Was looking at the design of the “fuel gauge” of the Nissan Leaf, where an electronic bar gauge shows the state of your charge. This had my obsessive compulsive side kicking in with the thought that this line of thinking looks out of date and should be upgraded already for this mode of technology.
In the age of fossil fuels, graph or lever gauges are ideal because it gave car designers a simple way of telling you how much fuel you had left in your fuel tank. Fuel, in liquid form, sloshes around your tank, so therefore the trusty fuel gauge is just a snap shot of the amount of fuel in your tank and not really an accurate value for the amount of fuel in your tank. In most fuel gauges, it gives you a linear display of the fuel being slowly consumed so as a driver you know when to drive your car to the station to have it refuelled.
For electric vehicles however, what you have is a state of charge. Where in once the electricity in your battery is drained, there goes your power to run the vehicle. Since it is also electrical in nature, we can be more accurate in predicting the time where the electricity will be gone from your battery pack.
With that, I can’t help but think that the best way to tell a driver the state of charge in his car is if we go from the previous gauge system, to this:
A count down timer based on the amount of charge being drawn from the battery or its current state of charge would be the best way for me to tell the driver how much time he has before he drains his battery. The amount of drain an electric vehicle imposes on its battery is greatly affected also by the amount of appliances he has running (airconditioning, radio, etc), so a driver can easily be informed by the amount of time he has left to run the car depending on the amount of appliances he has running as well as his driving style. With this information, he can also accordingly adjust the latter in order to preserve his charge (turn off airconditioning, radio, etc)
Not that I’m saying that we do away with the old gauge system. But together with the timer system, it would be the best way of passing information on as to the state of charge of an electric vehicle.Category: Automotive, Electric Car