The Electric Car - Are There Better Ways Of Fueling It?
The electrical vehicle is not a new concept, but it has always suffered from the same Achilles heel: range. There are a number of possibilities being put forward as technology advances and the question is - which options, both current and in the future, offer the best answer for making electric transport a viable option for both domestic and commercial vehicles?
Lithium Ion batteries
As the most commonly used form of power source, Lithium Ion batteries are also the centre of current technological development. Li units are notoriously expensive to produce and here lies the main problem as it takes electrical vehicle ownership out of the range of many users. However, improved industrial processes are bringing the price down, but there still remains the issue of longevity. The warranty on current batteries is far less than that of the vehicle it is fitted to and their recharging cycle is limited by the tendency for them to erode internally, which also gives birth to safety issues in older units. Researchers at Stanford University have been experimenting with carbon nano technology that reduces effects of the lithium deposition allowing more recharging cycles. The result is longer and more efficient battery life.
The hydrogen Fuel Cell
Hydrogen is the most common element in the universe. Conversely it is arguably the most difficult to harness as it doesn't exist as a free gas because of its tendency to bond with other molecules. Consequently, it can be expensive to produce and with current power systems, fossil fuels are used to crack it and cool it. There is also the important element of safety as Hydrogen likes to escape from encasement and causes metal to become brittle. However, as a fuel cell concept, it is one of the cleanest and has the most potential range. The fuel cell works by passing H2 through a platinum catalyst producing a very small electric charge, hence the need for many stacks of hydrogen cells in one unit. The reaction produces electrical power plus heat and water making the process very clean.
Electricity producing tyres
Although very much in its infancy, Goodyear have released proof of concept material around tyres that can produce electricity to power a vehicle. They will work in a number of ways; firstly, by generating power from heat caused by friction as the vehicle drives along, secondly, by utilising tyre flex and finally, solar power from collecting heat on its thermo-piezoelectric layer during hot weather. There is little information regarding how the energy produced would be transferred to the vehicle batteries and it would arguably be an addition to a primary power unit.
Much of the current research centres around improving the existing technology and most of that is to make batteries more efficient. Electrical current is generated by moving electrons from an anode to a cathode and in current Lithium ion batteries, the process happens thousands of times within a battery unit, due to the constraints of anode/cathode technology. However new strides forward in manufacturing processes are using different materials and production techniques that allow for thicker anode/cathode arrays which are arranged differently. The current top end Lithium ion solutions give an energy density of roughly 250 Wh/Kg (Watt hours / Kilogram) but the new technology being developed and tested by 3M has given results of up to 300 Wh/Kg, with moves to achieve 500 Wh/kg. The batteries are lighter and use less components and metals, bringing both weight and price down dramatically.
Battery hot swap technology
Although feasible in theory, most electric vehicles companies have not taken up the concept of swapping out a used battery for a charged one, so cars are not designed with the facility in mind. The procedure used to 'hot swap' a battery is fundamentally sound, but it appears that the infrastructure required is not being considered.
As can be seen, much of the research currently underway is around making batteries smaller and more efficient, so charging becomes paramount. Currently, there are insufficient, easily accessible charging stations for an extensive roll out of pure electrical vehicles, although more are being built. Also, charging technology is constantly improving, with systems able to charge an average battery to 80% in thirty minutes. The fundamental problem with electric vehicles still applies; they need to be charged at regular intervals, so the main issue facing the EV user is where the vehicle can get a top up. In some countries, infrastructure is at an advanced stage of development and charging stations are being built as little at 30 miles (50 Km) apart, allowing for fast and easy charging and alleviating what is being termed 'range anxiety'.
To sum up
It can be argued that the safest and most convenient way to power an electrical vehicle at the moment is by a battery, hence the current concentration on new technology in the field. New charging systems and so called superchargers are the key to alleviating the issue of keeping an EV powered and mobile over an extended range. The building of an all encompassing charging network is arguably the only way that the evolution of EV's as a primary form of transport, will occur.