Depolluting and dismantling traditional Internal Combustion Engine (ICE) vehicles already presents a multitude of hazards. Petrol, Diesel, chemicals, lubricants, oils, dusts, carcinogens, acids, alkalis, sources of ignition, pyrotechnic devices, explosive atmospheres, confined space working, hot work, environmental contamination etc. Incorporating electric vehicles (EVs) into an already hazardous work activity presents the industry with its biggest challenge to date.
With 38.3 million cars and vans on UK roads of which only a small proportion are battery electric (<900,000), we are still years away from the seesaw tipping in the favour of EVs. The reality is that, just like they do on our roads, these technologies will need to be able to coexist, meaning longstanding dismantling procedures will inevitably have to be adapted to accommodate both.
The considerations highlighted in this article are by no means exhaustive, but they may provide a useful starting point for any feasibility study into incorporating electric vehicles into a typical dismantling operation.
Hybrids are likely to present the first large-scale challenge for the recycling industry. Their growth in the UK since 2018 has been strong and is set to continue as a stopgap for many consumers who are yet to make the jump to full battery electric.
Whether hybrid or full battery EV, it’s all high voltage (HV) and lethal if handled incorrectly, with the potential to compound the hazards already presented by traditional ICE vehicle depollution. It’s for that reason that HV awareness training should be provided for all, not just the technicians. Batteries store energy, not produce it, meaning that the vehicle’s HV system retains these lethal voltages even when a vehicle is switched off. There are well-publicised fire risks; the potential for explosive, toxic gases and harmful liquids being released into the atmosphere, if the HV system is compromised. Less obvious hazards include the silent operation of the electric motors, and the large magnetic forces generated, affecting both pacemakers and machinery.
Ensuring that Hybrid / Electric vehicles (H/EVs) are safely isolated is paramount and should take priority when a vehicle arrives on site, a minimum distance away from where other depollution is performed.
Fire Prevention Planning, risk assessments, environmental aspects and impacts register, will all need to be reviewed. It may also be necessary to consult with your local environment agency to ensure you are continuing to be fully compliant with the requirements of your permit.
Vehicle Research
It is imperative that the vehicle-specific information accessed is accurate and thoroughly researched for any H/EV vehicle, in advance of handling it.
If providing recovery services drivers will require their own occupation specific H/EV safety training, insulated PPE and Specialist tooling. They are likely to be the first employees to have to safely manage the vehicle, with limited support, and in a potentially hazardous environment and must therefore be capable of managing the risk appropriately.
Always use the Emergency Response Guides and Manufacturer / Model specific data to know exactly what is being dealt with and what vehicle specific precautions are needed to work safely.
Performing Visual Checks
Vehicles must first be visually checked for signs of damage to the high voltage electrical components or cabling by a trained technician using specialist HV tooling and PPE.
HV batteries are often mounted in vulnerable areas of the vehicle and are particularly susceptible to damage in road traffic collisions. If the integrity of the battery is likely to have been compromised, heat signatures will need to be monitored from the battery using infrared equipment. Any shorting or loss of electrolyte may present ignition sources in the event of fuel spillage.
Things to ask include: have the fire services made the vehicle safe? Was an extraction performed, and if so, has this compromised the structure of the vehicle? Has the vehicle been submerged in water, as this significantly increases the risk of electric shock.
Transporting H/EV Vehicles
Transporting a damaged H/EV with a hazardous energy source or self-ignitable components carries risk. The vehicle should be wrapped in a high voltage safety blanket during transportation. Towing should always be avoided unless it is safe to do so, as dangerous voltages can be generated by movement of the drive wheels. Once the vehicle arrives on site, it must be immediately quarantined for 48 hours to reduce the risk of fire.
Moving and transporting an H/EV needs careful consideration. The HV system, especially the battery, contributes to the overall weight of a vehicle, meaning H/EVs can weigh significantly more than their internal combustion counterparts, and available equipment must be able to safely manage this weight.
It is common practice to move ELVs around the work area straddled across the forks of a lift truck. Most Battery EVs are designed with the battery under the vehicle, taking up most of the undercarriage and making these lifting techniques impossible. Never support the weight of an EV by using the battery itself to support the vehicle as damage or short circuits could be caused, running the risk of fire, explosion and electrocution.
Damaged or Suspected Damaged HV vehicles
Any outside quarantine area for suspected damaged H/EVs where the vehicle can be monitored for up to 48 hours before any dismantling, needs to be a distance away from other ATF operations.
Treatment facilities will have to consider construction of a bespoke outdoor H/EV quarantine area using non-combustible interlocking concrete blocks with hard standing. Infrared technology will need to be adopted to monitor HV battery temperature for abnormalities
Shutting down the HV system
It’s not only the battery that stores voltage, so when preparing to disassemble, the power stored in HV components such as the invertor must be discharged (drained) for a qualified technician to safely work on the vehicle.
Manufacturers adopt one of two ways to discharge power stored in the invertor; active or passive. Active discharge dissipates voltage automatically when the ignition is turned off, draining in a matter of a few seconds. Passive discharge only occurs when the power is shut off to the invertor, meaning technicians must reference the vehicle specific information for disconnection to verify the required discharge time.
Lifting an HV vehicle
The battery packs on H/EVs are large and heavy. As a result, the recommended lifting points are often on the far edges of the vehicle frame. Traditional depollution lifts typically cannot accommodate these vehicles. A vehicle lift will be needed that has sufficient rated capacity and the capability to engage with the lifting points. Then, to safely remove a high-voltage battery pack from the vehicle, an independent lifting table is required.
Storing batteries
Storing a removed Lithium-ion battery presents challenges of its own. They must not be exposed to direct sunlight or other heat and ignition sources and must be kept well ventilated.
Most EV batteries from full battery electric vehicles require a large means of containment. Lithium-ion battery fires spread quickly and are notoriously difficult to control, and the bigger the battery, the bigger the blaze. With the limited availability of facilities for recycling these units currently in the UK, it’s likely that these batteries may spend considerable time at an ATF before being shipped off for processing, so adequate storage and monitoring is essential.
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