Thursday, 17 March 2016

Safe handling of electric and hybrid vehicles

13 members and guests attended, Chris Davis, Bruce Taylor, Jon Lowe, Steve Perkins, Steve Helps, Adrian Hicks, Mike Norwood, Steve Farr, Mark Eldown, Mike Berney, Aidan Earl, Gary Hunt and myself, braved the holdups on the M25 on this evening to attend the Borehamwood lecture.

Andy Latham from Salvagewire gave an excellent presentation on the advertised subject of Safe handling of hybrid and electric vehicle.

Andy starting the evening by giving his experience within the motor industry, starting as an apprentice in the motor trade, progressing onto an Engineer Assessor for Aviva for several years, which involved dealing with the blue circle salvage organization.

Andy used a clear, constructed PowerPoint and physical examples to get over the information, which was a shortened version of his training session.

Beginning with the basic five types of electric and hybrid vehicles, Full Electric, Parallel Hybrid, Series Hybrid, Plug-in Hybrid and range Extender. Andy gave a good explanation of these types and what actually classes as a hybrid, vehicles incorporating two or more power sources. These vehicles commonly referred to as HEV'S, giving an example of the BMW i3 & Vauxhall Ampera. Both of these cars only use electric to drive the driven wheels, but also have a small combustion engine as a range extender, which generates electricity to supply the battery, and in turn the electric motor.

Worldwide it is estimated that 40% of vehicles by 2020 will have some form of electric propulsion

Andy explained one hybrid design involving a regenerative braking system which could be adjusted to suit your own preference and driving style, acting as a braking mechanism and storing the energy. This system uses a small weighted flywheel in a vacuum designed casing, which in braking causes the flywheel to spin at high speed and this energy is then used to aid the vehicle from stationary starts and low speed driving.

Andy went through the procedures to shut down electric vehicles, starting from the Personal Protection Equipment, to the 1000 volt rated volt meter required. The vehicles currently use between 400 & 800 volts. To ensure the system is safe to work on, it is essential that volt readings are taken to confirm the system has been correctly made safe. Andy stressed the importance of always following the manufactures procedures, this usually involves allowing 10 minutes to pass once the correct stages have been completed, so that the capacitor can discharge.

There is no consistency across the manufactures for shut down procedures. It varies from between manufacturers, with some vehicles requiring 16 steps before the vehicle is made safe, finishing with a padlock to prevent the system from being accidently reconnected such as in Mercedes. Toyota are far more straightforward with only four steps.

Andy emphasised the importance of being aware of the possibility of leakage from the NiMH batteries, stressing the need for testing of any suspicious liquid with litmus paper, neutralizing any positive readings for acid with a Boric acid solution, retesting and applying Boric solution until the readings show that it is totally neutralized.

Ownership of the batteries was discussed, as some manufactures now retain the ownership and in turn the responsibility for disposal. This is a consideration when a total loss comes into play. The price of a battery for a Nissan Leaf is estimated to be £8500. Saying this, Toyota batteries have been very reliable with only .01% of the batteries failing to date. The batteries continue to develop with the capability of now replacing individual cells such as for the BMW i3, thus reducing the replacement costs of a failure occurs.

A big consideration when assessing vehicle damage on the electric and hybrid vehicles, is there the skilled personal to carry out the work on a specific make and model. Andy stated that one Mercedes hybrid was written off due to there being no one trained to work on such a vehicle. Breakdown drivers need to be trained in the safe recovery of these vehicles. They also need the ability to identify them when recovering from an RTA to ensure the vehicle is not moved in such a way as to start generating electricity.

The presentation ended with questions from the audience and a show of appreciation for such an informative presentation.

Peter Beddow