Process for the preparation of precursor compounds for lithium battery cathodes

Patent metadata

Field	Value
Publication number	US-11695169-B2
Application number	US-202017604002-A
Country	US
Kind code	B2
Filing date	Apr 17, 2020
Priority date	Apr 19, 2019
Publication date	Jul 4, 2023
Grant date	Jul 4, 2023

Abstract

The present disclosure concerns the production of precursor compounds for lithium battery cathodes.
Batteries or their scrap are smelted in reducing conditions, thereby forming an alloy suitable for further hydrometallurgical refining, and a slag. The alloy is leached in acidic conditions, producing a Ni- and Co-bearing solution, which is refined.
The refining steps are greatly simplified as most elements susceptible to interfere with the refining steps concentrate in the slag. Metals such as Co, Ni and Mn are then precipitated from the solution, forming a suitable starting product for the synthesis of new battery precursor compounds.

First claim

The invention claimed is:

1. A process for the preparation of a precursor compound for the synthesis of cathode material for rechargeable lithium batteries, comprising the steps of:
reducing smelting of a metallurgical charge comprising spent rechargeable lithium batteries or their scrap containing Ni, Co, Al, Li, F, either one or both of Cu and Fe, and fluxing agents, thereby producing an alloy comprising the major part of the Ni, Co, and Cu, at least part of the Fe, and depleted in Al, Li and F;
leaching the alloy in a mineral acid, thereby obtaining a Ni- and Co-bearing solution also containing either one or both of Cu and Fe;
refining the Ni- and Co-bearing solution, by removing the therein contained Cu and Fe, thereby obtaining a purified Ni- and Co-bearing solution; and
simultaneous precipitation of Ni and Co from the purified Ni- and Co-bearing solution as hydroxides or salts, by heat treatment, crystallization, or addition of hydroxide or carbonate, thereby obtaining a solid suitable for the synthesis of cathode material for rechargeable lithium batteries.

2. The process according to claim 1 , wherein the process is free from a solvent extraction or ion exchange step in which Ni and/or Co are extracted from the Ni- and Co-bearing solution.

3. The process according to claim 1 , wherein the alloy is granulated, atomized or comminuted before the leaching step.

4. The process according to claim 1 , wherein the mineral acid is H 2 SO 4 .

5. The process according to claim 1 , wherein the step of leaching is performed under oxidizing conditions.

6. The process according to claim 5 , wherein the step of leaching is performed under oxidizing conditions using O 2 or H 2 O 2 as oxidizing agent.

7. The process according to claim 5 , wherein the removal of Cu in the refining step is performed by precipitation.

8. The process according to claim 7 , wherein the removal of Cu in the refining step is performed by precipitation using cementation with the alloy.

9. The process according to claim 1 , wherein, in the step of leaching, Co is leached selectively versus Cu by control of pH and redox potential during leaching.

10. The process according to claim 1 , wherein the removal of Fe in the refining step is performed under oxidizing conditions leading to the precipitation of a Fe 3+ compound.

11. The process according to claim 10 , wherein the removal of Fe in the refining step is performed under oxidizing conditions leading to the precipitation of a Fe 3+ compound using O 2 or H 2 O 2 as oxidizing agent.

12. The process according to claim 1 , wherein, between the steps of leaching and precipitation, the ratio of the elements Ni to Co to Mn in the purified Ni- and Co-bearing solution is adjusted to a preset value by addition of any one of these elements as a soluble compound.

13. The process according to claim 1 , wherein said precursor compound is a solid Ni- and Co-containing product and said solid suitable for the synthesis of cathode material for rechargeable lithium batteries is the same solid Ni- and Co-containing product.

14. The process according to claim 13 , wherein the Ni- and Co-containing product also contains Mn, wherein, during the simultaneous precipitation of Ni and Co from the purified Ni- and Co-bearing solution, also a Mn-oxide and/or Mn-hydroxide and/or a Mn-salt is precipitated, by heat treatment, crystallization, or addition of a source of hydroxide ions or carbonate ions, thereby obtaining said Ni- and Co-containing product also containing Mn.

Assignees

• Umicore Nv

Inventors

• Oosterhof Harald
• Scoyer Jean
• Scheunis Lennart
• Klaasen Bart
• Callebaut Willem

Classifications

• C22B47/00

  Obtaining manganese · CPC title

• H01M6/52

  Reclaiming serviceable parts of waste cells or batteries {, e.g. recycling} · CPC title

• C22B1/005 Primary

  Preliminary treatment of scrap (C22B1/02 - C22B1/26 take precedence) · CPC title

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title

• C22B7/007

  by acid leaching · CPC title