As Europe’s Graphene Flagship enters its third year, we highlight how the programme is supporting the commercialization of 2D materials through Graphene Connect – a series of interactive workshops that bring industry and academia together.
“I think the Graphene Connect workshop we attended was a great opportunity to measure the pulse on the applications,” said Amer Ali, CEO of Graphensic AB – a Swedish company producing graphene on silicon carbide. “At the event, we got in touch with skilled researchers and industry incumbents who were genuinely interested in what we do.”
Kostas Kostarelos, who leads the Nanomedicine Lab at the University of Manchester, UK, was a keynote speaker at Graphene Connect’s most recent workshop, which took place in February and showcased opportunities for 2D materials in biomedical technology. “The workshops are so important because they help to give companies a better understanding of graphene and how it can shape their roadmap going forward,” he explained.
More workshops planned for 2016: the organizing team is in the process of finalizing the next graphene connect event and will be announcing full details shortly on their website.
Applications discussed at the February workshop included smart clothes, sensor systems, wearables, packaging, electrodes and other ways that graphene can be used within the body. The events also provide the opportunity for a wider conversation on 2D materials.
“I wanted to understand more about the ‘translational potential’ and associated risk of graphene as well as the medical applications,” added Daniel Chew, Director of Neural Interfaces for GlaxoSmithKline. “Attending Graphene Connect helped to answer a lot of my questions and it was really good to see a wide interest in graphene from different industry sectors.”
The first Graphene Connect event took place in 2014, as part of Graphene Week, and themes covered so far by the workshop series include – nanocomposites, sensors, energy, optoelectronics and photonics, materials and production, investment opportunities and, as mentioned above, biomedical technology.
How can 2D materials help mobile device makers and equipment providers to upgrade their core products and grow their business in emerging markets such as wearable technology and the internet of things (IoT)? Visitors at this year’s Mobile World Congress (MWC) will have the chance to find out thanks to the Graphene Pavilion – a live demo space dedicated to 2D materials that makes its debut at the 2016 show (22-25 Feb). Applications on the radar include better batteries and portable power packs, flexible conductive films for touch and other device functions, solutions for network infrastructure, improved sensors and electromagnetic components.
The Mobile World Congress is the biggest event on the communications industry’s calendar (over 94,000 people visited the show in 2015) and provides a huge opportunity for the graphene community to pitch its breakthrough materials to key customers in the supply chain. At the event, materials providers and leading researchers will be on-hand to discuss how graphene and its derivatives can be integrated into next generation devices and update attendees on the latest scientific results.
Presenters at the Graphene Pavilion include Aixtron, Avanzare, AMO, FlexEnable, GNext, Graphenea, Libre SRL, nVision and Zap&Go, the University of Cambridge, Chalmers University of Technology, the University of Manchester, ICFO – The Institute of Photonic Sciences, Catalan Institute of Nanoscience and Nanotechnology (ICN2), CNR National Research Council and the Italian Institute of Technology.
Lab to market
Recognising that the mobile industry has much to gain from transformative materials, the congress organizers have invited Nobel Laureate Konstantin Novoselov to give a keynote presentation at this year’s event, and scheduled a panel discussion to highlight major opportunities on the horizon.
What are the price points that graphene and its derivatives need to hit to access market opportunities in composites, lubricants, 3D printing, concrete and other target applications? Who are the leading global suppliers and what are the sweet spots for the various grades of the material, which range from few-layer sheets to much larger stacks of graphene nanoplatelets?
Fullerex, an advanced materials and technology brokerage, which works with nanomaterial producers and end-users to support applications development and commercialisation, has set out to answer these questions and more in its annual bulk graphene pricing report, now updated for 2016.
Supply landscape: the number of companies offering bulk graphene compared with providers of thin-film material (source: Fullerex)
Bulk graphene is offered by producers as a functional filler to improve the properties of base materials. These additives can be sold into a wide range of industries, but which sectors offer the strongest prospects for suppliers?
One of the fastest moving opportunities for graphene producers is the emerging 3D-printing market. Suppliers of FDM 3D printing consumables in Europe and the US are facing competition from Chinese firms producing spools at lower cost. “Established companies need to differentiate their products to protect their margins and nanomaterials provide a way to do this,” Tom Eldridge, director at Fullerex told TMR+. “Adding graphene can make the filament conductive or high strength and expands the number of applications that 3D-printed parts can address.”
With relatively few materials to choose from, the 3D printing community has a healthy appetite for new products to print with, which plays well for graphene producers. The downside is that the volume of nanomaterials required is likely to be relatively low, so graphene suppliers will need to look to larger markets to justify investments in scaling up facilities.
Longer term, one of the biggest opportunities for bulk graphene could be in construction. “Concrete is the second most consumed material after water and represents a potentially huge market for graphene in terms of volume, but it will be much tougher for producers to demand premium prices,” Eldridge points out. “In this sector, it’s essential to get costs down so that your material is as competitive as possible and to achieve a favourable price-to-performance ratio,”
The benefits of adding graphene to concrete include improvements in compressive strength and flexural modulus, but the nanomaterial could also deliver sensor properties and assist in the detection of micro-cracks to monitor the ‘health’ of a structure.
To break into target markets large and small, graphene producers need to get a handle on which applications are going to make the most commercial sense to potential customers. There are other issues too. “Standardization is on everyone’s mind, and is being worked on,” comments Eldridge. “Over a shorter time-frame, consistency from individual suppliers is the key priority to get commercial-use graphene based products and systems onto the market.”
What can web scraping reveal about the commercialization of graphene? That’s the question Philip Shapira, Abdullah Gök and Fatemeh Salehi Yazdi have set out to answer using a mixture of computerized data mining and other analytical techniques.
The team, based at Manchester Business School, has chosen graphene as a ‘demonstrator’ to road-test its approach, which identifies patterns from publicly available information hosted on enterprise websites. The hope is that these methods can assist in providing ‘real-time intelligence’ to map the development of rapidly emerging materials and technologies.
In the pilot study, Shapira and his colleagues have focused on a set of 65 graphene-based small and medium-sized enterprises (SMEs) based in 16 different countries – 49.2% of the SMEs in the sample are located in North America, 15.4% in the UK, 18.5% in Western Europe and 16.9% in East Asia and emerging nations. The researchers acknowledge that they haven’t captured every graphene SME in every country, particularly in China, and note this under-representation should be kept in mind when comparing across the regions.
Presenting their findings in a Nesta working paper, the authors draw attention to the following –
Access to finance and the firms’ location are significant factors that are associated with graphene product introductions.
Patents and scientific publications are not statistically significant predictors of product development in their sample of graphene SMEs.
Graphene SMEs are focusing mainly on upstream and intermediate offerings in the value chain.
Relationship between different value chain positions – [equipment:11] [material:44] [intermediate:26] [final:2] – of SMEs in the study. Credit: Nesta Working Paper 15/14
According to the data, the mention of other 2D materials on a company website turned out to be a significantly negative predictor of introducing a product into the market. “In other words, focusing on graphene was more likely to be associated with a product introduction – perhaps because other 2D materials are as yet further away from being ready for the market or because focusing on multiple materials in a resource-constrained SME might diffuse or slow down commercialisation capabilities,” comment the authors in their work.
Supporting movement up the value chain
As the researchers note, currently there is an emphasis in SMEs on producing advanced graphene materials, although many are signalling plans to develop more intermediate graphene products that should have higher value in the marketplace. Technology intermediary organisations are likely to be important in supporting these next stages of graphene development – examples include the UK National Graphene Institute, which opened in March this year, and its sister facility the Graphene Engineering Innovation Centre, which is planned for completion in 2017.
Angstron Materials, a US supplier of single and few-layer graphene materials, announced this week that it has secured $5 million in capital to increase manufacturing capacity and bring key technologies such as its thermal management products to market. Heat spreaders developed by the firm can reduce hot-spots in mobile phones and other handheld devices, and the funding news follows reports earlier this year that Angstron’s graphene sheets have been qualified for use by a major mobile electronics company.
Thermal interface material: Angstron Materials supplies graphene-based sheets in thicknesses ranging from 5 µm to 40 µm with thermal conductivity between 800 W/m.K and 1700 W/m.K for use in electronic products such as tablets, laptops and flat screen TVs. The foils can also be used for EMI shielding.
Estimates by market analyst IDTechEx suggest that 55% of electronic failures are caused by over-heating, and enhanced thermal interface materials have a major role to play in helping devices to stay cool, perform better and last longer as developers boost their offerings by packing more processing power into increasingly compact form-factors.
“We use the planar alignment of carbon atoms to make a lightweight, flexible thermal foil with up to 1700 W/m.K in-plane thermal conductivity – substantially higher thermal conductivity than copper and offering weight savings for thermal management,” Claire Rutiser, a member of Angstron’s executive team, told TMR+. “Also, we can load thermally conductive nano graphene platelets (NGP) into a matrix – which could be thermoset, thermoplastic or non-curing (for thermal paste).”
Graphene isn’t the only option for device makers and competing thermal management materials include formulations based on silver flakes or silver nano-wires, but there are economic considerations that may favour the use of NGPs. “Silver is subject to significant price fluctuation and future price uncertainty,” Rutiser comments. “Angstron Materials has known input materials pricing and is able to enter into long term supply agreements with end users.”
Graphene has been linked with various big names in portable electronics. In 2011, Apple noted that the use of graphene thermal dissipators goes beyond cooling. Related applications include transferring heat from onboard electronics to the battery to improve runtime, which can be compromised at low temperatures.
Rutiser says that Angstron is ready with scalable production capacity and emphasised that the firm is targeting other sectors in addition to thermal management materials. She’s optimistic that over a 10 year period energy storage will grow to become one of the company’s biggest sources of revenue. Driving this are developments in graphene-wrapped silicon anodes by sister company Nanotek Instruments, which allow fabrication of Li-ion batteries with over 400 Wh/kg, and also materials for supercapacitors.
“Affordable, high-capacity energy storage is critical for the transition to electric vehicles and for grid-stabilization as the percentage of energy derived from renewables increases in the coming decades,” Rutiser explained. “These products have comparatively long qualification times due to reliability testing and industry safety standards.”
Currently, Angstron’s graphene-enhanced products and technologies are linked to five distinct portfolios – thermal management materials, energy storage systems, nanocomposites, transparent conductive films, paints and coatings. “Graphene platelets are inert to most chemical species and offer opportunities to improve barrier coatings against corrosion, chemical attack, or oxygen permeation, “ added Rutiser.
The UK welcomed an influx of graphene experts last week as Manchester University’s 200+ researchers working in the field of 2D materials were joined by hundreds more for Graphene Week 2015. The event, now in its 10th year, has grown from a small European workshop into a five-day conference boasting over 600 attendees and pushing the University Place venue to capacity. The scope of the programme has expanded too; hexagonal boron nitride (hBN), molybdenum disulphide (MoS2) and other related 2D materials have joined graphene on the ‘menu’ of structures being explored by developers. Most recently, the conference has been co-ordinated by the Graphene Flagship – a European drive to capitalize on the many opportunities for 2D materials, which launched in October 2013 and has adopted Graphene Week as its annual conference.
Plenary update: Nobel Prize winner Kostya Novoselov briefed the Graphene Week 2015 audience on major developments in the field of 2D materials.
The European Commission (EC) has given graphene and related 2D materials research a huge boost through its Flagship initiative, but as Thomas Skordas, head of the EC’s FET Flagships Unit, reminded the audience during the conference opening – the funding is not a blank cheque for 10 years. The objective is to deliver economic benefits. So far, Graphene Flagship projects have generated 3x more publications compared with the Horizon 2020 average, but to achieve its long term goal the programme needs to capitalize on this research growth.
Connecting with industry
The challenge of taking graphene and related 2D materials from the lab to the market is a focus issue for TMR+ and its sister journal Translational Materials Research (TMR), and we were delighted to be invited to the Flagship’s latest Graphene Connect workshop, co-located with Graphene Week 2015, to join in the discussion.
New facility: the Graphene Connect networking event focusing on investment opportunities was held at the UK’s National Graphene Institute in Manchester.
The Manchester session was focused on investment opportunities in graphene and related 2D materials, and put the spotlight on start-ups and early-stage companies. Fittingly, the workshop took place at the recently opened National Graphene Institute (NGI) – a facility where academia and industry are co-located to promote translation of 2D materials from the lab to the market.
Presenters from the VC community included Achim Hoffman of IP Group. He picked up on the issue of media hype surrounding graphene, which has distorted expectations. One of the key messages from the session was the need to stay focused on the fundamentals such as the market, the technology and the infrastructure. “You’ve got to go back to basics,” summed up MTI’s Mark Rahn, who also spoke at the event.
Rahn presented a snapshot of companies operating in the graphene sector. Today, materials suppliers are putting resource into stepping up the value chain by offering functionalized products and formulations that are easier for customers to evaluate and integrate. “The real hard work is how you get from a good idea to a viable production process,” said Nigel Salter, Managing Director of 2DTech – a start-up supplying graphene nanoplatelets (GNPs).
Other industrial players at the workshop included BGT Materials, a 2D materials venture with a base in the UK and a sister operation in Taiwan. According to its UK manager – Liam Britnell – BGT has developed an environmentally-friendly way to process graphene-oxide (GO). Applications include barrier films for food packaging, which exploits the material’s very low oxygen transmission characteristics.
Hexagonal highlights: the National Graphene Institute’s carbon-black coloured cladding is patterned with graphene-shaped perforations.
Whether it’s packaging or microelectronics, materials firms need to understand their potential markets and make sure that their products and processes are compatible with their target industries. To accelerate this process, Applied Nanolayers (ANL) – which grew out of Leiden University – decided to break the cord from academia early on and moved south to base itself in the heart of the Netherlands’ chip-making ecosystem. The company provides wafer-grown 2D material such as graphene or hBN for a range of device applications.
The final panel discussion of the day, which featured Graphenea, Haydale and Flexenable, highlighted the many different routes for growing and repositioning businesses in the advanced materials sector – topics that TMR will be exploring in more detail through its journal section ‘Policy, funding and business strategy’.
Graphenea began as a supplier of 2D materials for the research community, but the firm’s products also appeal to industry and in 2013 it won investment from Repsol – a multinational with activities upstream and downstream in the oil & gas sector. Most recently, Graphenea has been awarded Euro 2.5 million through the Horizon 2020 SME instrument – a phased programme of support to small-to-medium enterprises – which will allow the San Sebastian headquartered company to further scale-up its production capacity. The firm has a satellite office based in Boston, US, to strengthen its links with MIT and Harvard.
FlexEnable was spun out of Plastic Logic to give the business more freedom to apply its expertise in printing transistors on plastic beyond the display sector. Its activities include consulting services to materials companies.
Meanwhile, back at Graphene Week
There was plenty of industry input at the main conference too with updates from Bosch, IBM and Alcatel Lucent, to name just a few of the big names eyeing up opportunities for 2D materials. TMR+ spoke with IBM’s Shu-Jen Han last year, and the message remains the same in 2015 – RF devices rather than digital logic are a stronger proposition for graphene. Telecomms could be a promising area for the material thanks to graphene’s consistent performance across a wide temperature range, and useful optical properties.
Smart space: The National Graphene Institute features a ‘high-rise wildflower meadow’ designed to improve roof function by providing a green space for people and pollinators such as bees, butterflies and hoverflies. For a video tour of the building, including the lab space, check out the YouTube clip from TMR+’s sister site physicsworld.com.
Alcatel Lucent has been working with partner AMO Aachen to investigate the potential of 2D materials in enabling highly-integrated photonic subsystems. The team has come up with a photodetector featuring CVD-grown graphene on a Si waveguide, which operates in the c-band (wavelength = 1550 nm) to support data rates up to 50 GBit/s.
The next Graphene Connect workshop is scheduled for early 2016 and will explore the topic of biosensors and implants. Graphene Week 2016 will take place in Poland next June.
IDTechEx’s multi-track conference and exhibition explores the interconnected landscape of printed electronics, wearable technology, energy harvesting, the internet of things (IoT), graphene and 2D materials, 3D printing, and electric vehicles. Collaboration is key to succeeding in materials translation, and for me this was one of the big messages of the 2015 show, which brings together formulation specialists, systems developers, fabrication experts, measurement providers, and customer groups, all under the same roof for two days (or more if you sign-up to masterclasses).
Dialogue between technology providers and end-users helps to resolve uncertainty in emerging fields such as printed and flexible electronics where – i) customers can be unsure about what’s possible and ii) suppliers need guidance on market requirements.
Bringing new technology to market
On day one, speakers from Qualcomm and Flextronics outlined how their firms bring new technology to the market. In Qualcomm’s case, its approach is built on four pillars – i) system R&D leadership, ii) design for manufacturability, iii) supply chain management and iv) customer support and engineering. It’s important not to overlook the final step. “The value proposition is only realized if you can propagate this to the customer,” Stein Lundby (R&D manager at Qualcomm) reiterated to audience.
Qualcomm, which Lundby describes as a ‘surface electronics’ company, is exploring opportunities for a hybrid product combining traditional crystalline based electronics with printed electronic components. Developed with Enfucell – a provider of printed power sources – the device features a 3-axis gyroscope and 3-axis accelerometer together with integrated battery and system electronics packaged in a band-aid style form factor. Users can stick the sensor on items such as golf clubs to determine how new products might improve their game, but this is just one possible scenario.
To navigate markets such as wearables, Flextronics – which focuses on production equipment and know-how – has opened design centres to help customers with product development and new use-cases such as electronic displays for athletic clothing. In his presentation, Keith Churches (head of innovation services at Flextronics) showed how the company brings new ideas to the market by configuring product-specific development networks that link the firm’s expertise with partners such as OEMs, universities and research institutes.
Nanomaterials Directa Plus – which was founded in 2005 and opened its graphene factory in 2014 – used the graphene and 2D materials conference track to talk through its collaboration with Vittoria Industries and highlight early market opportunities for graphene. Dubbed the wonder material, graphene – an ultra-thin layer of carbon – has been shown to have record-breaking electrical, thermal and mechanical properties, but breakthrough results in the lab don’t guarantee commercial success. “You have to be brave to be in the graphene market,” Giulio Cesareo (CEO of Directa Plus) commented.
Full house: interest in graphene and related 2D materials remains strong.
Vittoria uses Directa Plus’ graphene nanoplatelets to formulate bicycle tyres and wheels with enhanced properties such as heat dissipation and lateral stiffness. There are 165 wheel makers in the world, Rudi Campagne (founder of Vittoria Industries) told the audience, and the use of nanomaterials such as graphene is an effective way for Vittoria to differentiate itself from the competition.
Early uses of graphene provide a platform for growth in other sectors by establishing a materials supply chain. Beyond tyres and wheels, Directa Plus is looking at opportunities for graphene in cleaning up contaminated soil and water. In his talk, Cesareo explained that linked graphene platelets have the potential to remove hydrocarbon pollution from lakes, according to test results. Literature from the firm claims that 1 gram of its Graphene Plus sorbent can adsorb up to 80-90 grams of oil – for more details, visit the GEnIuS project website, a programme co-founded by European Union within the Eco-Innovation initiative.
Exhibition: new products launched at the show included Ceradrop’s ‘F-Serie’ multi-material printer.
The discussion then moved on to opportunities for 2D materials in the electronics industry. If graphene does make an impact in this sector it is likely to be driven by novel applications, based on the views of the speakers in the opening session. “Graphene will not replace silicon in standard devices,” commented Guenther Ruhl (lead principal in new materials at Infineon Technologies) during his talk.
Touch screens are also looking unlikely as a big opportunity for graphene. “Graphene transparent conductive films are among the worst performers in a crowded market,” explained Khasha Ghaffarzadeh (head of consulting at IDTechEx). Like Ruhl, he feels that 2D materials could have more impact in new product categories. “The beauty of graphene is that there are many target industries and applications,” Ghaffarzadeh added.
OPV and R2R technology
Analyst events such as the IDTechEx show give attendees a view on tomorrow’s technology today. Two further highlights for me from the keynote presentations were Heliatek’s building integrated photovoltaics (BIPV) and Asahi Kasei’s e-beam fabricated seamless roller for printing transistors.
Show venue: Estrel, Berlin
In the afternoon on day one, Martin Pfeiffer (chief technology officer at Heliatek) outlined what he feels is a sweet spot for OPV – active facades. To compete with silicon, OPV has to bring something different, which it can when applications demand flexible and lightweight solutions. He added that the energy payback for an OPV cell can be as little as 3 months, as determined by the EU project dubbed X10D. Pfeiffer revealed that large-scale trials of the firm’s material were now underway in China and Germany on concrete (in Shanghai), PVC membrane (in Berlin) and glass (in Dresden) structures, with another pilot project due to start soon in Singapore on a glass and steel construction.
There were more glimpses of the future on day two when Masayuki Abe of Japanese giant Asahi Kasei – which operates in chemicals, electronics and healthcare sectors – presented his team’s work on seamless roller mold (SRM) technology for roll-to-roll (R2R) printing of sub-micron feature sizes. To make the mold, they rotated a super-smooth (2 nm roughness) roller under an e-beam writer. Moving the roller laterally (as well as rotating it) allows the team to create complex mold patterns. To test the process, Abe’s group used one of its roller molds to print a 200 ppi, 125 micron pitch TFT array. Abe was clearly proud of his team’s results and sees a bright future for the technique. “SRM will bring about the realization of high-resolution printing,” he told the audience.
Europe’s Graphene Flagship has released details of its 6th Graphene Connect workshop, which aims to introduce business angels to graphene and create an arena for small to medium enterprises (SMEs) and venture capital (VC) firms to interact.
‘The purpose of the flagship is not to perform research — it’s to bring research into society,’ Helena Theander, a senior member of the Graphene Flagship’s innovation team, told Translational Materials Research (TMR) in a recent article highlighting the need to engage SMEs in materials commercialization. ‘Graphene Connect is a process to get more industry players interested in graphene and related 2D materials.’
This latest installment in the Graphene Connect series coincides with Graphene Week 2015 and will take place in Manchester, UK, on Monday 22 June.
The workshop programme includes –
Presentations by firms operating in the graphene sector.
VC talks on investing in graphene given by industry representatives, followed by a panel discussion.
Matchmaking activities for SMEs and entrepreneurs to meet and interact with the venture capital community and explore business opportunities.
Europe’s Graphene Flagship – a € 1 billion research initiative tasked with bringing together academia and industry to translate 2D materials from the lab to the market – has released an Open Access version of its science and technology roadmap highlighting key application areas for graphene and related structures and providing estimates of timelines to market.
The report (PDF | Rich HTML) includes the views of more than 60 academics and industrial partners, and concludes a four-year project to collect and coordinate information “to guide the community
towards the development of products based on graphene, related two dimensional (2d) crystals and hybrid systems.”
The roadmap flags flexible electronics, composites, and energy as three areas that could generate close-to-market products within a 10-year timeline. Further out, the programme hopes to see silicon-integrated photonic devices, sensors, high-speed electronics, and biomedical devices based on 2D materials also making an impact beyond the lab.
Supercapacitors are a promising application for advanced materials such as high surface area nanocarbons, but what are the translational issues and market factors that researchers need to consider to win-over commercial partners? To find out more on the topic, TMR+ spoke with Franco Gonzalez, a senior analyst at IDTechEx and co-author of ‘Electrochemical Double Layer Capacitors: Supercapacitors 2014-2024’ – a 10 year forecast analysing the market, applications, technology, patent and profit trends, and key players in the sector.
Advantages over batteries
Supercapacitors don’t rely on chemical reactions and this gives them several advantages over batteries including a higher power capacity per unit mass, superior operation at low temperatures and extended operational lifetime. Truck-makers are using supercapacitors to guarantee that vehicles will start in very cold weather – a scenario where lead-acid batteries perform poorly as their energy capacity can be reduced by as much as 50%.
The longer cycle lifetimes of supercapacitors compared with batteries can lower system maintenance costs and improve reliability. It makes devices attractive for large resource power applications, particular in remote locations. In wind farms, supercapacitors are used to power actuators that change the blade pitch in high winds to protect the turbines.
IDTechEx senior analyst, Franco Gonzalez
Although supercapacitors store less energy than batteries, they can be charged very quickly without detriment (unlike batteries). This makes them ideal for regenerative breaking systems, for example on trains and trams, which convert kinetic energy into electricity. They can also be configured to recover potential energy stored in cranes operating at cargo loading and unloading sites. “At ports, these machines can be in use almost constantly, so it’s a great opportunity for energy recovery,” said Gonzalez. “The need to reduce CO2 emissions is driving the market.”
It often makes sense to pair a supercapacitor and a battery together. “Power surges reduce the energy capacity of a battery,” he explained. “But you can protect it using a supercapacitor.” The combination can be used to extend the lifetime of batteries in renewable energy systems, or in smart phones where power-demand fluctuates depending on the functions in use.
As a general rule, supercapacitors are well-suited to applications with highly-variable power demands. In principle, this means they are a great match for ‘stop-start’ systems fitted to modern cars, which switch-off the engine while you are waiting in traffic or at stop lights and then restart the vehicle when you engage the gearbox. Unfortunately, it’s not that simple.
“Different industries focus on different parameters,” Gonzalez cautioned. “Auto-makers are looking for supercapacitors that are half the price of current devices as they focus on the cost per unit energy and are concerned about the selling price of the car.”
Sales of electric buses and on the other hand are much less sensitive to the initial purchase price as buyers in this sector pay more attention to the total cost of ownership of the vehicle. In this case, because supercapacitors bring down the price per charging cycle, the market is more lucrative for developers.
Today, supercapacitors are more attractive to industrial users that are open to considering the system level cost rather than the cost per unit energy of devices. But, as Gonzalez points out, supercapacitor manufacturers are nevertheless working hard at the material level to reduce price and improve device performance to offer a better cost per unit energy to customers.
Advances in materials can contribute in a number of ways to making supercapacitors more competitive in the market. Increasing the surface area of the electrodes through activated carbons and nanomaterials will drive up the capacitance and benefit the energy storage capacity of the device. At the same time, finding ways to reduce the resistance (of the active material, the electrolyte, and the porous separator) will boost the power output.
However, it is the operation of supercapacitor cells at higher voltages (V) and finding the right materials to make this happen, which may impact performance in the short to medium term. Both the power and the energy of a capacitor are proportional to V2. “Electrolytes in organic solvents can withstand 2.7 V, but developers are also looking at ionic liquids – room temperature salts – that operate at 5V,” said Gonzalez.
Devices come in many shapes and sizes, and he highlights micro-supercapacitors as a particularly exciting and growing area of research. Gonzalez advises researchers to look at lower-cost materials and manufacturing methods in the first instance. “If you want to use expensive materials then you need to find an application that will pay for that,” he commented. “Researchers need to be aware of how the industry is changing and the relative sensitivity to price of the different applications.”