ISSUE 011 Autumn 2021 Candela C-7 hydrofoil speedboat dossier l In conversation: Robert Hoevers l Battery recycling focus l Vehicle dynamics insight l ZeroAvia hydrogen-electric aircraft digest l Motor materials

As a result, vehicle manufacturers are teaming up with recycling firms to optimise the design of cells and packs from their suppliers for their recycling partners. More than 1.3 Mt of battery cells are expected to be recycled each year by 2030, according to predictions of EV use and lifetimes, and this requires a considerable recycling infrastructure. This is up from just 100,000 t of batteries recycled in 2019, 70% of that in China. There are currently only a few large- scale industrial processes that can handle the growing amount of used lithium-ion batteries. Even the smaller pilot plants are still at the r&d stage and can’t process and purify all the different battery elements in an economical way. That means there is still a need for a process that can economically process all types of used lithium-ion batteries. The recycling process In the current recycling process, the first step is to discharge the pack completely, as there can still be significant amounts of charge inside. In the worst case, this can cause fires in recycling centres as the dismantling can cause short-circuits. This takes time and requires specialist equipment to ensure safe discharging. Discharging a pack quickly for recycling means there are potentially large currents flowing, so any dismantling equipment has to be carefully isolated. That has an impact on where the recycling is carried out. If, like Tesla, a car maker has control over the complete supply chain, then the pack recycling can be integrated into the production process and a specialist recycling plant with dedicated equipment can be built alongside the battery plant. However, the trend towards battery ‘gigafactories’ means this can be a challenge, as the packs might have to be transported hundreds or even thousands of miles back to the recycling plant. There are also significant restrictions for safety reasons on transporting lithium-ion battery cells, especially exhausted cells that may be in an unknown condition. All this means there is a demand for more local recycling plants, which requires more distributed specialist skills and equipment. Many recycling systems work at the cell level, so the discharged pack also has to be dismantled. Again this has to be done by hand and can be time-consuming, but it does allow the plastics and some copper wiring to be removed. The sensors and wiring used for the BMS can also be removed, if they haven’t already. However there is increasing interest in ‘all-in-one’ processes that can accept complete battery packs. Currently, battery recyclers focus on the mechanical and physical separation of the different components of the batteries, such as the casing, current collector and the electrode materials. These processes usually involve crushing the batteries in a controlled inert atmosphere, and the crushed material is then separated by sieving, come in many shapes and forms. This is made even worse with structural batteries that can be in the sides or roof panels of vehicles, making disassembly slow and costly. The start of the recycling process at a specialist recycling centre (Courtesy of Li-Cycle) Autumn 2021 | E-Mobility Engineering 33 Focus | Battery recycling