MIT: New type of electrolyte could enhance supercapacitor performance

Large anions with long tails (blue) in ionic liquids can make them self-assemble into sandwich-like bilayer structures on electrode surfaces. Ionic liquids with such structures have much improved energy storage capabilities.

Image: Xianwen Mao, MIT

Novel class of “ionic liquids” may store more energy than conventional electrolytes — with less risk of catching fire.

Supercapacitors, electrical devices that store and release energy, need a layer of electrolyte — an electrically conductive material that can be solid, liquid, or somewhere in between. Now, researchers at MIT and several other institutions have developed a novel class of liquids that may open up new possibilities for improving the efficiency and stability of such devices while reducing their flammability.

“This proof-of-concept work represents a new paradigm for electrochemical energy storage,” the researchers say in their paper describing the finding, which appears today in the journal Nature Materials.

For decades, researchers have been aware of a class of materials known as ionic liquids — essentially, liquid salts — but this team has now added to these liquids a compound that is similar to a surfactant, like those used to disperse oil spills. With the addition of this material, the ionic liquids “have very new and strange properties,” including becoming highly viscous, says MIT postdoc Xianwen Mao PhD ’14, the lead author of the paper.

“It’s hard to imagine that this viscous liquid could be used for energy storage,” Mao says, “but what we find is that once we raise the temperature, it can store more energy, and more than many other electrolytes.”

That’s not entirely surprising, he says, since with other ionic liquids, as temperature increases, “the viscosity decreases and the energy-storage capacity increases.”

But in this case, although the viscosity stays higher than that of other known electrolytes, the capacity increases very quickly with increasing temperature. That ends up giving the material an overall energy density — a measure of its ability to store electricity in a given volume — that exceeds those of many conventional electrolytes, and with greater stability and safety.

The key to its effectiveness is the way the molecules within the liquid automatically line themselves up, ending up in a layered configuration on the metal electrode surface. The molecules, which have a kind of tail on one end, line up with the heads facing outward toward the electrode or away from it, and the tails all cluster in the middle, forming a kind of sandwich. This is described as a self-assembled nanostructure.

“The reason why it’s behaving so differently” from conventional electrolytes is because of the way the molecules intrinsically assemble themselves into an ordered, layered structure where they come in contact with another material, such as the electrode inside a supercapacitor, says T. Alan Hatton, a professor of chemical engineering at MIT and the paper’s senior author. “It forms a very interesting, sandwich-like, double-layer structure.”

This highly ordered structure helps to prevent a phenomenon called “overscreening” that can occur with other ionic liquids, in which the first layer of ions (electrically charged atoms or molecules) that collect on an electrode surface contains more ions than there are corresponding charges on the surface.

This can cause a more scattered distribution of ions, or a thicker ion multilayer, and thus a loss of efficiency in energy storage; “whereas with our case, because of the way everything is structured, charges are concentrated within the surface layer,” Hatton says.

The new class of materials, which the researchers call SAILs, for surface-active ionic liquids, could have a variety of applications for high-temperature energy storage, for example for use in hot environments such as in oil drilling or in chemical plants, according to Mao. “Our electrolyte is very safe at high temperatures, and even performs better,” he says. In contrast, some electrolytes used in lithium-ion batteries are quite flammable.

The material could help to improve performance of supercapacitors, Mao says. Such devices can be used to store electrical charge and are sometimes used to supplement battery systems in electric vehicles to provide an extra boost of power.

Using the new material instead of a conventional electrolyte in a supercapacitor could increase its energy density by a factor of four or five, Mao says. Using the new electrolyte, future supercapacitors may even be able to store more energy than batteries, he says, potentially even replacing batteries in applications such as electric vehicles, personal electronics, or grid-level energy storage facilities.

The material could also be useful for a variety of emerging separation processes, Mao says. “A lot of newly developed separation processes require electrical control,” in various chemical processing and refining applications and in carbon dioxide capture, for example, as well as resource recovery from waste streams. These ionic liquids, being highly conductive, could be well-suited to many such applications, he says.

The material they initially developed is just an example of a variety of possible SAIL compounds. “The possibilities are almost unlimited,” Mao says. The team will continue to work on different variations and on optimizing its parameters for particular uses. “It might take a few months or years,” he says, “but working on a new class of materials is very exciting to do. There are many possibilities for further optimization.”

The research team included Paul Brown, Yinying Ren, Agilio Padua, and Margarida Costa Gomes at MIT; Ctirad Cervinka at École Normale Supérieure de Lyon, in France; Gavin Hazell and Julian Eastoe at the University of Bristol, in the U.K.; Hua Li and Rob Atkin at the University of Western Australia; and Isabelle Grillo at the Institut Max-von-Laue-Paul-Langevin in Grenoble, France. The researchers dedicate their paper to the memory of Grillo, who recently passed away.

“It is a very exciting result that surface-active ionic liquids (SAILs) with amphiphilic structures can self-assemble on electrode surfaces and enhance charge storage performance at electrified surfaces,” says Yi Cui, a professor of materials science and engineering at Stanford University, who was not associated with this research. “The authors have studied and understood the mechanism. The work here might have a great impact on the design of high energy density supercapacitors, and could also help improve battery performance,” he says.

Nicholas Abbott, the Tisch University Professor at Cornell University, who also was not involved in this work, says “The paper describes a very clever advance in interfacial charge storage, elegantly demonstrating how knowledge of molecular self-assembly at interfaces can be leveraged to address a contemporary technological challenge.”

The work was supported by the MIT Energy Initiative, an MIT Skoltech fellowship, and the Czech Science Foundation.

Why Did Elon Musk Spend $218 Million (in stock) on an Ultracapacitor Company? The Answer may be in ‘Dry Electrode Technology’

          Does Tesla want ultracapacitors? Or dry electrode technology?

Earlier this month, Tesla announced plans to acquire Maxwell Technologies, an established, 380-employee ultracapacitor and storage materials firm for $218 million in an all-stock deal. It’s easy for a transaction of this sort to get lost in the Tesla media cycle.

 

Elon Musk was once intent on studying ultracapacitors at Stanford University, long before Tesla was even a gleam in his eye. Apparently, Musk is still charged up on the technology.

Maxwell’s total revenue was $91.6 million in the first nine months of 2018, with losses of $30.2 million. Revenue in 2017 was $130.3 million with losses of $43.1 million.

So why is Tesla paying above book value (but still not enough, according to some investors) for a money-losing firm (here’s Maxwell’s SEC filing)?

Does Tesla want ultracapacitors?

Maxwell’s core business is ultracapacitors, the wide-temperature-range, high-power-density energy storage component that can rapidly charge and discharge. Also known as supercaps or electronic double layer capacitors, ultracapacitors are geared for high-power and high-cycle applications.

Batteries use a chemical process to store energy, while ultracapacitors store a static electric charge — physically separating positive and negative charges.

Maxwell’s ultracaps deliver peak power as well as regenerative braking, voltage stabilization, backup power and hybrid stop/start. Ultracaps are also used to power the pitch control adjustment in wind turbines during sudden wind speed changes, since replacing batteries at 500 feet above the ground is tricky.

In a previous interview, Maxwell’s CEO estimated that there is $5,000 worth of ultracaps in the typical wind turbine and $15,000 per electric bus. Maxwell declined to respond to GTM to update those figures.

Or dry electrode technology?

But Maxwell’s allure might not be its ultracapacitors — it might be the dry electrode technology developed by Maxwell that really intrigues Elon Musk.

The “dry” in “dry electrode technology” refers to an ultracapacitor manufacturing process that Maxwell claims can improve battery costs, performance and lifetime across a variety of lithium-ion battery chemistries. 

Maxwell states, in a release, that its dry electrode manufacturing technology, historically used to make ultracapacitors, is “a breakthrough technology that can be applied to the manufacturing of batteries.”

A white paper from Maxwell claims that its dry battery electrode (DBE) coating technology can be used with “classical and advanced” lithium-ion battery chemistries, but “unlike conventional slurry cast wet coated electrode, Maxwell’s DBE produces a thick electrode that allows for high energy density cells with better discharge rate capability than those of a wet coated electrode.” (Right: Passive dry electrode schematic)

A presentation from the company claims it has “demonstrated” an energy density of greater than 300 watt-hours per kilogram and has “identified” a path to greater than 500 watt-hours per kilogram. Maxwell claims to have used the process with a number of available anode materials.

A battery expert colleague notes that solvent-free electrode manufacturing “might be worth $200 million” if Maxwell “has really eliminated the toxic solvent without compromising on performance.” Maxwell’s patent filings indicate that work is being done to eliminate solvent usage in both dry-processing and melt-processing of binders.

Other ultracap suppliers include Tokin, Seiko, Eaton, CAP-XX, LS Ultracapacitor, Ioxus and Skeleton.

This deal was Tesla’s fifth acquisition since its founding; the others being manufacturing-automation firm Perbix, SolarCity, Riviera Tool and Grohmann Engineering.

During Maxwell’s third-quarter 2018 conference call, CEO Franz Fink noted that its dry electrode business was looking for a partner to provide “significant financial support” and expertise in EVs or energy storage systems. 

If this deal goes through in the coming quarters, Maxwell’s CEO will have gotten his wish.

Story from GTM (GreenTechMedia) – Eric Wescoff

What’s Next: Beyond the lithium-ion battery

Drive for innovation: Electric vehicles are a major target for R&D on novel battery materials. (Image courtesy: imec)

31 Oct 2018

Note to Readers: This article first appeared in the 2018 Physics World Focus on Energy Technologies Engineering a sustainable, electrified future means developing battery materials with properties that surpass those found in current technologies.

The batteries we depend on for our mobile phones and computers are based on a technology that is more than a quarter-century old. Rechargeable lithium-ion (Li-ion) batteries were first introduced in 1991, and their appearance heralded a revolution in consumer electronics. From then on, we could pack enough energy in a small volume to start engineering a whole panoply of portable electronic devices – devices that have given us much more flexibility and comfort in our lives and jobs.

In recent years, Li-ion batteries have also become a staple solution in efforts to solve the interlinked conundrums of climate change and renewable energy. Increasingly, they are being used to power electric vehicles and as the principal components of home-based devices that store energy generated from renewable sources, helping to balance an increasingly diverse and smart electrical grid. The technology has improved too: over the past two and a half decades, battery experts have succeeded in making Li-ion batteries 5–10% more efficient each year, just by further optimizing the existing architecture.

Ultimately, though, getting from where we are now to a truly carbon-free economy will require better-performing batteries than today’s (or even tomorrow’s) Li-ion technology can deliver. In electric vehicles, for example, a key consideration is for batteries to be as small and lightweight as possible.

 

Achieving that goal calls for energy densities that are much higher than the 300 Wh/kg and 800 Wh/L which are seen as the practical limits for today’s Li-ion technology.

Another issue holding back the adoption of electric vehicles is cost, which is currently still around 300–200 $/kWh, although that is widely projected to go below 100 $/kWh by 2025 or even earlier. The time required to recharge a battery pack – still in the range of a few hours – will also have to come down, and as batteries move into economically critical applications such as grid storage and grid balancing, very long lifetimes (a decade or more) will become a key consideration too.

There is still some room left to improve existing Li-ion technology, but not enough to meet future requirements. Instead, the process of battery innovation needs a step change: materials-science breakthroughs, new electrode chemistries and architectures that have much higher energy densities, new electrolytes that can deliver the necessary high conductivity – all in a battery that remains safe and is long-lasting as well as economical and sustainable to produce.

Lithium magic

To appreciate why this is such a challenge, it helps to understand the basic architecture of existing batteries. Rechargeable Li-ion batteries are made up of one or more cells, each of which is a small chemical factory essentially consisting of two electrodes with an electrolyte in between. When the electrodes are connected (for example with a wire via a lamp), an electrochemical process begins. In the anode, electrons and lithium ions are separated, and the electrons buzz through the wire and light up the lamp. Meanwhile, the positively-charged lithium ions move through the electrolyte to the cathode. There, electrons and Li-ions combine again, but in a lower energy state than before.

The beauty of rechargeable batteries is that these processes can be reversed, returning lithium ions to the anode and restoring the energy states and the original difference in electrical potential between the electrodes. Lithium ions are well suited for this task. Lithium is not only the lightest metal in the periodic table, but also the most reactive and will most easily part with its electrons. It has been chosen as the basis for rechargeable batteries precisely because it can do the most work with the least mass and the fewest chemical complications. More specifically, in batteries using lithium, it is possible to make the electric potential difference between anodes and cathodes higher than is possible with other materials.

Solid benefits: The solid, nanoporous electrolyte material developed at imec. (Image courtesy: imec)

To date, therefore, the main challenge for battery scientists has been to find chemical compositions of electrodes and electrolyte that will let the lithium ions do their magic in the best possible way: electrodes that can pack in as many lithium ions as possible while setting up as high an electrical potential difference as possible; and an electrolyte that lets lithium ions flow as quickly as possible back and forth between the anode and cathode.

Seeking a solid electrolyte

The electrolyte in most batteries is a liquid. This allows the electrolyte not only to fill the space between the electrodes but also to soak them, completely filling all voids and spaces and providing as much contact as possible between the electrodes and the electrolyte. To complete the picture, a porous membrane is added between the electrodes. This inhibits electrical contact between the electrodes and prevents finger like outgrowths of lithium from touching and short-circuiting the battery.
For all the advantages of liquid electrolytes, though, scientists have long sought to develop solid alternatives. A solid electrolyte material would eliminate several issues at the same time. Most importantly, it would replace the membrane, allowing the electrodes to be placed much closer together without touching, thereby, making the battery more compact and boosting its energy density. A solid electrolyte would also make batteries stronger, potentially meaning that the amount of protective and structural casing could be cut without compromising on safety.

Unfortunately, the solid electrolytes proposed so far have generally fallen short in one way or another. In particular, they lack the necessary conductivity (expressed in milli-Siemens per centimetre, or mS/cm). Unsurprisingly, ions tend not to move as freely through a solid as they do through a liquid. That reduces both the speed at which a battery can charge and, conversely, the quantity of power it can release in a given time.

Scientists at imec – one of Europe’s premier nanotechnology R&D centres, and a partner in the EnergyVille consortium for sustainable energy and intelligent energy systems research – recently came up with a potential solution. The new material is a nanoporous oxide mix filled with ionic compounds and other additives, with the pores giving it a surface area of about 500 m²/mL – “comparable to an Olympic swimming pool folded into a shot glass,” says Philippe Vereecken, imec’s head of battery research. Because ions move faster along the pores’ surface than in the middle of a lithium salt electrolyte, he explains, this large surface area amplifies the ionic conductivity of the nanoengineered solid. The result is a material with a conductivity of 10 mS/cm at room temperature – equivalent to today’s liquid electrolytes.

Using this new electrolyte material, imec’s engineers have built a cell prototype using standard available electrodes: LFP (LiFePO₄) for the cathode and LTO (Li₄Ti₅O₁₂) for the anode. While charging, the new cell reached 80% of its capacity in one hour, which is already comparable to a similar cell made with a liquid electrolyte. Vereecken adds that the team hopes for even better results with future devices. “Computations show that the new material might even be engineered to sustain conductivities of up to 100 mS/cm,” he says.

Meanwhile, back at the electrode

Electrodes are conventionally made from sintered and compressed powders. Combining these with a solid electrolyte would normally entail mixing the electrode as a powder with the electrolyte also in powder form, and then compressing the result for a maximum contact. But even then, there will always remain pores and voids that are not filled and the contact surface will be much smaller than is possible with a liquid electrolyte that fully soaks the electrode.

Lithium-sulphur is a promising material that could store more energy than today’s technology allows

Imec’s new nano-composite material avoids this problem because it is actually applied as a liquid, via wet chemical coating, and only afterwards converted into a solid. That way it can impregnate dense powder electrodes, filling all cavities and making maximum contact just as a liquid electrolyte would. Another benefit is that even as a solid, the material remains somewhat elastic, which is essential as some electrodes expand and contract during battery charging and discharging. A final advantage is that because the solid material can be applied via a wet precursor, it is compatible with current Li-ion battery fabrication processes – something that Vereecken says is “quite important for the battery manufacturers” because otherwise more “disruptive” fabrication processes would have to be put in place.

To arrive at the energy densities required to give electric vehicles a long driving range, though, still more changes are needed. One possibility is to make the particles in the electrode powders smaller, so that they can be packed more densely. This would produce a larger contact surface with the electrolyte per volume, improving the energy density and charging rate of the cell. There is a catch, though: while a larger contact surface results in more ions being created and changing sides within the battery, it also gives more way for unwanted reactions that will degrade the battery’s materials and shorten its lifetime. “To improve the stability,” says Vereecken, “imec’s experts work on a solution where they coat all particles with an ultrathin buffer layer.” The challenge, he says, is to make these layers both chemically inert and highly conductive.

Introducing new materials

By combining solid electrolytes with thicker electrodes made from smaller particles, it may be possible to produce batteries with energy densities that exceed the current maximum of around 800 Wh/L. These batteries could also charge in 30 minutes or less. But to extend the energy density even further, to 1000 Wh/L and beyond, a worldwide effort is on to look for new and better electrode materials. Anodes, for example, are currently made from carbon in the form of graphite. That carbon could be replaced by silicon, which can hold up to ten times as many lithium ions per gram of electrode. The drawback is that when the battery is charged, a silicon anode will expand to more than three times its normal size as it fills with lithium ions. This may break up the electrode, and possibly even the battery casing.

A better alternative may be to replace carbon with pure lithium metal. A lithium anode will also store up to ten times as much lithium ions per gram of electrode as graphite, but without the swelling seen in silicon anodes. Lithium anodes were, in fact, used in the early days of Li-ion batteries, but as the metal is very reactive, especially in combination with liquid electrolytes, the idea was dropped in favour of more stable alternatives. Vereecken, however, believes that progress in solid electrolytes means it is “high time to revisit lithium metal as a material for the anode”, especially since it is possible to add protective functional coatings to nanoparticles.

Disruptive innovations are on the horizon for cathodes as well. Lithium-sulphur, for example, is a promising material that could store more energy than today’s technology allows. Indeed, the “ideal” lithium battery might well feature a lithium-air (lithium peroxide) cathode in combination with a pure lithium anode. But whereas the material composition of these batteries sounds simple, the path to realizing them will not be so easy, and there is still some way to go before any of these developments will be integrated into commercial batteries. Once that happens, though, huge payoffs are possible. The most obvious would be electrical cars that drive farther and charge faster, but better lithium batteries could also be the breakthrough needed to make renewable power ubiquitous – and thus finally let us off the fossil-fuel hook.

Genesis Nanotechnology, Inc. is pleased to present Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL! YouTube Video

 

 

Update: The Growth of EV Charging Stations in Europe – From Cities to Motorways: Video + Tony Seba on ‘Mobility Disruption’

The battle over how and where Europeans charge their electric cars is expanding from the cities to the motorway’s and beyond. But if electric vehicles (EVs) are ever to overtake petrol and diesel cars then charging will have to be as easy and simple as filling up. This video takes a look at the growth in electric vehicle charging stations and how the electric car market is forecasted to grow. As the electric vehicle market has grown, the need for more EV charging points has also grown.

Watch the Video Below

 

Read and Watch More: 

Mobility Disruption | Tony Seba, Silicon Valley Entrepreneur and Lecturer at Stanford University

Tony Seba, Silicon Valley entrepreneur, Author and Thought Leader, Lecturer at Stanford University, Keynote The reinvention and connection between infrastructure and mobility will fundamentally disrupt the clean transport model. It will change the way governments and consumers think about mobility, how power is delivered and consumed and the payment models for usage.

 

Have You Watched Tenka Energy’s Video on New Nano-Enabled Batteries and Super Capacitors for the EV Markets?

 

Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL!

 

 

Are Sustainable Super-capacitors from Wood (yes w-o-o-d) the Answer for the Future of Energy Storage? Researchers at UST China Think ‘Nano-Cellulose’ may Hold the Key

Supercapacitors are touted by many as the wave of the future when it comes to battery storage for everything from cell phones to electric cars.

Unlike batteries, supercapacitors can charge and discharge much more rapidly — a boon for impatient drivers who want to be able to charge their electric cars quickly.

The key to supercap performance is electrodes with a large surface area and high conductivity that are inexpensive to manufacture, according to Science Daily.

Carbon aerogels satisfy the first two requirements but have significant drawbacks. Some are made from phenolic precursors which are inexpensive but not environmentally friendly. Others are made from  graphene and carbon nanotube precursors but are costly to manufacture.

Researchers at the University of Science and Technology of China have discovered a new process that is low cost and sustainable using nanocellulose, the primary component of wood pulp that gives strength to the cell walls of trees.

Once extracted in the lab, it forms a stable, highly porous network which when oxidized forms a micro-porous hydrogel of highly oriented cellulose nano-fibrils of uniform width and length.

Like most scientific research, there was not a straight line between the initial discovery and the final process.

A lot of tweaking went on in the lab to get things to work just right. Eventually, it was found that heating the hydrogel in the presence of para-toluenesulfonic acid, an organic acid catalyst, lowered the decomposition temperature and yielded a “mechanically stable and porous three dimensional nano-fibrous network” featuring a “large specific surface area and high electrical conductivity,” the researchers say in a report published by the journal Angewandte Chemie International.

The chemists have been able to create a low cost, environmentally friendly wood-based carbon aerogel that works well as a binder-free electrode for supercapacitor applications with electro-chemical properties comparable to commercial electrodes currently in use.

Now the hard work of transitioning this discovery from the laboratory to commercial viability will begin. Contributed by Steve Hanley

Watch Tenka Energy’s YouTube Video

Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL!

MIT Technolgy Review: This battery advance could make electric vehicles far cheaper

Sila Nanotechnologies has pulled off double-digit performance gains for lithium-ion batteries, promising to lower costs or add capabilities for cars and phones.

For the last seven years, a startup based in Alameda, California, has quietly worked on a novel anode material that promises to significantly boost the performance of lithium-ion batteries.

Sila Nanotechnologies emerged from stealth mode last month, partnering with BMW to put the company’s silicon-based anode materials in at least some of the German automaker’s electric vehicles by 2023.

A BMW spokesman told the Wall Street Journal the company expects that the deal will lead to a 10 to 15 percent increase in the amount of energy you can pack into a battery cell of a given volume. Sila’s CEO Gene Berdichevsky says the materials could eventually produce as much as a 40 percent improvement (see “35 Innovators Under 35: Gene Berdichevsky”).

For EVs, an increase in so-called energy density either significantly extends the mileage range possible on a single charge or decreases the cost of the batteries needed to reach standard ranges. For consumer gadgets, it could alleviate the frustration of cell phones that can’t make it through the day, or it might enable power-hungry next-generation features like bigger cameras or ultrafast 5G networks.

Researchers have spent decades working to advance the capabilities of lithium-ion batteries, but those gains usually only come a few percentage points at a time. So how did Sila Nanotechnologies make such a big leap?

Berdichevsky, who was employee number seven at Tesla, and CTO Gleb Yushin, a professor of materials science at the Georgia Institute of Technology, recently provided a deeper explanation of the battery technology in an interview with MIT Technology Review.

Sila co-founders (from left to right), Gleb Yushin, Gene Berdichevsky and Alex Jacobs.

An anode is the battery’s negative electrode, which in this case stores lithium ions when a battery is charged. Engineers have long believed that silicon holds great potential as an anode material for a simple reason: it can bond with 25 times more lithium ions than graphite, the main material used in lithium-ion batteries today.

But this comes with a big catch. When silicon accommodates that many lithium ions, its volume expands, stressing the material in a way that tends to make it crumble during charging. That swelling also triggers electrochemical side reactions that reduce battery performance.

In 2010, Yushin coauthored a scientific paper that identified a method for producing rigid silicon-based nanoparticles that are internally porous enough to accommodate significant volume changes. He teamed up with Berdichevsky and another former Tesla battery engineer, Alex Jacobs, to form Sila the following year.

The company has been working to commercialize that basic concept ever since, developing, producing, and testing tens of thousands of different varieties of increasingly sophisticated anode nanoparticles. It figured out ways to alter the internal structure to prevent the battery electrolyte from seeping into the particles, and it achieved dozens of incremental gains in energy density that ultimately added up to an improvement of about 20 percent over the best existing technology.

Ultimately, Sila created a robust, micrometer-size spherical particle with a porous core, which directs much of the swelling within the internal structure. The outside of the particle doesn’t change shape or size during charging, ensuring otherwise normal performance and cycle life.

The resulting composite anode powders work as a drop-in material for existing manufacturers of lithium-ion cells.

With any new battery technology, it takes at least five years to work through the automotive industry’s quality and safety assurance processes—hence the 2023 timeline with BMW. But Sila is on a faster track with consumer electronics, where it expects to see products carrying its battery materials on shelves early next year.

Venkat Viswanathan, a mechanical engineer at Carnegie Mellon, says Sila is “making great progress.” But he cautions that gains in one battery metric often come at the expense of others—like safety, charging time, or cycle life—and that what works in the lab doesn’t always translate perfectly into end products.

Companies including Enovix and Enevate are also developing silicon-dominant anode materials. Meanwhile, other businesses are pursuing entirely different routes to higher-capacity storage, notably including solid-state batteries. These use materials such as glass, ceramics, or polymers to replace liquid electrolytes, which help carry lithium ions between the cathode and anode.

BMW has also partnered with Solid Power, a spinout from the University of Colorado Boulder, which claims that its solid-state technology relying on lithium-metal anodes can store two to three times more energy than traditional lithium-ion batteries. Meanwhile, Ionic Materials, which recently raised $65 million from Dyson and others, has developed a solid polymer electrolyte that it claims will enable safer, cheaper batteries that can operate at room temperature and will also work with lithium metal.

Some battery experts believe that solid-state technology ultimately promises bigger gains in energy density, if researchers can surmount some large remaining technical obstacles.

But Berdichevsky stresses that Sila’s materials are ready for products now and, unlike solid-state lithium-metal batteries, don’t require any expensive equipment upgrades on the part of battery manufacturers.

As the company develops additional ways to limit volume change in the silicon-based particles, Berdichevsky and Yushin believe they’ll be able to extend energy density further, while also improving charging times and total cycle life.

This story was updated to clarify that Samsung didn’t invest in Ionic Material’s most recent funding round.

Read and Watch More:

Tenka Energy, Inc. Building Ultra-Thin Energy Dense SuperCaps and NexGen Nano-Enabled Pouch & Cylindrical Batteries – Energy Storage Made Small and POWERFUL! YouTube Video:

MIT: Finding a New Way to Design and Analyze Better Battery Materials: Discoveries could accelerate the development of high-energy lithium batteries

Diagram illustrates the crystal lattice of a proposed battery electrolyte material called Li3PO4. The researchers found that measuring how vibrations of sound move through the lattice could reveal how well ions – electrically charged atoms or molecules – could travel through the solid material, and therefore how they would work in a real battery. In this diagram, the oxygen atoms are shown in red, the purple pyramid-like shapes are phosphate (PO4) molecules. The orange and green spheres are ions of lithium.
Image: Sokseiha Muy

Design principles could point to better electrolytes for next-generation lithium batteries.

A new approach to analyzing and designing new ion conductors — a key component of rechargeable batteries — could accelerate the development of high-energy lithium batteries and possibly other energy storage and delivery devices such as fuel cells, researchers say.

The new approach relies on understanding the way vibrations move through the crystal lattice of lithium ion conductors and correlating that with the way they inhibit ion migration. This provides a way to discover new materials with enhanced ion mobility, allowing rapid charging and discharging.

At the same time, the method can be used to reduce the material’s reactivity with the battery’s electrodes, which can shorten its useful life. These two characteristics — better ion mobility and low reactivity — have tended to be mutually exclusive.

The new concept was developed by a team led by W.M. Keck Professor of Energy Yang Shao-Horn, graduate student Sokseiha Muy, recent graduate John Bachman PhD ’17, and Research Scientist Livia Giordano, along with nine others at MIT, Oak Ridge National Laboratory, and institutions in Tokyo and Munich. Their findings were reported in the journal Energy and Environmental Science.

The new design principle has been about five years in the making, Shao-Horn says. The initial thinking started with the approach she and her group have used to understand and control catalysts for water splitting, and applying it to ion conduction — the process that lies at the heart of not only rechargeable batteries, but also other key technologies such as fuel cells and desalination systems.

While electrons, with their negative charge, flow from one pole of the battery to the other (thus providing power for devices), positive ions flow the other way, through an electrolyte, or ion conductor, sandwiched between those poles, to complete the flow.

Typically, that electrolyte is a liquid. A lithium salt dissolved in an organic liquid is a common electrolyte in today’s lithium-ion batteries. But that substance is flammable and has sometimes caused these batteries to catch fire. The search has been on for a solid material to replace it, which would eliminate that issue.

A variety of promising solid ion conductors exist, but none is stable when in contact with both the positive and negative electrodes in lithium-ion batteries, Shao-Horn says.

Therefore, seeking new solid ion conductors that have both high ion conductivity and stability is critical. But sorting through the many different structural families and compositions to find the most promising ones is a classic needle in a haystack problem. That’s where the new design principle comes in.

The idea is to find materials that have ion conductivity comparable to that of liquids, but with the long-term stability of solids. The team asked, “What is the fundamental principle? What are the design principles on a general structural level that govern the desired properties?” Shao-Horn says. A combination of theoretical analysis and experimental measurements has now yielded some answers, the researchers say.

“We realized that there are a lot of materials that could be discovered, but no understanding or common principle that allows us to rationalize the discovery process,” says Muy, the paper’s lead author. “We came up with an idea that could encapsulate our understanding and predict which materials would be among the best.”

The key was to look at the lattice properties of these solid materials’ crystalline structures. This governs how vibrations such as waves of heat and sound, known as phonons, pass through materials. This new way of looking at the structures turned out to allow accurate predictions of the materials’ actual properties. “Once you know [the vibrational frequency of a given material], you can use it to predict new chemistry or to explain experimental results,” Shao-Horn says.

The researchers observed a good correlation between the lattice properties determined using the model and the lithium ion conductor material’s conductivity. “We did some experiments to support this idea experimentally” and found the results matched well, she says.

They found, in particular, that the vibrational frequency of lithium itself can be fine-tuned by tweaking its lattice structure, using chemical substitution or dopants to subtly change the structural arrangement of atoms.

The new concept can now provide a powerful tool for developing new, better-performing materials that could lead to dramatic improvements in the amount of power that could be stored in a battery of a given size or weight, as well as improved safety, the researchers say.

Already, they used the method to find some promising candidates. And the techniques could also be adapted to analyze materials for other electrochemical processes such as solid-oxide fuel cells, membrane based desalination systems, or oxygen-generating reactions.

The team included Hao-Hsun Chang at MIT; Douglas Abernathy, Dipanshu Bansal, and Olivier Delaire at Oak Ridge; Santoshi Hori and Ryoji Kanno at Tokyo Institute of Technology; and Filippo Maglia, Saskia Lupart, and Peter Lamp at Research Battery Technology at BMW Group in Munich.

The work was supported by BMW, the National Science Foundation, and the U.S. Department of Energy.

Watch a YouTube Video on New Nano-Enabled Super Capacitors and Batteries

Is This the Battery Boost We’ve Been Waiting For?

Electric cars are among the products that stand to benefit from new lithium-ion cells that could store as much as 40% more energy. A BMW i Vision Dynamics concept electric automobile, made by BMW AG, on display in September. PHOTO: SIMON DAWSON/BLOOMBERG

The batteries that power our modern world—from phones to dronesto electric cars—will soon experience something not heard of in years: Their capacity to store electricity will jump by double-digit percentages, according to researchers, developers and manufacturers.

The next wave of batteries, long in the pipeline, is ready for commercialization. This will mean, among other things, phones with 10% to 30% more battery life, or phones with the same battery life but faster and lighter or with brighter screens. We’ll see more cellular-connected wearables. As this technology becomes widespread, makers of electric vehicles and home storage batteries will be able to knock thousands of dollars off their prices over the next five to 10 years. Makers of electric aircraft will be able to explore new designs.

There is a limit to how far lithium-ion batteries can take us; surprisingly, it’s about twice their current capacity. The small, single-digit percentage improvements we see year after year typically are because of improvements in how they are made, such as small tweaks to their chemistry or new techniques for filling battery cells with lithium-rich electrolyte. What’s coming is a more fundamental change to the materials that make up a battery.

Equipment that Sila Nanotechnologies uses to manufacture material for lithium-silicon batteries. PHOTO: SILA NANOTECHNOLOGIES

 

First, some science: Every lithium-ion battery has an anode and a cathode. Lithium ions traveling between them yield the electrical current that powers our devices. When a battery is fully charged, the anode has sucked up lithium ions like a sponge. And as it discharges, those ions travel through the electrolyte, to the cathode.

Typically, anodes in lithium-ion batteries are made of graphite, which is carbon in a crystalline form. While graphite anodes hold a substantial number of lithium ions, researchers have long known a different material, silicon, can hold 25 times as many.

The trick is, silicon brings with it countless technical challenges. For instance, a pure silicon anode will soak up so many lithium ions that it gets “pulverized” after a single charge, says George Crabtree, director of the Joint Center for Energy Storage Research, established by the U.S. Department of Energy at the University of Chicago Argonne lab to accelerate battery research.

Current battery anodes can have small amounts of silicon, boosting their performance slightly. The amount of silicon in a company’s battery is a closely held trade secret, but Dr. Crabtree estimates that in any battery, silicon is at most 10% of the anode. In 2015, Tesla founder Elon Musk revealed that silicon in the Panasonic-made batteries of the auto maker’s Model S helped boost the car’s range by 6%.

Now, some startups say they are developing production-ready batteries with anodes that are mostly silicon. Sila Nanotechnologies,Angstron Materials , Enovix and Enevate, to name a few, offer materials for so-called lithium-silicon batteries, which are being tested by the world’s largest battery manufacturers, car companies and consumer-electronics companies.

Prototype batteries built at Sila with the startup’s silicon-dominant anode technology. PHOTO: SILA NANOTECHNOLOGIES

For Sila, in Alameda, Calif., the secret is nanoparticles lots of empty space inside. This way, the lithium can be absorbed into the particle without making the anode swell and shatter, says Sila Chief Executive Gene Berdichevsky. Cells made with Sila’s particles could store 20% to 40% more energy, he adds.

Angstron Materials, in Dayton, Ohio, makes similar claims about its nanoparticles for lithium-ion batteries.

Dr. Crabtree says this approach is entirely plausible, though there’s a trade-off: By allowing more room inside the anode for lithium ions, manufacturers must produce a larger anode. This anode takes up more space in the battery, allowing less overall space to increase capacity. This is why the upper bound of increased energy density using this approach is about 40%.

The big challenge, as ever, is getting to market, says Dr. Crabtree.

Sila’s clients include BMW and Amperex Technology , one of the world’s largest makers of batteries for consumer electronics, including both Apple ’s iPhone and Samsung ’s Galaxy S8 phone.

China-based Amperex is also an investor in Sila, but Amperex Chief Operating Officer Joe Kit Chu Lam says his company is securing several suppliers of the nanoparticles necessary to produce lithium-silicon batteries. Having multiple suppliers is essential for securing enough volume, he says.

This nanoparticle of carbon and silicon, made by Global Graphene Group, could help lithium-ion batteries store significantly more energy. PHOTO: GLOBAL GRAPHENE GROUP

The first commercial consumer devices to have higher-capacity lithium-silicon batteries will likely be announced in the next two years, says Mr. Lam, who expects a wearable to be first. Other companies claim a similar timetable for consumer rollout.

Enevate produces complete silicon-dominant anodes for car manufacturers. CEO Robert Rango says its technology increases the range of electric vehicles by 30% compared with conventional lithium-ion batteries.

BMW plans to incorporate Sila’s silicon anode technology in a plug-in electric vehicle by 2023, says a company spokesman. BMW expects an increase of 10% to 15% in battery-pack capacity in a single leap. While this is the same technology destined for mobile electronics, the higher volumes and higher safety demands of the auto industry mean slower implementation there. In 2017, BMW said it would invest €200 million ($246 million) in its own battery-research center.

Enovix, whose investors include Intel and Qualcomm, has pioneered a different kind of 3-D structure for its batteries, says CEO Harrold Rust. With much higher energy density and anodes that are almost pure silicon, the company claims its batteries would contain 30% to 50% more energy in the size needed for a mobile phone, and two to three times as much in the size required for a smartwatch.

The downside: producing these will require a significant departure from the current manufacturing process.

Even though it’s a significant advance, to get beyond what’s possible with lithium-silicon batteries will require a change in battery composition—such as lithium-sulfur chemistry or solid-state batteries. Efforts to make these technologies viable are at a much earlier stage, however, and it isn’t clear when they’ll arrive.

Meanwhile, we can look forward to the possibility of a thinner or more capable Apple Watch, wireless headphones we don’t have to charge as often and electric vehicles that are actually affordable. The capacity of lithium-ion batteries has increased threefold since their introduction in 1991, and at every level of improvement, new and unexpected applications, devices and business opportunities pop up.

 

Corrections & Amplifications 

Sila Nanotechnologies produces nanoparticles that contain silicon and other components, but don’t include graphite. A previous version of this column incorrectly described nanoparticles as a graphite-silicon composite. An earlier version also incorrectly identified Angstron Materials as Angstrom Materials. (Angstron error corrected: March 18, 2018. Nanoparticles error corrected: March 19, 2018

 

Appeared in the March 19, 2018, print edition as ‘Battery Life Powers Ahead Toward Sizable Gains.’

Have you seen Tenka Energy’s YouTube Video?  Watch Here:

Design for new electrode could boost supercapacitors’ performance – UCLA Researchers Design Super-efficient and Long-lasting electrode for Supercapacitors – 10X Efficiency

IMAGE: THE BRANCH-AND-LEAVES DESIGN IS MADE UP OF ARRAYS OF HOLLOW, CYLINDRICAL CARBON NANOTUBES (THE ‘BRANCHES’) AND SHARP-EDGED PETAL-LIKE STRUCTURES (THE ‘LEAVES’) MADE OF GRAPHENE. view more  CREDIT: UCLA ENGINEERING

Engineers from UCLA, 4 other universities produce nanoscale device that mimics the structure of tree branches

UCLA HENRY SAMUELI SCHOOL OF ENGINEERING OF APPLIED SCIENCE

Mechanical engineers from the UCLA Henry Samueli School of Engineering and Applied Science and four other institutions have designed a super-efficient and long-lasting electrode for supercapacitors. The device’s design was inspired by the structure and function of leaves on tree branches, and it is more than 10 times more efficient than other designs.

 

The branch-and-leaves design is made up of arrays of hollow, cylindrical carbon nanotubes (the “branches”) and sharp-edged petal-like structures (the “leaves”) made of graphene.

The electrode design provides the same amount of energy storage, and delivers as much power, as similar electrodes, despite being much smaller and lighter. In experiments it produced 30 percent better capacitance — a device’s ability to store an electric charge — for its mass compared to the best available electrode made from similar carbon materials, and 30 times better capacitance per area. It also produced 10 times more power than other designs and retained 95 percent of its initial capacitance after more than 10,000 charging cycles.

Their work is described in the journal Nature Communications.

Supercapacitors are rechargeable energy storage devices that deliver more power for their size than similar-sized batteries. They also recharge quickly, and they last for hundreds to thousands of recharging cycles. Today, they’re used in hybrid cars’ regenerative braking systems and for other applications. Advances in supercapacitor technology could make their use widespread as a complement to, or even replacement for, the more familiar batteries consumers buy every day for household electronics.

Engineers have known that supercapacitors could be made more powerful than today’s models, but one challenge has been producing more efficient and durable electrodes. Electrodes attract ions, which store energy, to the surface of the supercapacitor, where that energy becomes available to use. Ions in supercapacitors are stored in an electrolyte solution. An electrode’s ability to deliver stored power quickly is determined in large part by how many ions it can exchange with that solution: The more ions it can exchange, the faster it can deliver power.

Knowing that, the researchers designed their electrode to maximize its surface area, creating the most possible space for it to attract electrons. They drew inspiration from the structure of trees, which are able to absorb ample amounts of carbon dioxide for photosynthesis because of the surface area of their leaves.

“We often find inspiration in nature, and plants have discovered the best way to absorb chemicals such as carbon dioxide from their environment,” said Tim Fisher, the study’s principal investigator and a UCLA professor of mechanical and aerospace engineering. “In this case, we used that idea but at a much, much smaller scale — about one-millionth the size, in fact.”

To create the branch-and-leaves design, the researchers used two nanoscale structures composed of carbon atoms. The “branches” are arrays of hollow, cylindrical carbon nanotubes, about 20 to 30 nanometers in diameter; and the “leaves” are sharp-edged petal-like structures, about 100 nanometers wide, that are made of graphene — ultra thin sheets of carbon. The leaves are then arranged on the perimeter of the nanotube stems. The leaf-like graphene petals also give the electrode stability.

The engineers then formed the structures into tunnel-shaped arrays, which the ions that transport the stored energy flow through with much less resistance between the electrolyte and the surface to deliver energy than they would if the electrode surfaces were flat.

The electrode also performs well in acidic conditions and high temperatures, both environments in which supercapacitors could be used.

###

Fisher directs UCLA’s Nanoscale Transport Research Group and is a member of the California NanoSystems Institute at UCLA. Lei Chen, a professor at Mississippi State, was the project’s other principal investigator. The first authors are Guoping Xiong of the University of Nevada, Reno, and Pingge He of Central South University. The research was supported by the Air Force Office of Scientific Research.

 

Nikola Plans $1 Billion Buckeye, Arizona Fuel Cell Truck Factory

Hydrogen-electric semi-truck startup Nikola Motor Co. plans to build a $1 billion factory in a Phoenix suburb.

The company detailed its plans Tuesday in a joint announcement with Arizona Governor Doug Ducey.

The fuel cell truck developer said it will build a 500-acre, 1 million square foot facility west of Phoenix in Buckeye.

Trevor Milton, Nikola’s chief executive, and Ducey said the plant will create 2,000 jobs and bring more than $1 billion in capital investment to the region by 2024.

Arizona will provide up to $46.5 million in various job training and tax abatement incentives. But the package is performance-based and Nikola benefits only if it makes investments in plant and employees, said Susan E. Marie, senior vice president of the Arizona Commerce Authority.

“Arizona has the workforce to support our growth and a governor that was an entrepreneur himself. They understood what 2,000 jobs would mean to their cities and state,” Milton said.

Nikola will relocate its headquarters and research and development team from Salt Lake City to Arizona by October.

Nikola says it has 8,000 pre-orders for its fuel cell truck.

Ryder System Inc. will serve as Nikola’s exclusive provider for distribution and maintenance nationwide and in parts of Mexico. Caterpillar dealer and early Nikola investor Thompson Machinery will supplement Ryder’s sales and services in Tennessee and Mississippi.

Nikola said its Nikola One sleeper and Nikola Two day cab trucks will be able to run up to 1,200 miles between refueling stops.  The company plans to lease the trucks to users. It will supply fuel as part of the lease cost through a nationwide network of 376 hydrogen fueling stations. It still has to build the network.

The powertrain is rated by the company at 1,000 horsepower and 2,000 pound-feet of torque, which analysts said fits the need for long haul trucking.

“This incredible new technology will revolutionize transportation, and we’re very proud it will be engineered right here in Arizona,” Ducey said. Nikola’s “selection of Arizona demonstrates that we are leading the charge when it comes to attracting innovative, industry-disrupting companies.”

While the factory is under construction truck components company Fitzgerald Gliders will build the first 5,000 production models.

Nikola did not provide any details on how it would fund building the factory.  But in December, truck components company Wabco Holdings acquired a 1 percent stake in Nikola for  $10 million. That deal valued the startup at $1 billion.

The company also raised $110 million in a funding round last year.

“A key challenge for Nikola is to demonstrate that they can raise the significant capital necessary to be a true competitor in this space,” said John Boesel, chief executive of Pasadena-based clean transportation incubator Calstart.

However, Boesel said there is room for Nikola.

“Zero emission truck technology is rapidly evolving,” he said. “There is the opportunity for disruptive companies like Nikola to come into this space.”

Nikola has partnered with well-regarded truck components manufacturers, a smart move that builds confidence in potential customers, said Antti Lindstrom, an analyst with IHS Markit.

It has tapped parts supplier Bosch for joint development of powertrain systems for the Nikola One and the Nikola Two. Bosch also has worked with Nikola to develop the truck’s “eAxle,” which houses the electric motor, transmission and power electronics.

Swedish fuel cell developer PowerCell AB will provide the fuel cell stacks that produce electricity from hydrogen, and Nikola will build the completed fuel cell system.

Nikola plans field tests of truck prototypes this fall using the Nikola Two truck and Nikola test divers. Real-world testing with potential fleet customers will come after that. Testing of the Nikola One sleeper truck will begin later.

“I believe the fuel cell solution is better than battery electric trucks for long haul deliveries,” Lindstrom said. “You don’t have the same weight issue that you have with heavy batteries.”

That allows trucks to have a longer range between fueling and enables heavier freight loads, he said.

“This is a technology that is here and now,” Lindstrom said. “It doesn’t require advancement in technology that battery electric long-haul trucks will require.”

Nikola, however, faces potential competition from well capitalized and mature rivals.

Other players include Toyota, which is testing a Class 8 fuel cell electric drayage truck in Southern California. Kenworth, the Paccar brand, is developing a Class 8 hydrogen fuel cell electric truck prototype.

A host of companies including Tesla, Daimler Trucks, Volvo Trucks, Navistar and Cummins are working on electric trucks that could compete with fuel cell commercial vehicles.

Milton said Nikola settled on Buckeye following a 12-month site selection process that considered nine states and 30 different locations. He said he liked the city’s economic environment, engineering schools, educated workforce and geographic location that provides direct access to major markets.

“The Greater Phoenix region is elevating its brand as a hub for innovation, and companies such as Nikola have taken notice,” said Chris Camacho, chief executive of the Greater Phoenix Economic Council.

Read Next: The Economic Case For The Tesla Semi-Truck