Wednesday, 23 November 2011

Electric cars need a lot better batteries

The electric car is on the car industry's agenda. Most car manufacturers tend to agree that, within three to five years, electric cars will have captured market share, or at least a niche; but most of them are still trying to find solutions to critical obstacles facing the electric car industry.

The problem is not in the car itself. Car manufacturers know how to produce comfortable and fast electric cars. Limited trip length is also not the main problem, since most manufacturers are targeting customers who intend to use the car for intra-city driving or the occasional inter-city drive. For these customers, being able to drive 150 km between charging stops, and even 250 km in the future, is certainly sufficient.
The real problem lies in two issues: battery cost, which is about £750; and recharging time. The high battery cost is a classic chicken and egg dilemma. In order for the price to drop significantly, the batteries need to be mass produced. But they cannot be mass produced until a large number of people purchase electric cars.
In order for the mainstream to overcome its natural reluctance to purchase an electric car and for it to become mass produced, the electric car needs to be available at a reasonable price, and be just as easy to use as a regular car - which is where the battery issue enters the picture. Fully charging the car battery at an ordinary house outlet takes between six and nine hours. That is an unreasonable amount of time required to recharge the battery for every 150-200 km. It forces the customer to adapt himself to the car and not the opposite. Three solutions have been offered to solve this problem:
1. The chargeable hybrid
This solution involves a small gasoline-powered auxiliary engine that can act as a generator so that the car can self-charge, or as an emergency backup in case the battery gets completely drained. This is an effective solution, but it is only an intermediate stage on the way to a fully electric car.
2. Changeable battery
This solution sidesteps the issue: instead of waiting an extended period of time to charge the battery, the battery is simply swapped out for another fully-charged battery. This solution is technologically applicable, with battery changing time similar to filling up a regular car with gas at a gas station.
This solution also enables the price of the battery to be separate from the price of the car, thereby bypassing the obstacle of the battery's high price, and exchanging it with the cost of long-term battery rental. Except that this solution has a few limitations that are currently holding back car manufacturers from adopting it. The main limitation is the high cost involved in planning which type of car to produce, or the conversion of existing cars to include the removable battery apparatus, as well as building the robotic stations for changing batteries, which is estimated at $1 million per station.
And lastly, the creating of a unified global standard for quick battery exchange is still a long way off, and until such a standard exists, each change station will be built to service a specific car model or make. In other words, there is a problem.
3. Quick charge
The third solution, which has had some breakthroughs in the last few months, is quick charge. This is the commercial charging of the battery using an industrial-strength battery, which shortens charging time to 30-40 minutes, and can be installed at gas stations or other points along the highway.
Four years ago, this technology had many limitations. It was very expensive, and the quick charging process damaged the batteries and drastically decreased their life span. But then the car industry reached a consensus regarding the quick charge issue. Seven large car manufacturers - Ford, General Motors, BMW, Mercedes, Porsche, and Volkswagen - agreed to a unified standard, which will lead to accelerated development.
Quick charge stations have another limitation, which will only exacerbate as more and more electric cars are deployed, and that is the traffic it creates on the electricity grid. Countries with sophisticated grids can handle this traffic, but electric companies in countries with outdated and limited electrical output, such as China, are hesitant to adopt this solution. For this reason, China is currently experiencing a struggle between the supporters of quick change batteries and the supporters of the battery exchange method.
By the time this struggle is settled in the West, there will already be hundreds of quick charging stations on a commercial or experimental level. In Israel, it appears, the solution to the charging problem has been decided from above by Shai Agassi's electric car venture Better Place.

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