Bleeding Edge - Flow Batteries for EVs

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peakbagger

Minister of Fire
Jul 11, 2008
8,845
Northern NH

Definitely early stage but this would change a lot for the EV scene. Instead of charging up, just fill up with "flow juice" and get the benefits of an EV.

Back a few years ago, the charged liquid on the tech we were looking at could last for weeks with no drop in charge. The supplier claimed that it might not taste to good, but someone could drink the liquid being used. The flow battery would be paired up with natural gas engine generator supplying baseload, the battery would be "charged" when the demand dropped below the generator output and during the night when the demand was low they would build up storage in the battery and then use it during the day. Unfortunately the project didnt go anywhere.
 
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Are flow batteries appropriate for EV use?
 
As the article says, if the energy density of the "flow juice" goes up, yes. Practically in the near term, I doubt it for light vehicles. Its ideal for stationary batteries as energy density is not as important.
 
Yes, we have a couple successful Flow battery manufactures in the NW. They work well but are massive and heavy. If the engineering challenges with keeping the nanoparticles suspended indefinitely has been solved, this could be an interesting alternative. Maybe start out with the marine industry first.
 
Very interesting. It sounds crazy ambitious to launch a complete new car assembly infrastructure and novel fueling infrastructure. The cost to do so will be staggering and dependent on not only the fueling ubiquity, but also on the practical roadability and desirability of the car(s). I can't say I am enamored with the roadster interior design, but that could change. In the least, this would require a huge capital investement. The potential for a home battery storage system is intriguing and might help boost the bottom line.

 
Until the time any of this tech, including lithium, is mature I liken it to buying all your VCR movie titles on Laser disk back in the 90s.

If through any "nano" technology we end up with a huge volume of nano sized particles in our eco system I wonder the long-term effects on living matter.
 
Very interesting. It sounds crazy ambitious to launch a complete new car assembly infrastructure and novel fueling infrastructure. The cost to do so will be staggering and dependent on not only the fueling ubiquity, but also on the practical roadability and desirability of the car(s). I can't say I am enamored with the roadster interior design, but that could change. In the least, this would require a huge capital investement. The potential for a home battery storage system is intriguing and might help boost the bottom line.

I think that the intent is that the flow battery would normally run backwards to charge up the liquids at home at a standard charging station and could also be charged off EV charging stations. The bonus would be that if someone is in rush, they could just change out the "flow juice" at a central station. If the liquids truly are "safe" my guess is standard gas station infrastructure could be adapted to sell this product at a pump.

One of the many "details" to be worked out in a transition to EVs is the current business model of gas station/convenience stores. Currently most sell gas at near cost with the profit coming from people walking in and buying overpriced convenience items at a high volume of traffic. Supercharger stations do not work as well for traffic flow as the charge time of 15 to 20 minutes means lots of bodies clogging up the place nursing a coffee that they normally would buy and drink on the go means the overall traffic volume is less.

If on the other hand an EV owner could have a premium option of a quick fill up or a 20 minute wait, that restores the traffic volume. From a grid point of view, having a large tank of stored power is of great value in managing the grid.
 
It was unclear reading the article if charging at home (to replenish the fuel tanks) was part of the design. ;hm
 
I agree.
 
It was unclear reading the article if charging at home (to replenish the fuel tanks) was part of the design. ;hm
Yes, I was looking for that. It sounded more like a filling station model.
 
More detail from a more legit source but does not answer the question https://spectrum.ieee.org/flow-battery-2666672335
Seems to emphasis the filling station model to exchange fluids and not a home charging setup. Still, based on this model, if one had a home flow battery system there would need to be a delivery truck to exchange fluids.

If home charging isn't feasible, I think developing lithium and solid state battery tech will win. It has the strength of home charging which is more disruptive and practical for most people and delivery companies. I maybe went 2 or 3 times to a gas station in 2023 and that was to fill the van on trips. I don't miss it at all.
 
More detail from a more legit source but does not answer the question https://spectrum.ieee.org/flow-battery-2666672335

Based on the wording of the article, is sounds like regenerating the electrolytes will be done at a central plant, not onboard the vehicle.

And that seems like a fatal flaw to me, requiring a massive distribution system, and parasitic losses in the energy needed to ship the electrolyte around.

NVM, from the article:

The fuel would be created as needed, he says, eventually at such a scale as to replace fossil fuels. The fuel could be transported to depots much as gasoline is today, either by tanker trucks or via existing upgraded pipelines. At the depot, the spent fuel could be recharged with electricity from any source—solar, wind, hydroelectric, nuclear, or fossil fuels. The recharging could also be done at a service station or in the EV itself. In the latter case, the recharging would work just as it does for today’s battery electric vehicles.

And:

What you do not want to do is throw that stuff away. “What is collected is the most valuable part of the battery,” he says. “There are processes to easily reconstitute the active material into a new nanofluid that can be reused.”

the use of 'processes' suggests something more than merely running the flow battery in reverse. ???