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Manchester MBAs identify opportunities for graphene

Posted By Graphene Council, Monday, June 29, 2020
The International Business Consultancy Project is the capstone of the Full-time MBA. Our MBAs work in multinational teams to pitch for a client with a global business challenge, then undertake three months of full-time consultancy with international travel. This year, one team worked with the University's Graphene Engineering Innovation Centre (GEIC) to identify new opportunities in the energy storage market.

Graphene was first isolated in 2004 by two researchers at The University of Manchester, Professor Andre Geim and Professor Kostya Novoselov. Andre and Kostya won the Nobel Prize in Physics for their pioneering work. Graphene is the lightest, most conductable material on earth with potential applications across many fields - from medicine to energy. The project took our MBAs overseas to Germany, France, the USA and India. We caught up with them to find out more.

Why did you choose this client brief?

The Graphene Engineering Innovation Centre (GEIC) is an R&D facility at The University of Manchester, which focuses on driving the commercialisation of graphene and other 2D materials. The project aimed to provide a strategic market study to find potential market opportunities for GEIC in the Energy Storage Device (ESD) space (supercapacitors and batteries in particular).

We chose this project because it was very comprehensive: it included market research, partnership identification, financial modelling and projection. The team members could therefore utilise their different skill sets to contribute to the project. In addition, the energy storage device industry presented a new market for the team to explore and develop knowledge of.

How did you approach the brief?

The team used a 'bottom-up' approach instead of the traditional 'top down' methodology to analyse the key findings and provide recommendations. This idea came from our supervisor, Dr. Mike Arundale, who gave us a lot of support during the project. To be specific, the team produced a detailed case study of one specific company for each market segment, then made a projection for that segment and finally analysed the whole industry.

Which countries did you travel to and why?

Based on the secondary research, the team identified the USA, China, South Korea, Japan, India, Germany and France as the potential markets for GEIC to focus on and explore future partnership opportunities in. 45 interviews were held across Germany, France, the USA, China and India between February 6 and March 13, 2020. 

Due to the unexpected Coronavirus situation, in the end the team was only able to travel to the USA, India, Germany and France. This meant that 30 of the interviews were held face-to-face and 15 were conducted by conference call with Chinese, Japanese and South Korean companies.

What was the biggest challenge and what was the biggest achievement? 

 "At the initial stage, the biggest challenge was understanding the technical information and benefits of graphene. The biggest achievement was that we were able to understand the industry and reach the goal of finding potential partnerships for the client. It was a collaborative effort." - Lissete Flores, Peruvian

"The most challenging task was getting connections for primary research. My project was to search for partnerships for the client in three major markets: the USA, Europe and India. As we needed to build connections from scratch for face-to-face interviews or site visits, my team discussed how to ‘tackle’ interviewees strategically with the best professional practice in order to build professional relationships and get appointments for in-person interviews." 

"The biggest achievement was reaching out to potential partners for our client. Since our client's business is based on the licensing fee from partners, the potential deals are red blood being pumped to the heart of the business." - Pann Boonyavanich, Thai

"The biggest challenges were developing a good technical understanding of graphene as a 2D material and its numerous applications, which span multiple industries, and understanding the advantages of graphene and how it can be used in real-life applications. These elements were key to delivering the commercial aspects of the project. This became further challenging because the technology is quite nascent and there is not a lot of in-depth information available on the internet, which resulted in the team having to rely mostly on primary research."

"The biggest achievement was the team being able to successfully navigate the uncertainty brought on by the Covid-19 crisis and deliver on all the deliverables outlined in the project." - Ritwick Mukherjee, Indian

"For me, the biggest challenge was finding the relevant people to interview, getting them to agree to an interview and then fitting this into our travelling window. Some people were on annual leave and some could not meet with us for reasons related to Covid-19. Others did not reply till we were actually in the US, and a couple of companies worked with the US military and therefore most of their operational information was classified. Pann and I were on the east coast of the US and had to manage travelling and interviews in Boston, New York, Tennessee, Detroit and Chicago. Memorable journeys to interview potential partners include taking four flights in one day (a round trip from New York to Tennessee); and driving for six hours through a snowstorm to get to an interview in Chicago."

"The biggest achievement was realising during an interview that the company had synergies, problems or solutions that would match well with our client. It was very rewarding to be able to provide partnerships that would generate new revenue streams for our client and therefore justify their faith and investment in our team. Getting closer to each other and working well as a team was also a big achievement." - Timeyin Akerele, British-Nigerian

"Apart from the above mentioned by my team members, I also want to highlight that we had to change our interview plan entirely from China to Europe within just one week. We did the research again and identified Germany and France to replace the original destination, China, due to the unexpected Coronavirus situation. It was intensive to replan the interview travel and redo the budget, but it was also a valuable learning experience. This has motivated me to always be resilient when faced with uncertainties."

"The biggest achievements were, firstly, the team successfully helped the client find potential partners with detailed contacts for further discussion by using a new approach, the 'bottom-up' approach. Secondly, the team had a great chance to gain knowledge of the energy storage devices industry, and the value that advanced materials such as graphene can bring to the industry. Personally, I had no knowledge of this before." - Xingbo Wu, Chinese

What were the results and recommendations? 

The total market size of supercapacitor applications globally is worth around £2.27 billion in 2020, with a compound annual growth rate of ~20% between 2020-2030 and three key application industry segments: consumer electronics, automotive and power grid.

Companies that have an R&D gap that could be filled by graphene, in order to better meet customer demands, are potential partners for GEIC. For example, large manufacturers who lack supercapacitor product lines, or small manufacturers.

When targeting potential partnerships, the team recommended that GEIC should highlight its competitive position. GEIC is the only establishment offering capabilities in graphene, batteries, supercapacitors and biomedical fields, with a focus on both research and the commercialisation and scale-up of new technologies. 

How would you sum up your experience in three words?   

Lissete: Challenging - Teamwork - Fun

Pann: Dynamic - VUCA (volatility, uncertainty, complexity and ambiguity) - Exciting

Ritwick: Pushing - New - Frontiers

Timeyin: Amazing - Unpredictable - Teamwork

Xingbo: Uncertain - Unforgettable - United

Tags:  2D materials  Graphene  Graphene Engineering Innovation Centre  Lissete Flores  Pann Boonyavanich  Ritwick Mukherjee  Supercapacitor  Timeyin Akerele  University of Manchester  Xingbo Wu 

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Lightning in a (nano)bottle: new supercapacitor opens door to better wearable electronics

Posted By Graphene Council, Friday, June 12, 2020
Researchers from Skoltech, Aalto University and Massachusetts Institute of Technology have designed a high-performance, low-cost, environmentally friendly, and stretchable supercapacitor that can potentially be used in wearable electronics. The paper was published in the Journal of Energy Storage.

Supercapacitors, with their high power density, fast charge-discharge rates, long cycle life, and cost-effectiveness, are a promising power source for everything from mobile and wearable electronics to electric vehicles. However, combining high energy density, safety, and eco-friendliness in one supercapacitor suitable for small devices has been rather challenging.

"Usually, organic solvents are used to increase the energy density. These are hazardous, not environmentally friendly, and they reduce the power density compared to aqueous electrolytes with higher conductivity," says Professor Tanja Kallio from Aalto University, a co-author of the paper.

The researchers proposed a new design for a "green" and simple-to-fabricate supercapacitor. It consists of a solid-state material based on nitrogen-doped graphene flake electrodes distributed in the NaCl-containing hydrogel electrolyte. This structure is sandwiched between two single-walled carbon nanotube film current collectors, which provides stretchability. Hydrogel in the supercapacitor design enables compact packing and high energy density and allows them to use the environmentally friendly electrolyte.

The scientists managed to improve the volumetric capacitive performance, high energy density and power density for the prototype over analogous supercapacitors described in previous research. "We fabricated a prototype with unchanged performance under the 50% strain after a thousand stretching cycles. To ensure lower cost and better environmental performance, we used a NaCl-based electrolyte. Still the fabrication cost can be lowered down by implementation of 3D printing or other advanced fabrication techniques," concluded Skoltech professor Albert Nasibulin.

Tags:  Aalto University  Albert Nasibulin  Electronics  Graphene  Massachusetts Institute of Technology  Supercapacitor  Tanja Kallio 

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Supercapacitor promises storage, high power and fast charging

Posted By Graphene Council, Wednesday, May 6, 2020
A new supercapacitor based on manganese oxide could combine the storage capacity of batteries with the high power and fast charging of other supercapacitors, according to researchers at Penn State and two universities in China.

“Manganese oxide is definitely a promising material,” said Huanyu "Larry" Cheng, assistant professor of engineering science and mechanics and faculty member in the Materials Research Institute, Penn State. “By combining with cobalt manganese oxide, it forms a heterostructure in which we are able to tune the interfacial properties.”

The group started with simulations to see how manganese oxide’s properties change when coupled with other materials. When they coupled it to a semiconductor, they found it made a conductive interface with a low resistance to electron and ion transport. This will be important because otherwise the material would be slow to charge.

“Exploring manganese oxide with cobalt manganese oxide as a positive electrode and a form of graphene oxide as a negative electrode yields an asymmetric supercapacitor with high energy density, remarkable power density and excellent cycling stability,” according to Cheng Zhang, who was a visiting scholar in Cheng’s group and is the lead author on a paper published recently in Electrochimica Acta.

The group has compared their supercapacitor to others and theirs has much higher energy density and power. They believe that by scaling up the lateral dimensions and thickness, their material has the potential to be used in electric vehicles. So far, they have not tried to scale it up. Instead, their next step will be to tune the interface where the semiconducting and conducting layers meet for even better performance. They want to add the supercapacitor to already developed flexible, wearable electronics and sensors as an energy supply for those devices or directly as self-powered sensors.

Cheng Zhang is now an assistant professor at Minjiang University, China. The second Chinese university is Guizhou Education University. The paper is “Efficient Coupling of Semiconductors into Metallic MnO2@CoMn2O4 Heterostructured Electrode with Boosted Charge Transfer for High-performance Supercapacitors.”

Tags:  Cheng Zhang  Graphene  graphene oxide  Huanyu Larry Cheng  Minjiang University  Penn State  Supercapacitor 

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First Graphene makes headway in graphene development

Posted By Graphene Council, Tuesday, March 24, 2020
Advanced materials company First Graphene (FGR) has provided an update on its program to develop novel graphene hybrid materials.

In September 2019, First Graphene signed an exclusive licence agreement with the University of Manchester. This agreement allowed for the manufacture of hybrid-graphene materials by electrochemical processing.

Electrochemical processing can synthesise two valued product groups. These include metal oxide decorated materials with high capacitance for applications in super-capacitors and catalysis, and pristine graphene products for applications in electrical and thermal conductivity.

In October, the UK Engineering and Physical Sciences Council (EPSRC) funded the transfer the technology from university labs to First Graphene's labs.

Since then, First Graphene has successfully transferred the technology to its labs in Manchester. It has also completed two pilot trials at its manufacturing facility in Henderson, WA.

These trials demonstrated the synthesis and manufacture of metal oxide decorated materials and pristine graphene materials.

First Graphene is now testing the performance of these materials in energy storage and catalysis applications.

So far, testing has shown that prototype super-capacitor (coin cell) devices can be made with these materials.

Super-capacitors offer high-power density energy storage and can be charged or discharged fairly quickly. The demand for these devices is expected to grow by 20 per cent each year before reaching a revenue value of A$3.1 billion by 2022.

Unfortunately, however, COVID-19-related restrictions have delayed additional testing.

"We are disappointed that testing is being delayed due to current circumstances but will use this time to strengthen our end-user relationships," Managing Director Craig McGuckin said.

End-users in the aerospace, marine, electric vehicle and utility storage sectors have validated the need for high-performance super-capacitors.

In the meantime, the company is seeking government funding to develop a new supply chain for game-changing super-capacitor devices.

First Graphene is down 22.2 per cent and shares are trading for 7 cents each at 3:01 pm AEDT.

Tags:  Craig McGuckin  First Graphene  Graphene  Supercapacitor 

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Fast-charging, long-running, bendy energy storage breakthrough

Posted By Graphene Council, Wednesday, February 19, 2020
A new bendable supercapacitor made from graphene, which charges quickly and safely stores a record-high level of energy for use over a long period, has been developed and demonstrated by UCL and Chinese Academy of Sciences researchers.

While at the proof-of-concept stage, it shows enormous potential as a portable power supply in several practical applications including electric vehicles, phones and wearable technology.

The discovery, published today in Nature Energy, overcomes the issue faced by high-powered, fast-charging supercapacitors – that they usually cannot hold a large amount of energy in a small space.

First author of the study, Dr Zhuangnan Li (UCL Chemistry), said: “Our new supercapacitor is extremely promising for next-generation energy storage technology as either a replacement for current battery technology, or for use alongside it, to provide the user with more power.

“We designed materials which would give our supercapacitor a high power density – that is how fast it can charge or discharge – and a high energy density – which will determine how long it can run for. Normally, you can only have one of these characteristics but our supercapacitor provides both, which is a critical breakthrough.

“Moreover, the supercapacitor can bend to 180 degrees without affecting performance and doesn’t use a liquid electrolyte, which minimises any risk of explosion and makes it perfect for integrating into bendy phones or wearable electronics.”

A team of chemists, engineers and physicists worked on the new design, which uses an innovative graphene electrode material with pores that can be changed in size to store the charge more efficiently. This tuning maximises the energy density of the supercapacitor to a record 88.1 Wh/L (Watt-hour per litre), which is the highest ever reported energy density for carbon-based supercapacitors.

Similar fast-charging commercial technology has a relatively poor energy density of 5-8 Wh/L and traditional slow-charging but long-running lead-acid batteries used in electric vehicles typically have 50-90 Wh/L.

While the supercapacitor developed by the team has a comparable energy density to state-of-the-art value of lead-acid batteries, its power density is two orders of magnitude higher at over 10,000 Watt per litre.

Senior author and Dean of UCL Mathematical & Physical Sciences, Professor Ivan Parkin (UCL Chemistry), said: “Successfully storing a huge amount of energy safely in a compact system is a significant step towards improved energy storage technology. We have shown it charges quickly, we can control its output and it has excellent durability and flexibility, making it ideal for development for use in miniaturised electronics and electric vehicles. Imagine needing only ten minutes to fully-charge your electric car or a couple of minutes for your phone and it lasting all day.”

The researchers made electrodes from multiple layers of graphene, creating a dense, but porous material capable of trapping charged ions of different sizes. They characterised it using a range of techniques and found it performed best when the pore sizes matched the diameter of the ions in the electrolyte.

The optimised material, which forms a thin film, was used to build a proof-of-concept device with both a high power and high energy density.

The 6cm x 6cm supercapacitor was made from two identical electrodes layered either side of a gel-like substance which acted as a chemical medium for the transfer of electrical charge. This was used to power dozens of light-emitting diodes (LEDs) and was found to be highly robust, flexible and stable.

Even when bent at 180 degrees, it performed almost same as when it was flat, and after 5,000 cycles, it retained 97.8% of its capacity.

Senior author, Professor Feng Li (Chinese Academy of Sciences), said: “Over the next thirty years, the world of intelligent technology will accelerate, which will greatly change communication, transportation and our daily lives. By making energy storage smarter, devices will become invisible to us by working automatically and interactively with appliances. Our smart cells are a great example of how the user experience might be improved and they show enormous potential as portable power supply in future applications.”

Tags:  Chinese Academy of Sciences  Electric Vehicle  Energy Storage  Feng li  Graphene  Ivan Parkin  Supercapacitor  University College London  Zhuangnan Li 

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INST Mohali moving towards a globally competitive institution in Nano Science & Technology

Posted By Graphene Council, Monday, January 27, 2020
A cost-efficient and scalable method for graphene-based integrated on-chip micro supercapacitor, which is a miniaturized electrochemical storage device. A 'Nano-Spray Gel' that could be administered on-site for treatment of frostbite injuries and heal the wound; a novel low cost topical hemostatic device to address uncontrolled bleeding, purification devices for water and air respectively.

These are only some of the technologies rolled out by the Institute of Nanoscience and Technology (INST), one of the youngest autonomous institutions of the Department of Science and Technology. INST encourages all aspects of nanoscience and nanotechnology with major thrust in the areas of healthcare, agriculture, medical environment and energy with the ultimate goal to make a difference to society through nanoscience and technology.

INST brings together biologists, chemists, physicists, materials scientists, and engineers having an interest in nanoscience and technology. The scientists, having strengths in basic science together with more application-oriented minds from different backgrounds, work together by joining hands as a cohesive unit, under a congenial work environment, on a common platform apart from carrying out their individual research.

INST offers Ph.D. and Postdoctoral fellowships to students as part of its human resource development objective. Through its various activities, INST is committed to contribute significantly to the National Societal Programs like Swachh Bharat Abhiyan, Swasth Bharat, Smart Cities, Smart Villages, supporting the Strategic Sector, Make in India and Clean & Renewable Energy through scientific means and by generating processes, technologies and devices.

The institute encourages its scientists to publish their research in peer-reviewed international high impact journals which is reflected in their recent publication record in reputed journals like Energy and Environment, Nature Communication, JACS etc.INST supports industry’s through joint collaborations to address some of their needs like effluent management.

In addition, the institute imparts advanced training courses and laboratory techniques in the area of nanoscience, organizes important national and international level seminars and conferences, and supports the industry through joint industrial projects.INST is also promoting science amongst the young generation of the nation through its outreach program, especially for rural, remote and under-served schools by delivering talks to motivate the students to explore the world of science.

INST Mohali aims to emerge as India’s foremost research institution in Nano Science and Technology, which is globally competitive and contributes to the society through the application of nanoscience and nanotechnology in the field of healthcare, agriculture, energy and environment.

Tags:  Graphene  Institute of Nanoscience and Technology  nanotechnology  supercapacitor  water purification 

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First Graphene and Swinburne University Developing New battery Technology Using Graphene

Posted By Terrance Barkan, Wednesday, February 21, 2018

Advanced materials company, First Graphene Limited (“FGR” ) has announced an update on its work with the Swinburne University of Technology (SUT) on the development of a new energy storage technology using graphene, referring to their new product as the "BEST™ Battery".

 

While it is generally accepted that lithium-ion batteries are the state-of-the-art energy storage device available for consumer products today, they are not without their issues. In particular, there are examples where they have been the cause of fires in some instances. There is a vast number of companies and research institutions working to provide safer, more reliable and longer life batteries which utilise materials other than lithium-ion. Some of these involve the use of graphene. 

 

First Graphene, through its research and licencing agreements with Swinburne University of Technology, is pursuing a significantly different path to the development of the next generation of energy storage devices. Rather than trying to improve existing chemical battery technology, it is pioneering the field of advanced supercapacitors which have the potential to change the future for energy storage forever, particularly in handheld and consumer products.

 

Using the advanced qualities of graphene, First Graphene is developing the BEST™ Battery. This energy storage device promises to be chargeable in a fraction of the time and it will be fit for purpose for at least 10 times the life of existing batteries. It will be significantly safer and more environmentally friendly. All these improvements are made possible because the science relies on physics rather than chemical reactions, and on the remarkable properties of graphene materials. 

 

The table below provides an interesting comparison of key operating parameters of the BEST™ Battery alongside existing lithium-ion batteries and existing supercapacitors available in the market. What is particularly noteworthy is the 10x increase in the energy density expected for the BEST™ Battery, when compared with supercapacitors currently on sale in the market place, and the much lower cost per Wh. These features will provide great commercial advantages.

 

Table 1: Comparison between BEST™ Target development and existing Li Ion AA Batteries and an existing commercial Supercapacitor.

 

While the exact details of the design and construction of the BEST™ Battery must remain confidential for reasons of commercial security, First Graphene have disclosed the process of manufacturing the battery involves the use of lasers to create nanopores in graphene-based materials which achieve energy densities more than 10x as great as the pre-existing technology. Practical matters being addressed include the scaling up to the size of the battery from simple laboratory demonstrations of the effectiveness of the science, to devices which will be effective substitutes for batteries used in a wide range of hand held consumer products.

 

Recent Progress 

 

The first few months of the BEST™ Battery development project entailed the recruitment of additional, highly qualified research scientists and the acquisition of specialised equipment needed to prepare and manufacture the components of the BEST™ Battery.

 

Work has commenced on the improvement of many design aspects in order to optimise the configuration of the battery, with the ultimate objective being to develop a product suitable for mass scale production. At the same time, the methodology of making the battery is being subjected to continuous experimentation to improve the effectiveness and efficiency of the materials and processes used in the device. In addition, the pilot production line for building the BEST™ Battery prototype has been set up, which enables the manufacturing of the BEST™ Battery to meet industrial standards. 

 

Swinburne recently reported that a single layer of the BEST™ Battery prototype that made by the pilot production line was able to sustain an LED globe for a period of 15-20 minutes with only a few seconds of initial charge. This is a very significant outcome, auguring well for the ultimate product which is intended to comprise much more than 100 stacked layers of graphene sheets. 

 

The Ragone plot below tracks the continuing improvements in the performance of the BEST™ Battery.

 


 

Figure 1: Ragone Plot demonstrating the progress of the BEST™ Battery development toward its goal

 

Graphene-Based Flexible Smart Watch 

 

The research being undertaken also involves the development of flexible batteries for smart watches which can be incorporated into the watchband itself. These will be light-weight and flexible, they will be able to be recharged in 1-2 minutes, and they will be fit for purpose for many tens of thousands of cycles. Information will be displayed not only on the watch face, but also on the band itself.

Figure 2: Graphene Watch – Flexible Smart Watch concept

 

Target Markets 

 

While it is intended that the BEST™ Battery development program will eventually provide suitable substitutes for many devices which currently used flat pack and cylindrical batteries, it will also provide batteries for new, innovative purposes. The thin profile of the Battery, and its flexibility, will make it suitable for use in clothing. It could also be integrated into smart watch bands, as an example, rather than having a solid block configuration. It is already showing excellent ability to convert kinetic energy into stored energy due to the speed at which it can charge i.e. simple movement of shaking can recharge the Battery. 

 

Commenting on these progress, FGR’s Managing Director Craig McGuckin said:

 

“The demonstration of full scale commerciality of the BEST™ Battery will take time, but so far the results have been very encouraging. The science has been proved at laboratory scale and now we are advancing many aspects of materials used and design processes leading to the development and optimisation of production methodology. We are very pleased that Swinburne University of Technology has advised us that the pilot production line is a world first. We are confident that the advantages offered by our technology will bring revolutionary changes to how we use batteries in the future, with added safety, efficiencies and flexibilities. The BEST™ Battery will be a serious game changer”.

 

 

Tags:  Battery  First Graphene  Li-ion  Supercapacitor  Swinburne University 

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Graphene "Sandwich" Supercapcitor

Posted By Terrance Barkan, Wednesday, October 26, 2016

Ramakrishna Podila and Apparao Rao at the Clemson Nanomaterials Center, along with graduate students Jingyi Zhu and Anthony Childress, have discovered how to increase by five-fold the energy capacity of supercapacitors without sacrificing strength or durability using specially designed layers of atom-thick carbon sheets called graphene.

For the average person who may use but never see a supercapacitor, Clemson’s work means faster charging times, longer lives, a lighter power source than batteries, reduced dependency on fossil fuels, tons less air pollution and possibly lower energy prices.


Graphene sealed in a pouch with electrolytes makes a flexible supercapacitor.

Image Credit: Ashley Jones / Clemson University

 

In Geneva, Switzerland, supercapacitors power public buses two kilometers from a 15-second charge, and interest in Clemson’s research is building.

“A national research and development enterprise in India is interested in the Clemson supercapacitors and visited the Clemson Nanomaterials Institute twice. Negotiations for manufacturing supercapacitors to power a bus are in progress,” said Rao, the Robert A. Bowen Professor of Physics in the College of Science.

Other potential applications of supercapacitors are far-reaching, from regenerative braking in hybrid and electric vehicles to providing the burst of power needed to adjust the direction of turbine blades in changing wind conditions.

Capacitors, unlike batteries, deliver a lot of power over a very short time. Batteries deliver less power, but they store much more energy. Batteries store energy through a chemical reaction: ions in lithium ion batteries move between negative and positive electrodes.

“While the chemical reactions hold much energy, the ion motion in batteries is rather slow, leading to low power,” said Podila, an assistant professor in physics and astronomy in the College of Science.

Supercapacitors overcome this by storing ions on the surface of nanomaterials electrostatically, like socks sticking to towels coming out of a dryer.

Graphene, the nanomaterial used by the Clemson team, is ultrathin, a million times thinner than a human hair. It’s stronger than steel, flexible and lightweight; a sheet the size of a football field would weigh less than a gram.

“The high-surface area of graphene provides space for ion storage (high-energy) and the ions are always on the surface ready to race (high power),” Podila said. “The problem, however, has been to effectively use the high surface area.”

Often, Podila said, ions can’t access some of the spaces in nanomaterials due to lack of connectivity. Also, the electrons within some nanomaterials may limit the total energy of a supercapacitor through an effect called “quantum capacitance”.

The Clemson team created microscopic layers of graphene with nanometer-sized pores, then sandwiched them together. The pores not only open new channels for ions to access all the spaces in graphene, but they also increase the quantum capacitance.

Creating the pores in specific configurations increased storage capacity 150 percent. Then the researchers introduced two different electrolytes whose ions were smaller than the pores; one by 20 percent, the other by 55 percent.

The effect was like spreading mayo on soft, light, porous bread; the electrolytes oozed into the pores.

“Testing showed the electrolytes with the larger ions did not increase the capacity, but the smaller ions travel through the pores into untapped parts of graphene. The result was a 500 percent increase in capacity,” Zhu said.

Furthermore, the graphene retained its electrical and material properties; the bread, soaked with mayo, didn’t fall apart.

Zhu and Childress also fashioned graphene into thin, flexible electrodes and inserted them into a flexible pouch. They filled the pouch with the electrolyte containing the smaller ions and sealed it, creating a lightweight, flexible supercapacitor that withstood more than 10,000 charge-discharge cycles without any loss in performance.

Source: Clemson

Tags:  Batteries  Clemson  Energy Storage  Graphene  Supercapacitor 

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