While the shift to electric vehicles may be exciting, it will also leave us with thousands upon thousands of tonnes worth of unused batteries.
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It is 2035, and electric cars have taken over the roads. The European Union has already banned the sale of petrol and diesel cars to accelerate the transition to cleaner mobility and reduce climate change. Although electric vehicles emit no carbon dioxide while being driven, their rechargeable batteries can cause environmental and social problems. They are made up of rare and costly metals. They are also difficult to recycle once they have outlived their useful life.
Ordinary lithium-ion battery are composed of hundreds of individual cells and can weigh hundreds of kilograms. While the Nissan Leaf’s battery pack contains 192 pouch cells and the Tesla Model S has 7,104 cylindrical cells each, they are all packaged into modules that can be screwed, welded, and glued together in order to be managed as one unit. Researchers, carmakers, and battery companies are working together to prevent batteries from ending up in landfills.
The primary goal of recyclers is to extract valuable metals and minerals from the cells. It is difficult and dangerous to reach these materials. After removing the steel case, the battery pack must be removed from the cells. If heated, the electrolyte (a liquid that moves lithium ions between cathode & anode) can catch fire and explode. Recyclers can only safely extract the cobalt, nickel, copper and nickel from the pack once it has been taken apart.
Cobalt is used in the cathode. The rare, bluish-grey metal is mainly sourced from the Democratic Republic of Congo. There, miners work under dangerous conditions. The human rights violations, the shortages in the supply chain, , and fluctuating prices have deterred the world’s largest electric car manufacturers from moving away cobalt.
This raises the question whether recyclers will still be motivated to dispose of older battery types that lack the most valuable components. Jenny Baker, a Swansea University energy storage expert, says that recycling and recovering them becomes less attractive when you switch to more sustainable and lower-cost materials. This is similar to the dilemma with consumer electronics: It’s often cheaper to purchase a new phone than to fix it or recycle it.
When EVs were rare, recycling wasn’t an issue. By 2020, there were 11 million electric vehicles and buses on the roads. According to the International Energy Agency, that number could rise to 145 million by 2030. This figure does not include two- and three-wheelers.
The number of used batteries will continue to rise as EV sales increase. Based on the sale of a million vehicles in 2017, the Faraday Institution in the UK, which is a research organization specializing in battery technology, estimates that around 250,000 tonnes of unprocessed batteries will be gone by the time they reach their end in the next 15 to 20 year. This is equivalent to half a million cubic metres of used batteries. It’s enough to fill 200 Olympic-sized swimming pool. However, some of these batteries may retire in the event of a crash or be reused by other industries, and then recycled later.
According to Circular Energy Storage, a London-based consultancy, the global capacity for recovering used batteries’ raw materials is 830,0000 tonnes per year. Hans Eric Melin, managing director of Circular Energy Storage in London, says that a lot of this material is located in China. It is not available for export as China bans the import of used batteries. More than two-thirds of the supply chain lithium-ion battery batteries is occupied by Chinese companies. Melin says that the ban can be lifted by using recyclers from Southeast Asia.
Europe is slowly catching up in battery production and recycling. Car manufacturers are leading the charge to reclaim valuable materials. The IEA predicts that recycling could meet as much as 12 percent of the EV market’s demand for cobalt, nickel, copper, and copper by 2040.
In a pilot phase, the Volkswagen Group, which includes Audi, Porsche, and other brands, is recycling as many as 3,600 batteries per year at its new Salzgitter plant, north Germany. The market is also being explored by mineral processors: Neometals, an Australian minerals company, has teamed up with SMS group, a German company, to build a large-scale battery-shredding plant. This partnership was made in Germany, which is the largest country in Europe.
Bo Normark, an industrial strategist at EIT InnoEnergy (a EU-funded sustainable innovation accelerator), says that recycling is urgently needed. Because lithium-ion batteries last more than ten year, it will take some time for them to accumulate. Normark says that recycling scraps from the battery industry will become a necessity long before then. This includes trimmings and any other waste that is generated during manufacturing or batteries that fail quality testing.
The industry must rethink how it approaches battery recycling before it can scale up. The current recycling techniques are not sophisticated and can only extract high-value materials from cells. Gavin Harper, a University of Birmingham research fellow, uses the analogy of the Snakes and Ladders board game to show how lithium-ion battery are produced and recycled. The player begins with the raw materials at the base of the board and moves up the board to make a battery. He or she aims to reach the top of each board with a fully-recycled battery. The snakes allow a player to slide down through several squares of the board. They are different in length and correspond with various recycling methods.
Recyclers typically make a powdery mixture from the anode and cathode materials of used batteries. This is called the “black mass”. Harper says that this is the first slide on a snake in the board game analogy. To extract the valuable components of the black mass, there are two options. Pyrometallurgy is a method that involves melting the black mass in a furnace using fossil fuels. This is a cheap way to make manganese, graphite, lithium, and aluminium. However, it’s expensive.
Hydrometallurgy is another method that leaches metals from the black mass through the use of acids and other solvents. Harper claims that this method would result in a shorter snake on the board game because it can recover more material. You fall back, but not as many squares, as with pyrometallurgy. However, the process consumes lots of energy and creates toxic gases and waste.
Harper says that the idea of direct recycling is “the Holy Grail” for recycling. However, it only goes a small way. The cathode is taken out of the battery cells, separated and then regenerated chemically. Finally, it is placed back into a cell. It’s definitely possible, and it has been shown to work. Harper says that there is a fervent effort to research techniques. He refers to the ReCell Center which is an American research collaboration focused upon battery recycling and funded by US Department of Energy. Similar efforts are underway across Europe and Britain.
Some companies, startups, and research institutes are still trying to figure how to recycle lithium-ion battery cells. Others are developing cheaper, more sustainable batteries. Chinese companies CATL and BYD already produce lithium iron phosphate batteries that are less toxic and more cost-effective. They also plan to use sodium-ion battery, which uses abundant sodium rather than the relatively rare lithium, as the next generation of EV-batteries.
Baker believes that recycling should not be seen as a way to extract precious metals from a battery pack. Baker says that the value of a battery pack is more than just its elements. It’s also the way they were engineered and assembled. To put it another way, in order to make battery recycling work, we may need to redesign the batteries completely.