New, Low-Cost Method for Lithium Ion Battery Recycling
There is growing interest in the recycling of used lithium ion batteries as the world accumulates more used batteries, both from an environmental and commercial perspective. Lithium ion batteries contain valuable materials like aluminium, copper, cobalt, and lithium. In an attempt to extract these from used batteries, companies and research institutes have established pilot lines based on traditional hydrometallurgical methods. The typical hydrometallurgical method, however, is a convoluted process that makes the recycling process too complex and expensive. It also involves the use of chemicals like sulfuric acid, sodium hydroxide, and sodium carbonate, and generates secondary pollution.
Despite these obvious limitations, the global lithium ion battery recycling market was valued at US$2.1 billion in 2018 with the hydrometallurgical process segment taking a lion’s share of 42%. As more widespread adoption of battery recycling practices is expected in the near future, industry estimates have placed market growth at a CAGR of 26.5% to reach US$13.6 billion by 2026. A novel recycling method that is simpler and more cost-effective may be a game-changer in this context.
In this invention, we disclose a new approach for lithium ion battery materials recycling. This method comprises mechanical pre-treatment of used batteries and redox targeting-based materials leaching and separation processes. The latter is a novel process that is able to address the issues relating to traditional hydrometallurgical methods. It makes the recycling process simpler, reduces secondary pollution, lowers cost and involves an apparatus that is much more compact and efficient.
The mechanical process of this method is no different from existing ones. However, in the redox targeting-based leaching and separation processes, the cathode material is scraped from the cathodic electrode and immersed into a redox electrolyte to leach out lithium ion. The solution is circulated into a cell for regeneration. Meanwhile, lithium ion migrates into the electrolyte at the counter electrode compartment. This method allows the leaching and separation processes to proceed simultaneously and continuously with minimal secondary pollution. The leaching reagents can also be regenerated and reused. It therefore provides a low-cost and environmentally-responsible method for lithium ion battery materials recycling. By dramatically simplifying the recycling process presently adopted by the industry, it promotes greater profit margins in the battery recycling business.