Could Form Energy’s “Iron-Air-Exchange Batteries” be the Holy Grail Answer to Large Scale Energy Storage? Ingredients? Rust And Salt

Form Energy Battery System Rendering. Courtesy Form Energy

Salt and rust – the bane of your car’s existence — may be the keys to storing enough renewable energy to power the electric grid for several days. That’s according to two local companies that have emerged with innovative battery designs based on cheap, widely-available materials.

After four years of stealth R&D, Somerville-based Form Energyhas emerged with what could be a breakthrough energy storage technology, based on rust.

Form Energy president and CEO Ted Wiley says the company has produced hundreds of working prototypes of an iron-air-exchange battery that can store large amounts of energy for several days.

“We’ve completed the science,” says Wiley, “what’s left to do is scale up from lab-scale protoypes to grid-scale power plants. “

In full production, “the modules will produce electricity for one-tenth the cost of any technology available today for grid storage,” Wiley says.

If the plan comes to fruition, Form Energy’s batteries could realize what’s called “the renewable energy Holy Grail” — relatively inexpensive, reliable grid-scale energy storage. Because solar and wind do not generate power when the sun is down or the wind isn’t blowing, storing their power for down times is the key to clean energy reliability.

The Form Energy battery is composed of cells filled with thousands of small iron pellets that, rust when exposed to air. When oxygen is removed the rust reverts to iron. By controlling the process the battery is charged and discharged.

The iron anode section of Form Energy's prototype iron-air battery. Courtesy Form Energy
The iron anode section of Form Energy’s prototype iron-air battery. Courtesy Form Energy

The plan is to mount small cells into larger modules, then assemble modules into batteries that can be scaled to power electric grids. Wiley expects to have a 300Mwh, full-scale pilot project, using 500 modules, up and running at the Great River Energy power plant in Minnesota in 2023.

In nearby Cambridge, researchers at Malta, Inc. are working on an energy storage technology based on an equally humble material: molten salt.

Electricity from the grid is converted into thermal energy and stored as heat in trays of molten sodium. When the grid needs energy the process is reversed and the molten sodium is used to generate electricity.

A high-energy density and long-life initial-anode-free lithium battery

a-high-energy-density battery 071421
Cathode and electrolyte design strategies for the researchers’ anode-free Li cell system. Credit: Qiao et al.

Lithium-metal batteries (LMBs), an emerging type of rechargeable lithium-based batteries made of solid-state metal instead of lithium-ions, are among the most promising high-energy-density rechargeable battery technologies. Although they have some advantageous characteristics, these batteries have several limitations, including a poor energy density and safety-related issues.

In recent years, researchers have tried to overcome these limitations by introducing an alternative, anode-free lithium battery cell design. This anode-free design could help to increase the  density and safety of .

Researchers at the National Institute of Advanced Industrial Science and Technology recently carried out a study aimed at increasing the energy density of anode-free lithium batteries. Their paper, published in Nature Energy, introduces a new high-energy-density and long-life anode-free lithium battery based on the use of a Li2O sacrificial agent.

Anode-free full-cell battery architectures are typically based on a fully lithiated cathode with a bare anode copper current collector. Remarkably, both the gravimetric and volumetric energy densities of anode-free lithium batteries can be extended to their maximum limit. Anode-free cell architectures have several other advantages over more conventional LMB designs, including a lower cost, greater safety and simpler cell assembly procedures.

To unlock the full potential of anode-free LMBs, researchers should first figure out how to achieve the reversibility/stability of Li-metal plating. While many have tried to solve this problem by engineering and selecting more favorable electrolytes, most of these efforts have so far been unsuccessful.

Others have also explored the potential of using salts or additives that could improve the Li-metal plating/stripping reversibility. After reviewing these previous attempts, the researchers at the National Institute of Advanced Industrial Science and Technology proposed the use of Li2O as a sacrificial agent, which is pre-loaded onto a LiNi0.8Co0.1Mn0.1O2 surface.

“It is challenging to realize high Li reversibility, especially considering the limited Li reservoir (typically zero lithium excess) in the cell configuration,” the researchers wrote in their paper. “In this study we have introduced Li2O as a preloaded sacrificial agent on a LiNi0.8Co0.1Mn0.1O2 cathode, providing an additional Li source to offset the irreversible loss of Li during long-term cycling in an initial-anode-free cell.”

In addition to employing Li2O as a sacrificial agent, the researchers proposed the use of a fluoropropyl ether additive to neutralize nucleophilic O2-, which is released during the oxidation of Li2O, and prevent the additional evolution of gaseous O2 resulting from the fabrication of a LiF-based electrolyte coated on the surface of the battery’s cathode.

“We show that O2– species, released through Li2O oxidation, are synergistically neutralized by a fluorinated ether additive,” the researchers explained in their paper. “This leads to the construction of a LiF-based layer at the cathode/electrolyte interface, which passivates the cathode surface and restrains the detrimental oxidative decomposition of ether solvents.”

Based on the design they devised, Yu Qiao and the rest of the team at the National Institute of Advanced Industrial Science and Technology were able to realize a long-life 2.46 Ah initial-anode-free pouch cell. This cell exhibited a gravimetric  of 320 Wh kg-1, maintaining an 80% capacity after 300 operation cycles.

In the future, the anode-free lithium battery introduced by this research group could help to overcome some of the commonly reported limitations of LMBs. In addition, its design could inspire the creation of safer lithium-based rechargeable batteries with higher energy densities and longer lifetimes.

Explore further

An anode-free zinc battery that could someday store renewable energyMore information: A high-energy-density and long-life initial-anode-free lithium battery enabled by a Li2O sacrificial agent. Nature Energy(2021). DOI: 10.1038/s41560-021-00839-0.

Journal information: Nature Energy

10 Predictions for the Solar and Storage Market in the 2020s

Rooftop_Solar_Community_Austin_Texas_Shutterstock_XL_721_420_80_s_c1Branding and reputation will be increasingly important in the energy storage market.

All-in-one systems will be the new normal

1. Lots of storage

Batteries will be incentivized or mandated for practically every new solar PV system across the U.S. by 2025. As more homeowners and businesses deploy PV systems to reduce their electricity bills and ensure backup power, simple net metering will increasingly be replaced by time-of-use rates and other billing mechanisms that aim to align power prices with utility costs. We already see these trends in California and several states in the Northeast.


Solar systems with batteries are going to be about twice as expensive as traditional grid-direct installations, so in that sense, we will see actual costs increase as the mix shifts toward batteries. But while system costs will go up, we need to be careful to parse the actual equipment and soft costs from the consumer’s cost net of tax credits and incentives. Equipment costs for batteries and other hardware are generally flat to slightly down.

3. More battery and inverter packages from the same brand

Since the battery represents the dominant cost in an energy storage system (ESS), inverter companies will increasingly offer branded batteries. In turn, inverter companies packaging third-party batteries will eventually make way for savvy battery companies that can package the whole system.

4. Energy storage systems treated like heat pumps and air conditioners

California’s new Title 21 requirements make solar PV systems standard issue, and we can expect a future update to do the same for energy storage. By then, builders will be able to choose the ESS line they want to work with, and the whole process will look almost exactly like it does for home mechanical appliances like water heaters and HVAC systems. The only question will be whether the ESS is packaged with solar panels or kept separate.

Standards will evolve

5. Reputation will matter — a lot

The lack of meaningful industry metrics in energy storage creates an environment where branding and reputation become important, since users have little information beyond messaging and word of mouth. Long-term, this will create a barrier to entry for new battery startups, so expect fewer total players once a handful of brands emerge as high-confidence choices.

6. New safety standards and code requirements catch up to technology

Last October, the National Fire Protection Association published the first edition of the NFPA 855 code, which establishes an industrywide safety standard for energy storage systems. Test standards, including UL 9540, and UL 9540A, as well as building and electrical codes, such as the National Electrical Code (NEC/NFPA 70), International Residential Code and International Fire Code, are already being updated to harmonize with NFPA 855. The upshot is that kilowatt-hour capacity limits, siting and protective equipment requirements are becoming standardized and more accessible for both installers and inspectors to understand and apply.

All things will remain technical

7. Real automation and optimization software will outpace flashy interfaces

Third-party owners have specific PV fleet-management needs and often have proprietary software that their ESS needs to interface with daily. IEEE 2030.5 and related standards will help facilitate this need. Local installers have little in the way of hard requirements, but they and their customers will expect systems to be easy to install and operate.

In the long term, we’ll see real automation and optimization rather than the data-palooza common today. Many interfaces report too much data, and simplifying systems to hide irrelevant data will be necessary to avoid alienating the more mainstream consumers.

8. Still waiting for vehicle-to-grid

While V2G is not primarily a technical challenge, some manufacturers like Nissan and Honda have made significant headway. The challenge is more procedural than technical. V2G applications will take off when vehicle manufacturers and interface providers come to terms with how and when an electric vehicle’s battery is used for grid services or backup and how that impacts the EV’s warranty.

There’s also a consumer confidence problem to overcome, especially for those relying solely on their EV for transportation. We’re more likely to see “second-life” EV batteries repackaged for stationary storage — which is much easier to manage than trying to use the battery in the car.

9. AC and DC coupling will both be around for the foreseeable future

Given the latest National Electrical Code requirements for rapid shutdown, as well as the fact that module-level systems (e.g., Enphase and SolarEdge) represent the majority of installed systems, AC coupling is the clear choice for existing system owners to add batteries.

AC coupling will enjoy at least a temporary boom in popularity as people with existing PV systems seek to add storage. However, most advantages of AC coupling are for retrofits, and the majority of new systems will enjoy lower costs and better performance via DC coupling. DC coupling is arguably going to become more dominant once the PV-only retrofit market is saturated.

10. Battery pack voltage will increase dramatically

A century of lead-acid battery dominance has entrenched 48 volts (DC) as the standard battery system voltage. Systems with voltages up to 1,000 VDC are deployed using standard lead-acid cells, but it is only practical for engineered commercial and industrial or utility systems.

The Ohm’s law tradeoff between current and voltage pushed the EV industry, which needs to reduce weight and cost everywhere it can, to quickly migrate to high-voltage battery packs using 3- to 4-VDC lithium-ion cells. Similarly, the stationary energy storage industry is adopting higher-voltage battery packs to reduce the cost of battery inverters. Since conductor losses increase and decrease exponentially with current, higher battery voltages also enable better system efficiency.

The decade of the 2020s will ring in the age of mass solar-plus-storage solution deployment, allowing businesses and residents to tap into renewables more efficiently, protect against outages, save money and live more sustainably.

*** Re-Posted from Green-Tech Media

Three Innovations To Upend The Energy Storage Market

The battery craze isn’t really about batteries at all. It’s about something far grander than a battery, which is simply a conduit to a much bigger story.

Batteries are like the internet without Wifi. 

The holy grail is energy storage.

And while perpetually bigger batteries themselves have emerged as the dominant solution to our energy storage needs, their reliance on rare earths elements and some metals that are controversially sourced, as well as the fact that their product life is quite limited, indicates they are simply a stop along the way to more creative innovations. 

Already, there are several challenger solutions that have the potential to rise above the battery as the answer to our energy storage needs.


One of these solutions is gravity. Several companies across the world are using gravity for energy storage or rather, moving objects up and down to store and, respectively, release stored electricity.

One of these, Swiss-based Energy Vault, uses a six headed crane to lift bricks when renewable installations are producing electricity than can be consumed and drop them back down when demand for electricity outweighs supply. The idea may sound eccentric but kinetic energy, according to a Wall Street Journal report on these companies, is getting increasingly popular.

The idea draws on hydropower storage: that involves pushing water uphill and storing it until it is needed to power the turbines, when it is released downhill. On instead of water, these companies use gravity, essentially lifting and dropping heavy objects. Energy Vault uses bricks and says 20 brick towers could power up to 40,000 households for a period of 24 hours. Related: Oil Suppliers Slash Prices To Save Asian Market Share

Another company, in the UK, lifts and drops weights in abandoned mine shafts. 

Gravitricity, which last year ran a crowdfunding campaign that raised $978,000 (750,000 pounds), is using abandoned shafts to raise and lower weights of between 500 and 5,000 tons with a system of winches. According to the company, the system could be configured for between 1 and 20 MW peak capacity. The duration of power supply, however, is even more limited than Energy Vault’s, at 15 minutes to 8 hours.

The duration of power supply is an important issue. When the wind dies down and the sky is overcast, this could last more than a day as evidenced by the wind drought in the UK two years ago, when wind turbines were forced to idle for a week.


Gravity-base storage is one alternative to batteries, some of it cheaper than batteries, but for the time being, less reliable than batteries if we are thinking about a 100-percent renewable-powered grid. Another solution is thermal storage.

EnergyNest is one developer of thermal energy storage. It works by pumping a heated fluid along a system of pipes and storing it in a solid material. The heat flows into the material from top to bottom and is released into this material where it stays until it is needed again. Then, the flow gets reversed, with cold fluid (thermal oil or water) flowing from the bottom up, heating up in the process and exiting the storage system. Related: Restarted Saudi, Kuwaiti Oilfields To Pump 550,000 Bpd By End-2020

Then there is liquid air storage as an alternative to batteries. It works by separating the carbon dioxide and the oxygen from the nitrogen in the air and then storing this nitrogen in liquefied form. When needed to generate electricity, it is regasified. The process of liquefaction is powered by the excess electricity that needs to be stored and when a peak in demand requires more electricity generation, it is reheated and regasified, and used to power a turbine. According to experts, the process is not 100-percent efficient, with rates ranging from 25 percent to 70 percent.


Yet another potential alternative to batteries for energy storage is using geothermal energy to store heat and then releasing it to generate more electricity. The so-called sensitized thermal cells developed by researchers from the Tokyo Institute of Technology are technically batteries, as they use electrodes to move electrons. But on the flip side, it does not work with intermittent energy such as solar or wind. It taps the potential of geothermal energy, an underused renewable source.

Not all of these energy storage idea swill take off. Not all of them will prove viable enough to become widely adopted. Yet some alternatives to batteries will likely work well enough to provide an alternative to the dominant technology. Alternatives are important when you are aiming for 100-percent renewable electricity. 


Failing that, we could simply use our EV batteries as energy storage for excess power from solar and wind installations, as the International Renewable Energy Agency said earlier this month. While a strain on the grid when they charge, IRENA said, electric cars could juice up at the right time to take in surplus power and then release it back into the grid if that grid is a smart one. In 2050, around 14 terawatt-hours (TWh) of EV batteries would be available to provide grid services, compared to 9 TWh of stationary batteries, according to the agency. One way or another, slowly and with difficulty, we are heading into a much more renewable energy future.

The Future Of Lithium Batteries, According To Their Co-Inventor – A Podcast

Nearly all your devices run on lithium batteries. They have revolutionised the way we use, manufacture and charge our devices. Here’s a Nobel Prizewinner on his part in their invention – and their future.

British-born scientist M. Stanley Whittingham, of Binghamton University, was one of three scientists who won the 2019 Nobel Prize in Chemistry for their work developing lithium-ion batteries.

Maybe you know exactly what a lithium-ion battery is but even if you don’t, chances are you’re carrying one right now. They’re the batteries used to power mobile phones, laptops and even electric cars. 

When it comes to energy storage, they’re vastly more powerful than conventional batteries and you can recharge them many more times.

Their widespread use has driven global demand for the metal lithium – demand that Opposition Leader Anthony Albanese this week saidAustralia should do more to meet. 

Lithium ion batteries revolutionised the way we use, manufacture and charge our devices. They’re used to power mobile phones, laptops and even electric cars. 

The University of Queensland’s Mark Blaskovich, who trained in chemistry and penned this article about Whittingham’s selection for the chemistry Nobel Prize, sat down with the award-winner this week.

They discussed what the future of battery science may hold and how we might address some of the environmental and fire risks around lithium-ion batteries.

He began by asking M. Stanley Whittingham how lithium batteries differ from conventional, lead-acid batteries, like the kind you might find in your car.

New to podcasts?

Podcasts are often best enjoyed using a podcast app. All iPhones come with the Apple Podcasts app already installed, or you may want to listen and subscribe on another app such as Pocket Casts.

To listen on “Trust Me I’m An Expert” Follow the Link provided below).

Podcast on Trust Me I’m An Expert

Additional credits

Recording and production assistance by Thea Blaskovich

Kindergarten by Unkle Ho, from Elefant Traks.

Announcement of the Nobel Prize in Chemistry 2019

First Fully Rechargeable Carbon Dioxide Battery is Seven Times More Efficient Than Lithium Ion

CO2 Battery 1 Unmarked-Batteries-Public-Domain-via-Pxhere

Carbon Dioxide Battery is Seven Times More Efficient Than Lithium Ion

Lithium-carbon dioxide batteries are attractive energy storage systems because they have a specific energy density that is more than seven times greater than commonly used lithium-ion batteries. Until now, however, scientists have not been able to develop a fully rechargeable prototype, despite their potential to store more energy.

Researchers at the University of Illinois at Chicago are the first to show that lithium-carbon dioxide batteries can be designed to operate in a fully rechargeable manner, and they have successfully tested a lithium-carbon dioxide battery prototype running up to 500 consecutive cycles of charge/recharge processes.

Their findings are published in the journal Advanced Materials.

“Lithium-carbon dioxide batteries have been attractive for a long time, but in practice, we have been unable to get one that is truly efficient until now,” said Amin Salehi-Khojin, associate professor of mechanical and industrial engineering at UIC’s College of Engineering.

MOREExciting New Study Says That Crops Thrive Underneath Solar Panels—and the Panels Produce More Energy

Traditionally, when a lithium-carbon dioxide battery discharges, it produces lithium carbonate and carbon. The lithium carbonate recycles during the charge phase, but the carbon just accumulates on the catalyst, ultimately leading to the battery’s failure.


Lithium–CO2 batteries are attractive energy‐storage systems for fulfilling the demand of future large‐scale applications such as electric vehicles due to their high specific energy density.

“The accumulation of carbon not only blocks the active sites of the catalyst and prevents carbon dioxide diffusion, but also triggers electrolyte decomposition in a charged state,” said Alireza Ahmadiparidari, first author of the paper and a UIC College of Engineering graduate student.

Salehi-Khojin and his colleagues used new materials in their experimental carbon dioxide battery to encourage the thorough recycling of both lithium carbonate and carbon. They used molybdenum disulfide as a cathode catalyst combined with a hybrid electrolyte to help incorporate carbon in the cycling process.

CHECK OUT: This Revolutionary Blast Furnace Vaporizes Trash and Turns It into Clean Energy (Without Any Emissions)

Specifically, their combination of materials produces a single multi-component composite of products rather than separate products, making recycling more efficient.

“Our unique combination of materials helps make the first carbon-neutral lithium carbon dioxide battery with much more efficiency and long-lasting cycle life, which will enable it to be used in advanced energy storage systems,” Salehi-Khojin said.

This research was supported, in part, by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, and a grant from the National Science Foundation.

Reprinted from the University of Illinois-Chicago

Extreme weather is driving the energy storage boom – Could batteries become the new generators?

Extreme Weather 1_xkVnyv3rL7fkvkxCVeS7lA

Energy storage installations for homes and businesses — involving battery technology — are on the rise in areas where extreme weather threatens the electric power grid, such as flood-prone Houston, wildfire-stricken California and hurricane-ravaged Puerto Rico.

A sustained power outage can lead to serious consequences, such as loss of income and even death. Because of climate change, the frequency of these extreme weather events and outages will climb.

Traditionally, buildings would rely upon gas-powered diesel generators during outages. These generators have their own problems and do not necessarily help the electric grid become more resilient.

With recent technological changes, could batteries become the new generators?

Tracking sharp growth in the past year

Small-scale, so-called behind-the-meter energy storage accounted for 60% of battery capacity in the United States during the first quarter of this year.

Deployments grew 138% in the past year, driven in part by families and business leaders who are seeking resilience against power disruptions in our increasingly volatile climate.

When properly designed, electric energy storage can not only provide additional grid resilience, it can further minimize greenhouse gas and local air emissions compared with the conventional gas generators.

Vulnerable regions look to storage for relief

The race for storage is on:

  • In California, solar installation companies have been reporting a steady uptick in solar-plus-storage orders this year. All of the state’s large electric investor-owned utilities are implementing Public Safety Power Shutoff programs, which would de-energize an electric line and intentionally cause a blackout. The goal is to prevent wildfires in high-wind conditions when power lines are at risk of igniting a wildfire. As a result, a growing number of Californians with the economic capability to invest in solar-plus-storage are weighing this option.
  • In Puerto Rico, installations of such systems doubled after Hurricane Maria in 2017. Battery suppliers such as Tesla had difficulty keeping up with orders. Before Maria, only about 5% of solar installations Tesla did came with storage; today 95% do, Energywire reported.
  • And in a rural New Hampshire town where residents and business owners struggle with outages after ice storms and heavy snowfalls, a local utility is proposing to back up the town with energy storage batteries that may also save ratepayers money over time.

Energy storage incentives align

Falling costs and new deployment incentives are fueling record investments in energy storage. Analysists expect such investments to soar by $620 billion globally over the next two decades.

In the U.S., 15 states so far have adopted policies that make it easier or more affordable to invest in energy storage.

Coinciding with these market changes is a realization in states such as South Carolina — which until recently lagged in clean energy investments — that people and businesses in coastal areas are increasingly vulnerable to storms.

With widespread power outages from hurricanes Florence and Irma fresh in mind, the state recently passed legislation supporting solar and energy projects.

As more states help expand the market, it is important to start thinking of energy storage as a key strategy to make buildings cleaner and more grid resilient. The technology will only become more important to prevent outages during extreme weather events.

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.

    New discovery makes fast-charging, better performing lithium-ion batteries possible

    New Electrode 23c4a3_036cc463e8e9458d9a2070b7b7bb8c5c_mv2

    April –  2019 – Rensselaer Polytechnic Institute – Material Science

    Creating a lithium-ion battery that can charge in a matter of minutes but still operate at a high capacity is possible, according to research from Rensselaer Polytechnic Institute just published in Nature Communications. This development has the potential to improve battery performance for consumer electronics, solar grid storage, and electric vehicles.

    A lithium-ion battery charges and discharges as lithium ions move between two electrodes, called an anode and a cathode. In a traditional lithium-ion battery, the anode is made of graphite, while the cathode is composed of lithium cobalt oxide.

    These materials perform well together, which is why lithium-ion batteries have become increasingly popular, but researchers at Rensselaer believe the function can be enhanced further.

    “The way to make batteries better is to improve the materials used for the electrodes,” said Nikhil Koratkar, professor of mechanical, aerospace, and nuclear engineering at Rensselaer, and corresponding author of the paper. “What we are trying to do is make lithium-ion technology even better in performance.”

    Vanadium Sulfide download

    Vanadium disulfide – a promising new monolayer material for Li-ion batteries

    Koratkar’s extensive research into nanotechnology and energy storage has placed him among the most highly cited researchers in the world. In this most recent work, Koratkar and his team improved performance by substituting cobalt oxide with vanadium disulfide (VS2).

    “It gives you higher energy density, because it’s light. And it gives you faster charging capability, because it’s highly conductive. From those points of view, we were attracted to this material,” said Koratkar, who is also a professor in the Department of Materials Science and Engineering.

    Excitement surrounding the potential of VS2 has been growing in recent years, but until now, Koratkar said, researchers had been challenged by its instability–a characteristic that would lead to short battery life. The Rensselaer researchers not only established why that instability was happening, but also developed a way to combat it.

    The team, which also included Vincent Meunier, head of the Department of Physics, Applied Physics, and Astronomy, and others, determined that lithium insertion caused an asymmetry in the spacing between vanadium atoms, known as Peierls distortion, which was responsible for the breakup of the VS2 flakes. They discovered that covering the flakes with a nanolayered coating of titanium disulfide (TiS2)–a material that does not Peierls distort–would stabilize the VS2 flakes and improve their performance within the battery.

    “This was new. People hadn’t realized this was the underlying cause,” Koratkar said. “The TiS2 coating acts as a buffer layer. It holds the VS2 material together, providing mechanical support.”

    Once that problem was solved, the team found that the VS2-TiS2 electrodes could operate at a high specific capacity, or store a lot of charge per unit mass. Koratkar said that vanadium and sulfur’s small size and weight allow them to deliver a high capacity and energy density. Their small size would also contribute to a compact battery.

    When charging was done more quickly, Koratkar said, the capacity didn’t dip as significantly as it often does with other electrodes. The electrodes were able to maintain a reasonable capacity because, unlike cobalt oxide, the VS2-TiS2 material is electrically conductive.

    Koratkar sees multiple applications for this discovery in improving car batteries, power for portable electronics, and solar energy storage where high capacity is important, but increased charging speed would also be attractive.

    Rensselaer college-photo_3861

    Rensselaer Polytechnic Institute


    Vanadium disulfide flakes with nanolayered titanium disulfide coating as cathode materials in lithium-ion batteries Lu Li, Zhaodong Li, Anthony Yoshimura, Congli Sun, Tianmeng Wang, Yanwen Chen, Zhizhong Chen, Aaron Littlejohn, Yu Xiang, Prateek Hundekar, Stephen F. Bartolucci, Jian Shi, Su-Fei Shi, Vincent Meunier, Gwo-Ching Wang & Nikhil Koratkar Nature Communications volume 10, Article number: 1764 (2019)

    Rensselaer Polytechnic Institute

    #Batteries #Energy #MaterialScience

    Graphene-based ink may lead to printable energy storage devices

    Top) The salt-templated process of synthesizing graphene nanosheets into ink. (Bottom) The ink and printed demonstration. Credit: Wei et al. ©2019 American Chemical Society

    Researchers have created an ink made of graphene nanosheets, and demonstrated that the ink can be used to print 3-D structures. As the graphene-based ink can be mass-produced in an inexpensive and environmentally friendly manner, the new methods pave the way toward developing a wide variety of printable energy storage devices.

    The researchers, led by Jingyu Sun and Zhongfan Liu at Soochow University and the Beijing Graphene Institute, and Ya-yun Li at Shenzhen University, have published a paper on their work in a recent issue of ACS Nano.

    “Our work realizes the scalable and green synthesis of nitrogen-doped  nanosheets on a salt template by direct chemical vapor deposition,” Sun told “This allows us to further explore thus-derived inks in the field of printable energy storage.”

    As the scientists explain, a key goal in graphene research is the mass production of graphene with high quality and at low cost. Energy-storage applications typically require graphene in powder form, but so far production methods have resulted in powders with a large number of structural defects and chemical impurities, as well as nonuniform layer thickness. This has made it difficult to prepare high-quality graphene inks.

    In the new paper, the researchers have demonstrated a new method for preparing graphene inks that overcomes these challenges. The method involves growing nitrogen-doped graphene nanosheets over NaCl crystals using direct chemical vapor deposition, which causes molecular fragments of nitrogen and carbon to diffuse on the surface of the NaCl crystals. The researchers chose NaCl due to its natural abundance and low cost, as well as its water solubility.

    To remove the NaCl, the coated crystals are submerged in water, which causes the NaCl to dissolve and leave behind pure nitrogen-doped graphene cages. In the final step, treating the cages with ultrasound transforms the cages into 2-D nanosheets, each about 5-7 graphite layers thick.

    The resulting nitrogen-doped graphene nanosheets have relatively few defects and an ideal size (about 5 micrometers in side length) for printing, as larger flakes can block the nozzle.

    To demonstrate the nanosheets’ effectiveness, the researchers printed a wide variety of 3-D structures using inks based on the graphene sheets.

    Among their demonstrations, the researchers used the ink as a conductive additive for an  (vanadium nitride) and used the composite ink to print flexible electrodes for supercapacitors with high power density and good cyclic stability. 

    In a second demonstration, the researchers created a composite ink made of the graphene sheets along with binder material (polypropylene) for printing interlayers for Li−S batteries.

    Compared to batteries with separators made only of the conventional material, those made with the composite material exhibited enhanced conductivity, leading to an overall improvement in battery performance.

    “In the future, we plan to exploit the direct technique for the mass production of high-quality graphene powders toward emerging printable energy storage applications,” Sun said.

    More information: Nan Wei et al. “Scalable Salt-Templated Synthesis of Nitrogen-Doped Graphene Nanosheets toward Printable Energy Storage.” ACS Nano. DOI: 10.1021/acsnano.9b03157

    Journal information: ACS Nano

    %d bloggers like this: