With the change in traffic to electromobility, the number of batteries to be reused will increase sharply. The raw materials it contains are valuable and must be recycled for a sustainable future. However, the recycling process leads to some challenges that make it more difficult
The life cycle of EV batteries
The most common lithium-ion batteries are used, which can deliver good performance in the car for up to 10 years. At the latest from there, the performance of the battery is too bad for further use in the vehicle. They will be removed from the car and reused as, for example, stationary storage for photovoltaic systems or other purposes of energy storage. If their performance is even too poor for this, they are sent to a recycling process.
What are EV batteries made of?
A lithium-ion battery weighing around 500 kg contains roughly 100 kg graphite, 32 kg nickel, 11 kg cobalt, 10 kg manganese, and 6 kg lithium as well as a liquid electrolyte. Besides, there are large amounts of plastic, aluminum, copper, and steel from housings, circuit boards, cables, and foils.
Battery-specific metals such as lithium, cobalt, and nickel are critical raw materials, which is why recycling is advantageous not only due to environmental protection but also to achieve higher availability security. If you are interested in the topic of critical raw materials, here is my post about it: http://greaterideas.blog/2021/02/21/from-energy-crisis-to-raw-material-crisis/
The problem of different batteries
There are many different types of batteries on the market. Their structure and the quantities of raw materials they contain vary depending on the manufacturer and are often not transparent. This prevents standardization and automation of the recycling process and makes the recycling of EV batteries expensive and time-consuming.
The recycling process
The most widespread methods for recycling batteries from EVs are thermal melting or mechanical crushing with chemical dissolution and separation of the valuable components.
Recycling with thermal melting
The battery cells are melted down. Due to the different melting points of the metals, they can easily be separated from each other. Most of the cobalt, nickel, and copper can be recovered in this way. In a further step, lithium is extracted from the slag. A disadvantage of this process is the high energy consumption. Also, graphite, aluminum, and electrolyte are not recovered with this method.
Recycling with mechanical crushing
The mechanical crushing is done by a shredder. This takes place in a room sealed off from the ambient air that is filled with protective gas (most often N2) to prevent the material from igniting.
Through various sorting processes, the different value components are separated and can be almost completely recovered. Aluminum and copper are obtained in their pure form. Most of the manganese, nickel, graphite, cobalt, and lithium are also recovered. Even the electrolyte can be collected. That means a recycling rate of around 96%. Compared to the new production of these raw materials, over 35% of energy is saved.
The future outlook
Several e-car manufacturers are currently working on a closed life cycle for EV batteries. Cooperation with battery manufacturers and recycling companies as well as an agreement on uniform standards are essential for the future. Recycling is essential for a sustainable future and stable raw material availability.