The reality of lithium-ion batteries

This attachment to the environmental is an emotional one as much as anything and is not one affected by the hard facts of the various environmental impact analyses you must surely consider if you want to drive one of the new electric cars out of anything other than a dedication to the latest fashion.

It's not enough in the long term to market as car as green, to badge it as the 'Leaf' and furnish your website with the iconography of the new green movement. At some point you would hope people will start talking about the environmental values at stake here.

Indeed they are already on blogs and other green forums, scrutinizing the real environmental savings to be made (or not) if you switch to an electric vehicle.

With a brand new product there are inevitably going to be uncertainties as to long-term performance, or more specifically when talking about electric vehicles the main uncertainty is with regards to the impact of lithium-ion batteries on the environment. If the technology at the heart these new cars turns out to be environmentally damaging the credibility of the whole movement would be undermined.

A recent study by the Swiss Federal Laboratories for Materials Science and Technology (EMPA) breaks down the true environmental impact of li-ion batteries. They tell us:

'About 15% of an electric vehicles' total environmental burden comes from manufacturing, maintaining, and disposing of the lithium-ion battery. Most of those costs, about 50%, stem from mining and manufacturing the copper and aluminium used in the battery and its connecting cables. Extracting the necessary lithium produces only 2.3% of the battery's total environmental footprint.'

Meanwhile the whole business of charging your car and the environmental impact of this is surrounded by uncertainty. Even the lay reader will recognise that the electricity you put into this zero-emissions vehicle has to come from somewhere, and more stats from the people at EMPA will tend to confirm the obvious.

If you refuel using electricity from coal-fired plants your EV's environmental impact goes up by 13%; if you can possibly charge solely from hydro-powered sources your car becomes 40% more environmentally friendly.

The analysts at autobloggreen highlight the key finding of the report. That in order to achieve parity with EVs in terms of the environmental impact, a car with a standard internal combustion engine would have to do between 60 and 80 mpg.

Which is surely now the target to aim at. These figures reveal how relative any environmental gain is going to be in the short/medium term at least, with the comparisons to our current crop of road vehicles revealing of exactly how far we have to go to achieve truly clean transport.