17 Jun 2017
Tesla is revolutionizing batteries for electric bicycles and it has to do with the recent changes at the leading battery cell makers BMZ, Panasonic, Sony, Samsung and LG. Together these five make out some 80% of the world production of battery cells.
These five cell makers used to supply huge numbers of cylindrical shaped cells to the IT industry until the industry changed completely from using cylindrical shaped cells to flat shaped batteries which are now used in laptops, tablets and smartphones. Tesla placing huge orders for cylindrical shaped cells pushed battery cell makers to new highs.
Europe’s largest battery maker BMZ boss introduced the 21700 cell that will revolutionize electric bicycles. In particular as the 21700 cell not only offers a much prolonged lifetime but also batteries with a much bigger capacity for more power and pedal-supported mileage.
The extraordinary features that the 21700 battery cell brings to e-bikes will be the new standard in e-bike batteries. And that this new standard will already be available in 2018.
Instead of the current 18650 (18mm diameter and 65mm high) cell size the 21700 cell is 21mm diameter and 70mm high. The bigger size is bringing a bigger output; up to 4.8Ah. With that capacity the battery lifetime is extended from the current some 500 charging cycles up to 1,500 to 2,000 cycles.
BMZ, together with another global battery player, managed to develop batteries that offer a much longer lifespan thanks to the fact that the new batteries create less heat and has up to 60% more capacity.
17 Jun 2017
Could a new material involving a carbon nanotube and graphene hybrid put an end to the dendrite problem in lithium batteries?
The high energy capacity of lithium-ion batteries has led to them powering everything from tiny mobile devices to huge trucks. But current lithium-ion battery technology is nearing its limits and the search is on for a better lithium battery. But one thing stands in the way: dendrites. If a new technology by Rice University scientists lives up to its potential, it could solve this problem and enable lithium-metal batteries that can hold three times the energy of lithium-ion ones.
Dendrites are microscopic lithium fibers that form on the anodes during the charging process, spreading like a rash till they reach the other electrode and causing the battery to short circuit. As companies such as Samsung know only too well, this can cause the battery to catch fire or even explode.
“Lithium-ion batteries have changed the world, no doubt,” says chemist Dr. James Tour, who led the study. “But they’re about as good as they’re going to get. Your cellphone’s battery won’t last any longer until new technology comes along.”
So until scientists can figure out a way to solve the problem of dendrites, we’ll have to put our hopes for a higher capacity, faster-charging battery that can quell range anxiety on hold. This explains why there’s been no shortage of attempts to solve this problem, from using Kevlar to slow down dendrite growth to creating a new electrolyte that could lead to the development of an anode-free cell. So how does this new technology from Rice University compare?
For a start, it’s able to stop dendrite growth in its tracks. Key to it is a unique anode made from a material that was first created at the university five years ago. By using a covalent bond structure, it combines a two-dimensional graphene sheet and carbon nanotubes to form a seamless three-dimensional structure. As Tour explained back when the material was first unveiled:
“By growing graphene on metal (in this case copper) and then growing nanotubes from the graphene, the electrical contact between the nanotubes and the metal electrode is ohmic. That means electrons see no difference, because it’s all one seamless material.”
Close-up of the lithium metal coating the graphene-nanotube anode (Credit: Tour Group/Rice University)
Envisioned for use in energy storage and electronics applications such as supercapacitors, it wasn’t until 2014, when co-lead author Abdul-Rahman Raji was experimenting with lithium metal and the graphene-nanotube hybrid, that the researchers discovered its potential as a dendrite inhibitor.
“I reasoned that lithium metal must have plated on the electrode while analyzing results of experiments carried out to store lithium ions in the anode material combined with a lithium cobalt oxide cathode in a full cell,” says Raji. “We were excited because the voltage profile of the full cell was very flat. At that moment, we knew we had found something special.”
Closer analysis revealed no dendrites had grown when the lithium metal was deposited into a standalone hybrid anode – but would it work in a proper battery?
To test the anode, the researchers built full battery prototypes with sulfur-based cathodes that retained 80 percent capacity after more than 500 charge-discharge cycles (i.e. the rough equivalent of what a cellphone goes through in a two-year period). No signs of dendrites were observed on the anodes.
How it works
The low density and high surface area of the nanotube forest allow the lithium metal to coat the carbon hybrid material evenly when the battery is charged. And since there is plenty of space for the particles to slip in and out during the charge and discharge cycle, they end up being evenly distributed and this stops the growth of dendrites altogether.
According to the study, the anode material is capable of a lithium storage capacity of 3,351 milliamp hours per gram, which is close to pure lithium’s theoretical maximum of 3,860 milliamp hours per gram, and 10 times that of lithium-ion batteries. And since the nanotube carpet has a low density, this means it’s able to coat all the way down to substrate and maximize use of the available volume.
“Many people doing battery research only make the anode, because to do the whole package is much harder,” says Tour. “We had to develop a commensurate cathode technology based upon sulfur to accommodate these ultrahigh-capacity lithium anodes in first-generation systems. We’re producing these full batteries, cathode plus anode, on a pilot scale, and they’re being tested.”
The study was published in ACS Nano.
Source: Rice University
17 Jun 2017
Electrodes are critical parts of every battery architecture — charge too fast, and you can decrease the charge-discharge cycle life or damage the battery so it won’t charge anymore. Scientists have built a new design and chemistry for electrodes. Their design involves advanced, nanostructured electrodes containing molybdenum disulfide and carbon nanofibers (Advanced Energy Materials, “Pseudocapacitive charge storage in thick composite MoS2 nanocrystal-based electrodes”). These composite materials have internal atomic-scale pathways. These paths are for both fast ion and electron transport, allowing for fast charging.
|Battery electrodes made of a molybdenum disulfide nanocrystal composite have internal pathways to allow lithium ions to move quickly through the electrode, speeding up the rate that the battery can charge. The key features in the structure that enable the flow of the lithium ions are the small, 20-40 nanometer, diameter of the nanocrystals (in contrast, human hairs are about 100,000 nanometers in diameter) coupled with the porosity and planar lamellar pathways shown in the electron micrograph. (Image: Sarah Tolbert, University of California, Los Angeles)|
|The new battery electrodes provide several benefits. The electrodes allow fast charging. They also have stable charge/discharge behavior, so the batteries last longer. These electrodes show promise for practical electrical energy storage systems.|
|New battery electrodes based on nanostructured molybdenum disulfide combine the ability to charge in seconds with high capacity and long cycle life. Typical lithium-ion batteries charge slowly due to slow diffusion of lithium ions within the solid electrode.|
|Another type of energy storage device (a.k.a., pseudocapacitors), which has similarities to the capacitors found in common electrical circuits, speeds up the charging process by using reactions at or near the electrode surface, thus avoiding slow solid-state diffusion pathways.|
|Nanostructured electrodes allow the creation of large surface areas so that the battery can work more like a pseudocapacitor. In this work at the University of California, Los Angeles, scientists made nanostructured electrodes from a molybdenum disulfide-carbon composite.|
|Many electrodes are based on metal oxides, but because sulfur more weakly interacts with lithium than oxygen, lithium atoms can move more freely in the metal sulfide than the metal oxide. The result is a battery electrode that shows high capacity and very fast charging times.|
|The novel electrodes deliver specific capacities of 90 mAh/g (about half that of a typical lithium-ion battery cathode) charging in less than 20 seconds, and retain over 80 percent of their original capacity after 3,000 charge/discharge cycles. Capacities of greater than 180 mAh/g (similar to cathodes in conventional lithium-ion cells) are achieved at slower charging rates.|
|The results have exciting implications for the development of fast-charging energy storage systems that could replace traditional lithium-ion batteries.|
|Source: U.S. Department of Energy, Office of Science|
18 May 2017
Battery stores energy in nontoxic, noncorrosive aqueous solutions
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new flow battery that stores energy in organic molecules dissolved in neutral pH water.
This new chemistry allows for a non-toxic, non-corrosive battery with an exceptionally long lifetime and offers the potential to significantly decrease the costs of production.
The research, published in ACS Energy Letters, was led by Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies and Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science.
Flow batteries store energy in liquid solutions in external tanks — the bigger the tanks, the more energy they store.
18 May 2017
Electrodes containing porous graphene and a niobia composite could help improve electrochemical energy storage in batteries. This is the new finding from researchers at the University of California at Los Angeles who say that the nanopores in the carbon material facilitate charge transport in a battery.
By fine tuning the size of these pores, they can not only optimize this charge transport but also increase the amount of active material in the device, which is an important step forward towards practical applications.
Batteries and supercapacitors are two complementary electrochemical energy-storage technologies. They typically contain positive and negative electrodes with the active electrode materials coated on a metal current collector (normally copper or aluminium foil), a separator between the two electrodes, and an electrolyte that facilitates ion transport.
The electrode materials actively participate in charge (energy) storage, whereas the other components are passive but nevertheless compulsory for making the device work.
Batteries offer high energy density but low power density while supercapacitors provide high power density with low energy density.
Although lithium-ion batteries are the most widely employed batteries today for powering consumer electronics, there is a growing demand for more rapid energy storage (high power) and higher energy density. Researchers are thus looking to create materials that combine the high-energy density of battery materials with the short charging times and long cycle life of supercapacitors.
Such materials need to store a large number of charges (such as Li ions) and have an electrode architecture that can quickly deliver charges (electrons and ions) during a given charge/discharge cycle.
26 Mar 2017
A battery that can be charged in seconds, has a large capacity and lasts ten to twelve years? Certainly, many have wanted such a thing. Now the FastStorageBW II project – which includes Fraunhofer – is working on making it a reality. Fraunhofer researchers are using pre-production to optimize large-scale production and ensure it follows the principles of Industrie 4.0 from the outset.
Imagine you’ve had a hectic day and then, to cap it all, you find that the battery of your electric vehicle is virtually empty. This means you’ll have to take a long break while it charges fully. It’s a completely different story with capacitors, which charge in seconds. However, they have a different drawback: they store very little energy.
In the FastStorageBW II project, funded by the Baden-Württemberg Ministry of Economic Affairs, researchers from the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, together with colleagues from the battery manufacturer VARTA AG and other partners, are developing a powerful hybrid storage system that combines the advantages of lithium-ion batteries and supercapacitors.
“The PowerCaps have a specific capacity as high as lead batteries, a long life of ten to twelve years, and charge in a matter of seconds like a supercapacitor,” explains Joachim Montnacher, Head of the Energy business unit at Fraunhofer IPA. What’s more, PowerCaps can operate at temperatures of up to 85 degree Celsius. They withstand a hundred times more charge cycles than conventional battery systems and retain their charge over several weeks without any significant losses due to self-discharge.
“Supercapacitors may be providing an alternative to electric-car batteries sooner than expected, according to a new research study. Currently, supercapacitors can charge and discharge rapidly over very large numbers of cycles, but their poor energy density per kilogram —- at just one twentieth of existing battery technology — means that they can’t compete with batteries in most applications. That’s about to change, say researchers from the University of Surrey and University of Bristol in conjunction with Augmented Optics.
Large-scale production with minimum risk
The Fraunhofer IPA researchers’ main concern is with manufacturing: to set up new battery production, it is essential to implement the relevant process knowledge in the best possible way.
After all, it costs millions of euros to build a complete manufacturing unit. “We make it possible for battery manufacturers to install an intermediate step – a small-scale production of sorts – between laboratory production and large-scale production,” says Montnacher. “This way, we can create ideal conditions for large-scale production, optimize processes and ensure production follows the principles of Industrie 4.0 from the outset. Because in the end, that will give companies a competitive advantage.” Another benefit is that this cuts the time it takes to ramp up production by more than 50 percent.
For this innovative small-scale production setup, researchers cleverly combine certain production sequences. However, not all systems are connected to each other – at least, as far as the hardware is concerned. More often, it is an employee that carries the batches from one machine to the next. Ultimately, it is about developing a comprehensive understanding of the process, not about producing the greatest number of products in the shortest amount of time. For example, this means clarifying questions such as if the desired quality can be reproduced. The systems are designed as flexibly as possible so that they can be used for different production variations.
Making large-scale production compatible with Industrie 4.0
As far as software is concerned, the systems are thoroughly connected. Like process clusters, they are also equipped with numerous sensors, which show the clusters what data to capture for each of the process steps. They communicate with one another and store the results in a cloud. Researchers and entrepreneurs can then use this data to quickly analyze which factors influence the quality of the product – Does it have Industrie 4.0 capability? Were the right sensors selected? Do they deliver the desired data? Where are adjustments required?
Fraunhofer IPA is also applying its expertise beyond the area of production technology: The scientists are developing business models for the marketing of battery cells, they are analyzing resource availability, and they are optimizing the subsequent recycling of PowerCaps.
Explore further: Virtual twin controls production
A new company Tenka Energy, LLC ™ has been formed to exploit and commercialize the Next Generation Super-Capacitors and Batteries. The opportunity is based on Nanoporous-Nickel Flexible Thin-Form, Scalable Super Capacitors and Si-Nanowire Battery Technologies with Exclusive IP Licensing Rights from Rice University.
… Problem 1: Current capacitors and batteries being supplied to the relevant markets lack the sustainable power density, discharge and recharge cycle and warranty life. Combined with a weight/ size challenge and the lack of a ‘flexible form factor’, existing solutions lack the ability to scale and manufacture at Low Cost, to satisfy the identified industries’ need for solutions that provide commercial viability & performance.
Solution: For Marine & Drone Batteries – Medical Devices
- High Energy Density = 2X More Time on the Water; 2X Flight Time for Drones
- Simplified Manufacturing = Lower Costs
- Simple Electrode Architecture = Flex Form Factor (10X Energy Density Factor)
- Flexible Form = Dramatically Less Weight and Better Weight Distribution
- Easy to Scale Technology
To Read the Full Article Click on the Link Below:
28 Feb 2017
Technology I: University of Central Florida
Leaving your phone plugged in for hours could become a thing of the past, thanks to a new type of battery technology that charges in seconds and lasts for over a week.
Watch the Video
While it probably won’t be commercially available for a years, the researchers said it has the potential to be used in phones, wearables and electric vehicles.
“If they were to replace the batteries with these supercapacitors, you could charge your mobile phone in a few seconds and you wouldn’t need to charge it again for over a week,” said Nitin Choudhary, a UCF postdoctoral associate, who conducted much of the research, published in the academic journal ACS Nano.
How does it work?
Unlike conventional batteries, supercapacitors store electricity statically on their surface which means they can charge and deliver energy rapidly. But supercapacitors have a major shortcoming: they need large surface areas in order to hold lots of energy.
To overcome the problem, the researchers developed supercapacitors built with millions of nano-wires and shells made from two-dimensional materials only a few atoms thick, which allows for super-fast charging. Their prototype is only about the size of a fingernail.
“For small electronic devices, our materials are surpassing the conventional ones worldwide in terms of energy density, power density and cyclic stability,” Choudhary said.
Cyclic stability refers to how many times a battery can be charged, drained and recharged before it starts to degrade. For lithium-ion batteries, this is typically fewer than 1,500 times.
Supercapacitors with two-dimensional materials can be recharged a few thousand times. But the researchers say their prototype still works like new even after being recharged 30,000 times.
Those that use the new materials could be used in phones, tablets and other electronic devices, as well as electric vehicles. And because they’re flexible, it could mean a significant development for wearables.
Technology II: Rice University
Identified Key Markets and Commercial Applications
- Medical Devices and Wearable Electronics
- Drone/Marine Batteries and Power Banks
- Powered Smart Cards and Motor Cycle/ EV Batteries
- Sensors & Power Units for the iOT (Internet of Things) [Flexible Form, Energy Dense]
The Coming Power Needs of the iOT
- The IoT is populated with billions of tiny devices.
- They’re smart.
- They’re cheap.
- They’re mobile.
- They need to communicate.
- Their numbers growing at 20%-30%/Year.
The iOT is Hungry for POWER! All this demands supercapacitors that can pack a lot of affordable power in very small volumes …Ten times more than today’s best supercapacitors can provide.
Highly Scalable – Energy Dense – Flexible Form – Rapid Charge
Problem 1: Current capacitors and batteries being supplied to the relevant markets lack the sustainable power density, discharge and recharge cycle, warranty life combined with a ‘flexible form factor’ to scale and satisfy the identified industry need for commercial viability & performance.
Solution I: (Minimal Value Product) Tenka is currently providing full, functional Super Capacitor prototypes to an initial customer in the Digital Powered Smart Card industry and has received two (2) phased Contingent Purchase Orders during the First Year Operating Cycle for 120,000 Units and 1,200,000 Units respectively.
Solution II: For Drone/ Marine Batteries – Power Banks & Medical Devices
- Double the current ‘Time Aloft’ (1 hour+)
- Reduces operating costs
- Marine batteries – Less weight, longer life, flex form
- Provides Fast Recharging, Extended Life Warranty.
- Full -battery prototypes being developed
Small batteries will be produced first for Powered Digital Smart Cards (In addition to the MVP Super Caps) solving packaging before scaling up drone battery operations. Technical risks are mainly associated with packaging and scaling.
The Operational Plan is to take full advantage of the gained ‘know how’ (Trade Secrets and Processes) of scaling and packaging solutions developed for the Powered Digital Smart Card and the iOT, to facilitate the roll-out of these additional Application Opportunities. Leveraging gained knowledge from operations is projected to significantly increase margins and profitability. We will begin where the Economies of Scale and Entry Point make sense (cents)!
“We are building and Energy Storage Company starting Small & Growing Big!”
Watch the YouTube Video
07 Oct 2016
** Special to the Washington Post
The batteries that power our high-tech lifestyle are built using materials extracted in dirty, often life-threatening conditions.
If you have a cell phone, laptop, a hybrid car, or an electric vehicle, you may want to sit down. This may hurt.
You have probably heard of blood diamonds and conflict minerals. Maybe you’ve even read up a bit on how big consumer tech companies are trying (and, in some cases, being forced by governments) to sort out where the materials that go into their gadgets come from. But stories about “supply chains,” “globalization,” and “poor working conditions” can seem a world away, or just plain academic.
In a sweeping, heartbreaking series, the Washington Post is making sure it hits home.
Take the example of Yu Yuan, a farmer who lives near a graphite factory in northeastern China. In a video, he swipes at shimmering grime accumulated in his window sill and points at a barren cornfield.
The crops turn black with graphite dust he says, and don’t grow properly. He and his wife worry about the air they’re breathing and their water is undrinkable, polluted by chemicals dumped from the graphite plant. “There is nothing here once the factory is done damaging this place,” he says.
Workers in Lubumbashi, Democratic Republic of the Congo, tend to an oven that processes slag from the region’s cobalt and copper-rich ores.
Over two pieces so far, the Post has traced the path of first cobalt and then graphite as they make their way from mines to factories and ultimately into our hands as the cathodes and anodes, respectively, for lithium-ion batteries.
Each story is a remarkable blend of globe-spanning investigative journalism, business reporting, and an appeal to us to confront the consequences of owning the devices that power our high-tech lifestyles.
While graphite is mined and processed mostly in China, a huge amount of cobalt comes from mines in the Democratic Republic of the Congo, where “artisanal” miners sometimes dig through the floor of their own houses in search of ore. Mines collapse frequently. Injuries and death are commonplace.
Once extracted, the materials end up in Asia, where companies you’ve probably never heard of turn them into battery parts. The largest battery makers in the world, including Samsung SDI, LG Chem, and Panasonic, then purchase the components and turn them into batteries that go into phones, computers, and cars. (article continued below)
A “New Way” to Power Our World?
Read (Watch the YouTube Video Below) About a New Energy Storage Company ~ Making Energy Dense, Flexible Form, Rapid Charge/ Re-Charge Super Capacitors and Batteries for Medical Devices, Drone Batteries, Power Banks, Motorcycle and EV Batteries, developed from a Rice University Technology using ‘Nanoporous Nickle’ and ‘Si Nano Wires.
(article continued) Lithium batteries are prized for being light and having a high energy density compared to other battery chemistries. The modern smartphone would be difficult to imagine without a lithium battery as its power supply. They help power hybrid cars, and the small but fast-growing fleet of all-electric vehicles wouldn’t exist without them.
Interest in electric cars, in particular, is fueled by claims that the vehicles are clean and good for the environment. That may be true in the countries where they are mostly sold. But when we consider the bigger picture, the reality is something else altogether.
Read More: MIT Review – August 2016
Startups with novel chemistries tend to falter before they reach full production.
Earlier this year, Ellen Williams, the director of ARPA-E, the U.S. Department of Energy’s advanced research program for alternative energy, made headlines when she told the Guardiannewspaper that “We have reached some holy grails in batteries.”
Despite very promising results from the 75-odd energy-storage research projects that ARPA-E funds, however, the grail of compact, low-cost energy storage remains elusive.
A number of startups are closer to producing devices that are economical, safe, compact, and energy-dense enough to store energy at a cost of less than $100 a kilowatt-hour. Energy storage at that price would have a galvanic effect, overcoming the problem of powering a 24/7 grid with renewable energy that’s available only when the wind blows or the sun shines, and making electric vehicles lighter and less expensive.
But those batteries are not being commercialized at anywhere near the pace needed to hasten the shift from fossil fuels to renewables. Even Tesla CEO Elon Musk, hardly one to underplay the promise of new technology, has been forced to admit that, for now, the electric-car maker is engaged in a gradual slog of enhancements to its existing lithium-ion batteries, not a big leap forward.
In fact, many researchers believe energy storage will have to take an entirely new chemistry and new physical form, beyond the lithium-ion batteries that over the last decade have shoved aside competing technologies in consumer electronics, electric vehicles, and grid-scale storage systems. In May the DOE held a symposium entitled “Beyond Lithium-Ion.” The fact that it was the ninth annual edition of the event underscored the technological challenges of making that step.
Qichao Hu, the founder of SolidEnergy Systems, has developed a lithium-metal battery (which has a metallic anode, rather than the graphite material used for the anode in traditional lithium-ion batteries) that offers dramatically improved energy density over today’s devices (see“Better Lithium Batteries to Get a Test Flight”). The decade-long process of developing the new system highlighted one of the main hurdles in battery advancement: “In terms of moving from an idea to a product,” says Hu, “it’s hard for batteries, because when you improve one aspect, you compromise other aspects.”
Added to this is the fact that energy storage research has a multiplicity problem: there are so many technologies, from foam batteries to flow batteries to exotic chemistries, that no one clear winner is attracting most of the funding and research activity.
According to a recent analysis of more than $4 billion in investments in energy storage by Lux Research, startups developing “next-generation” batteries—i.e., beyond lithium-ion—averaged just $40 million in funding over eight years. Tesla’s investment in its Gigafactory, which will produce lithium-ion batteries, will total around $5 billion. That huge investment gap is hard to overcome.
“It will cost you $500 million to set up a small manufacturing line and do all the minutiae of research you need to do to make the product,” says Gerd Ceder, a professor of materials science at the University of California, Berkeley, who heads a research group investigating novel battery chemistries. Automakers, he points out, may test new battery systems for years before making a purchase decision. It’s hard to invest $500 million in manufacturing when your company has $5 million in funding a year.
Even if new battery makers manage to bring novel technologies to market, they face a dangerous period of ramping up production and finding buyers. Both Leyden Energy and A123 Systems failed after developing promising new systems, as their cash needs climbed and demand failed to meet expectations. Two other startups, Seeo and Sakti3, were acquired before they reached mass production and significant revenues, for prices below what their early-stage investors probably expected.
Meanwhile, the Big Three battery producers, Samsung, LG, and Panasonic, are less interested in new chemistries and radical departures in battery technology than they are in gradual improvements to their existing products. And innovative battery startups face one major problem they don’t like to mention: lithium-ion batteries, first developed in the late 1970s, keep getting better.
Read more: Why We Still Don’t Have Better Batteries The Washington Post
Genesis Nanotechnology, Inc.
Follow and ‘Like’ Us on Facebook: https://www.facebook.com/GenesisNanoTech/
Follow Us On Twitter: https://twitter.com/GenesisNanoTech
“Join the Conversation” on Our LinkedIn ‘Nano Network’ Group:https://www.linkedin.com/groups/3935461
Connect To Our Website: http://genesisnanotech.com/
Watch Our YouTube Video: https://youtu.be/Y1618kgUSXI
Follow Our ‘Top Ten’ Blog: “Great Things from Small Things”: https://genesisnanotech.wordpress.com/
Contact with Your Comments – We Love Hearing from You!
Drones are used for various applications such as aero picturing, disaster recovery, and delivering. Despite attracting attention as a new growth area, the biggest problem of drones is its small battery capacity and limited flight time of less than an hour. A fuel cell developed by Prof. Gyeong Man Choi (Dept. of Materials Science and Engineering) and his research team at POSTECH can solve this problem.
Prof. Choi and his Ph.D. student Kun Joong Kim have developed a miniaturized solid oxide fuel cell (SOFC) to replace lithium-ion batteries in smartphones, laptops, drones, and other small electronic devices. Their results were published in the March edition of Scientific Reports, the sister journal of Nature.
Their achievement has been highly evaluated because it can be utilized, not only for a small fuel cell, but also for a large-capacity fuel cell that can be used for a vehicle.
The SOFC, referred to as a third-generation fuel cell, has been intensively studied since it has a simple structure and no problems with corrosion or loss of the electrolyte. This fuel cell converts hydrogen into electricity by oxygen-ion migration to fuel electrode through an oxide electrolyte. Typically, silicon has been used after lithography and etching as a supporting component of small oxide fuel cells. This design, however, has shown rapid degradation or poor durability due to thermal-expansion mismatch with the electrolyte, and thus, it cannot be used in actual devices that require fast On/Off.
The research team developed, for the first time in the world, a new technology that combines porous stainless steel, which is thermally and mechanically strong and highly stable to oxidation/reduction reactions, with thin-film electrolyte and electrodes of minimal heat capacity. Performance and durability were increased simultaneously. In addition, the fuel cells are made by a combination of tape casting-lamination-cofiring (TLC) techniques that are commercially viable for large scale SOFC.
The fuel cells exhibited a high power density of ~ 560 mW cm-2 at 550 oC. The research team expects this fuel cell may be suitable for portable electronic devices such as smartphones, laptops, and drones that require high power-density and quick on/off. They also expect to develop large and inexpensive fuel cells for a power source of next-generation automotive.
With this fuel cell, drones can fly more than one hour, and the team expects to have smartphones that charge only once a week.
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology.