The story so far - 100 years and not much evolution?
Anyone who has followed the history of electric vehicles can argue with some justification that not much has happened in terms of EV performance in the last century. The 100 year-old Baker Electric, the first "proper" EV by many accounts, had a top speed of 14 mph and a range of about 50 miles. While the top speed has improved in today's electric vehicles, the range of many EVs on offer today is still not much above that of the Baker Electric.
The reason for this lack in evolution is that most EVs still rely on Lead-Acid batteries for energy storage. These are inexpensive and reliable, since they have been around for, well, 100 years and more. However, they have a relatively low energy density, and the performance decreases rapidly over time.
2007/8 - finally the breakthrough?
It is clear that battery technology is the key ingredient when it comes to the performance parameters of any EV. In recent years, a growing number of researchers and companies have been working on improvements on this front. This is now reaching the market with large-scale Li-Ion based batteries (the type used in most electronic devices today). We will also soon see EVs that use batteries enhanced by nanotechnology*. The combination of Li-Ion and nanotechnology provides significantly enhanced storage capabilities and lifetime of the batteries, with virtually no deterioration of performance even after several hundreds of charging cycles.
This means that for the first time, high performance EVs will be available for purchase in several categories. Examples include the Tesla Roadster sports car and the Phoenix SUV.
With significantly extended ranges of 200 miles and more in the case of the Tesla, and top speeds above 100 mph, these vehicles come close to their ICE (internal combustion engine) powered competitors. In terms of acceleration, they beat most of them hands down. As for environmental friendliness, they are still at least 70% less polluting than the most efficient ICE powered car.
"Detroit" (and companions) are moving, too
In parallel, the huge market success of Hybrids, especially in the US, has led the major vehicle manufacturers to work furiously on the logical next step of the hybrid concept, namely Plug-In Hybrid Electric Vehicles (PHEVs). These contain larger battery packs that can be charged directly at any domestic power outlet (literally plugging the car in), and which provide all-electric driving ranges of several tens of miles.
In some cases we will see these vehicles offered in a "serial" rather than a "parallel" hybrid configuration. "Serial" means that the combustion engine is used exclusively to charge the batteries, rather than driving the vehicle directly. This allows a more efficient usage of the petrol that powers the engine (since it can be operated at its most energy efficient level).
We will see PHEVs coming to the market in 2009, and first large-scale serial configurations can be expected in 2010. From there, the way is clear: PHEVs will feature ever more powerful battery packs, offering ever higher ranges and performances. It is likely that beyond 2010 vehicle manufacturers will offer most of their models in a hybrid version.
Long term outlook
In the long term, i.e. beyond 2020, we don't expect the traditional internal combustion engine to play a major role in vehicles anymore **. Fully battery electric vehicles will be able to provide performances similar to today's petrol powered vehicles, yet with all the green credentials only EVs offer.
Speaking of long term scenarios: We have seen a lot of talk about the so-called "hydrogen economy" in recent years. When it comes to personal transport, this means vehicles with fuel cells powered by hydrogen. These hydrogen-powered vehicles have many disadvantages however. While they don't produce any exhaust gases at tailpipe level, a lot of energy and emissions go into the production and storage of hydrogen, so from an overall point of view we do not gain much over today's fuels.
If, however, battery technology continues to be developed at the current pace, and prices decrease as expected due to mass production, then it is not unlikely that we can skip the "hydrogen economy" altogether. Battery-electric vehicles are much greener than hydrogen powered ones already with today's energy mix (i.e., mostly coal fired plants). And as we gradually move to more renewable sources for power generation, this will further improve the environmental impact of EVs.
The future is electric, battery-electric!
*: The "trick" is to enhance the electrode material of the battery in such a way that the electrode cannot react with the electrolyte. In traditional batteries, this reaction over time creates a barrier (the so-called Solid Electrolyte Interphase or SEI), which gradually decreases the flow of ions to the electrode. This reduced flow has a negative impact on battery capacity over time. which anyone who has used a laptop or a mobile phone for more than two years can easily confirm.
**: A viable green alternative may however be provided by vehicles running on bioethanol. That is, if the process of producing ethanol from low impact biomass such as switchgrass and woodchips can be developed in a large scale and efficient way. This will be mostly CO2 neutral, but still doesn't get rid of the noxious exhaust gases at tailpipe level and the inherent inefficiencies in internal combustion engines. More on this in the alternative fuels section.