Integrated solar-driven system for electrochemical energy storage and water electrolysis for H2 production
21 November 2017
A team from UCLA and colleagues from Tarbiat Modares University and Shahed University in Iran have devised an integrated solar-powered system for both electrochemical energy storage and water electrolysis.
They synthesized a nickel-cobalt-iron layered double hydroxide (Ni-Co-Fe LDH) on a nickel foam substrate using a fast, one-step electrodeposition approach. The Ni-Co-Fe LDH exhibited excellent electrochemical properties both as an active electrode material in supercapacitors, and as a catalyst in the oxygen evolution reaction (OER) for water splitting. A paper on their work is published in the journal Energy Storage Materials.
Employed as the positive electrode in a supercapacitor, along with activated carbon as the negative electrode in an asymmetric configuration, the ultrathin and porous Ni-Co-Fe LDH nanoplatelets delivered an ultrahigh specific energy of 57.5 Wh kg−1 with specific power of 37.9 kW kg−1 and an excellent cycle life.
As an OER electrocatalyst, Ni-Co-Fe LDH exhibited superior electrocatalytic performances with a very low overpotential of 0.207 V versus a reference hydrogen electrode (RHE) at 10.0 mA cm−2, and a small Tafel slope of 31 mV dec−1.
The team attributed the superior energy storage and catalytic OER properties of the Ni-Co-Fe LDH nanoplatelet array to both the synergistic effects among the metal species and the unique mesoporous structure of the LDH that provides facilitated charge/ion diffusion pathways and more available active sites.
Traditional hydrogen fuel cells and supercapacitors have two electrodes: one positive and one negative. The device developed at UCLA has a third electrode that acts as both a supercapacitor, which stores energy, and as a device for splitting water into hydrogen and oxygen. All three electrodes connect to a single solar cell that serves as the device’s power source, and the electrical energy harvested by the solar cell can be stored in one of two ways: electrochemically in the supercapacitor or chemically as hydrogen.
People need fuel to run their vehicles and electricity to run their devices. Now you can make both electricity and fuel with a single device.
—Richard Kaner, senior author and a UCLA distinguished professor of chemistry and biochemistry, and of materials science and engineering
Combining a supercapacitor and the water-splitting technology into a single unit, Kaner said, is an advance similar to the first time a phone, web browser and camera were combined on a smartphone. The new technology may eventually lead to new applications that even the researchers haven’t considered yet, Kaner said.
The researchers designed the electrodes at the nanoscale to ensure the greatest surface area would be exposed to water, which increases the amount of hydrogen the device can produce and also stores more charge in the supercapacitor. Although the device the researchers made would fit in the palm of your hand, Kaner said it would be possible to make larger versions because the components are inexpensive.
Resources
Yasin Shabangoli, Mohammad S. Rahmanifar, Maher F. El-Kady, Abolhassan Noori, Mir F. Mousavi, Richard B. Kaner (2017) “An integrated electrochemical device based on earth-abundant metals for both energy storage and conversion,” Energy Storage Materials doi: 10.1016/j.ensm.2017.09.010
This process could probably be fine tuned as a better way to simultaneously capture solar energy and/or split water for H2 production.
Could be ideal in all sunny places.
Posted by: HarveyD | 21 November 2017 at 05:58 AM
Capture hydrogen as a back up heat source for a heat pump and electricity for transport and all else. This makes maginfies the utility of a solar package.
Posted by: Paroway | 21 November 2017 at 12:25 PM
I clearly said that when cheap hydrogen will be produced. than sell it everywhere not in costly fuel cars but in low cost bi-fuel gasoline-hydrogen ice car. That way the transition to low pollution fuel will be easier.
Posted by: And Bri | 21 November 2017 at 08:10 PM
I don't think that would be worth the effort And Bri. Yes, it can easily be done, same with any gaseous ICE version, but i don't think the costs benefits would be there.
The fuel cell gets its benefit from being far more efficient than a gasoline /diesel engine. If you just take hydrogen, and burn it in an ICE, you might as well take methane or propane and burn that instead. Both would be significantly cleaner than gasoline, but there would be drawbacks due to initial cost and range.
If we were to generate H2 in our homes from electrolysis, or some of these more advanced methods, we could take that waste heat and put it toward heating hot water, or some radiant heating. H2 in fuel stacks is almost 2x as efficient as a typical gasoline car, exaggerating a bit but it's noticeably better than all but hybrid setups.
If we come up with cheap ways to create hydrogen, and electricity where its not competing with eachother, but rather in unity, this could prove advantageous for almost any grid application, and a good foot hold for building out hydrogen networks for transportation.
Posted by: CheeseEater88 | 21 November 2017 at 09:18 PM
Hey folks dom't believe these pseudo scientific lies. With a pure fuelcell car or truck you will be struck some day and will need to attach a becycle to your trunck to pedal the remaining of the trip. or maybe sell uour guelcell car where you are struck and buy a small gas car to finish the trip.
Posted by: And Bri | 22 November 2017 at 12:45 PM
Gor you halfwit, BMW did the multi-fuel hydrogen car quite a few years back. It only got 256 HP out of a V-12.
Now beat it.
Posted by: Engineer-Poet | 23 November 2017 at 01:26 PM
As usual, the greenie gas-freaks are totally missing the most important part of this news release:
This specific energy is well into battery territory, better than lead-acid at 30-40 Wh/kg. The specific power is stunning.
What, specifically does this mean? Let me lead you through the logic. A 1500 kg vehicle travelling at 70 MPH has a whole 204 watt-hours of kinetic energy. About 3.5 kg of these capacitors (or perhaps it's just the + electrode, with carbon electrode, electrolyte and casing extra) could store enough energy to accelerate the vehicle to 70 MPH, or absorb all the energy of braking it to a stop. This same 3.5 kg of material would be able to supply 134 kW of power—a whopping 180 horsepower.
This totally inverts the relationship between engine and energy storage in a hybrid vehicle; the electric side becomes primary. Something like a 500 cc 2-cylinder engine would suffice completely to run the average sedan; for towing, you'd be able to manage with a 1.5 liter. The ultracaps and motor drives would provide all power for acceleration to highway speed, absorb all braking energy down to a few MPH, and allow for all-wheel drive with no transfer cases or differentials.
You get a car with stellar performance, options for electronic handling enhancment, and fuel economy that a Prius can only envy—without having to fill it full of expensive batteries or scarce lithium.
If this material can stand up to automotive environmental conditions, it will be EVERYWHERE in 10 years.
Posted by: Engineer-Poet | 23 November 2017 at 09:13 PM
As E-P become a believer of H2/e-economy and REs?
Posted by: HarveyD | 24 November 2017 at 11:37 AM
Greenie gas-freak isn't smart enough to tell when he's being ridiculed.
Posted by: Engineer-Poet | 24 November 2017 at 06:44 PM
Is our Poet getting smart or brash and insolent?
Regardless of his thinking, clean and save energy production and storage will evolve. Solar energy will be leading in many (sunny) places before 2040.
H2 and FCs could play an important role for extended range e-buses, large e-trucks, e-locomotives, e-ships, heavy e-machinery, power grids and e-airplanes.
Posted by: HarveyD | 25 November 2017 at 07:43 AM
You're either too stupid to understand what you read even when the reasoning is laid out for you step-by-step, or you're so blinded by the Greenie obsession with that gas as the One True Solution that you cannot grasp when someone is specifically NOT talking about it because it's irrelevant.
I don't know what's wrong with you, Harvey, but it's definitely you.
Posted by: Engineer-Poet | 25 November 2017 at 11:03 AM
What is wrong with our anti-evolution Poet?
Why does he have to be right all the time?
Does he have a DT like personality disorder?
Posted by: HarveyD | 25 November 2017 at 01:16 PM
Things are not going to evolve into your hydrogen economy for very good reasons. Reasons that you simply ignore instead of attempting to understand and debate.
Endlessly repeating Greenie dogma which implicitly supports fossil fuels does not make you right. One of the reasons hydrogen isn't any solution is because it is most cheaply made from fossil methane.
You often add partly relevant or totally irrelevant comments on posts. Very often those comments are the only ones anyone leaves. Do you have a personality disorder where you have a compulsive need to leave little droppings, so people will know you exist? You're not contributing anything of any use to others.
Posted by: Engineer-Poet | 25 November 2017 at 01:34 PM
Extracting H2 from NG may be an interim cheaper/easier solution, heavily supported by NG producers.
Extracting H2 from water with clean solar energy (potentially supported by electricity generating/distributing groups) may become another way to mass produce environmentally clean H2 at a much lower cost?
Most NPPs will be decommissioned (at a very high cost and safety challenges) and progressively replaced with clean REs with appropriate storage units. China may be an exception to fight current unsustainable air pollution. China's nuclear projects may be scaled back due to rising cost and lower cost REs.
Posted by: HarveyD | 25 November 2017 at 02:55 PM
It's how the vast majority of H2 is made world-wide.
NG is much cheaper even at world prices. If you dispute this, show what it will cost given your figures for cost of electric power, hardware, O&M and amortization at 7%/year. Don't forget to set a fixed lifetime for amortization, either 20 years or the expected unit lifespan, and make sure that your cost of power is enough to pay for your generators (in other words, it can't be free).
I throw out this challenge because I know you are not competent to do this. If you are not competent to opine, the least you can do is be quiet.
The "appropriate storage units" are prohibitively expensive and will remain so.
If it costs too much to decommission NPPs, the obvious thing to do is never decommission them. Refurbish them as things wear out and run them forever. This has good effects on EROEI, as the energy used to construct the plant in the first place pays much bigger dividends.
Posted by: Engineer-Poet | 25 November 2017 at 08:58 PM
As usual, you continue to under estimate the total cost to properly refurbish old NPPs and/or to build new ones. Used fuel safe disposal is still a challenge to be solved and paid for.
It is well known that electricity produced by new or properly refurbished NPPs cost much more than clean electricity produced by REs. France (a world NPP leader) will reduce its dependence on NPPs from 78% to 50% by 2030 and so will Germany. China is slowing its nuclear program due to high cost and competition from REs. Japan is having problems to decide which way to go. Even USA has progressively reduced its dependence on nuclear during the last 20-30 years.
Improved longer lasting solar panels and improved wind mills/generators on higher towers will continue to outperform NPPs, CPPs and NGPPs when all cost are included and will challenge new Hydro projects.
The ideal clean power sources are still combined Hydro/REs.
Reversible Hydro plants (with reservoir) could be used to store excess REs and/or to produce energy for peak demands.
Posted by: HarveyD | 27 November 2017 at 10:24 AM
Harvey you 1d10t, the cost of the Bruce Point refurbishments is no secret. If Canada built out a set of CANDUs sufficient to supply its electric power and district heat for lakeside cities, it could have crews continuously refurbishing units which come to refit time. Maintaining the supply chain and body of experience by keeping it employed continuously would keep the cost low and predictable.
Harvey you 1d10t, it's not a technical problem, it's a political problem. You Greens won't allow it to be solved. The Canadian shield has more than enough granite that can be drilled, filled with waste and sealed for geologic time, assuming it made any sense to do so. If you're upset about waste, foist it off on the USA. Strike a deal for DUPIC fuel for all your CANDUs and have the US take it back after its second use.
It's well known that your claims are based on LCOE rather than Levelized Avoided Cost of Energy (LACE), meaning they are lies. Your unreliable energy requires backup, but you don't count the costs of that backup. When you include those costs and their pollution, nuclear is cheapest.
Not going to happen in France as sanity will return first. Germany is soon going to look at the escalating costs of the Energiewende versus the stagnant carbon reductions, and conclude that the Greens have sold the country a bill of goods and vote AfD.
Will never be able to produce when the wind doesn't blow and the sun doesn't shine. This is why the fossil fuel interests promote them.
The only 95%-decarbonized grids are the ones with combined hydro and NUCLEAR.
Posted by: Engineer-Poet | 27 November 2017 at 08:19 PM
Latest very large solar farms were contracted at 1.79 cents/kWh in Saudi Arabia. No doubt that USA could do (almost) as well in its South and South West sunny deserts.
Since most of the energy produced by solar farms is during daylight peak demand hours, a minor portion has to be stored to satisfy some of the off peak hours demands. Due to current high cost of storage units, it will still double the production cost (1.79 cents/kWh X2 = 3.58 cents/kWh). At about 3.5 cents/kWh it is much cheaper than with new or refurbished NPPs or dirty CPPs and NGPPs.
Since both solar panels and storage units will be cheaper and perform better by about 10%+/year, you do not have to be a Poet to figure out where this will lead to in 5, 10 or 20 years.
NPPs, CPPs and NGPPs may all be priced out of business. Hydro may be the exception but it will have stronger competition.
Posted by: HarveyD | 29 November 2017 at 10:17 AM
Why don't you just recommend that they use hydro, Harvey? You think it's just the thing for the USA.
Riiiiight. Do you realize what it would cost to move that power? It's 1849 miles, give or take, from Albuquerque NM to Rochester NY. That's a long (expensive), lossy and very vulnerable route. Weather, accident or sabotage could take it out anywhere along the length.
Not so necessary for the evening when the generation is 2.5 time zones west, but when the sun won't rise on the generation until hours into the workday you need a large fraction of a day of storage.I was having trouble finding current info on the cost of HVDC transmission, but this article says 2¢/kWh over 750 miles. Over 2.4 times the distance that will be OTOO 4.8¢/kWh just for transmission; you still have to pay for the generation and storage.
Given that 5¢/kWh is enough to keep current nuclear plants profitable and happy, it doesn't look good for your case.
Since the cost of acquiring new rights-of-way for these new transmission lines is going up and there are years of legal delays before any construction can start, I can tell that this isn't going anywhere for 5, 10, maybe 20 years. By that time the problem will have been solved otherwise.
Absent a carbon tax, NGPPs will take over in the American SW where NG associated with oil is close to free. Dispatchable power beats intermittent hands down. When subsidies and portfolio standards (mandates) expire, and reliability-of-supply requirements are put in place to avoid Enron-style price spikes, the ruinables will be squeezed down to the market share they actually merit—which isn't much.
Posted by: Engineer-Poet | 29 November 2017 at 07:11 PM
E.P's reasoning 134kW power didn't sound right from a 3.5kg capacitor but this is able to be delivered for 5.4 seconds.
The numbers relating to a 1,500 kg vehicle may be realised on paper but as we don't live in a perfect universe unfortunately some derating is appropriate.
The combustion engine he mentions is a small 500cc, a smaller lighter four or two seat car would have no problem seeing 0 to 70 MPH in the time allowed.
Then the combustion motor takes over.
I would question whether the cap can absorb braking energy at rates of multiples of the max energy or 134kW.
Rule of thumb for braking effort to decelerate a vehicle can be well understood by the fact that if a vehicle takes say 10 seconds to acc to 100klm /hour/over 450 meters and we need to decelerate to a stop in 45 meters,the brakes will need to absorb 10 time the energy that the motor makes to accelerate.
Rule of thumb for road cars is 7-10 time the motor power. That will vary depending on many factors- I'm thinking of modest power engines taller gearing etc that still need to be able to brake as well as the vehicle in front(fingers crossed)
I'm sure that E.P.s claims can be met - on paper or in a test deigned to show it can be done but just as sure that esp the braking claim will not fly on a production LDV.
It is still a very useful take on the possibilities of capacitors.
Not sure how this dual purpose capacitor electrolyzer could be incorporated into a motor car.
Posted by: Arnold | 30 November 2017 at 03:00 AM
Do you even math, bro? They claim 57.5 Wh/kg; divide 204 Wh by 57.5 Wh/kg to get kg. They claim 37.9 kW/kg. Multiply by the result of your previous calculation to get kW.
Remember that the motor/generator and its inverter are limited, and if you exceed limits you fall back to friction brakes. Regardless, 134 kW is multiples of the power required to brake at typical rates in traffic and even taking freeway exit ramps. Unless you're stabbing the brake pedal all the time you'd seldom have to worry about the hydraulics.
You ignore the "electrolyzer" part.Posted by: Engineer-Poet | 30 November 2017 at 11:28 AM
So I my math are unique but I'm happy enough.
To argue on the basis of an immaterial technicality we aren't discussing a space mission with a landing site measured in meters, this is a discussion of real world possibilities and I will stand by the factoring in real situations every time.
To simply ignore the reasoning for applying a (universally accepted and applied) derating or 'fiddle' factor makes conversation only possible for those with the hoop jumping skills of a circus performer.
Chill bro.
Posted by: Arnold | 30 November 2017 at 01:48 PM
So de-rate it by 50% and use 7 kg. You've still got an astoundingly light and powerful energy buffer.
Another use for this stuff is engine starting assist. Conventional batteries are limited in cold-cranking ability by ion mobility, not total energy; they can't muster enough instantaneous power to turn over an equally cold engine. Ultracaps have already been used to buffer energy for engine cranking, and this stuff appears to be well suited. Of course, it must first pass temperature, vibration and aging tests.
Posted by: Engineer-Poet | 30 November 2017 at 03:33 PM
Did you see the recent article on GCC Lamborghini are trying to build a carbon fiber bodied supercar with the cf body as capacitor as the (only?) e storage?
It took me a week to process the concept but I concluded that it should be possible to build a multilayered capacitor shell or body of this area that would certainly have phenomenal performance.
I am not that well qualified to run the numbers but know just enough to feel well - a 'little weak kneed'.
http://www.greencarcongress.com/2017/11/20171107-lambo.html
"Innovative materials. To support this revolution in energy storage systems, materials and their functions have to change, too. Lamborghini aims to further develop its leadership in the design and production of carbon fiber structures and parts, enhancing its ability to develop features and functions that take lightweight materials to the next level.
For this reason, the cooperation with Prof. John Hart will investigate the new manufacturing routes for carbon fiber materials constituting the bodyshell of the Terzo Millennio, which will also act as an accumulator for energy storage and enable the complete body of the car to be used as a storage system."
Posted by: Arnold | 30 November 2017 at 04:53 PM
Large amounts of electrical energy and vehicle skins don't mix. Even if it's limited to a few volts, anything that bridges the two plates is going to dump all the stored energy as a massive electric arc. Nobody in their right mind would approve that on an on-road vehicle.
Posted by: Engineer-Poet | 01 December 2017 at 07:49 AM