The problem with battery technology is simply getting enough raw energy into the batteries fast enough during a “recharge” Those folks who insist that you can recharge an electric car battery in 5 minutes for a vehicle that will travel 500 miles and haul a mother, father, 3 kids, a dog, and a bunch of groceries simply don’t understand how much energy is required to make that happen.

One “cool” thing about hydrogen vehicles is that they can do exactly that: “recharge” quickly and on demand using equipment very similar to a gasoline pump and storage tanks. To “recharge” an electric automobile in a similar fashion, you would need direct access to a 10k volt electric grid substation and arcing such huge amperage into your vehicle that you wouldn’t even want to be in the vehicle when it was recharging. Yes, recharging on the order of a couple hours or more can be done with conventional 110/220 volt power circuits, but it isn’t trivial and takes a drastic change in lifestyle that many people don’t want to make.

BTW, Li-ion batteries, while in theory might be able to get to energy densities of gasoline, certainly aren’t there yet or even close. It is about 1% the energy density… and that is a pretty good accomplishment for batteries.

While battery technology has been showing a curve of improvement similar to Moore’s law, the “half life” to when improvement is seen to double the capacity is measured in decades, not months. Keep in mind, electric vehicles pre-dated the introduction of wide-spread internal combustion engines and were some of the first kind of mass-produced automobiles ever made. That’s 19th Century tech here!

As for the energy cost of producing a “gallon” of hydrogen fuel, before anybody goes off and complains about its cost, compare it to producing gasoline…. you’ll find that producing a gallon of gasoline consumes far more electricity AT THE REFINERY than it releases in terms of usable energy in an automobile.

httpv://www.youtube.com/watch?v=8DBf8GBVmME

Even though it seems to be a good safety feature, there could be many potential long-term threats.

1. Increase Cognitive load: now there is one more feature to think about before you ignite your car.
2. Dependency: This is the first step where computer is taking over the driving seat what if the driver is use to this feature and one day, for some reason its raining or the windshield is not clean
3. Distraction: Think about a scenario where you are driving down a street and suddenly you experience sudden break. Well, you have just avoided an accident. However the car only stays still for just more than a second. Is that enough for you to react?
4. Identification: car cannot identify humans or animals. That said, it would stop for other cars but would not care about dogs and little children.

I believe it’s a good first step however the technology is still very new. Instead of doing a field test in the real world, may be it should try to solve potential big questions.

The last thing we want is another accident because of this new “city safety” feature.