight percent of an aluminum oxide coating composition.

13. The positive electrode material of claim 1 wherein the lithium metal oxide can be approximately represented by a formula of xLi₂M′

O₃.(1−

x)LiM″

O₂, where M′

represents one or more metal ions having an average valance of +4 and M″

represents one or more metal ions having an average valance of +3, and 0<

x<

1.

14. The positive electrode material of claim 1 wherein the irreversible capacity loss is reduced by at least about 15% relative to the irreversible capacity loss of the uncoated lithium metal oxide.

15. The positive electrode material of claim 1 having a specific discharge capacity of at least about 270 mAh/g with a discharge rate of C/3 when discharged from 4.6V to 2.0 V at room temperature.

16. The positive electrode material of claim 1 having a specific discharge capacity of at least about 245 mAh/g with a discharge rate of C/3 at the 50th charge/discharge cycle when discharged from 4.6V to 2.0 V at room temperature.