This is an idea that I have been playing around with in my head for a while, and it came back to me while I was making an annotation for an electric car post. The idea is simple:

A couple of foreseeable problems with electric cars in the future are:

1. The recycling and disposing of toxic batteries makes (as Braubeaton pointed out in the electric car anno) for an environmental problem from a seemingly green solution to an environmental problem (toxic waste from electric cars that replace gasoline enegines). With me so far?.

2. Recharging the batteries (The convenience of gas stations is hard to compete with). I don’t want the hassle of driving my shiny new Tesla Roadster 200 miles and waiting hours before I can drive it again.

So here’s my idea:

Vanadium battery technology is relatively new (at least to me). From what I understand, it uses vanadium dioxide as an electrolyte that can be reused infinitely by recharging. The batteries can be recharged by draining and replacing the electrolyte.

So what if you had ‘gas’ stations for electric cards where when you needed a recharge you drove in, and an attendant would (or yourself for the self-service stations) drain the vanadium from your battery and replace it with charged electrolyte. Since your replacing the electrolyte (as opposed to throwing it away), its better for the environment, and all you would be paying for is the charging of the electrolyte.

Like I mentioned, I am no battery expert, and there’s probably some obvious drawbacks (the one that I came up with was that vanadium has a low volume – power ratio, but there must be a way to get beyond that) to this, but I think it’s a nice pie-in-the-sky idea.
-- energy guy, Jan 08 2007

Information on Vanadium Batteries http://www.treehugg...the_vanadium_ba.php
Theres more out there - just google it [energy guy, Jan 08 2007]

More Vanadium Fun Facts http://www.vrb.unsw.edu.au/
From the University of New South Wales [energy guy, Jan 08 2007]

Using a V-battery in cars (site has terrible background) http://www.geocitie.../3589/vanadium.html
This idea is at least ten years old: "Dr Jacques explained that when a vanadium battery runs down, the owner merely has to drain the discharged liquid and refill the tank." [ldischler, Jan 08 2007]

Pumps http://en.wikipedia...:Adult_plimsoll.jpg
Vanadium pumps would look like this, only silvery grey. [spidermother, Feb 04 2011]

Could you please post some more info about these batteries, and how they work? Wouldn't replacing the electrolyte eventually erode the electrodes? It sounds like a good idea, besides the drawbacks you mentioned.

I've heard that you can do this type of thing in lead acid batteries by replacing the acid, but I'm not sure how this works.
-- discontinuuity, Jan 08 2007


Why not hot swap the whole battery array at once? Quick, no spills, no fuss...
-- GutPunchLullabies, Jan 08 2007


You recharge it and its ready to pump back into someone else's car.
-- energy guy, Jan 08 2007


Hot swapping the array would work, but then you have to disconnect, have exact sizes etc etc. Also - you have to have enough spare battery boxes for all the vehicles that would need charging.
-- energy guy, Jan 08 2007


It would take less energy to move the vanadium about than the entire battery. In any case, replacing a whole battery, e.g. six thousand odd cells on the Tesla Roadster, would be more like a service than filling up with petrol, unless the vehicle was designed with easily accessible batteries.

Right now, i really like this idea.
-- nineteenthly, Jan 08 2007


The Vanadium-Vanadium battery needs very careful management of the ratios of the various ionic forms of Vanadium in the electrolyte as the electrolyte is passed through the cell stack. This means a lot of associated electronics, metering, pumps, piping and sensors as well as the cell stack (where the reactions occur) and an electric motor with regulators, charge controllers etc. etc. etc. Also, the energy density of the electrolyte is way, way lower than gasoline and it is much heavier than gasoline - so range will be an issue.

Vanadium-Vanadium flowing electrolyte batteries are really only suited to large scale stationary battery situations.

Current life-cycle cost of such a device would be over US300 dollars per kilowatt hour (typical car engines put out 50 to 150 kilowatts and can go for an hour on about US10 dollars of gasoline, US2 dollars of oils and tyres and US15 dollars of amortising capital cost) - this means a V-V battery car would currently cost between 500 and 1500 times MORE to run.
-- ConsulFlaminicus, Jan 09 2007


[Consul] That's right - and similar calculations hold for other battery technologies, although not as extreme. Proponents of electric cars often simply omit the greatest consumable running cost - the batteries - when comparing them to internal combustion engined cars. Which is tantamount to fraud.

And the argument that an electric car costs more but is less environmentally destructive is also highly suspect. Aside from jaw-dropping acts of environmental terrorism like putting lead in petrol, I'm not readily convinced that, dollar for dollar, internal combustion engines cause more long-term harm than battery powered electric motors.

As to the idea, quickly charging electric cars by replacing either the entire battery, or the depleted chemicals in the battery, has been discussed for decades, at least.
-- spidermother, Feb 04 2011



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