Why Chemistry Dictates An Electric Vehicle Future

In a world of declining fossil resources, the day of the petrol and diesel-powered automobile is limited. That's nearly a given. Eventually there won't be enough excess oil or gas resources that the world's population will want to "squander" on road transport. And though we might extend their lifetime by again turning to coal, of which there is now more under the ground than there is oil, the process of converting coal to petrochemical products for powering cars is prohibitively expensive.

It's now safe to say that future road transport will be powered by electricity. Is it too much of a bold statement to say that electric cars will be the only cars on the road? Anyway, before we reach that stage there will be hybrid cars, but that will only be an intermediate stage before all road transport is entirely electric. This is not crystal ball gazing; apparently it's an unavoidable fact which car manufacturers have hedged their bets on.

The current problems with electric cars relate to the current problems with smartphones. Whilst technology has advanced leaps and bounds in most areas, battery technology has been dragging its heels. The modern car is controlled by a sophisticated computer (the engine control unit or ECU) just like your iPhone, but what is not realised by many is that ECU technology is just as advanced as smartphone technology. The development of both of has been compliant with what is known as “Moore’s Law” so named after its discoverer (who was the founder of Intel).

Moore’s Law states that the complexity of electronic devices roughly doubles every 18 months. This means that computers run faster and can do many more things. It is the reason why smartphones are so much smarter year on year and the reason why modern petrol and diesel engines are so much more fuel economical than they were just a few years ago; it is electronics that have made them thus.

Unfortunately the tech behind battery technology is essentially chemistry, and chemistry is subject to a very different set of rules from those governing electronics. Ultimately electronics (or in its next guise which will be photonics) can operate at the speed of light, so there is ample space for advances in technology to move ever closer to the ultimate limit. However the processes that underpin chemistry involve mass transport, and it is impossible to move mass around at anywhere near those speeds. The technology is already pushing against the boundaries imparted by physical laws.

When batteries charge and discharge, physical processes are at work that involve the transport of ions (ions are atoms that have gained or lost electrons). Ion transport is a slow process; however there are ways to speed it up. New developments in nano-technology have allowed scientists to create lithium ion batteries that can be charged up at only a fraction of the time that it takes currently. So far a prototype of the equivalent of a smart phone battery can be recharged in under a minute, and batteries suitable for future generations of electric cars that can be recharged in just tens of minutes are being developed.

There are significant problems with these technologies that may take many years to overcome. But all the signs are pointing towards a world of electric vehicles. Would that be such a bad thing?