By Kent Griffith
May 9, 2023 | Something on the order of 3 TWh of batteries are going to be produced annually by 2030. This translates to roughly 12 million kilograms of battery cells. Battery lifetimes are increasing and second-life applications may further extend the time from manufacture to end-of-life, but, ultimately, large scale recycling of battery materials is going to be required. While manufacturing scrap dominates today, it is estimated that recycled batteries will contribute half the feedstock for battery manufacturing by just 2035. Toward that goal, the community is working quickly to build a sustainable battery supply chain. Central figures in this rapidly changing space convened at the 40th International Battery Seminar and Exhibit in Florida earlier this year to share their latest developments.
Lithium-ion battery recycling has not historically been a large market. It has also focused on cobalt, copper, and to some extent nickel. The rising quantity of nickel and rising price of lithium in recent years has motivated their recovery. The scale of global EV adoption is fundamentally changing the calculus to the point of emphasizing recovery of more challenging and lower value materials like graphite and the electrolyte components. While some large and established battery companies are likely to get involved, there is also a unique gap for start-ups to fill with new, more efficient, and more environmentally friendly recycling methods. The goal is to use less energy and generate less waste with fewer steps and fewer harmful chemicals while returning as much of the cell as is feasible to battery-grade chemicals. Although many processes are a mixture of steps, the general hierarchy is that direct recycling is more resource efficient than hydrometallurgy, which is more efficient than pyrometallurgy. Pyrometallurgical processes produce metals that require further processing into battery chemicals while hydrometallurgical techniques can convert black mass into battery chemical feedstocks. In the case of direct recycling, it may be possible to return electrode materials themselves.
One emerging company at the International Battery Seminar was Botree Cycling. CEO Xiao Lin discussed the firm’s role as an engineering design, equipment, and operation company service provider. Botree has developed strategies tailored for individual countries and pyro or hydro approaches that can target metal sulfate or pre-cathode active material (pCAM) outputs. Another development is the pre-extraction of lithium from black mass with better than 92% lithium recovery and 98% lithium selectivity while losing virtually no cobalt or nickel. The method is targeted for the European market, whereas Lin said the Asian market will extract lithium at the same time as cobalt and nickel while making the pCAM in the same factory. He does not believe graphite recycling to a battery grade input is feasible in the short term, but he did note that it will be required in Europe to meet regulations and may go into alternative graphite applications if the quality cannot meet the stringent requirements of battery manufacturers. Lin said that direct recycling in the form of separation and regeneration will be suitable for production scrap and slurry. Botree is building a 5000 ton/year demonstration plant in Germany for NMC and LFP recycling. Lin’s book Recycling of Power Lithium-Ion Batteries: Technology, Equipment, and Policies is available now.
RecycLiCo, represented at the International Battery Seminar by Shaheem Ali, was previously known as American Manganese. They have a developed a proprietary hydrometallurgical recycling process and now have a demonstration plan in Vancouver, Canada, processing 500 kg/day. According to Ali, their process can recover up to 99% of the battery metals and their recycled materials have gone into industry qualified NMC811 cathodes with more than 200 mAh/g reversible capacity. RecycLiCo intends to co-locate with battery manufacturers for on-site recycling. The co-founder of RecycLiCo, Joey Jung, recently published a book on Hydrometallurgical Recycling of Lithium-Ion Battery Materials.
OnTo Technology has been around since 2004 but is ready to ramp up operations as the battery recycling market is set to take off. Their president, Steven Sloop, detailed how OnTo has developed supercritical carbon dioxide processes for both battery deactivation and, under more mild conditions, battery rejuvenation. Deactivation is an important piece to the economics and safety of recycling because it lowers the hazards and costs associated with shipping spent batteries to recycling facilities. Injection and soaking of carbon dioxide converts reactive conductive lithium into relatively inert lithium carbonate. The company is also working on direct recycling wherein they autoclave a concentrated lithium solution with the electrode material to regenerate a functional cathode that can go back into new cells. Sloop estimates that direct recycling will be at least 10 times lower cost than pyro and hydro methods with a cost of just $3.60 per kg compared to $35–40 per kg for incumbent technologies. OnTo Technology is also proposing co-location with gigafactories to save a step in material transfer.
Not all emerging battery recyclers are start-ups. Korea Zinc is a prime example of an established metal recycler that is making a foray into the battery space. As introduced by HaSung Park, Korea Zinc has more than 20 products in its portfolio and is the world’s largest recycler of zinc, lead, silver, and indium. It has recently moved into battery recycling through the acquisition of e-scrap collector and recycler Igneo as well as two joint ventures with LG Chem. One JV will produce nickel sulfate, a precursor for nickel-rich lithium-ion battery cathodes. The second JV is for a hydrometallurgical black mass recycling plant than will inject additional nickel sulfate from the former company to create their final products. Korea Zinc is also producing copper foil for batteries and expanding from 13,000 tons/year today to 120,000 tons/year by 2030. They are planning commercial mass production for battery recycling in the US and Europe in 2026.
Recyclers and collectors are not the only companies with important roles in battery recycling. An outstanding challenge for the community is material identification and sorting. Efforts are underway to standardize cell labeling, but there will always be a need for chemical composition analysis throughout the process. Jenny Nelson from Agilent presented the company’s elemental analysis instrumentation with a focus on inductively-coupled plasma optical emission spectroscopy (ICP-OES) for the determination of impurities down to the single parts per billion level in virgin battery materials through to electrodes, black mass, and recycled content. Agilent has a number of application notes available for processing specific battery materials and components such as graphite, lithium carbonate, and electrolyte salts. For an even higher sensitivity of impurity detection, they have inductively coupled plasma mass spectrometers (ICP-MS) that can do compositional analysis down to below part per trillion levels.
It is promising to see new companies emerge and older recyclers pivot into the battery space. Many people in the broader sustainability and government sectors worry about what will happen to all these spent batteries as EV growth takes off. One perhaps surprising takeaway from the recycling community at the International Battery Seminar was that the main challenge they face at this time is the lack of batteries to recycle!