Lithium Battery Recycling Vital for Sustainable Electronics Market, Experts Say
The first tests involving the use of lithium and energy generation were carried out in 1912 by physicist Gilbert Newton Lewis. However, lithium-ion batteries, as we know them today, only began to appear in electronic products in the 1970s. The invention represented an important advance for the sector. Previous models, such as the successful lead-acid and nickel-cadmium models, were heavier and had less energy storage capacity. Today, lithium-ions are what power your smartphone, your computer and, most likely, will be responsible for powering your car in the future.
Electric car sales have seen a significant boost in recent years, up 41% in 2020 and 108% in 2021. By 2023, 14% of all new cars sold worldwide were electric. In Brazil, the sector is showing strong signs that it is here to stay. Even with the return of taxes on electric imports, January 2024 saw the registration of 12,000 electrified vehicles, 167% more than in the same period in 2023. The Chinese company BYD plans to invest R$5.5 billion in Camaçari, Bahia, in a project that includes the exploration and processing of lithium for batteries. For Ricardo Bastos, president of the Brazilian Electric Vehicle Association (ABVE), Brazil will be a producer of batteries for electric vehicles in less than ten years. With the growth of this market, interest in businesses involving its most important component, which is precisely the battery, also grows. A study by McKinsey Battery Insights projects that the entire lithium-ion battery supply chain, from mining to recycling, could grow by more than 30% per year through 2030.
An important factor in the BEV (Battery Electric Vehicle) narrative is that it is sustained by being strongly linked to a broader environmentalist agenda: the transition to sustainable energy matrices. The model emerges in the midst of a climate crisis and at a time when global authorities are seeking alternatives to mitigate the effects that are already being observed. BEVs are marketed as a clean, carbon-free form of transportation, an urgent demand in the modern world. In order to avoid becoming a trade-off between one problem and another, the batteries in these cars must be disposed of in a way that does not harm the environment at the end of their useful life, which has been a problem for researchers and environmentalists. Disposing of lithium batteries can have a negative impact on the environment. Composed of heavy metals and toxic chemicals, lithium batteries are not biodegradable and can last hundreds of years after their useful life has ended. Furthermore, if the process is done improperly, it can contaminate groundwater with the chemicals from the metals. Recycling then becomes a crucial process for this market. Researcher Amilton Botelho, a postdoctoral fellow who is part of the Larex team – the Recycling , Waste Treatment and Extraction Laboratory – at the Polytechnic School of USP , explains that recycling processes also have bottlenecks, but that the laboratory has made progress on this issue.
Problems and challenges
According to the expert, a lithium-ion battery lasts an average of five years and is made up of several small cells, where the two poles of the battery that establish an electric current are located, the anode and the cathode. This is where the lithium and graphite are found. Together, the cells form a pack, a larger package. The first step in the recycling process is to break down this package, in search of a cell in a reasonable state of conservation that can be reused, creating a second-life battery. Second-life cells are usually used to store energy from photovoltaic panels. The rest is sent for recycling. Botelho says that the most traditional methods involve thermal reactions at up to a thousand degrees Celsius. The graphite contained in the battery turns into CO2 and the plastic too, worsening the greenhouse effect. In addition, these are processes that serve small portions of the producer market, as they work for only a few types of lithium batteries.
“There are several problems to be solved in this situation. One of the biggest challenges for efficient recycling is to ensure that just one process, a single method, can meet the needs of different types of battery models. There are several types of batteries, from different companies and that serve different markets. How can we recycle everything in a single industrial process? This is a puzzle that we were able to solve with our research; we meet all these demands with our process,” he explains.
Another issue is the high energy consumption, which makes the operation very expensive and not very attractive financially. The alternative developed at USP is more efficient and cheaper. “We chose a processing route in an aqueous medium, called hydrometallurgy, which allows us to operate at much lower temperatures, around 90° Celsius. We achieved 95% recovery of the materials, and we were able to recover the plastic fraction of the battery and also the graphite,” he says.
The operation developed at Larex restores all the battery components, the anode, the cathode, the coating and the plastic parts, thus recovering all the precious metals and valuable items from the object. In addition, the 5% of waste left over from the process can be reused in other industrial processes. “Industrial processes will always generate waste. The idea is that new processes will be more efficient, develop new technologies, but that you can also reuse the waste that is generated. It is not just a match zero industrial process, that is, without carbon emissions. But rather a process that leaves useful waste for other areas of the industry”, he explains.
Regarding the applicability of the process on an industrial scale, Botelho says that his team is making progress. “The entire route developed in the laboratory is now being applied on a pilot scale. We have gone from a 100ml scale to a 20- to 60-liter scale. In this sense, we are the first in the world to achieve these results with such a volume of material,” concludes the researcher.