Self-Healing Lithium-Ion Batteries

Researchers at the University of Illinois have found a way to apply self-healing technology to lithium-ion batteries to make them more reliable and last longer.

The group developed a battery that uses a silicon nanoparticle composite material on the negatively charged side of the battery and a novel way to hold the composite together – a known problem with batteries that contain silicon.

Materials science and engineering professor Nancy Sottos and aerospace engineering professor Scott White led the study published in the journal Advanced Energy Materials.

“This work is particularly new to self-healing materials research because it is applied to materials that store energy,” White said. “It’s a different type of objective altogether. Instead of recovering structural performance, we’re healing the ability to store energy.”

The negatively charged electrode, or anode, inside the lithium-ion batteries that power our portable devices and electric cars are typically made of a graphite particle composite. These batteries work well, but it takes a long time for them to power up, and over time, the charge does not last as long as it did when the batteries were new.

Silicon has such a high capacity, and with that high capacity, you get more energy out of your battery, except it also undergoes a huge volume expansion as it cycles and self-pulverizes,” Sottos explained.

Past research found that battery anodes made from nanosized silicon particles are less likely to break down, but suffer from other problems.

You go through the charge-discharge cycle once, twice, three times, and eventually you lose capacity because the silicon particles start to break away from the binder,” White said.

To combat this problem, the group further refined the silicon anode by giving it the ability to fix itself on the fly. This self-healing happens through a reversible chemical bond at the interface between the silicon nanoparticles and polymer binder.

Source: https://news.illinois.edu/

Bubbles And The Future Of Electric Cars

With about three times the energy capacity by weight of today’s lithium-ion batteries, lithium-air batteries could one day enable electric cars to drive farther on a single charge. But the technology has several holdups, including losing energy as it stores and releases its charge. If researchers could better understand the basic reactions that occur as the battery charges and discharges electricity, the battery’s performance could be improved. One reaction that hasn’t been fully explained is how oxygen blows bubbles inside a lithium-air battery when it discharges. The bubbles expand the battery and create wear and tear that can cause it to fail.

A paper in Nature Nanotechnology provides the first step-by-step explanation of how lithium-air batteries form bubbles. The research was aided by a first-of-a-kind video that shows bubbles inflating and later deflating inside a nanobattery. Researchers had previously only seen the bubbles, but not how they were created.

If we fully understand the bubble formation process, we could build better lithium-air batteries that create fewer bubbles,” noted the paper’s corresponding author, Chongmin Wang, of the Department of Energy’s Pacific Northwest National Laboratory (PNNL). “The result could be more compact and stable batteries that hold onto their charge longer.”

Wang works out of EMSL, the Environmental Molecular Sciences Laboratory, a DOE Office of Science user facility located at PNNL. His co-authors include other PNNL staff and a researcher from Tianjin Polytechnic University in China.

The team’s unique video may be a silent black-and-white film, but it provides plenty of action. Popping out from the battery’s flat surface is a grey bubble that grows bigger and bigger. Later, the bubble deflates, the top turning inside of itself until only a scrunched-up shell is left behind.

The popcorn-worthy flick was captured with an in-situ environmental transmission electron microscope at EMSL. Wang and his colleagues built their tiny battery inside the microscope’s column. This enabled them to watch as the battery charged and discharged inside.

Video evidence led the team to propose that as the battery discharges, a sphere of lithium superoxide jets out from the battery’s positive electrode and becomes coated with lithium oxide. The sphere’s superoxide interior then goes through a chemical reaction that forms lithium peroxide and oxygen. Oxygen gas is released and inflates the bubble. When the battery charges, lithium peroxide decomposes, and leaves the former bubble to look like a deflated balloon.

Source: http://www.pnnl.gov/

 

Electric Car: Graphene Is The Next Revolution

Henrik Fisker, the famed automotive designer known for his work on iconic vehicles such as the Aston Martin DB9, the Aston Martin V8 Vantage and the BMW Z8, did not do well in an electric car venture that he launched in 2007. Fisker Automotive was a rival to Tesla Motors in the early days of the electric car industry, but it was not able to deliver its promised vehicles and had to declare bankruptcy in 2013. However, it seems that Fisker has not pushed electric cars out of his mind, as it was recently reported that he is returning to the electric vehicle scene with a new company named Fisker Inc. that will be taking form next year.

With rival Tesla Motors now the perceived leader in the industry, Fisker Inc. is looking to make a splash. It seems that the new company would be able to do so, as Fisker revealed that instead of the traditional lithium-ion batteries, Fisker Inc. vehicles will be powered by a new kind of battery known as graphene supercapacitors.

graphene-electric-car

It was earlier reported that the luxury electric car that Fisker Inc. is working on will have a full-charge range that will reach over 400 miles, which is significant because the longest range that Tesla Motors offers through its vehicles is 315 miles on the high-end version of the Model S. The 400-mile range is said to be made possible by the usage of graphene in electric car batteries, with the technology being referred to by Fisker as the “next big step” in the industry.

According to Michigan Technological University assistant professor Lucia Gauchia, graphene has a higher electron mobility and presents a higher active surface, which are characteristics that lead to faster charging times and expanded energy storage, respectively, when used for batteries.

Graphene, however, has so far been associated with high production costs. Fisker is looking to solve that problem and mass produce graphene through a machine that his battery division, named Fisker Nanotech, is looking to have patented. Through the machine, 1,000 kilograms of graphene can be produced at a cost of just 10 cents per gram.

Our battery technology is so much better than anything out there,” Fisker said, amid the many improvements that his company has made on the material’s application to electric car batteries.

Fisker also said that the first Fisker Inc. electric car is being planned to be unveiled in the second half of next year. The luxury electric vehicle will only have limited production, and will be in the price range of the higher-end models of the Model S. However, Fisker said that he will then be producing consumer-friendly electric vehicles that will be even cheaper compared with the Tesla Model 3 and the Chevrolet Bolt, following the footsteps of its rival.

Source: http://www.techtimes.com/

Electric Train: Bye Bye Diesel, Hello Pure Air !

The French company Alstom has presented its zero-emission train at InnoTrans, the railway industry’s largest trade fair (Berlin September 2016). Despite numerous electrification projects in several countries, a significant part of Europe’s rail network will remain non-electrified in the long term. In many countries, the number of diesel trains in circulation is still high – more than 4,000 cars in Germany, for instance.

Coradia iLint from Alstom is a new CO2-emission-free regional train and alternative to diesel power. It is powered by a hydrogen fuel cell, its only emission being steam and condensed water while operating with a low level of noise. Alstom is among the first railway manufacturers in the world to develop a passenger train based on such a technology. To make the deployment of the Coradia iLint as simple as possible for operators, Alstom offers a complete package, consisting of the train and maintenance, as well as also the whole hydrogen infrastructure out of one hand thanks to help from partners.

Alstom expects to sign a firm order for a production build of hydrogen fuel cell powered multiple-units by the end of the year, Coradia LINT Product Manager Stefan Schrank told Railway Gazette on September 20.

The expected initial firm order would cover units for service in Nordrhein-Westfalen. Alstom has already signed letters of intent with four German Länder covering a total of 60 trainsets, and anticipates firm orders for between 40 and 70 units by the end of 2017. Schrank was speaking at InnoTrans following the unveiling of the first of two pre-production iLINT fuel cell multiple-units which are to be tested on regional services around Hannover under an agreement with the Land of Niedersachsen. The two pre-production units are owned by Alstom, which plans to conduct testing throughout 2017, including at the Velim test circuit. Type approval from Germany’s Federal Railway Office is expected by the end of 2017, enabling the start of trial passenger running around Hannover in late 2017 or early 2018.

alstom-hydrogen-electric-train

The fuel cell trainsets have the same bodies, bogies and drive equipment as the conventional diesels, and the two units will directly replace two diesel units to provide a real-world comparison of performance.

The hydrogen tanks and fuel cells are mounted on the car roofs, with the tanks carrying 94 kg of hydrogen per car, enough for around one day or 700 km of operation. The fuel cells were supplied by Hydrogenics, after Alstom took a decision to partner with an experienced specialist rather than develop its own technology. The fuel cells are linked to lithium ion batteries from Akasol.

Alstom anticipates that operating costs will be comparable to diesel units. The environmental footprint of the trainsets will depend on how the hydrogen is produced; under Germany’s current electricity generating mix and electrolysis produces an unfavourable comparison to diesel, but the generating mix predicted for 2020 would make the hydrogen greener, Schrank said.

He sees a bright future for fuel cells, which he believes have now reached a comparable level of development to diesel engines 100 years ago.

Source: http://www.railwaygazette.com/

How To Increase By Six Times The Capacity Of Lithium-Ion Batteries

The capacity of lithium-ion batteries might be increased by six times by using anodes made of silicon instead of graphite. A team from the Helmholtz-Zentrum Berlin (HZB) Institute of Soft Matter and Functional Materials has observed for the first time in detail how lithium ions migrate into thin films of silicon. It was shown that extremely thin layers of silicon would be sufficient to achieve the maximal load of lithium.

The team was able to show through neutron measurements made at the Institut Laue-Langevin in Grenoble, France, that lithium ions do not penetrate deeply into the silicon. During the charge cycle, a 20-nm anode layer develops containing an extremely high proportion of lithium. This means extremely thin layers of silicon would be sufficient to achieve the maximal load of lithium.
lithium-ion battery

Lithium-ion batteries provide laptops, smart phones, and tablet computers with reliable energy. However, electric vehicles have not gotten as far along with conventional lithium-ion batteries. This is due to currently utilised electrode materials such as graphite only being able to stably adsorb a limited number of lithium ions, restricting the capacity of these batteries. Semiconductor materials like silicon are therefore receiving attention as alternative electrodes for lithium batteries. Bulk silicon is able to absorb enormous quantities of lithium. However, the migration of the lithium ions destroys the crystal structure of silicon. This can swell the volume by a factor of three, which leads to major mechanical stresses. Now a team from the HZB Institute for Soft Matter and Functional Materials headed by Prof. Matthias Ballauff has directly observed for the first time a lithium-silicon half-cell during its charging and discharge cycles. “We were able to precisely track where the lithium ions adsorb in the silicon electrode using neutron reflectometry methods, and also how fast they were moving”, comments Dr. Beatrix-Kamelia Seidlhofer, who carried out the experiments using the neutron source located at the Institute Laue-Langevin.

She discovered two different zones during her investigations. Near the boundary to the electrolytes, a roughly 20-nm layer formed having extremely high lithium content: 25 lithium atoms were lodged among 10 silicon atoms. A second adjacent layer contained only one lithium atom for ten silicon atoms. Both layers together are less than 100 nm thick after the second charging cycle.

After discharge, about one lithium ion per silicon node in the electrode remained in the silicon boundary layer exposed to the electrolytes. Seidlhofer calculates from this that the theoretical maximum capacity of these types of silicon-lithium batteries lies at about 2300 mAh/g. This is more than six times the theoretical maximum attainable capacity for a lithium-ion battery constructed with graphite (372 mAh/g).

The results ar published in the journal ACSnano (DOI: 10.1021/acsnano.6b02032).

Source: https://www.helmholtz-berlin.de/

3D Nano-structured Porous Electrodes Boost Batteries

Battery-life is increasingly the sticking point of technological progress.The latest electric vehicles can practically drive themselve, but only for so long. Outback energy woes look like they could be solved by solar and home energy storage, if the available batteries can be improved. And what about the Pokemon GO players, cutting hunting trips short due to the battery-sapping requirements of the app?

The solution could come from Sunshine Coast nanotechnology company Nano Nouvelle, which is developing a three-dimensional, nano-structured, porous electrode that it says will help overcome the limitations of today’s batteries.The company announced today that its ‘Nanodenanomaterials were being tested and trialled by two unnamed US specialist battery manufacturers.

stephanie-moroz

CEO Stephanie Moroz said she hoped the profile of the trials would lead to wider adoption.“As Tesla proved with its Roadster EV sportscar, this sort of low-volume, high-margin starting point can provide a high visibility platform to demonstrate the benefits of innovative technology, which can accelerate its adoption by mass market manufacturers.”

Nano Nouvelle’s core technology, the Nanode uses tin as the electrode material, which has a much higher energy density than the current graphite technology. However, until now tin’s commercial use had been limited due to its tendency to swell during charging and subsequently lose energy.

This issue is overcome by the Nanode’s structure, made up of thin films of active material spread over a 3D and porous network of fibres, rather than stacked on a flat copper foil.

This enables the electrode structure to deal with the volume expansion of the tin while retaining dimensional stability at the electrode level. The result is batteries that can store the same amount of energy in a smaller volume, compared to commercial lithium ion batteries.

Moroz said she believed the nanotechnology could be easily incorporated into the existing battery manufacturing process. Moroz said she believed the nanotechnology could be easily incorporated into the existing battery manufacturing process.

We’re looking to make it plug and play for battery manufacturers,” she said.

Source: http://www.cio.com.au/

Electric Cars That Eat CO2

An interdisciplinary team of scientists has worked out a way to make electric vehicles that only are not only carbon neutral but carbon negative, capable of actually reducing the amount of atmospheric carbon dioxide as they operate.

They have done so by demonstrating how the graphite electrodes used in the lithium-ion batteries that power electric automobiles can be replaced with carbon material recovered from the atmosphere. The unusual pairing of carbon dioxide conversion and advanced battery technology is the result of a collaboration between the laboratory of Assistant Professor of Mechanical Engineering Cary Pint at Vanderbilt University and Professor of Chemistry Stuart Licht at George Washington University. The team adapted a solar-powered process that converts carbon dioxide into carbon so that it produces carbon nanotubes and demonstrated that the nanotubes can be incorporated into both lithium-ion batteries like those used in electric vehicles and electronic devices and low-cost sodium-ion batteries under development for large-scale applications, such as the electric grid.

Tesla Model 3

This approach not only produces better batteries but it also establishes a value for carbon dioxide recovered from the atmosphere that is associated with the end-user battery cost unlike most efforts to reuse CO2 that are aimed at low-valued fuels, like methanol, that cannot justify the cost required to produce them,” said Pint. “Our climate-change solution is two fold: (1) to transform the greenhouse gas carbon dioxide into valuable products and (2) to provide greenhouse gas emission-free alternatives to today’s industrial and transportation fossil fuel processes,” adds Licht. “In addition to better batteries other applications for the carbon nanotubes include carbon composites for strong, lightweight construction materials, sports equipment and car, truck and airplane bodies.

The project builds upon a solar thermal electrochemical process (STEP) that can create carbon nanofibers from ambient carbon dioxide developed by the Licht group and described in the journal Nano Letters last August. STEP uses solar energy to provide both the electrical and thermal energy necessary to break down carbon dioxide into carbon and oxygen and to produce carbon nanotubes that are stable, flexible, conductive and stronger than steel.

The recipe for converting carbon dioxide gas into batteries is described in the paper titled “Carbon Nanotubes Produced from Ambient Carbon Dioxide for Environmentally Sustainable Lithium-Ion and Sodium-Ion Battery Anodes” published online on Mar. 2 by the journal ACS Central Science.

Source: http://news.vanderbilt.edu/

Candle Soot Powers Lithium Ion Battery

A new study reveals that carbon from candle soot could be used to power the kind of lithium ion battery in plug-in hybrid electric cars. Researchers from the Indian Institute of Technology in Hyderabad, India claim that their findings could open up possibilities for using carbon in more powerful batteries, which could drive down the costs of portable power.

Lithium ion batteries are used to power a wide range of devices, including smartphones, digital cameras, electric cars and even aircraft. The batteries produce current through two electrically charged materials suspended in a liquid. Carbon, while used as one of the materials in smaller batteries, is considered unsuitable for bigger and more powerful batteries because of its structure, which cannot produce the required current density.

In the new study, published in the journal Electrochimica Acta, the researchers found that because of the shape and configuration of the tiny carbon nanoparticles, the carbon in candle soot could be used in bigger batteries. The team also said that their research introduces a more scalable approach to making batteries because the soot could be produced quickly and easily.

soot

If you put water droplet on candle soot it rolls off – that’s an observation that’s been made in the last few years. The material candle soot is made of, carbon, also has electric potential. So why not use it as an electrode? We looked into it and saw it also shows some exceptional electrochemical properties, so we decided to test it further,” said Dr Chandra Sharma, one of the study’s authors.

Using a technique called cyclic charge-discharge, or CCD, the researchers analysed the effectiveness of soot as a conducting material to use in a battery. The technique shows how powerful the battery is based on the rate of charge or discharge: the higher the rate, the more powerful the battery. According to the study’s results, the candle soot carbon performed better at higher rates.

Sharma said the technology is not only efficient and cost-effective but also scalable, which could make battery production cheaper. One hybrid car would need approximately 10 kilograms of carbon soot, which would be deposited in about an hour using candles, Sharma explained.

Source: http://www.sciencedirect.com/
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http://www.ibtimes.com.au/

How To Boost Electric Vehicle Batteries

Researchers from the Professor Mihri Ozkan lab at the University of California, Riverside’s Bourns College of Engineering have developed a novel paper-like material for lithium-ion batteries. It has the potential to boost by several times the specific energy, or amount of energy that can be delivered per unit weight of the battery.
This paper-like material is composed of sponge-like silicon nanofibers more than 100 times thinner than human hair. It could be used in batteries for electric vehicles and personal electronics.

electric carThe problem with silicon is that is suffers from significant volume expansion, which can quickly degrade the battery. The silicon nanofiber structure created in the Ozkan’s labs circumvents this issue and allows the battery to be cycled hundreds of times without significant degradation. This technology also solves a problem that has plagued free-standing, or binderless, electrodes for years: scalability. Free-standing materials grown using chemical vapor deposition, such as carbon nanotubes or silicon nanowires, can only be produced in very small quantities (micrograms). However, the team was able to produce several grams of silicon nanofibers at a time even at the lab scale.

The nanofibers were produced using a technique known as electrospinning, whereby 20,000 to 40,000 volts are applied between a rotating drum and a nozzle, which emits a solution composed mainly of tetraethyl orthosilicate (TEOS), a chemical compound frequently used in the semiconductor industry. The nanofibers are then exposed to magnesium vapor to produce the sponge-like silicon fiber structure.

The findings were just published in the journal Nature Scientific Reports.
Source: http://www.mse.ucr.edu/

Li-Ion Batteries Mimick Shells To Last Longer

Scientists are using biology to improve the properties of lithium ion batteries. Researchers at the University of Maryland, Baltimore County (UMBC) have isolated a peptide, a type of biological molecule, which binds strongly to lithium manganese nickel oxide (LMNO), a material that can be used to make the cathode in high performance batteries. The peptide can latch onto nanosized particles of LMNO and connect them to conductive components of a battery electrode, improving the potential power and stability of the electrode.

snail_shell_battery-3
Biology provides several tools for us to solve important problems,” said Evgenia Barannikova, a graduate student at UMBC. Barannikova works in the lab of Mark Allen and studies how biological molecules in general can improve the properties of inorganic materials in batteries.

Biology provides several tools for us to solve important problems,” said Evgenia Barannikova, a graduate student at UMBC. Barannikova works in the lab of Mark Allen and studies how biological molecules in general can improve the properties of inorganic materials in batteries.
By providing a new nanoscale architecture for lithium-ion batteries, the researchers say that the approach could improve the power and cycling stability of lithium-ion batteries.
The researchers will present their results at the 59th annual meeting of the Biophysical Society, held Feb. 7-11 in Baltimore, Maryland.
Source: http://phys.org/

Lithium-Ion Batteries That Last 3 Times Longer

Using a material found in Silly Putty and surgical tubing, a group of researchers at the University of California, Riverside Bourns College of Engineering have developed a new way to make lithium-ion batteries that will last three times longer between charges compared to the current industry standard.
The team created silicon dioxide (SiO2) nanotube anodes for lithium-ion batteries and found they had over three times as much energy storage capacity as the carbon-based anodes currently being used. This has significant implications for industries including electronics and electric vehicles, which are always trying to squeeze longer discharges out of batteries.

We are taking the same material used in kids’ toys and medical devices and even fast food and using it to create next generation battery materials,” said Zachary Favors, the lead author of a just-published paper online in the journal Nature Scientific Reports.

Source: http://ucrtoday.ucr.edu/

Hydrogen To Replace Lithium-Ion Battery

The novel concept developed by researchers at RMIT University – Australia -advances the potential for hydrogen to replace lithium as an energy source in battery-powered devices.

The proton flow battery concept eliminates the need for the production, storage and recovery of hydrogen gas, which currently limit the efficiency of conventional hydrogen-based electrical energy storage systems.

Lead researcher Associate Professor John Andrews, from RMIT‘s School of Aerospace, Mechanical and Manufacturing Engineering, said the novel concept combined the best aspects of hydrogen fuel cells and battery-based electrical power.

As only an inflow of water is needed in charge mode – and air in discharge mode – we have called our new system the ‘proton flow battery,” Associate Professor Andrews said.

Powering batteries with protons has the potential to be a much more economical device than using lithium ions, which have to be produced from relatively scarce mineral, brine or clay resources”. “Hydrogen has great potential as a clean power source and this research advances the possibilities for its widespread use in a range of applications – from consumer electronic devices to large electricity grid storage and electric vehicles“, he added.

Source: http://www.rmit.edu.au