Sodium layered oxide as cathode material for sodium ion battery

Patent metadata

Field	Value
Publication number	US-10601039-B2
Application number	US-201515742847-A
Country	US
Kind code	B2
Filing date	Jul 15, 2015
Priority date	Jul 15, 2015
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

A mixed oxide of sodium and transition metals having the formula (1):

Na x [Mn a Ni b Co c ]O 2+y   (1)

wherein: 0.5≤x≤0.9, −0.1≤y≤0.1, a+b+c=1, 4a+2b+3c=4−x+2y, and 0<c≤0.5. Further a process for producing such a mixed oxide, a positive electrode including such a mixed oxide and a sodium ion secondary battery including such a positive electrode.

First claim

The invention claimed is:

1. A mixed oxide of sodium and transition metals having the formula (1):
Na x [Mn a Ni b Co c ]O 2+y   (1)

wherein:
0.5≤x≤0.9,
−0.1≤y≤0.1,
a+b+c=1,
4a+2b+3c=4−x+2y,
0<c≤0.5,
a>0,
b>0, and
wherein the mixed oxide is a layered oxide having a P2 crystal structure.

2. The mixed oxide according to claim 1 , wherein 0.60≤x≤0.80.

3. The mixed oxide according to claim 1 , wherein c>0.30.

4. The mixed oxide according to claim 1 , wherein 0.35≤a≤0.55.

5. The mixed oxide according to claim 1 , wherein 0.05≤b≤0.25.

6. A process for producing a mixed oxide of sodium and transition metals according to claim 1 , comprising the steps of:
(a) preparing an aqueous Solution 1 containing a mixture of soluble salts of Mn, Ni and Co;
(b) preparing an aqueous Solution 2 containing a soluble sodium source;
(c) introducing Solutions 1 and 2 simultaneously into a receiving vessel to induce precipitation, wherein the receiving vessel is provided in advance with water;
(d) recovering the precipitate obtained in step (c), and optionally washing it with distilled water;
(e) drying the precipitate obtained through step (d);
(f) combining, in an inert atmosphere, the dried material obtained through step (e) with a further source of sodium in an amount enabling the required stoichiometry for a final composition according to formula (1) of claim 1 to be reached;
(g) calcining the mixture obtained through step (f) for a temperature of at least 700° C. and at most 1000° C. for a time of at least 1 hour and at most 24 hours.

7. The process according to claim 6 , wherein the transition metal salts recited in step (a) include nitrates.

8. The process according to claim 6 , wherein the sodium source recited in steps (b) or (f) includes sodium carbonate (Na 2 CO 3 ).

9. A positive electrode for a sodium ion secondary battery comprising the mixed oxide of sodium and transition metals according to claim 1 .

10. A sodium ion secondary battery having the positive electrode for a sodium ion secondary battery according to claim 9 , a negative electrode having a negative electrode active material, and an electrolyte.

11. The mixed oxide according to claim 1 , wherein 0.65≤x≤0.75.

12. The mixed oxide according to claim 1 , wherein c>0.40.

13. The mixed oxide according to claim 1 , wherein c≥0.45.

14. The mixed oxide according to claim 1 , wherein a≤0.45.

15. The mixed oxide according to claim 1 , wherein b≤0.15.

Assignees

• Toyota Motor Europe
• Centre Nat Rech Scient

Inventors

• Yoshida Jun
• Delmas Claude
• Guignard Marie
• Carlier-Larregaray Dany

Classifications

• C01P2006/40

  Electric properties · CPC title

• C01G53/50

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• H01M10/054

  Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title