Paul Christensen, Chair of Pure and Applied Electrochemistry at Newcastle University, and Director of Lithiumionsafety Ltd, discusses the potential challenges vehicle recyclers could face when handling lithium-ion batteries from electric vehicles.
By 2040 there could be an estimated 100 million (M) electric vehicles (EVs) globally and 1M – 25M battery packs from scrapped EVs. There could be up to 105,000 EV packs in the UK alone by 2025. However, at present, there is only a nascent lithium-ion battery (LiB) recycling industry in the UK and Europe, but it is clear that the industry has a crucial role to play if the “electric revolution” is to assist in the decarbonisation of the planet.
Unfortunately, there are almost daily reports of fires in bin lorries and recycling facilities caused by LiBs, and these are costing the UK economy at least £160M per year1. The situation is far worse in the USA, not just in terms of financial loss but also in terms of injuries and even deaths2. In addition, Materials Recovery Facilities in the USA are increasingly reticent about admitting to lithium-ion battery-related fires due to insurance concerns.
These fires are currently caused by small LiBs from or in e.g. mobile phones, laptops and even sex toys(!). Given the number, variety and size of the LiBs that recycling facilities will have to deal with in the future (not least EV battery packs in end-of-life EVs, and packs that have been used in “2nd life applications”3, e.g. battery energy storage systems), it may be that the global drive to replace fossil fuels could mean that the fiery epidemic in recycling facilities is actually the calm before the storm.
LiBs are amazing devices, able to store very large amounts of energy (in “kilowatt hours” or kWh: a 2022 Nissan Leaf has a 40kWh pack and a Tesla 100 kWh, HGVs up to 1000 kWh), but this is a double-edged sword: if this energy is released in an uncontrolled fashion (“thermal runaway”) through abuse, toxic, flammable and potentially explosive gases are released as well as fine particles of heavy metals. Abuse includes crushing and penetration, common outcomes in recycling facilities. The gases include carbon monoxide, ethane and other small organic molecules, hydrogen fluoride, hydrogen cyanide, hydrochloric acid, up to 50% hydrogen and droplets of the condensed solvents used in LiBs, giving them the appearance of a dense white cloud. Immediate ignition of the vapour cloud results in fire, with flares that can be several meters long from, e.g. EV batteries, whilst delayed ignition can (and has) resulted in vapour cloud explosions. From the academic literature, between 300 and 6000 L of vapour is produced per kWh: this means even small LiBs (e.g. eScooter batteries) can cause vapour cloud explosions.
So, be prepared for major challenges… as a simple example, the days of storing vehicles, especially road traffic collision (RTC) vehicles, in vertical piles and moving such vehicles with gay abandon are coming to an end. Moving EVs with, e.g. forklift trucks will have to be conducted with due regard to avoid abusing the battery packs, and storage will have to take into account the fact that EVs have reignited hours, days or even weeks after the initial incident and have done so several times. Thus, it is generally accepted that RTC EVs should be stored with a 10 – 20 m exclusion zone. With respect to operatives working on scrapped and RTC EVs, at least one Police force has amended the operational procedure for its forensic officers such that two (instead of one) officers work on an RTC EV: one actually conducts the investigation whilst one is on the alert for thermal runaway.
Finally, a plea. The understanding of the risks and hazards of lithium-ion batteries is, as far as I can see, very limited in the UK government: amongst the public, it is nil. From Amazon, it is clear that a number of UK companies are selling EV battery packs, and even damaged EV packs, to the public: whilst not currently illegal at present, it is irresponsible in the extreme. Please stop. When fully charged, EV batteries are up to 800V DC and cannot be switched off with the attendant risks of electrocution and arc flash explosion. In addition, whilst it is believed that normal use, e.g. within the specified limits of temperature and charge, does not have an effect on battery stability, it is clear from the academic literature that rapid charging of EV batteries destabilises them and can reduce the onset of thermal runaway down to room temperature. And, of course, damaged EV batteries could “rapidly disassemble” (in the parlance of the Carriage of Dangerous Goods Regulations, i.e. explode) or ignite, and so cause injury or death: in which case, where would the liability lie?
1https://www.eunomia.co.uk/reports-tools/cutting-lithium-ion-battery-fires-in-the-waste-industry/
3EV packs are judged to have reached the end of their life in the vehicle when they have irreversibly lost 20% of their charge when new, but they still have very significant value, and a major 2nd life industry is perceived to be in portable battery energy storage systems (BESS, e.g. building industry) and grid-scale BESS.
To contact Paul, please email him at paul.christensen@newcastle.ac.uk
