Researchers efficiently charge a lithium-ion battery with solar cell

Consumers aren't embracing electric cars and trucks, partly due to the dearth of charging stations required to keep them moving. Even the conservation-minded are hesitant to go electric in some states because, studies show, if fossil fuels generate the electricity, the car is no greener than one powered with an efficient gasoline.

Charging cars by solar cell would appear to be the answer. But most cells fail to meet the power requirements needed to directly charge lithium-ion batteries used in today's all-electric and plug-in hybrid electric vehicles.

Researchers at Case Western Reserve University, however, have wired four perovskite solar cells in series to enhance the voltage and directly photo-charged lithium batteries with 7.8 percent efficiency—the most efficient reported to date, the researchers believe.

The research, published in the Aug. 27 issue of Nature Communications, holds promise for cleaner transportation, home power sources and more.

"We found the right match between the solar cell and battery," said Liming Dai, the Kent Hale Smith Professor of and engineering and leader of the research. "Others have used to charge , but not with this efficiency."

In fact, the researchers say their overall photoelectric conversion and storage outperformed all other reported couplings of a photo-charging component with lithium-ion batteries, flow batteries or super-capacitors.

Perovskite solar cells have active materials with a crystalline structure identical to the mineral perovskite and are considered a promising new design for capturing solar energy. Compared to silicon-based cells, they convert a broader spectrum of sunlight into electricity.

In short order, they have matched the energy conversion of silicon cells, and researchers around the world are pursuing further advances.

Dai's lab made multilayer , which increases their energy density, performance and stability. Testing showed that, as desired, the three layers convert into a single perovskite film.

By wiring four lab-sized cells, about 0.1 centimeter square each, in series, the researchers further increased the open circuit voltage. The solar-to-electric power conversion efficiency was 12.65 percent.

To charge button-sized , they used a lithium-ion-phosphate cathode and a lithium-titanium-oxide anode. The photoelectric conversion and storage efficiency was 7.8 percent. Through 10 photo-charge/galvanostatic (steady current) discharge cycles lasting nearly 18 hours, the technology maintained almost identical discharge/charge curves over all cycles, showing high cycling stability and compatibility of the components.

"We envision, in the not too distant future, this is a system that you could have at home to refuel your car and, eventually, because can be made as a flexible film, they would be on the car itself," said Jiantie Xu, who, with Yonghua Chen, is an equally contributing first author of the study. Both are macromolecular science and engineering research associates in Case School of Engineering.

The researchers are developing small-scale prototypes and working to further improve the perovskite cell's stability and optimize the system.


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New research to improve solar cells

Journal information: Nature Communications

Citation: Researchers efficiently charge a lithium-ion battery with solar cell (2015, August 27) retrieved 16 September 2019 from https://phys.org/news/2015-08-efficiently-lithium-ion-battery-solar-cell.html
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Aug 27, 2015
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Aug 27, 2015
Actually, I find my electric car to be far *more* reliable than ICE cars I've had in the past. No oil changes, fewer moving parts, no engine vibration.

Yes, I'll grant that the benefit is still fairly marginal when you consider end-to-end construction and energy use. In my area, they are a net benefit, but there are some areas where maybe they are not.

But moreover, by creating a market now, economies of scale can help make the overall process more efficient and cheaper in the long run.

Aug 27, 2015
"this is a system that you could have at home to refuel your car "

So, you arrive home just as the sun is going down. How are you going to charge your car ready for the next morning commute?

Aug 27, 2015
Well people back to the paper, charging a battery from a solar cell what a novel idea. Wow, some rocket scientist had the unparalleled idea of putting multiple solar cells in series to make the charging more efficient, will the green breakthroughs ever stop!

The Ministry of Truth never stops issuing green feel good press releases.

Aug 27, 2015
"Well people back to the paper, charging a battery from a solar cell what a novel idea."
-------------------------------------

Would you rather they used coal-fired generators?

I find it interesting that Detroit has set up engineering and design centers in Silicon Valley, where real estate is very expensive. It is where the future is being made, and the future is electric.

Aug 27, 2015
"I find it interesting that Detroit has set up engineering and design centers in Silicon Valley, where real estate is very expensive."

Perhaps they are just trying to avoid the drive by shootings!!!!

Aug 27, 2015
I used to hear folk talk about "back East" like their parents talked about "the old country", . . glad to be gone. I think they are here for the future.

Aug 27, 2015
Would you rather they used coal-fired generators?


How about natural gas, fraction of the CO2 compared to coal, or nuclear?

Aug 27, 2015
wiggers, we are talking about charging individual electric vehicles.

I was being facetious. You too, perhaps.

Aug 27, 2015
In some parts of the country 100% wind generated electricity is available. So it should be possible for many people to charge their electric car with renewable energy exclusively.

https://www.aepen...AF691s1#

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Aug 27, 2015
It's all good and well, but if those cars are so expensive you have to sell your organs to get one, you can add five hundred innovative technologies on it, they won't sell that well. All there is to hope is that people with enough money to buy them WILL buy them. Electric Cars. With or without solar cells. Then, maybe the price will drop, even just slightly, and no longer will we be forced to choose between buying a car or buying a house.

Aug 28, 2015
So, you arrive home just as the sun is going down. How are you going to charge your car ready for the next morning commute?
After USA dollar currency reset your new boss will Be Chinese, so you will be working graveyard

Aug 28, 2015
Why not state the obvious? Electric cars are fine for sort trips, as a second car. Or use a hybrid. But refueling time rules them out as an all rounder.

Aug 28, 2015
A solar cell has a specific output combination of current and voltage which maximizes its energy production, therefore efficiency, and this maximum power point changes with the level of illumination of the cell, and the temperature of the cell. When a battery is connected directly to a PV cell, the system is clamped down to the terminal voltage of the battery, which changes according to the battery's state of charge.

Ideally, the battery's terminal voltage would always match the maximum power point voltage of the PV cell, but this is impossible in practice because both voltages keep shifting around, and the difference in voltage reduces efficiency. In the usual case, you lose 20-30% of the output.

That's why PV systems use what's called Maximum Power Point Tracking which monitor the cell and battery in real time and match the voltages using a DC-DC transformer. This however uses expensive hardware and energy, so it's only economical for larger solar arrays.

Aug 28, 2015
The difficulty with trying to match a battery cell to a PV cell is that you want to get their optimum voltages as close as possible, without ever getting the PV cell's voltage below that of the battery. Otherwise the battery never charges up completely.

That means you need to strike a compromize. The closer you match the battery to the PV cell's maximum output voltage, the more light it needs to begin charging the battery, so while the theoretical efficiency goes up, the practical efficiency goes down because there are fewer hours per day when the cell can actually charge the battery.

Hence why the drop from 12.65% theoretical to 7.8% actual efficiency.

Example graph of the issue:

http://www.homepo...raph.gif

Aug 28, 2015
"It is odd how people don't understand how a major shift happens. It takes time. When the internal combustion engine first came out - and cars started rolling out the factories - consumers were not 'embracing' these new fangled horseless carriages. It took a while."

That's because the early autos were nothing more than unreliable playthings for the rich. When all the problems with renewables have been fixed they too will be embraced by the economic system.

Aug 28, 2015
That's because the early autos were nothing more than unreliable playthings for the rich.


And they could break your arm or shear off you thumb by backfiring while you were trying to hand-crank them. There was a whole step-by-step procedure to do it safely, and if you didn't then you eventually ended up in the hospital.

That's why steam cars and electric runabouts were somewhat popular before they invented the electric starter.

And in general, they were pretty difficult scary things to operate:

https://www.youtu...Qh_Ej_34

Aug 31, 2015
So what?


So that the technology did not and could not reach "critical mass" until most of the practical issues and kinks had been worked out. It had significant treshold issues that prevented widespread use, such as the risk of being maimed.

Same thing for cell phones - etc. etc.


Cellphones too had similiar treshold issues; analog circuit switched cellphone technology could not support more than a few dozen callers per cell because of inefficient radio spectrum use, so it couldn't physically be scaled up to meet demand for the millions until the switch to digital encoding and time division multiplexing. It had nothing to do with gaining enough "critical mass" and popularity - it just couldn't be done in a practical way until the technology caught up.

The main fallacy of the renewables acolyte is the belief that if you just wait, or better yet - force the building of the technology with tax money - all of the problems magically solve themselves.


Aug 31, 2015
Again - so what? Perhaps you have not heard of Tesla.


What does Tesla have to do with anything?

You can look at the past with 20/20 hindsight and see that the solutions have come right on time, but you'd be forgetting those technologies for which the solutions never came and so they don't exist today. Where's your flying car for example?

You were trying to argue that we just have to wait for some "critical mass" to come about, which is being totally blind to the fact that no such critical mass may ever come unless the fundamental issues are solved first.

I compared that to an acolyte because it's being optimistic to the point of dogma.

You are a hater of progress


I do not hate progress. I detest people who pretend progress is where there is none - because that puts the idea into people's minds that all we have to do is wait. It makes people reject real workable solutions to problems because of something that's promised to be "just around the corner".


Aug 31, 2015
You really give yourself away with your language. All technologies have challenges. We are simply watching progress.


Not all technologies progress. For some the challenges become insurmountable, and you can't know which ones because you aren't omniscient. You can't really claim it's "just a matter of time" unless you already have all the solutions ready or so well underway that you might as well call them done.

That's the point.

Why the heck would I hate progress anyways? By definition, progress is making things better. There's nothing to hate with actual progress - what there is to hate is "progress", or things that are objectively worse or don't work.


Aug 31, 2015
You will still be connected to the grid - so can draw some of that cheap wind power that is looking for someone to get a good deal on.


How do you guarantee that there will be wind power on the grid every night?

If you have a 200 mile range car - and less than a 40 mile round trip commute - you can just wait until the weekend to fill her up.


It's gonna be tight to do that. No margin for error whatsoever: no detours and no extra shopping trips.

In some parts of the country 100% wind generated electricity is available. So it should be possible for many people to charge their electric car with renewable energy exclusively.


It's not physically possible to separate power by source in the grid or guarantee wind power when you are using it. Such schemes are simply counting net energy generated, and the actual energy comes from coal/gas/hydro/nuclear etc. which contribute the vast majority of real output.

I.e. it's a scam.

Aug 31, 2015
"Boy - how do you live with yourself - being such a hater."

If there is one statement that epitomizes the entire green community it is that. If one dares to point out the unmentioned shortcomings in a technology or a paper for that matter you become a " HATER"!!!!

Aug 31, 2015
It is time we remind the Deniers and skeptics and goobers they have already lost.

Eikka brings up little irrelevancies as if they were huge problems, and assumes only he is aware of them, the engineers being idiots, I guess. Fact is this is another nail in the well-fastened coffin of coal and nuclear power.

Aug 31, 2015
Great Onions so air pollution due to fossil fuels kills 8 million people a year. Well the cheap food, housing, medicine and transportation that fossils provide saves 100 or even 1000 times that amount each and every year.

Aug 31, 2015
166, maybe you missed the message: We do not need to provide those services with fuel which kills us.


Aug 31, 2015
"We do not need to provide those services with fuel which kills us."

That is where you are 100% wrong. There is no way that TODAY'S renewables can replace fossil period.

Aug 31, 2015
they have already lost.
We do not need to provide those services with fuel which kills us.
Long Live "greenie lie machine"! backed by fossil fuels as baseload.

Aug 31, 2015
Yup, Dirty Fuels are now relegated to backups. Soon, we will not need them.

Who wants to buy power from Vogtle? It is already three times the price of alternative energy,and the costs have not stopped increasing. By the time they are ready to operate, will they be able to do so economically??

Or will they write it off, and hit us taxpayers for the $8,300,000,000 in loans we guaranteed to a corporation? Who said we bail out corporations? I thought we had Capitalism!!

Aug 31, 2015
"That is where you are 100% wrong. There is no way that TODAY'S renewables can replace fossil period."
-----------------------------

The progress used to be poco a poco. But now, it is full speed ahead. Dirty Power is dying. We are doing it today, but market penetration takes a long time, especially in technologies intended to last at least one Human generation.

It is a surprise to everybody it is not going to take that long, the benefits of renewables being so great.

Aug 31, 2015
poco a poco ... the benefits of renewables being so great.
It prevents those filthy birds and bats from breathing out CO2 into the environment by slaughtering them and/or by exiling them from their natural habitats.

Aug 31, 2015
PV systems do not "slaughter birds". They are poisoned by coal emissions and stunted by radioactivity, however.

Aug 31, 2015
Onions when renewables are a realistic solution to our energy needs I promise that you and I will dance the happy dance together. My only real fear is that we will run out of economically viable fossil fuels before that happens.

Aug 31, 2015
Yup, Dirty Fuels are now relegated to backups. Soon, we will not need them.

Who wants to buy power from Vogtle?
Hey I know - why dont you just go and blow it up?

Just the thing a psychopath would do.

Get in your little gyrocopter, take along a few pounds of pop rocks and a few dozen 2 liter cokes, and strafe the site until they agree to shut down.

Why didnt you think of this?

Aug 31, 2015
"My only real fear is that we will run out of economically viable fossil fuels before that happens."
----------------------------------
They are barely economically-viable now, without counting the damage of their "externalities". But don't worry, . . as we transition out of Dirty Fuels, more will be available for you folk.

We will always have some, . . in fact, we're in a glut!

Sep 01, 2015
You don't. However - with a large enough grid, diverse enough power sources, some storage, and some baseload (could be nukes, geothermal, csp) - you do provide a stable grid system.


Build it. And don't call it done before it's done.

We are talking about the development of electric cars (...) Are you really that ignorant?????


No we were not. Tesla (man or company?) had absolutely nothing to do with the "critical mass" argument you were trying to peddle. Stop shifting goalposts.

Boy - how do you live with yourself - being such a hater.


I was simply answering your claim that one can drive a 5-day week 40 miles a day on a 200 mile battery without recharging once. Again you are shifting goalposts.

I am sick of living in a world of haters.


Then stop seeing haters all around you. You are a classical example of cognitive dissonance where faults in yourself are projected out as evil in other people.

Sep 01, 2015
Eikka brings up little irrelevancies as if they were huge problems, and assumes only he is aware of them, the engineers being idiots, I guess. Fact is this is another nail in the well-fastened coffin of coal and nuclear power.


The real engineers do know. They're not idiots.

I'm just pointing out disrepancies and contradictions in your own arguments. These sort of things are not "irrelevancies", they are double-think where you switch between contradicting points and arguments seamlessly as it suits you.

For example, to be consistent with yourself, you should really be disagreeing with greenonions, who is a big grid, big power supporter and rightly admits that the grid isn't ready for renewables, although he still refuses to admit that half the technology to make it so doesn't even exist yet.

(Vogtle) It is already three times the price of alternative energy


A blatant lie. You're still persistently ignoring all the subsidies paid to renewable energy.

Sep 01, 2015
Renewables are currently cost competitive with fossil fuels in many parts of the world - and the cost is dropping fast.


The major disagreement here is in the fact that you systematically ignore the subsidies paid, and their effect on the prices. The prices you're seeing and quoting are arbitrary and cherrypicked.

The whole renewable scheme revolves around the subsidies because it is impossible for wind and solar power to function profitably on the free market. This is aknowledged by politicians and planners the world over - they automatically out-compete themselves out of the free market by the supply not matching the demand, which causes a price crash.

They're not in competition with anything, because they're entirely political entitites which exist only because of the price guarantees, tariffs and tax breaks. They wouldn't and couldn't be built without, and as such the real cost of renewable energy is how much subsidies they are paid, which is A LOT.


Sep 01, 2015
I come to physorg to look for a bit of hope in a f*cked up world. And so much of the comments section is poisoned by the haters - who spend their time making up reasons why things can't be done


I see the problem the other way around.

So many of these forums are infested with starry-eyed dreamers who are willing to gobble up any clickbait and hype, hook line and sinker, just because it gives them unwarranted hope and confirms their faith.

Then they go around preaching how the grand tomorrow is here today if we just keep spending other people's money on building some wind farms or solar panels that make absolutely no difference for the fossil fuel and climate change question and only serve to line up some crony capitalists' pockets with dollar bills.

The cost of making you feel good is the poverty of others who are forced to pay for all of it.

"Let me help so you surely wouldn't drown, said the monkey lifting the fish up a tree."

Sep 01, 2015
My only real fear is that we will run out of economically viable fossil fuels before that happens.

There's probably enough fossil fuels. The thing we will run out of is money if we don't act fast, because at some point - if we continue using fossil fuels at current/predicted rates - we'll spend all our resources on mitigating/repairing/protecting ourselves from damages caused by climate change (water supplies - with possible wars e.g. in the middle east over who gets to take how much water from what river (Jordan/Israel, Syria); combatting mass migration due to sever drought - which is already happening; hardeing ALL coastal cities against rising sea levels and more sever storms - that alone is gonna be a doozy, ... )

Sep 01, 2015
Well - there are plenty of smart people who disagree with you (cleantech article)


This is exactly the kind of "creative interpretation of facts", aka. hype and bullshit I'm talking about.

The paper itself, which the article is based on, talks of the possibility of generating terawatts of power, but that in itself doesn't mean we can -utilize- the power in any meaningful way.

Just as if I were to dump a truckful of bread on your front yard and say "There's your bread for the whole year. Eat up". It's not that simple. For starters, you better have a big walk-in freezer or it's all gonna rot right there.

There's a Grand-Canyon-size leap of faith between saying "Today's solar panels could produce such and so much energy", and, "Today's solar panels can power the world".


Sep 01, 2015
The thing we will run out of is money


Exactly, and the more we keep subsidizing wind and solar with no coherent plan of integration and no technology to do so, the faster we run out of money and resources to do anything about it.

If instead we put all the billons and billions per year into basic research and energy storage technology, we'll create a market where these renewable energies can operate profitably without government intervention and the associated corruption and cronyism, and at that point we'll be able to reach the "critical mass" where fossil fuels are no longer needed.

But failling that, failing massive investment into energy storage research, or if we hit some fundamental roadblock, the only option left is to just build more nuclear power and fast.

Sep 01, 2015
Exactly, and the more we keep subsidizing wind and solar with no coherent plan of integration and no technology to do so, the faster we run out of money and resources to do anything about it.

That statement makes no sense.

Fossil fuels/nuclear are a cocaine effect. The more we use them the more expensive they get (limited supply, compounding waste problem) and the more money we need to pump in to mitigate damage they cause until we run out of both (fuel sourec and money): This is just a planned disaster (read: stupid, because we can see the breakdown point coming from a long way off)

Renewables are a one-time investment with none of the drawbacks of the above (and with the added benefit of allowing us to live in a cleaner environment).

By any calculation (health, economic, political, social ...even in terms of job security) you care to make renewables win hands down.

Sep 01, 2015
"Exactly, and the more we keep subsidizing wind and solar with no coherent plan of integration and no technology to do so, the faster we run out of money and resources to do anything about it."
-----------------------------------

Stop the panic. Who does that? Why would you want to think they actually do as such? I think you got yourself into an irrational fit.

Better worry about finding a way to hold the nasty nuke waste than lose sleep over wind turbines. And this thread regards PV and storage, not wind.

Sep 01, 2015
I think Eikka is trying to "win" a debate. We are more concerned with better power sources.

Sep 01, 2015
..renewables (see Costa Rica)
Costa Rica: fossil fuel(9.28%) hydro(80.62%) other(10.1%)
Excluding hydro, renewable energy has proven to be unreliable.
https://en.wikipe...sta_Rica
Nuclear is our best carbon-free option.

Sep 01, 2015
Better worry about finding a way to hold the nasty nuke waste than lose sleep over wind turbines
Stop the panic. Who does that? Why would you want to think they actually do as such? I think you got yourself into an irrational fit.

Sep 01, 2015
something up to date...http://thinkprogr...ewables/
"Hydroelectric plants supply the bulk of that electricity — 68 percent — while geothermal plants provide about 15 percent, wind power provides 5 percent, and solar and biomass also contribute slightly to the country's energy mix."

Hydro impacts: "dislocation of people living where the reservoirs are planned, release of significant amounts of carbon dioxide at construction and flooding of the reservoir, disruption of aquatic ecosystems and birdlife, adverse impacts on the river environment, potential risks of sabotage and terrorism, and in rare cases catastrophic failure of the dam wall."
https://en.wikipe...ctricity

death/TWh: Solar 0.44 , Wind 0.15, Hydro 0.10, Nuclear 0.04
Nuclear is safer than solar, wind and hydro.
http://scienceblo...tricity/

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