There’s always a great deal of debate around the Toyota Prius’ composition and just how hard it is to recycle the vehicle once it reaches the end of its useful life.
But the truth is Toyota had plans in place long before the car even reached the showroom to ensure it can be disposed of in an environmentally responsible fashion.
At the end of its lifespan more than 85 per cent of new Prius can be recycled and more than 95 per cent of its materials recovered in a process that only accounts for a tiny proportion (approximately two per cent) of its full life-cycle CO2 emissions.
Of special interest are the Prius’ high voltage nickel-metalhydride batteries which, thanks to a new recycling process, can now have up to 95 per cent of their components recovered for re-use with next to no emissions.
Batteries are removed at an authorised Toyota Prius Service Centre where an appointed waste management company arranges collection and transportation of these batteries to one of three European Final Treatment Companies.
The recovery process begins with the removal of the battery’s outer casing, which itself can be re-used in steel making processes. All the wires and electronic parts are sent to a specialist recovery company, while the power cells themselves are recycled using an induction-based vacuum thermal system.
This is an evolution of the traditional waste heat treatment process, but it consumes less energy, is almost emissions-free and is highly secure.
The cells are put into a sealed container from which all air is removed, significantly reducing internal pressure. The container is then heated to 800°C. When the temperature reaches 400°C all organic materials break down into a mixture of oil and water, which is sent on to a licensed water treatment company for processing. The power cells are then exposed to hydrogen, which helps break the oxides down into metals.
What is left after the process is a highly concentrated nickel alloy which can be re-used as a raw material in the production of new batteries. All the other metallic elements recovered can be used in the manufacture of stainless or other specialist steels.
For our first look at the 2010 Toyota Prius, click here.