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#1 2019-06-13 07:20:10

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 3,526

Flow Battery

GW Johnson wrote:

Given a grid-scale storage solution,  the intermittent renewables (both wind and solar) really could dominate the mix,  and their industries demonstrably offer more jobs that are not automatable-for-profit,  at least for some decades yet.  Some grid-scale storage solutions,  such as the flow battery,  are getting close to practicality,  despite the chronic under-investment in such technologies.  That under-investment is driven by the same evil villain:  big-money politics.

For Louis ...

This is just the sort of ambitious, optimistic idea I would look for from members of NewMars forum!

The solar panels don't need to be deployed from the battery ship!  They can be permanently deployed on the great number of uninhabited islands that already exist above and below the equator, and there is an abundance of sea shore with excellent insolation on, above and below the equator.

The battery ships could use the flow technology that GW Johnson has mentioned in previous posts, which would be appropriate for large ships.

The chemical mixture could be charged and then delivered to ports where it would be used directly to feed the electric grid, or it could be shipped inland.

What is needed for a project like this to succeed, is for a visionary leader with financial knowledge and skills, and the drive of a Musk or Bezos to convince investors.  As far as I can see, there is nothing in the way of technology that does not already exist.

(th)

louis wrote:

Not so very different from my idea of huge solar battery tankers - 500,000 tonnes...sailing into maximum insolation areas, spreading out their 30 mile long flexi-PV floating panels over the ocean, little like trawler nets, and charging up the 500,000 tonnes of batteries with solar power...then they sail back to port in places like the UK or USA and feed the power into the grid. Assuming battery development to 400Whs per Kg that would mean each one would have 200 GwH of power to deliver. In the UK enough to keep the whole grid going for about 5 hours I would estimate. So a fleet of 6 should be able to provide electricity for 3 days.

Edit: Thinking about this further ... the flow batteries could be charged at the permanent sites and the liquid simply piped over to the vessels for shipment.

It seems to me (without attempting math as others here are able to do) that this process would be much more efficient than making ammonia or methane from atmosphere and ocean sources would be.

I don't know what chemicals are involved in flow batteries, so don't know what challenges would come with attempting to ship by pipeline or ship, but would greatly appreciate any information other forum members might provide.

The ships could be powered with electric motors driven by part of the payload.  That should appeal to potential funders of green energy projects such as this one would be.

Edit 2: It didn't take long for Google to find existing large scale flow battery projects ...

Here is a link to one article:
https://www.energy-storage.news/news/ch … eds-more-m

Apparently these are all planned for land.  Louis is the first person (I know about) who is thinking of remote locations for collecting solar energy and shipping it to land locations for use.

Edit 3: https://www.viznenergy.com/

Louis, the company at the link above is located in Montana.  I'll give you the opportunity to write them with your shipment idea.

I note that (apparently) a business opportunity has opened up for rental of electrolyte for flow batteries.  This option lowers the up-front cost of building a flow battery facility.  It allows the renter to make a buck while the electrolyte is in service, and then the materials are 100% recoverable.

Edit 4: Taking up the question of energy density ... it is low, but HOW low, and does that limit its value for shipment of charged electrolyte?

https://en.wikipedia.org/wiki/Vanadium_redox_battery

The main disadvantages with vanadium redox technology are a relatively poor energy-to-volume ratio in comparison with standard storage batteries (although the Generation 3 formulation has doubled the energy density [11] of the system), and the aqueous electrolyte makes the battery heavy and therefore only useful for stationary applications. Another disadvantage is the relatively high toxicity of oxides of vanadium (see vanadium § Safety).

Energy density
15–25 Wh/L (54–65 kJ/L)

Flow batteries are not on this chart.  Lithium ion batteries are in the lower left corner.

Energy Density chart:
https://en.wikipedia.org/wiki/Energy_density

(th)

Last edited by tahanson43206 (2019-06-13 11:36:59)

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#2 2019-06-13 16:56:20

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

GW Johnson wrote:

Myself,  I'd like to see some resources and priority placed on the flow battery concept.  It seems well-suited for grid-scale energy storage using tank farms of a type we already build anyway.  The idea would be to take the intermittency out of solar and wind,  so that they could be more than 15-20% of the source mix.  Really good near-term potential there:  years,  not decades,  away.

GW

Solar cell island mean you need to be able to defend them. Had to look up the https://en.wikipedia.org/wiki/Flow_battery
A wide range of chemistries have been tried for flow batteries.

It seems like we are making a working fluid ionic such that one is negative in charge while the other is positive. The fluid of each is isolate and are allowed to equalize along a membrane but other wise the potential power is the casings that the fluid flows through.
That said the fluid would need to be stored in a non-metalic container as well as shipped in that manner as well in the tanker.
To create flow is via pumps which are a power loss in the design. Other power losses are in the moving of the fluids from the battery and tanker as well as from the charging system.

https://www.sciencemag.org/news/2018/10 … n-and-wind

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#3 2019-06-13 18:41:33

kbd512
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Registered: 2015-01-02
Posts: 3,723

Re: Flow Battery

Louis or GW,

Will these flow battery ships only contain non-toxic chemicals that don't kill everything in the water, including a repair diving party, if they leak out of the ship?

Given the numerous complaints about oil tanker ship spills, this seems like a reasonable question.

The Seawise Giant was 657t at full load, so I guess this is a plausible, if potentially impractical idea.

Top 10 World's Largest Ships

From the article:

Fully laden, her displacement was 657,019 tonnes (646,642 long tons; 724,239 short tons), the heaviest ship of any kind, and with a draft of 24.6 m (81 ft), she was incapable of navigating the English Channel, the Suez Canal or the Panama Canal. Overall, she was generally considered the largest ship ever built,as well as the largest self-propelled manmade object ever built.

Any ship incapable of navigating the English Channel may prove very difficult to get close enough to land for short-ish power cables back to a land-based substation.

I think something more along the lines of a series of smaller barges, towed into position and moored to the continental shelf, would be more practical.  Try to imagine that routine maintenance of these vessels will be required and a single massive ship is much more difficult to work on.  As someone who has served in the Navy that was in dry dock for repairs when I arrived, I can personally attest to the time and expense of dry dock repairs on large ships.

Did I mention that flat bottom barges are a comparably low cost way of storing liquids, such as fuels or chemicals, and that they're easier to take into and out of dry dock?  Tug boats can tow them into position, only moving them around as required.  Since we're not going to tow these things to the middle of nowhere, this would seem to make a lot more sense.  Ships also require crews, whereas barges do not.  In the Navy, we would store bunker fuel in barges or pumping stations on land, emptying and inspecting them as required by law.  I expect chemical tanks for a flow battery would have similar inspection requirements.

Why not use something like this instead of a much more expensive ship that may not even be able to transit a body of water as deep as the English Channel?:

DAMEN STAN PONTOON® B36 RANGE

Edit: Based upon the info provided by tahanson43206, it looks like the Vanadium redox reaction flow batteries are 40 cubic meters per MWh.  That means that 1GWh would require 40,000 (Edit: Apple's not-so-helpful auto-correct feature apparently removed what I wrote, but the 40,000 should be 40,000,000 cubic meters of space) cubic meters of space, equivalent to a barge with internal dimensions of (100m x 40m x 10m), or roughly the size of one of those pontoon barges.  That's 1,000 barges to store 1GWh worth of power.

A 70% efficient LNH3 fuel cell would require 36.3g/H2/kWh or 36.3kg/H2/MWh or 36,300kg/H2/GWh.  LNH3 is 105g/L or 2.892kWh/L, so 1GWh requires 345,781,466L of LNH3 or 345,781 cubic meters of space.  Therefore, 8.6 LNH3 barges would be required to store the same amount of power as 1,000 flow battery barges.

For those here who are counting-enabled, what energy storage medium is looking better for grid storage, the flow batteries or the LNH3?

Let's pose another basic math problem here:

Louis wants to store 1GWh worth of electricity to power a small coastal town because the Sun doesn't shine at night and the wind doesn't always blow.  His energy storage options include:

A. CH4 / Natural Gas (8.8kWh/m^3)
B. LNH3 (2.892kWh/L)
C. Vanadium redox flow batteries (25Wh/L)

Which of the following ambient temperature energy storage mediums consumes the least volume and provides the greatest specific energy (energy density)?

Hints:

1 cubic meter / 1m^3 contains 1,000 liters.

Liquid Methane / Liquefied Natural Gas will not remain liquid at ambient temperature at any reasonable pressure.  It must be kept at cryogenically cold temperatures using active refrigeration, which consumes electrical power, to remain liquid.  We actually do this on a routine basis to transport LNG via tanker ship or truck to pumping stations, but only at tremendous energy cost.

Lead-acid car batteries store about 30Wh/L.  Therefore, the "best" redox flow batteries are not quite as "energy dense" as conventional Lead-acid car batteries, though most are considerably lighter- meaning much better gravimetric energy density.

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#4 2019-06-13 18:49:05

tahanson43206
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Registered: 2018-04-27
Posts: 3,526

Re: Flow Battery

For SpaceNut #82 ...

Good point about including site security in planning for staffing.  It is my understanding ALL land in all oceans has been claimed by one state or another over the centuries, so rent is part of the price of doing business.  however, (depending upon the nation), it may be possible to secure protection from the sovereign power in case of a dispute.  However, ordinary piracy would (most likely) be the responsibility of the company.

The science Magazine link you provided seems to be a fairly comprehensive summary of the field, given that it is several months old at this point. 

Hopefully others in the forum will assess the potential of extending Louis' idea (of shipping solar collected energy) from the ocean to customers to include flow battery technology, early though it may be.  My main concern is the disappointingly low energy density. 

However, these are early days .... according to one of the articles cited in posts above, the technology was only proven in 1986 (in Australia), so it is possible that it will attract some serious attention, and the energy density may be improved beyond what has already been accomplished.

(th)

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#5 2019-06-13 19:01:36

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

Currently wind power using old oil rigs would also be an option for an ocean islands which would also work in the same manner for the flow battery concepts just a difference source for the free energy to make the stored possible.

JoshNH4H wrote:

I can't say I have any new ideas on the storage front.  At the moment, we have a bunch of imperfect battery technologies that we can start trying to deploy.  No technology is perfect but there are lots of avenues for potential research and development.  Terraformer brought up sodium ion batteries, an idea which I think is good. 

GW brought up flow batteries for their ease of use and that seems like a good idea. 

Louis brings up hydro storage, which has questionable economics in that you need to move massive amounts of water but which is in use now and likely will continue to be.  I have brought up the idea of a global power grid as an ultimate solution, which has its own challenges but also, to my mind, the potential to be way cheaper than any of the solutions brought up thus far.  I don't believe it requires room temperature superconductors, although without a doubt they would help.

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#6 2019-06-13 19:58:26

kbd512
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Registered: 2015-01-02
Posts: 3,723

Re: Flow Battery

Is there even enough Lead or Vanadium on this planet to make this work at any significant scale, meaning something that would actually matter in the grand scheme of things?

Are we spending money to do great things or spending money to please our vendors and battery technology lobbies?

Someone please show me a working 2.5kWh/L flow battery that isn't made from unobtanium.  Whenever that happens, then let's talk about batteries.  Until then, or unless the materials in these flow batteries are readily available in gigaton quantities and literally cheaper than dirt, let's spend a little time on practical alternatives.

Edit:

1 cubic meter / 1m^3 of LNG / Methane weighs .717kg.

Liquefaction of LNG requires 850kWh/kg or 609.45kWh/m^3.

The mathematically-enabled or ideologically-unmotivated amongst us will quickly spot a small mathematics problem here.

1m^3 of Methane only contains 8.8kWh.  We need 69 times more power than the Methane can provide to begin with in order to liquefy / densify it for storage purposes.  After that, we have to continue to provide input electrical power until the Methane is consumed by a fuel cell or gas turbine.

Is it apparent at all to anyone else here why this is such a bad idea?

Can anyone else connect the dots as to why it is that we generally just pump non-liquefied natural gas, via pipeline, instead of liquefying it, whenever possible?

Is Uranium, with its specific energy / energy density of about 24MWh (yes, that's 24 Million Watt-hours) per kg, or 457MWh/L, looking mighty tempting right about now?

Edit #2:

Thermodynamic and heat transfer analysis of LNG energy recovery for power production

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#7 2019-06-14 13:19:17

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 3,526

Re: Flow Battery

For kbd512 re #86 ...

Thanks for the link to the study of trying to recover the energy "invested" in cold methane for shipment.

As you point out in your message, energy is required to liquefy natural gas for shipment.  The authors appear (to me at least) to be exploring the possibility of treating the cold liquid as a heat sink (where sea water is the heat source) for the purpose of generating energy.

I scanned the article to arrive at this assessment, and will keep it in mind to read more carefully if time becomes available.

However, in the mean time, I'd like to toss out the idea for forum members to consider:

Direct production of electric  current is possible using the

There is a significant temperature difference between LNG and sea water, and the effectiveness of the thermoelectric effect is greater as the difference in temperature between source and sink increases.

There would need to be an investment to realize any potential gains from using this method, or a mechanical method, for that matter, so I can easily understand why an investor in LNG shipments would decide not to bother.

***
Would you be willing to apply your considerable talents to the question I posed earlier in this topic, regarding the potential value of storing energy in a flow battery for ocean shipment to a customer.  This was a spin off of a suggestion from Louis to use the ocean as a location to collect solar power.

A flow battery energy density is so low that I am skeptical it would be practical for shipment of energy as Louis proposed.

I noted your observations about vanadium.  Apparently China has a sufficient supply so they can invest in major flow battery installations.  Other nations may not be so lucky.

However, other metals are under study to see if they can provide similar functionality.

(th)

Last edited by tahanson43206 (2019-06-14 20:43:16)

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#8 2019-06-15 11:12:41

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,078
Website

Re: Flow Battery

A thought regarding use of flow batteries for grid-scale storage:

The grid is on land.  Most of the wind farms and solar farms are on land,  or very near it.   Why put flow batteries in ships at sea,  when most of the wind and solar electricity generation is not at sea?

On land,  tank farms are cheaper to build than tanker-type ships or barges.  Land-based tank farms are less subject to damage by severe weather.  There is no fundamental limit to the size of a tank farm,  other than available land on which to site it.  And spill cleanups are easier on land than at sea.

There is a fundamental limit to how big a ship or barge you can build:  it derives from the fact that tensile strength of steel does not scale with size,  while its weight and the values of applied loads do scale with size.  Hogging and sagging over ocean swells limits ship lengths to at most around 1300 feet.

Even for offshore wind farms as in Denmark,  it would be more practical to site the tank-farm-type flow battery on shore.  Putting chemical-laden ships or barges permanently offshore is just not possible on the US Atlantic or Gulf coasts.  This is because of the very real risk of catastrophic hurricane damage,  something Denmark does not face,  stormy as the North Sea is.

I'm no expert on the flow battery technology,  so I cannot speak as to which chemicals are involved or how hazardous they are.  There seem to be multiple possible combinations,  and things look rather favorable in the lab scale experiments done to evaluate feasibility.  It's promising,  so it deserves development effort to select and scale-up the "best" combination,  something inherently defined by the imposition of  multiple real-world constraints (such as weather damage risks,  spill clean-up,  and any identifiable scaling limits) rather than just efficiency or costs.

But don't muck it up trying to implement a less-practical form at sea with pre-imposed fundamental scaling limits and risks of catastrophic hurricane damage.  That just does not seem smart at all.

GW

Last edited by GW Johnson (2019-06-15 11:22:24)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#9 2019-06-15 14:31:09

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 3,526

Re: Flow Battery

For GW Johnson re #90

There are two (primary) contributors to this idea, starting with Louis, who proposed (as I recall) collecting solar energy from ocean going vessels.

I thought it would make more sense to place solar energy collection facilities on land, and to ship the energy carrying material to where it needs to go.

However, to your specific point about flow batteries at sea .... it seems to me that this technology is worth considering for delivering power to ocean going vessels, but I acknowledge up front that the energy density is (currently) so low that it would probably not be competitive with methane or ammonia.

The fact is (to the best of my knowledge) there are regions on Earth where energy is in short supply, so importing material is a solution that has been carried out over a number of years.  The earliest example I can think of is a British expedition to explore the Arctic passage.  The ships were sail driven, but the expedition was fitted with coal burning equipment for food preparation and possibly for heating.

Thus, the potential exists for collecting solar energy near the equator (there is plenty of land along and near the equator), and delivering it to customers away from the equator. 

A number of countries are currently shipping coal to customers who need energy, and of course multiple countries are shipping oil and gas.

The issue at hand (as I see it) is that the planet could use a LOT of energy that does not increase the carbon burden in the atmosphere, and both ammonia and flow battery fluids appear to meet that test.  Methane could be a long term energy carrier if it is made from atmospheric CO2 and sea water hydrogen, because the carbon flows will balance out.

(th)

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#10 2019-06-15 14:40:46

kbd512
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Registered: 2015-01-02
Posts: 3,723

Re: Flow Battery

tahanson43206,

My thoughts on this are in agreement with what GW stated.  Vastly larger tank farms than ships or barges can be constructed on land, at a fraction of the cost.  Anything we put in the ocean is subject to rigorous engineering standards that dictate size and materials used, therefore cost.  Making and storing CH4 as LCH4, whenever it can be pumped out of the ground, makes no sense.  It uses even more energy than the previous solution, which must come from somewhere.  Similarly, using flow batteries to power ships or barges or for storing energy offshore, doesn't make any sense unless that's where the energy will be consumed.  The barges are less expensive than ships, yet more expensive than tank farms on land.  We don't put tank farms in the oceans because it makes no economic or practical sense to do so.

Batteries have the advantage of not requiring 24/7 chemical refinery operations, even though flow batteries are technically a simplistic form of chemical refinery, continually separating and combining chemicals in a reversible process to store or generate power.  The practicality of a given solution is a function of materials and fabrication cost and/or availability, maintenance schedules, staffing requirements, and total system complexity / number of moving parts.  By those metrics, the only metrics that matter as it relates to the viability of an energy storage system, flow batteries are more cost-effective to use than petrochemical plants, even if the plant is only making the simplest hydrocarbon fuel that we use.

Flow batteries for ocean-going transport remains a pipe dream, specifically because the energy density is insufficient.  Small attack submarines use Lead-acid batteries with slightly better energy density, but that provides enough electrical power for perhaps a day or two before snorkeling to recharge them with Diesel engines is required.  Crossing the Atlantic or Pacific on a single charge is entirely out of the question.

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#11 2019-11-22 22:59:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

[Scientists design new grid batteries for renewable energy

aquapim-membrane-grid-battery-concept-hg.jpg

Giant batteries designed for the electrical grid - called flow batteries, which store electricity in tanks of liquid electrolyte - could be the answer, but so far utilities have yet to find a cost-effective battery that can reliably power thousands of homes throughout a lifecycle of 10 to 20 years.

Schematic of a flow battery with an ion-selective AquaPIM membrane (noted in beige). affordable battery membrane - from a class of polymers known as AquaPIMs. This class of polymers makes long-lasting and low-cost grid batteries possible based solely on readily available materials such as zinc, iron, and water. The team also developed a simple model showing how different battery membranes impact the lifetime of the battery, which is expected to accelerate early stage R and D for flow-battery technologies, particularly in the search for a suitable membrane for different battery chemistries.

Most grid battery chemistries have highly alkaline (or basic) electrodes - a positively charged cathode on one side, and a negatively charged anode on the other side. But current state-of-the-art membranes are designed for acidic chemistries, such as the fluorinated membranes found in fuel cells, but not for alkaline flow batteries. (In chemistry, pH is a measure of the hydrogen ion concentration of a solution. Pure water has a pH of 7 and is considered neutral. Acidic solutions have a high concentration of hydrogen ions, and are described as having a low pH, or a pH below 7. On the other hand, alkaline solutions have low concentrations of hydrogen ions and therefore have a high pH, or a pH above 7. In alkaline batteries, the pH can be as high as 14 or 15.)

Fluorinated polymer membranes are also expensive. According to Helms, they can make up 15% to 20% of the battery's cost, which can run in the range of $300/kWh.

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#12 2019-12-14 22:42:00

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

Lockheed Martin announces Teaming Agreement with TC Energy on innovative flow battery technology

GridStar Flow, Lockheed Martin's innovative flow battery technology. This cutting-edge energy storage system is capable of storing six to 12 hours or more of energy and dispatching it as needed.

duration is not what wattage is saved only the draw off rate.

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#13 2019-12-15 12:03:38

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,078
Website

Re: Flow Battery

I told you this idea had merit. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#14 2019-12-15 15:21:58

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

I would agree that its got the potential for what we need to store surplus energy for later use.
Its only as good as the size of the capacity for storage.
The materials used to make it as in any battery storage rechargeable can and are capable of.
So its back to the liquid used for the battery that is used for the storage and of safe use.
We could do this even with a standard lead acid battery chemistry but the circulating pumps for moving the acid would need to have a different turbine propeller material and so would the supply tubing as well as the storage tank but these are do able.

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#15 2019-12-15 16:22:51

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 532

Re: Flow Battery

Vanadium redox battery - energy density 55-64KJ/litre.  I agree with others here that this is far too low to be useful for powering ships or practically any mobile application.  It is almost 3 orders of magnitude smaller than diesel or liquefied natural gas.  OK for small amounts of grid energy storage, where you need large amounts of power for a short time for frequency control.  That sort of thing is useful if a wind farm crashes off the grid and it will take some minutes to bring gas turbines on line to fill the gap.  A fast acting power supply is needed in those circumstances.  It need not be cheap per kWh, as it is there to fill small gaps.


Interested in space science, engineering and technology.

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#16 2019-12-27 15:28:59

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

The case for mars storage is with the knowledge that winter much as it here on earth is much lower in the recieveing of solar power for the period of charging from panels of a fixed quantity and that we will need a reserve for those months of winter to offset the lower amount not counting dust storms.

https://en.wikipedia.org/wiki/Flow_battery

https://en.wikipedia.org/wiki/Electrolyte

In the fuel cell flow battery it seems that hydrogen is one of the top chemical components to make use of in a flow battery cell membrane type.

High-energy-density dual-ion battery for stationary storage of electricity using concentrated potassium fluorosulfonylimide

The new design from 24M allows customization of separate electrolytes for the anode and cathode.

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#17 2020-02-08 19:31:16

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,699

Re: Flow Battery

4 topics that meantion this:
Nonflammable electrolyte for high-performance potassium batteries

This novel electrolyte contained triethyl phosphate as the sole component of the solvent. This substance is known as a flame retardant. It has been tested in lithium-ion batteries, but only very high concentrations provided enough stability for long-term operation, too high for industrial applications.

The battery industry demands dilute electrolytes, which are cheaper and ensure better performances. They combined the phosphate solvent with a commonly available potassium salt and obtained an electrolyte that did not burn and allowed stable cycling of the assembled battery concentrations of 0.9 to 2 moles per liter, which are concentrations that are suitable for larger scales; for example, in smart-grid applications.


http://dx.doi.org/10.1002/anie.201913174

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