Battery packs for vehicles will not be the answer

James Robertson points to a very interesting detail related to electro-mobility that I haven’t thought of before:

… it can take as long as 20 hours to charge up the car using a standard 120-volt circuit. If you hook up to a 240-volt Level 2 charging station — which can be installed in your home for the estimated cost of $2,200 — you can cut that time down to eight hours or so for a full charge.

So living in the states where the outlets have 120 Volts rather than 220-240 means charging you car takes double the time or you have to invest a siginifcant amount of money just for reducing charging times.

This will of course put high obstacles into the way of electric mobiliy in one of the biggest market for cars – one that I’ve never thought of before.

But, to be honest, I am quite convinced that the whole battery pack idea is wrong, both from a practical and ecological / economical standpoint. As long as the electricity for our cars comes from nuclear or coal plants, and as long as we have highly-toxic battery packs in our vehicles, there is not very much ecological sense in all this.

If it takes many hours to charge a car, it’s impractical or inconvenient for many people. That’s not the way to convince the masses of a new technology.

I also see issues with replaceable battery packs. Sounds expensive, time consuming and also incenvenient to me, not to speak of the problem of how many stations I will be able to find where they can replace my battery pack.

There is an interesting sounding alternative to battery packs: it is called flow batteries or Redox-Flow-Batteries. The idea is that there is an electrolyte that flows through a power genarator. The base principle is easy: you have two fuel tanks in your car: one for the loaded electrolyte and one for the used, “empty” electrolyte.

Why do I think that sounds better than battery packs?

First of all, recharging your car means removing the used electrolyte and refilling the tank for new electrolyte. So the charging of the electrolyte happens outside of the car, at any time or place. Even if tanking/untanking would take 3 or 5 minutes, it would be very similar to how we tank our cars today. And it still would be cheaper and faster than most battery pack replacement concepts around. Sounds very nice to me, I guess this could be adopted by the masses pretty easily.

So uncoupling the charging process from the car brings many advantages:

  • No need for an outlet at my parking spot
  • Unlimited mileage by tanking new electrolyte, just like fuel today
  • Reuse of existing distribution channels, like gas stations
  • No hassles with broken batteries. If the electrylote is “empty”, tank new
  • Better chance for ecologically friendly power production

Let’s assume we want electric cars because we want to do something good for the environment (I know, that’s naive, we want them because electricity promises to be cheaper, but….). What could this technology do for us?

The electrolyte would be charged at the gas station or even better in big plants. Imagine somebody setting up a huge solar plant in some sunny region, like some desert and using existing infrastructure like ships and tank lorries to transport electrolyte instead of oil. Or water power plants, or whatever ecologically sensible way of producing electricity we might think of. We could ship the loaded electrolyte around, just like we do with oil today. And we could do it by using flow batteries in the lorries or tankers (not sure if that’s practical).

If we wanted, this could be good in many ways:

  • We could help poor but sunny countries to make money by delivering our electricity
  • The today rich oil producing and sunny countries could invest in such solar plants to earn lots of money even if they run out of oil
  • The petrol companies could provide their infrastructure (tankers, lorries, gas stations, ports etc.) to distribute electrolyte instead of gas
  • We would not have to build up extremely expensive power networks to transport the electricity
  • We could use solar energy for our cars rather than conventionally produced electricity (which is just making the pollution invisible for the individual driver but solves no problems as long it is not produced in an ecologically friendly way)
  • We could probably really do something to reduce CO2 emissions

So in all, I wonder why no big player tries to invest in this technology for electric vehicles rather than expensive and fragile battery packs.

There are, however, first attempts at using  redox-flow batteries for cars (article in German), but only financed very poorly.

Interestingly, the approach by the Fraunhofer institute seems to promise that you can reach up to 100 km with one tank – theoretically. I guess with a few million bucks in Research, there will be more progress.


5 thoughts on “Battery packs for vehicles will not be the answer

    1. Carl,

      yeah, maybe we’ll have a cold fusion reactor in the glove box in a few years.
      At least that could solve James’ problems with the A/C 😉
      But the ratio between science and fiction in your proposal is clearly a bit different from the one in mine. The flow battery exists and is in practical use, but not yet on vehicles. As far as I know, fusion reactors are not to be expected any time soon…

        1. Carl,

          well, I watched it and I got the impression that there’s some progress in the field of cold fusion technology. To my understanding, we now know it’s feasible. But to my (very, very limited) knowledge, we’re quite far from seeing it in daily use. But I may be wrong.
          I am a bit sceptical though. Back in the fifties and sixties, people thought nuclear energy will be THE solution to all energy problems, and nobody was worried about possible problems with (or caused by) it…

          But, hey, if cold fusion works harmlessly, and if it can replace batteries, or if it can be used to charge batteries *ecologically* (I now too little about cold fusion to judge this) and cheap, why not?

          Maybe what I want to say is that I think the research part for flow batteries is (mostly) done, and now it’s time for development/engineering in order to use it in verhicles, while my understanding is that there’s still a lot of research to do on alternative technologies like cold fusion.

          If we see electric cars as the future in 10 or 15 years, we are mostly worried about the right way to store electricity in a car, and not so much about how to produce it. There are well-understood ways of producing electricity today, some of them promise to be ecologically sensible while also affordable (solar, (geo-)thermic, organic gas, water power etc.), and if cold fusion can jump into the ring and join these, fine. Still we need ways to store electricity on a vehicle as long as it cannot be produced there in a sensible way.

          1. The geothermal route seems very practical too and it’s not a new technology. You don’t even need to be near a volcanic source to leverage the temperature difference between what’s under ground and what’s above ground.

            I am a pusher of cold fusion awareness because if you mention it to most people they still think it’s crackpot science. I agree that it is in its infancy as a field, but it is a world shaking paradigm shift in so many ways. With all the promises we get from government about funding green energy I think it’s a crime that this isn’t all over the news and that more money isn’t being pumped into developing the technology because better results have come from a tabletop experiment than from giant reactors.

            If Obama wants to restore his popularity, he could do worse than to champion the accomplishments of his country’s own US Navy Laboratories in providing reproducible cold fusion. It’s an exciting and positive prospect and it would make a refreshing change from all the ecological gloom and doom.

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