Urban mining: how battery recycling is creating a new source of domestic cobalt

Main image: Gavin Rech, area sales and technical manager at TOMRA Mining. Credit: TOMRA Mining

Main video credit: Shutterstock.AI

C obalt extracted from mined ore eventually enters batteries, but when those batteries reach the end of their lives, their critical minerals can become an urban-mining resource. That opportunity is becoming more significant as the market for cobalt expands.

Demand for cobalt exceeded 200,000t for the first time in 2024, and forecasts expect total cobalt demand to grow at a 7% compound annual growth rate to 2030.  

The demand surge is driven by scaling battery production for electric vehicles (EVs) and portable electronics. Against the widening supply gap, producers are looking to new sources of critical minerals – and batteries themselves are becoming an essential feedstock. 

Battery cells can be shredded or crushed to produce black mass, which is quietly becoming a closely monitored cobalt feedstock for battery producers. Depending on chemistry, black mass can contain lithium, nickel, manganese and cobalt (the cathode), alongside less valuable graphite (the anode) and trace quantities of aluminium, copper and iron. Separating these offers a new, domestic supply of critical minerals, against a backdrop of international uncertainty.  

This uncertainty is particularly apparent in cobalt. Around 70% of the world's mined cobalt originates in the Democratic Republic of Congo, leaving battery manufacturers exposed to political, labour and export policy risks, alongside ethical questions. Dependency has already translated into volatility, and cobalt prices have experienced dramatic swings – EV scaling saw prices skyrocket in 2016, before crashing in 2018, while a subsequent surge peaked in March 2022, before crashing 70% by January 2025.

Battery recycling could therefore offer a much-needed cobalt supply source. Hydrometallurgical leaching of black mass can achieve high selectivity and research from Argonne National Laboratory's AMUSE model has predicted cobalt recovery rates exceeding 99%.

GlobalData’s report, drawing on International Energy Agency (IEA) data, puts secondary cobalt supply and reuse at 26,000t in 2024, rising to 39,000t by 2030 and 82,000t by 2040 under the IEA’s stated policies scenario. In the same scenario, total cobalt demand rises from 221,000t in 2024 to 314,000t in 2030 and 330,000t in 2040. 

The question then is not whether there is a cobalt source but how scalable a solution battery recycling is.   

The industry is optimistic that, with policy support and infrastructure overhaul, battery recycling for cobalt could be a profitable means of supporting domestic demand. Materials recycling group leader at Argonne Jeffrey Spangenberger says battery recycling represents “a huge potential opportunity for a new business”, particularly in supply-insecure cobalt. “There is job creation and money to be made, and it is also a national security issue,” he adds.

Lithium-ion (Li-ion) batteries are among the most common rechargeable batteries. The most common chemistries are nickel manganese cobalt (NMC), lithium iron phosphate (LFP), lithium cobalt oxide (LCO), lithium manganese oxide (LMO) and nickel, cobalt and aluminium (NCA). All except LMO and LFP contain cobalt.  

NMC is the most common battery chemistry in EVs, and Anton Zorin, head of research at UK-based Li-ion battery recycling company Recyclus Group, notes that “because it is mass manufactured, we are also starting to see it in certain consumer electronics”. He adds that LCO is popular in consumer electronics, particularly in higher-end laptops and phones, while NCA was “an old EV chemistry mix”.

The cobalt opportunity is therefore significant. Located in the cathode, cobalt is typically bound as a lithium metal oxide compound, coated onto an aluminium foil current collector. In NMCs, the type of battery indicates the cobalt contents – NMC 111 is 1:1:1 for its three metals; NMC 532 is 20% cobalt, as is NMC 622, while NMC 811 is 10%.  

Zorin points to NMC 955 as “the latest battery chemistry coming to the market”, which he explains is 90% nickel, 5% manganese and 5% cobalt. Quantities differ according to chemistry too – around 24% of LCO battery weight is made up of cobalt.  

Battery chemistries matter because each one carries a different mix and concentration of critical minerals, which determines the economics of recycling end-of-life cells. Despite being physically smaller, LCOs offer the most cobalt-rich feedstock, while the high nickel and cobalt content of NMC and NCA packs makes them the most valuable chemistries once shredded.

Before being shredded, end-of-life battery packs are collected and sorted by battery chemistry to avoid cross-contamination. Packs are disassembled into modules and then cells, which are stabilised and comminuted to produce black mass, which Zorin describes as “a black, dusty powder […] with an almost flour-like consistency”.  

Metals are then separated. Hydrometallurgy is generally preferred for black mass, because it achieves higher selectivity and purity when recovering individual metals including cobalt, nickel, manganese and lithium. In comparison, pyrometallurgy’s high-temperature smelting recovers cobalt and nickel less selectively, often losing lithium and manganese to the slag, and requires additional downstream refining to reach battery-grade metals.

UK-based black mass-processing company Altilium uses hydrometallurgy to extract critical minerals from shredded batteries. Chief technical officer Benjamin Wickham explains that the process begins by using mineral acid for leaching. “We then go through a strategic staged impurity removal process, followed by refinement of key materials in order of a reactivity series that we have identified. Then it is about recovery of all those refined fractions,” he explains.  

On impurities, he notes that Altilium refines out copper as “a relatively pure stream”, because it lends itself to easy recycling. Iron, aluminium, fluorides and phosphates are also taken off in the impurity removal stage, he says.   

Refinement of key materials is conducted using solvent extraction, used when metals behave similarly. “Solvent extraction is a process that enhances that contrast or the selectivity of separability of metals,” explains Wickham. “It is used to refine a pure manganese stream, followed by a cobalt stream, followed by a nickel stream, and then we opt to precipitate out lithium carbonate at the end of our process as a low-difficulty way of solidifying and isolating lithium.”

Before black mass is comminuted or separated, however, there is an upstream challenge casting a shadow over cobalt recovery – battery collection. 

Batteries are collected from consumers, fleet operators or original equipment manufacturers, but networks are fragmented and minimal. Global end-of-life Li-ion battery volume was projected at around 900,000t in 2025, but recycling rates remain under 10%.  

The collection challenge is multifaceted: a lack of infrastructure combined with safety and logistics costs and an EV battery supply lag means networks have been slow to grow and consolidate.  

One pain point is thermal runaway risk in damaged or defective batteries, which are considered class nine hazardous goods. ‘Unknown state’ cells are also treated as carrying significant thermal risk, requiring specialist handling and transport including UN-certified, explosion-resistant metal containers such as Recyclus Group’s LiBox. 

Zorin explains that “unless the originator of the pack can guarantee that it is 100% burnt out, and there is absolutely zero charge in it, [damaged defective packs] must be transported according to the ADR [European Agreement concerning the International Carriage of Dangerous Goods by Road] regulations.”  

Logistics arrangements must assume that the pack contains as much power as it would if it was new, and high safety standards “make transport very expensive and limited to the companies that are compliant with these ADR regulations”, says Zorin.

The risk translates into the recycling centre too. Damaged or defective batteries cannot be shredded and processed like intact end-of-life cells, as residual charge, compromised casings and unstable internal chemistry increase the reignition or explosion risk during comminution. Instead, these batteries require separate handling and storage.

Recyclus Group’s discharge and dismantle crew treat high-risk thermal runaway batteries as a “priority” until they have been disassembled. “We tend not to store these batteries,” says Zorin. “Once it arrives to our site, we have a trained high-voltage crew that can assess to what extent the battery is burnt out, disassemble it and it can go to the shredder very quickly.” 

Safety is not the only logistical obstacle to collection, however. Currently, Recyclus Group, Altilium and other operators in the black mass space primarily use EV batteries, despite the potential opportunity presented by consumer electronics. E-waste is “a really interesting proposition”, according to Wickham, but remains a relatively under-explored market, not because of chemistry or value but because of collection economics.  

While EV battery packs weigh between 300kg and 600kg, consumer electronics battery packs are much lighter – smartwatch batteries can weigh as little as 2g, while even large laptop batteries are rarely heavier than 600g. Thus, without robust networks and subsidies, collection and processing costs often exceed the value of recovered materials.  

Yet Spangenberger sees this as a missed opportunity. “Cobalt is the biggest contributor in chemistries that go on our cell phones and our laptops – there is a lot of cobalt in those batteries.” 

“Everybody has cell phones and laptops in their houses”, he adds. “There is a huge opportunity to get these [batteries] and it is a very profitable material to process because of all the cobalt.” 

According to a report by the UN’s Global E-waste Monitor, around 22.3% of the 62 million tonnes of e-waste generated worldwide in 2022 was formally collected and recycled. This equated to an estimated 34,000t of cobalt.

Government regulation and subsidy support is a defining factor for collection networks and the broader battery recycling industry.  

The EU has adopted an extensive battery recycling policy. Its Extended Producer Responsibility (EPR) for batteries dictates that battery manufacturers or importers bear the financial and physical responsibility of waste management (although individual countries enforce compliance through their own localised schemes).  

In 2023, the EU also introduced its revised Battery Regulation, which set escalating minimum recycled-content requirements – from August 2031, new EV, industrial and starter batteries sold in the EU must contain at least 16% recycled cobalt, 6% recycled lithium and 6% recycled nickel, rising to 26%, 12% and 15%, respectively, from 2036.  

Elsewhere, in China, the Ministry of Industry and Information Technology’s new 2026 rules mandated ‘vehicle-battery co-retirement’, meaning end-of-life vehicles must be scrapped with batteries intact. A national digital traceability platform is also used to track batteries from production to dismantling, and EPR obligations place responsibility decisively on manufacturers. The rules took effect on 1 April 2026. 

In the US, the Inflation Reduction Act’s clean vehicle credit previously required an escalating share of battery critical minerals to be extracted, processed and recycled in North America or a free-trade agreement partner country. However, the clean vehicle credits were terminated for cars acquired after 30 September 2025 following the passage of the One Big Beautiful Bill Act. The US has no overarching EPR-equivalent scheme and instead relies on state-by-state regulation.   

Zorin says that government support will require flexibility, as profit potential differs based on battery chemistry and shifting commodity prices. For example, LFP batteries do not contain nickel or cobalt, meaning the economics of LFP battery recycling is squeezed. “The payables are massively reduced to the point where they are almost negative. If LFP keeps growing at the rate that it is, the UK Government will have to either underwrite a gate fee or underwrite the buying of a black mass at a base, so that recycling is still economically viable,” he says.  

Improving government incentives for battery recycling around the world have also sparked investor interest, although Spangenberger says there has been fluctuation. “I see a lot of investors in the area, but maybe not as much lately. In the early 2020s, there was a lot of interested investors.” He notes that the investment pattern aligns roughly with EV uptake, which began slowing in 2023. 

Wickham is also positive about government support and investment. He points to Altilium’s $25m (£18.5m) funding from the Department of Business and Trade, which the company received to support its ACT3 commercial facility. 

“We have to match fund that with private financing, but we are lucky that this space is very much a sweet spot,” he says. “The government has recognised the industrial strategy and the advanced manufacturing plan and then we have the critical mineral strategy. We are in a pretty good place.”  

The technology is ready, then, to secure domestic cobalt production from black mass made from end-of-life batteries. Policy support and investment are following, but fragmented and expensive collection presents a limiting factor. Ultimately, increasing demand and currently low recycling rates mean cobalt supplies from recycling will be inherently inadequate.  

However, Wickham points out that “every tonne of cobalt recovered from recycling is a tonne equivalent of mining that is either saved or deferred.”