Vanadium redox battery | Hacker News Reader

Vanadium redox battery

en.wikipedia.org

35 pointsfpoling31 comments

These are fascinating batteries. Yes, their energy density is less than Li-Ion but, are most suitable to cater to intermittent power sources such as Solar and Wind.

Hopefully, with enough space, a solar or wind generating station can be turned into a base load station. I guess that's where data analysis and computing will help.

An intelligent power controller / charger could theoretically turn a single wind turbine into a miniature base load plant, i.e, a power source that supplies constant power, buffered by these flow batteries.

I am hopeful that with better materials, not only with the flow batteries be eco-friendly, but also more energy dense.

Also, in the future, such batteries hopefully could make an individual house completely grid independent.

There's no real compelling reason to locate the batteries near the generator.

For maintenance free batteries, coupled with an intermittent power source and an intelligent controller, the whole system coukd act as a constant power source.

I think the point is, from the perspective of electricity grid maintenance, it doesn't matter much (given sufficient transport capabilities) if you stuff all the wind turbines on one end, and all the redox batteries on the other end of the country.

No need to integrate the production and storage solutionss at all.

> given sufficient transport capabilities

I feel like that is fairly big thing here. In practice power grid capacity is very much finite.

There's no reason you couldn't have region-local storage locations underground. There are lots of huge natural and artificial cave systems that would be perfect for temperature control of even enormous batteries. I don't think transmission losses to a regional underground storage facility will be a huge concern.

Not next door no, but they are going to have to be in roughly the same region, because power losses over long distance transmission become significant in pretty short order.

I think you put the batteries near the load point. Transmission losses are more painful for higher cost energy (battery storage), than low cost (excess wind power).

They don’t operate below 10c or above 40c due to their chemistry so unless your location has a very temperate climate 24/7/365 the energy density is the least of your worries.

The 24/7/365 aspect can be solved by moving them sufficiently underground. Underground environments are naturally the yearly average temperature of the surface.

And even if digging is too expensive, there's another option: buffer the buffer with a big tank of water. That is, put the tank of electrolyte inside an outer tank of water.

As long as your average temperature is between 10C and 40C, with sufficient volume of water you'd have enough thermal mass to ride out the day and night fluctuations.

In some climates, you might need to get fancier to try to nudge the temperature in the right direction. Hot climates shouldn't be much of a problem, but even if they are you could use fans or vents to create a system that's insulated and shaded during the day but open to outside air at night. In cold climates, you might want to have a greenhouse kind of setup to capture some extra heat and prevent convection cooling so it stays above 10°C.

This might work in Europe but not in the states where the summertime temperature might be around +25 and the wintertime temperature might sometimes reach -25. The lake where my parents live freezes thick enough to drive a pickup truck on it.

Read the parent comment again. As long as some of the time temperatures are in a viable range, it isn't a problem.

I would tend to disagree. Even if the water buffer is 20 feet thick, it will freeze all the way through, at least where I live. I mean you can buffer sub-freezing temperatures for a few days, a couple weeks, but not for 6 months.

Oh, and since water expands when it freezes - the container will rupture, too.

Hot climates are a huge problem because temperatures easily reach 40c in Africa and the Middle East and that is just ambient temperature you are forgetting the heat produced by the battery itself.

Li-ion doesn’t have this problem as much heck the PANASONIC NCR-18650 can be discharged safely even at 60c.

Battery capacity scales with volume, whereas external heating/cooling losses to the environment scales with surface area.

That means, for any large enough scale plant, the cost to keep it at a fixed temperature diminishes to insignificant.

Correct, and you can add arbitrarily thick insulation.

Vanadium batteries are very promising, however the energy density is the main issue here. Lead Acid batteries have a better ratio however obviously lead is toxic and it requires more than just lead. The fact that Vanadium batteries capacity is limited to just the size of the tank (slight oversimplification) is a positive for sure, their life span is also a positive factor. It also, while classed as toxic, is not classed a seriously hazardous.

Salt water battery looks better: https://en.wikipedia.org/wiki/Salt_water_battery

That article is very low on actual electrochemical details. Here's one of the research papers on high performance salt water electrolyte batteries: http://sci-hub.tw/10.1126/science.aab1595

Like most redox/flow batteries they have a very big shortcoming and that is a very limited operating temp range for vanadium it’s 10-40c that means they’ll need environmental controls installed in almost every case.

Li-ion generally needs HVAC too, and if you only need HVAC at 104F that's not too substantial a cost for southern (US) solar available regions.

Modern Li-Ion can operate at 0-45c in "fast charge" and there are even higher ranges being developed, there is a huge difference between 10-40 and 0-45 as far as suitable environmental locations go.

Li-Ion can be charged at 0c or even below in some cases, with Vanadium Redox you get crystallization at 10c and the battery stops working it's not like Li-Ion where you lose some charge and you need to charge at a lower current and the charging it self will bring back the inner temp of your battery pack to fast/full charge levels.

Given that these batteries would be used mostly in stationary applications, where space is less of a problem, the only question is how much extra power would the heaters and/or coolers need, and how much waste heat the charge/discharge releases (some of the waste heat could be used instead of the heaters, but would put more demand on the cooling system). Unless the amount of waste heat is too high, it doesn't sound like too much of problem to me; given proper insulation, most of the heat would come from the battery itself.

Cooling/heating Li-Ion batteries which have a wider range and are mechanically easier to cool than liquid Redox batteries is a big challenge, this one is a much bigger one.

For grid storage, density is entirely a non-issue.

The temperature limits issues can be (in most cases) solved by simply putting the batteries underground.

If you can go deep enough, temperature is almost constant, check, as an example, Fig. 4 here:

https://www.builditsolar.com/Projects/Cooling/EarthTemperatu...

Vanadium is the latest beneficiary of the battery craze

A metal used to harden steel could also help prevent global warming

https://www.economist.com/business/2018/07/21/vanadium-is-th...

One company attempting to make commercial products:

https://www.google.com/search?q=storen+technologies&oq=store...

On a bigger Grid scale:

https://en.m.wikipedia.org/wiki/UniEnergy_Technologies

I'm super confused...a lot of people say that this battery works only between 10-40C but I remember a couple weeks ago and there was a Stanford article on how they made a mebrane operate at room and high (200C). Is the 10-40C a limit on Vanadium or the membrane used?! If it is the membrane, does that mean the article is click bait?!

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