Having owned an electric vehicle for just over 18 months now, I feel able to share my knowledge, which may be of help to those considering an electric vehicle for the first time, or those who have just started out on the road to electric vehicle driving.
One of the most talked about topics is range anxiety, and I can honestly say that range anxiety is very quickly replaced by range awareness, after a very short period of driving an electric vehicle. Range anxiety is where one is constantly worried about whether the car will reach its final destination, or the next charging stop, before running out of battery power. This is just due to inexperience.
Range awareness, on the other hand, is where you know precisely how far your car will go on any percentage of the full charge, so that although you are very aware of the range issue, you are always confident about reaching your planned destinations.
Before setting out on any journey where the distance, there and back, is more than the available range for my car, I carefully check the route, check the availability of fast chargers on the route, and plan my journey in precise stages between the charging stations. The only time I do feel the slightest anxiety now is on arriving at a planned charging stop with only 10% of the battery left and thinking how all my best laid plans will lie in ruins if the charger is out of order or in any other way unavailable. So far, I am glad to say, that although I have had a few problems with chargers, I have always either been able to sort them out or find an alternative, and 99% of the time, I have had no trouble with chargers at all.
What Influences Driving Range?
Now that we’re talking about range, a topic that follows on naturally is how to get the best range out of your electric vehicle and what might have an adverse effect on range. One issue, which people need to be aware of but have no real control over, is temperature. The battery works by a process of chemistry to store, and yield, electricity, and chemical reactions work more efficiently at higher temperatures. This is because temperature is a measure of the excitation of molecules, and molecules that are moving about a lot — just like people at a party — will interact with each other more frequently than if they’re all sitting still.
In the UK, where I live, we do not have great extremes of temperature, so seasons really have very little effect, but where temperatures are dropping down to -20°C, batteries are badly affected. Electric motors, on the other hand, work more efficiently in the cold, and in any event, electric vehicles do have systems to regulate the temperature of both batteries and motors, but even so, expect range to be affected in very cold temperatures, and to improve when it’s warm.
Another item affecting range is rolling resistance. When a wheel is rolling, the weight of the vehicle is compressing the rubber in the part of the tyre that is in contact with the road. This causes a constant flexing of the tyre rubber, as each part of the circumference of the tyre is compressed when in contact with the road and then released while in contact only with air.
This constant flexing causes heat in the tyre, so that a certain amount of the energy of the car moving forward is converted to this heat, and also lost in the mechanical resistance to movement of the tyre rubber in flexion. Your electric vehicle should be fitted with low-rolling-resistance tyres, which flex less than normal tyres and are inflated to a higher pressure. You can squeeze just a little bit better range out of your car by ensuring that the tyre pressure is always as it should be.