Batteries that Really Keep Going and Going and Going …


U of Waterloo: Forget the graphite-based lithium batteries currently powering your devices. Next-generation batteries could last for decades. Really.

With a potential lifespan of 10 to 20 years, Professor Zhongwei Chen’s next-generation rechargeable batteries are set to put the Energizer Bunny to shame.

This battery could last 10 years, or even more than 20 years.Energizer_Bunny

Dr. Chen and his team are developing next-generation batteries and fuel cells. They are working on two types of batteries that are destined to be longer lasting and more efficient. One of these batteries is a rechargeable zinc battery that uses renewable energy, such as solar and wind. It could also be cost effective, which means that everyone could use it in the future.

Dr. Chen and his team are using novel materials to upgrade the traditional battery. He says that the key is to use silicon-based materials instead of graphite materials, which are currently being used in the commercial battery. Why? Silicon’s energy density is 10 times higher.

The result is a potential 150% energy density increase compared to its graphite-based lithium battery counterpart, which is currently being used to power electric cars and our cell phones. With the popularity of electric cars on the rise, companies such as Tesla and Panasonic are already looking to move beyond the limitations of the lithium battery.

Dr. Chen explains how he plans to solve the problems associated with the traditional battery as we move forward to meet the increased energy demands of the future.

MORE: Watch Our Current Battery Technology Project Video

A new company has been formed to exploit and commercialize the Next Generation Super-Capacitors and Batteries. The opportunity is based on Technology & Exclusive IP Licensing Rights from Rice University, discovered/ curated by Dr. James M. Tour, named “One of the Fifty (50) most influential scientists in the World today”

The Silicon Nanowires & Lithium Cobalt Oxide technology has been further advanced to provide a New Generation Battery that is:

 Energy Dense
 High Specific Power
 Affordable Cost
 Low Manufacturing Cost
 Rapid Charge/ Re-Charge
 Flexible Form Factor
 Long Warranty Life
 Non-Toxic
 Highly Scalable

Key Markets & Commercial Applications

 Motor Cycle/ EV Batteries
 Marine Batteries
 Drone Batteries and
 Power Banks
 Estimated $112B Market for Rechargeable Batteries by 2025

NREL Wins Award for Isothermal Battery Calorimeters – Measuring Battery Heat Levels and Energy Efficiency with 98% Accuracy – Video


NREL engineer Matthew Keyser holds a A123 battery module over the calorimeter he designed and built with the help of his staff.

” …. The IBCs can determine heat levels and battery energy efficiency with 98% accuracy and provide precise measurements through complete thermal isolation.”

NREL’s R&D 100 Award-winning Isothermal Battery Calorimeters (IBCs) are the only calorimeters in the world capable of providing the precise thermal measurements needed for safer, longer-lasting, and more cost-effective electric-drive vehicle (EDV) batteries. In order for EDVs hybrids (HEVs), plug-in hybrids (PHEVs), and all-electric vehicles (EVs) to realize ultimate market penetration, their batteries need to operate at maximum efficiency, performing at optimal temperatures in a wide range of driving conditions and climates, and through numerous charging cycles.

ibc_rotator_1Cutaway showing battery in the test chamber, heat flux gauges, isothermal fluid surrounding the test chamber, and outside container with insulation holding the bath fluid and the test chamber. Image: Courtesy of NETZSCH

 

NREL’s IBCs make it possible to accurately measure the heat generated by electric-drive vehicle batteries, analyze the effects of temperature on battery systems, and pinpoint ways to manage temperatures for the best performance and maximum life. Three models, the IBC 284, the Module IBC, and the Large-Volume IBC, make it possible to test energy devices at a full range of scales.

The World’s Most Precise Battery Calorimeters

Development of precisely calibrated battery systems relies on accurate measurements of heat generated by battery modules during the full range of charge/discharge cycles, as well as determination of whether the heat was generated electrochemically or resistively. The IBCs can determine heat levels and battery energy efficiency with 98% accuracy and provide precise measurements through complete thermal isolation. These are the first calorimeters designed to analyze heat loads generated by complete battery systems.

This video describes NREL’s R&D 100 Award-winning Isothermal Battery Calorimeters, the only calorimeters in the world capable of providing the precise thermal measurements needed for safer, longer-lasting, and more cost-effective electric-drive vehicle batteries.

Calorimeter Specifications
Specifications IBC 284 (Cell) Module IBC Large-Volume IBC (Pack)
Maximum Voltage (Volts) 50 500 600
Sustained Maximum Current (Amps) 250 250 450
Excursion Currents (Amps) 300 300 1,000
Volume (liters) 9.4 14.7 96
Maximum Dimensions (cm) 20.3 x 20.3 x 15.2 35 x 21 x 20 60 x 40 x 40
Operating Temperature (C) -30 to 60 -30 to 60 -40 to 100
Maximum Constant Heat Generation (W) 50 150 4,000

Working with Industry to Fine-Tune Energy Storage Designs

The IBCs’ capabilities make it possible for battery developers to predict thermal performance before installing batteries in vehicles. Manufacturers use these metrics to compare battery performance to industry averages, troubleshoot thermal issues, and fine-tune designs.

NREL in partnership with NETSCH Instrument North America and with support from the U.S. Department of Energy is using IBCs to help industry design better thermal management systems for EDV battery cells, modules, and packs. The U.S. Advanced Battery Consortium (USABC) and its partners rely on NREL for precise measurement of energy storage devices’ heat generation and efficiency under different states of charge, power profiles, and temperatures.

Experts Outline Pathway for Generating Up to Ten (10) Terawatts of Power from Sunlight by 2030: NREL – GA SERI


NREL IV energy-resources-renewables-fossil-fuel-uranium

The annual potential of solar energy far exceeds the world’s energy consumption, but the goal of using the sun to provide a significant fraction of global electricity demand is far from being realized.

Scientists from the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), their counterparts from similar institutes in Japan and Germany, along with researchers at universities and industry, assessed the recent trajectory of photovoltaics and outlined a potential worldwide pathway to produce a significant portion of the world’s electricity from solar power in the new Science paper, Terawatt-Scale Photovoltaics: Trajectories and Challenges.NREL I download

Fifty-seven experts met in Germany in March 2016 for a gathering of the Global Alliance of Solar Energy Research Institutes (GA-SERI), where they discussed what policy initiatives and technology advances are needed to support significant expansion of solar power over the next couple of decades.

“When we came together, there was a consensus that the global PV industry is on a clear trajectory to reach the multi-terawatt scale over the next decade,” said lead author Nancy Haegel, director of NREL’s Materials Science Center. “However, reaching the full potential for PV technology in the global energy economy will require continued advances in science and technology. Bringing the global research community together to solve challenges related to realizing this goal is a key step in that direction.”

NREL III pv global

Photovoltaics (PV) generated about 1 percent of the total electricity produced globally in 2015 but also represented about 20 percent of new installation. The International Solar Alliance has set a target of having at least 3 terawatts – or 3,000 gigawatts (GW) – of additional solar power capacity by 2030, up from the current installed capacity of 71 GW. But even the most optimistic projections have under-represented the actual deployment of PV over the last decade, and the GA-SERI paper discusses a realistic trajectory to install 5-10 terawatts of PV capacity by 2030.

Reaching that figure should be achievable through continued technology improvements and cost decreases, as well as the continuation of incentive programs to defray upfront costs of PV systems, according to the Science paper, which in addition to Haegel was co-authored by David Feldman, Robert Margolis, William Tumas, Gregory Wilson, Michael Woodhouse, and Sarah Kurtz of NREL.

GA-SERI’s experts predict 5-10 terawatts of PV capacity could be in place by 2030 if these challenges can be overcome:

  • A continued reduction in the cost of PV while also improving the performance of solar modules
  • A drop in the cost of and time required to expand manufacturing and installation capacity
  • A move to more flexible grids that can handle high levels of PV through increased load shifting, energy storage, or transmission
  • An increase in demand for electricity by using more for transportation and heating or cooling
  • Continued progress in storage for energy generated by solar power.

The Fraunhofer Institute for Solar Energy (Germany), the National Institute of Advanced Industrial Science and Technology (Japan), and the National Renewable Energy Laboratory (United States) are the member institutes of GA-SERI, which was founded in 2012.

NREL is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for the Energy Department by The Alliance for Sustainable Energy, LLC.

New battery coating could improve performance of smart phones and electric vehicles by 10X – But could still have Fire Safety Issues



High performing lithium-ion batteries are a key component of laptops, smart phones, and electric vehicles. Currently, the anodes, or negative charged side of lithium ion batteries, are generally made with graphite or other carbon-based materials.

But, the performance of carbon based materials is limited because of the weight and energy density, which is the amount of energy that can be stored in a given space. As a result, a lot of research is focused on lithium-metal anodes.

The success of lithium metal anodes will enable many battery technologies, including lithium metal and lithium air, which can potentially increase the capacity of today’s best lithium-ion batteries five to 10 times. That would mean five to 10 times more range for electric vehicles and smartphone batteries lasting five to 10 times more time. Lithium metal anodes are also lighter and less expensive.

The problem with lithium ion batteries made with metal is that during charge cycles they uncontrollably grow dendrites, which are microscopic fibers that look like tree sprouts. The dendrites degrade the performance of the battery and also present a safety issue because they can short circuit the battery and in some cases catch fire.

A team of researchers at the University of California, Riverside has made a significant advancement in solving the more than 40-year-old dendrite problem. Their findings were just published in the journal Chemistry of Materials (“In Situ Formation of Stable Interfacial Coating for High Performance Lithium Metal Anodes”).

Methyl Viologen Process


These are illustrations of the design principles of using methyl viologen to form a stable coating to allow the stable cycling of lithium metal. (Image: UC Riverside) (click on image to enlarge)

The team discovered that by coating the battery with an organic compound called methyl viologen they are able to stabilize battery performance, eliminate dendrite growth and increase the lifetime of the battery by more than three times compared to the current standard electrolyte used with lithium metal anodes.

“This has the potential to change the future,” said Chao Wang, an adjunct assistant professor of chemistry at UC Riverside who is the lead author of the paper. “It is low cost, easily manipulated and compatible with the current lithium ion battery industry.”

The researchers designed a new strategy to form a stable coating to enhance the lifetime of lithium-metal anodes. They used methyl viologen, which has been used in other applications because of its ability to change color when reduced.

The methyl viologen molecule used by the researchers can be dissolved in the electrolytes in the charged states. Once the molecules meet the lithium metal, they are immediately reduced to form a stable coating on top of the metal electrode.

By adding only .5 percent of viologen into the electrolyte, the cycling lifetime can already be enhanced by three times. In addition, methyl viologen is very low in cost and can easily be scaled up.

The stable operation of lithium metal anodes, which the researchers have achieved with the addition of methyl viologen, could enable the development of next generation high-capacity batteries, including lithium metal batteries and lithium air batteries.

Wang cautioned that while the coating improves battery performance, it isn’t a way to prevent batteries from catching fire.

Source: University of California – Riverside

A battery prototype powered by atmospheric nitrogen


Artistic illustration of Zhang and colleagues’ proof-of-concept experiment, which successfully implements a reversible nitrogen cycle based on rechargeable Li-N2 batteries with promising electrochemical faradic efficiency. Credit: Zhang et. al.




As the most abundant gas in Earth’s atmosphere, nitrogen has been an attractive option as a source of renewable energy. 

But nitrogen gas—which consists of two nitrogen atoms held together by a strong, triple covalent bond—doesn’t break apart under normal conditions, presenting a challenge to scientists who want to transfer the chemical energy of the bond into electricity.

In the journal Chem on April 13, researchers in China present one approach to capturing atmospheric nitrogen that can be used in a battery.

The “proof-of-concept” design works by reversing the chemical reaction that powers existing lithium-nitrogen batteries
Instead of generating energy from the breakdown of lithium nitride (2Li3N) into lithium and nitrogen gas, the researchers’ battery prototype runs on atmospheric nitrogen in ambient conditions and reacts with lithium to form lithium nitride. Its energy output is brief but comparable to that of other lithium-metal batteries.




“This promising research on a nitrogen fixation battery system not only provides fundamental and technological progress in the energy storage system but also creates an advanced N2/Li3N (nitrogen gas/lithium nitride) cycle for a reversible nitrogen fixation process,” says senior author Xin-Bo Zhang, of the Changchun Institute of Applied Chemistry, part of the Chinese Academy of Sciences
“The work is still at the initial stage. More intensive efforts should be devoted to developing the battery systems.”

More information: Chem, Ma and Bao et al.: “Reversible Nitrogen Fixation Based on Rechargeable Lithium-Nitrogen Battery for Energy Storage” 

BEYOND LITHIUM PROJECTS: TESLA’S PARTNER PANASONIC HINTS AT ELECTRIC VEHICLE BATTERY IMPROVEMENTS


CNT Battery MjU2NDIyMQ

Lithium-ion batteries represent a landmark technology that has made the current generation of electric vehicles possible. However, the day of their demise, while it still lies years in the future, is within view. Lithium-ion chemistries have a certain maximum energy density, dictated by those pesky laws of physics, and today’s batteries are not so far from that theoretical maximum. If drivers keep demanding longer ranges and faster charging times, then a better technology will have to be found.

Above: Panasonic’s 18650 lithium-ion battery cell used in the Tesla Model S and X (Image: Daily Sabah)

Safety is also an issue. The spectacular explosions and fireballs that some documentary-makers revel in are not the norm (when was the last time your phone or computer caught fire?), but Li-ion batteries do have to be handled carefully, and necessary safety features add complexity and cost to battery packs. A new chemistry that is safer could also prove to be cheaper.

Researchers around the world are working on “beyond lithium” projects, and the past year has seen several significant breakthroughs. Of course, advances in the lab take years to make their way to the marketplace, but if and when one of these promising technologies can be commercialized, we could see game-changing improvements in the performance and cost of EVs.

One technology that’s been getting a tremendous amount of attention from researchers is the solid-state battery, which uses a solid electrolyte instead of the liquid electrolyte used today. Solid-state batteries could theoretically have double the energy density of current batteries, and last several times longer. They also use a non-flammable electrolyte – usually glass, polymer, or a combination – so they would eliminate the safety issues that plague Li-ion cells.

Read About: Lithium-ion battery inventor (Dr. John Goodenough – UT Ausitn – introduces new technology for fast-charging, noncombustible batteries – Is it “Goodenough?”

Above: Lithium-ion battery vs. solid state battery (Image: Toyota)

Lithium-air batteries likewise could offer far greater energy density – maybe as much as 10 times more – but they suffer from poor cycle life. In 2015, Cambridge scientists wowed the battery world with an announcement that they had demonstrated a highly efficient and long-lasting lithium-oxygen battery. Alas, researchers from several universities and national labs have since been unable to duplicate the original results.

Other promising battery chemistries use other elements in place of lithium. Sodium batteries powered Jules Verne’s futuristic submarine in “20,000 Leagues Under the Sea.” More recently, in 2015, researchers created a prototype sodium-ion battery in the industry-standard 18650 cylindrical format.

According to a recent article in the Nikkei Asian Review, battery research has seen a big shift in recent years. At one time, nearly half of the presentations at the Battery Symposium in Japan were about fuel cells and Li-ion battery cathode materials. But since 2012, these topics have been supplanted by presentations about solid-state, lithium-air and non-lithium batteries.

Above: How a lithium-air battery works (Image: Money Inc)

Toyota has been focusing on solid-state and Li-air batteries. At the latest Battery Symposium, battery researcher Shinji Nakanishi discussed a scenario for transitioning from Li-ion batteries to solid-state and then Li-air batteries. “We want our electric cars to go 500 km” on a single charge, he said. “And for this, we want rechargeable batteries that can generate 800 to 1,000 watt-hours per liter.” That would be two to three times the energy density of today’s best Li-ion batteries.

Panasonic, Tesla’s battery supplier, is also taking a hard look at solid-state technology. “We think the existing technology can still extend the energy density of Li-ion batteries by 20% to 30%,” President Kazuhiro Tsuga told Nikkei. “But there is a trade-off between energy density and safety. So if you look for even more density, you have to think about additional safety technology as well. Solid-state batteries are one answer.”

Engineers have been pushing the limits of Li-ion technology for decades. Today’s best Li-ion cells can reach an energy density of about 300 watts per kilogram, *** which is getting close to the theoretical maximum. “Existing Li-ion batteries still have room to improve their energy density because you can raise the density by introducing a nickel-based cathode material, so you can expect the batteries will still be used in the next few years,” said battery expert Naoaki Yabuuchi of Tokyo Denki University. He expects lithium-ion technology to reach its limits around 2020.

Above: Tesla Model X on display at Panasonic’s booth at CES (Image: Business Wire)

Is Tesla working on any of these post-lithium chemistries? It would be strange if they were not. We know that the company is constantly evaluating new battery technologies. “Tesla has one of the largest cell characterization laboratories in the world – we have just about every cell you can imagine on test,” Tesla Product Planner Ted Merendino told me back in 2013. However, both Elon Musk and JB Straubel have said that so far, they’ve seen no viable replacement for lithium-ion, and believe me, they’ve been asked the question many times.

Tesla Model 3hqdefault“We have yet to see even a single example… of a cell working at the laboratory level that is better than the one that we have, or the ones that we expect to come out with,” said Elon Musk in 2014. Now, the way I parse this statement, he isn’t saying that there’s no improved battery technology in the offing – on the contrary, he’s saying that Tesla will be the one to develop it.

When Model 3 was announced, some EV-watchers opined that, in order to deliver the new vehicle at the desired price point, Tesla would need to make a major battery breakthrough. In the event, Tesla has developed a new battery for Model 3, but it looks more like an incremental improvement than a paradigm shift. The new 2170 cell, which is now being produced at the Gigafactory, is slightly larger than the trusty 18650, and can store more energy. According to Elon Musk, it’s “the highest energy density cell in the world, and also the cheapest.” Advances in the way the cells are assembled into modules and packs are also expected to yield a significant reduction in battery costs.

Above: Tesla’s battery pack in the floorpan of the Model S (Image: First Reporter)

So, it appears that lithium will continue its reign for a few more years at least. However, the post-lithium Holy Grail is still out there, and as likely as not, the knights of Tesla’s round table will be the ones to bring it home. Battery superstar Jeff Dahn and his colleagues aren’t working for Tesla just to make speeches at conferences. It’s entirely possible that, at some super-secret facility in California or Nevada, test mules are being powered by solid-state or lithium-air batteries even as we speak.

*** New Li-Io Technology Reports 400-500 Wh/kg with a $200/ kWh Cost

Cathode material with high energy density for all-solid lithium-ion batteries



Fig. 1. Charge/discharge curves of the new cathode material Black line: charge curve. Red line: discharge curve. The new material can operate at charge/discharge voltages of over 5V, which is beyond the limits of conventional lithium secondary batteries.

FDK Corporation and Fujitsu Laboratories today announced that they have jointly developed lithium cobalt pyrophosphate (Li2CoP2O7), which has high energy density, for the cathode material of all-solid lithium-ion batteries (“all-solid-state batteries”). 

This material enables the development of all-solid-state batteries with higher voltage and higher capacity. In recent years, the specifications required for batteries are becoming increasingly diverse, and, in particular, there is increasing interest in high energy density and safety performance. 

While there is active progress on improving lithium-ion and other existing batteries, development work is advancing on various types of next-generation batteries with the potential to exceed the performance of existing batteries, and all-solid-state batteries are attracting attention as next-generation batteries with superior safety performance.

FDK is working on the development of all-solid-state batteries, with such characteristics as high energy density, superior safety performance, and long battery life. 

The energy of a battery is a function of its voltage and capacity, and the development of an electrode material with high voltage and high capacity is required to create a battery with high energy density. 

In the process of developing an all-solid-state battery, through the use of FDK’s Computer Aided Engineering (CAE) technology and Fujitsu Laboratories’ materials formation technologies, FDK and Fujitsu Laboratories succeeded in developing the cathode material lithium cobalt pyrophosphate (Li2CoP2O7) for all-solid-state batteries. 

The material has approximately1.5 times the energy density of existing cathode materials for lithium-ion batteries.

Through computational physics, FDK and Fujitsu Laboratories have found that this material, when applied to all-solid-state batteries, is capable of operating with twice the energy density of existing cathode materials used in lithium-ion batteries. 

While working to further raise the performance of this material, the companies will continue development with the aim of an early market launch of a compact and safe all-solid-state battery that can be used in IoT applications, wearables, and mobile devices. 

This material and technology will be exhibited at the FDK booth during BATTERY JAPAN 2017 (8th international rechargeable battery expo) being held from March 1 to 3, 2017, at Tokyo Big Sight.

Cathode material with high energy density for all-solid lithium-ion batteries


Fig. 2. Comparison of the energy densities of the new cathode material versus conventional cathode materials. Credit: Fujitsu

New approach may accelerate design of high-power batteries



New approach may accelerate design of high-power batteriesElectric vehicles plug in to charging stations. New research may accelerate discovery of materials used in electrical storage devices, such as car batteries. Credit: Shutterstock

Research led by a Stanford scientist promises to increase the performance of high-power electrical storage devices, such as car batteries.

 

In work published this week in Applied Physics Letters, the researchers describe a mathematical model for designing new materials for storing electricity. The model could be a huge benefit to chemists and materials scientists, who traditionally rely on trial and error to create new materials for batteries and capacitors. Advancing new materials for energy storage is an important step toward reducing carbon emissions in the transportation and electricity sectors.

“The potential here is that you could build batteries that last much longer and make them much smaller,” said study co-author Daniel Tartakovsky, a professor in the School of Earth, Energy & Environmental Sciences. 
“If you could engineer a material with a far superior storage capacity than what we have today, then you could dramatically improve the performance of batteries.”

Lowering a barrier
One of the primary obstacles to transitioning from fossil fuels to renewables is the ability to store energy for later use, such as during hours when the sun is not shining in the case of solar power. Demand for cheap, efficient storage has increased as more companies turn to renewable energy sources, which offer significant public health benefits.

Tartakovsky hopes the new materials developed through this model will improve supercapacitors, a type of next-generation energy storage that could replace rechargeable batteries in high-tech devices like cellphones and electric vehicles. Supercapacitors combine the best of what is currently available for energy storage – batteries, which hold a lot of energy but charge slowly, and capacitors, which charge quickly but hold little energy. The materials must be able to withstand both high power and high energy to avoid breaking, exploding or catching fire.

“Current batteries and other storage devices are a major bottleneck for transition to clean energy,” Tartakovsky said. “There are many people working on this, but this is a new approach to looking at the problem.”

 
The types of materials widely used to develop energy storage, known as nanoporous materials, look solid to the human eye but contain microscopic holes that give them unique properties. Developing new, possibly better nanoporous materials has, until now, been a matter of trial and error – arranging minuscule grains of silica of different sizes in a mold, filling the mold with a solid substance and then dissolving the grains to create a material containing many small holes. 

The method requires extensive planning, labor, experimentation and modifications, without guaranteeing the end result will be the best possible option.

“We developed a model that would allow materials chemists to know what to expect in terms of performance if the grains are arranged in a certain way, without going through these experiments,” Tartakovsky said. “This framework also shows that if you arrange your grains like the model suggests, then you will get the maximum performance.”

Beyond energy
Energy is just one industry that makes use of nanoporous materials, and Tartakovsky said he hopes this model will be applicable in other areas, as well.

“This particular application is for electrical storage, but you could also use it for desalination, or any membrane purification,” he said. “The framework allows you to handle different chemistry, so you could apply it to any porous materials that you design.”

Tartakovsky’s mathematical modeling research spans neuroscience, urban development, medicine and more. As an Earth scientist and professor of energy resources engineering, he is an expert in the flow and transport of porous media, knowledge that is often underutilized across disciplines, he said.
 Tartakovsky’s interest in optimizing battery design stemmed from collaboration with a materials engineering team at the University of Nagasaki in Japan.
“This Japanese collaborator of mine had never thought of talking to hydrologists,” Tartakovsky said. “It’s not obvious unless you do equations – if you do equations, then you understand that these are similar problems.”

 
More information: Xuan Zhang et al. Optimal design of nanoporous materials for electrochemical devices, Applied Physics Letters (2017). DOI: 10.1063/1.4979466

Provided by: Stanford University

Nanotube-based Li-ion Batteries Can Charge to Near Maximum in Two Minutes but …


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Nanotube-based Li-ion Batteries Can Charge to Near Maximum in Two Minutes … but could our current grid system handle an ‘en masse’ switch to EV’s?

The prospects for ubiquitous all-electric vehicles (EVs) powered by lithium-ion (Li-ion) batteries took a bit of a hit back in 2010, when then U.S. Secretary of Energy Steven Chu addressed the United Nations Climate Change Conference in Cancun and suggested that, for battery powered cars to replace those powered by fossil fuels, some pretty significant improvements would need to be made to current technology.

Chu said at the time: “It will take a battery, first that can last for 15 years of deep discharges. You need about five as a minimum, but really six- or seven-times higher storage capacity and you need to bring the price down by about a factor of three.” Chu suggested it might take another five years before such a battery would be developed, and he was almost exactly right in his prediction.

Researchers at the Nanyang Technology University (NTU) in Singapore have achieved at least some of those criteria by developing a Li-ion battery capable of 20 years of deep discharges, more than 10 times that of existing Li-ion batteries.

In addition to longer battery life, the new battery design can be charged up quickly so that it can reach 70 percent of its maximum charge in just two minutes.

These features tick at least two of the metrics that Chu and others have indicated are key to making all-EVs compete with those running on fossil fuels. This would mean that EV owners would not have to spend roughly $5000 every two years for a completely new set of batteries. It could also allow for a quick stop of just a couple of minutes to significantly increase the driving range of the vehicle.

The key to the new Li-ion battery is the replacement of graphite at the anode with nanotubes synthesized from titanium dioxide. This is a departure from a lot of recent work toward improved anodes; other research teams have been using nanostructured silicon in place of graphite.

“With our nanotechnology, electric cars would be able to increase their range dramatically with just five minutes of charging, which is on par with the time needed to pump petrol for current cars,” said Chen Xiaodong, an associate professor at NTU Singapore, in a press release.

The new nanotube material, which is described in the journal Advanced Materials, is produced relatively easily, according to the researchers, by taking titanium dioxide nanoparticles and mixing them with sodium hydroxide. The real key to getting the long titanium dioxide nanotubes the nanoparticles yield is conducting the stirring process at the right temperature.

The technology has been patented and has been licensed by a company that says it could get a new generation of fast-charging batteries to market in two years.

While battery life and recharging have been significantly improved with the new battery design, it’s not clear that new batteries have a longer charge life, or what is known as gravimetric energy density (the amount of energy stored per unit mass). Instead, they have improved Li-ion’s relatively weak gravimetric power density (the maximum amount of power that can be supplied per unit mass) by eliminating the additives that are used to bind the electrodes to the anode. This allows the battery to transfer electrons and ions in and out of the battery more quickly. This translates into batteries that will last about the same amount of time on a charge as today’s current batteries, but can be charged up to near maximum very quickly.

NTU professor Rachid Yazami, who was the co-inventor of the lithium-graphite anode 34 years ago but not involved in this most recent research, has noted the significant improvement to Li-ion batteries this work represents.

Yazami said: “There is still room for improvement and one such key area is the power density—how much power can be stored in a certain amount of space—which directly relates to the fast charge ability. Ideally, the charge time for batteries in electric vehicles should be less than 15 minutes, which Prof Chen’s nanostructured anode has proven to do.”

Fern-Inspired Energy Storage Could Further Solar Power


fernThe breakthrough electrode prototype (right) can be combined with a solar cell (left) for on-chip energy harvesting and storage. Credit: RMIT University

A new type of electrode may help researchers finally solve one of the challenges preventing solar power from becoming a total energy solution.

RMIT University researchers believe a new graphene-based prototype— which is inspired by the structure of fern leaves— could boost the capacity of existing integrable storage by 3,000 percent and open a new path to the development of flexible thin film all-in-one solar capture and storage.

This advancement may lead to self-powering smart phones, laptops, cars and buildings.

The electrode is designed to work with supercapacitors, which can charge and discharge power significantly faster than conventional batteries. Supercapacitors have been combined with solar in the past, but their wider use as a storage solution is restricted because of their limited capacity.

The fractal design reflected the self-repeating shape of the veins of the western swordfern—Polystichum munitum—native to western North America.

RMIT’s Professor Min Gu explained how the prototype is based on the fern leaves.

RMIT images“The leaves of the western swordfern are densely crammed with veins, making them extremely efficient for storing energy and transporting water around the plant,” Gu, the leader of the Laboratory of Artificial Intelligence Nanophotonics and associate deputy vice-chancellor for Research Innovation and Entrepreneurship at RMIT, said in a statement.

Gu explained that the electrode is based on self-replicating fractal shapes and the researchers used the naturally-efficient design to improve solar energy storage at a nano level.

“The immediate application is combining this electrode with supercapacitors, as our experiments have shown our prototype can radically increase their storage capacity—30 times more than current capacity limits,” Gu said. “Capacity-boosted supercapacitors would offer both long-term reliability and quick-burst energy release for when someone wants to use solar energy on a cloudy day for example—making them ideal alternatives for solar power storage.”

Solar energy storage is an emerging technology that can promote the solar energy as the primary source of electricity. Recent developments of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features and consequent readiness for on-chip integration.

According to the study, the new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path.

The researchers combined the fractal-enabled laser-reduced graphene electrodes with supercapacitors to hold the stored charge for longer with minimal leakage.

Ph.D. researcher Litty Thekkekara explained that there are many applications for the prototype.

 “Flexible thin film solar could be used almost anywhere you can imagine, from building windows to car panels, smart phones to smart watches. We would no longer need batteries to charge our phones or charging stations for our hybrid cars. With this flexible electrode prototype we’ve solved the storage part of the challenge, as well as shown how they can work with solar cells without affecting performance,” she said.

“Now the focus needs to be on flexible solar energy, so we can work towards achieving our vision of fully solar-reliant, self-powering electronics.”

The study was published in Scientific Reports.