Posts belonging to Category electronics



Hydrogen Electric Car Powered By Fuel Cells 4 Times More Efficient

Inspired by the humble cactus, a new type of membrane has the potential to significantly boost the performance of fuel cells and transform the electric vehicle industry. The membrane, developed by scientists from CSIRO (Australia) and Hanyang University in Korea, was described today in the journal Nature . The paper shows that in hot conditions the membrane, which features a water repellent skin, can improve the efficiency of fuel cells by a factor of four.

According to CSIRO researcher and co-author Dr Aaron Thornton, the skin works in a similar way to a cactus plant, which thrives by retaining water in harsh and arid environments.

cactus

Fuel cells, like the ones used in electric vehicles, generate energy by mixing together simple gases, like hydrogen and oxygen. However, in order to maintain performance, proton exchange membrane fuel cells – or PEMFCs – need to stay constantly hydrated,” Dr Thornton said.

At the moment this is achieved by placing the cells alongside a radiator, water reservoir and a humidifier. The downside is that when used in a vehicle, these occupy a large amount of space and consume significant power,” he added.

According to CSIRO researcher and co-author Dr Cara Doherty, the team’s new cactus-inspired solution offers an alternative. A cactus plant has tiny cracks, called stomatal pores, which open at night when it is cool and humid, and close during the day when the conditions are hot and arid. This helps it retain water,” Dr Doherty said. “This membrane works in a similar way. Water is generated by an electrochemical reaction, which is then regulated through nano-cracks within the skin. The cracks widen when exposed to humidifying conditions, and close up when it is drier. This means that fuel cells can remain hydrated without the need for bulky external humidifier equipment. We also found that the skin made the fuel cells up to four times as efficient in hot and dry conditions,” she added.

Professor Young Moo Lee from Hanyang University, who led the research, said that this could have major implications for many industries, including the development of electric vehicles.

Source: http://www.csiro.au/

Friendly Alternative To Li-Ion Battery

An unexpected discovery has led to a rechargeable battery that’s as inexpensive as conventional car batteries, but has a much higher energy density. The new battery could become a cost-effective, environmentally friendly alternative for storing renewable energy and supporting the power grid.

A team based at the Department of Energy’s Pacific Northwest National Laboratory (PNNL) identified this energy storage gem after realizing the new battery works in a different way than they had assumed. The journal Nature Energy published a paper today that describes the battery.

PNNL batteryPNNL’s improved aqueous zinc-manganese oxide battery offers a cost-effective, environmentally friendly alternative for storing renewable energy and supporting the power grid.

“The idea of a rechargeable zinc-manganese battery isn’t new; researchers have been studying them as an inexpensive, safe alternative to lithium-ion batteries since the late 1990s,” said PNNL Laboratory Fellow Jun Liu, the paper’s corresponding author. “But these batteries usually stop working after just a few charges. Our research suggests these failures could have occurred because we failed to control chemical equilibrium in rechargeable zinc-manganese energy storage systems.”

After years of focusing on rechargeable lithium-ion batteries, researchers are used to thinking about the back-and-forth shuttle of lithium ions. Lithium-ion batteries store and release energy through a process called intercalation, which involves lithium ions entering and exiting microscopic spaces in between the atoms of a battery’s two electrodes.

This concept is so engrained in energy storage research that when PNNL scientists, collaborating with the University of Washington, started considering a low-cost, safe alternative to lithium-ion batteries − a rechargeable zinc-manganese oxide battery − they assumed zinc would similarly move in and out of that battery’s electrodes. After a battery of tests, the team was surprised to realize their device was undergoing an entirely different process. Instead of simply moving the zinc ions around, their zinc-manganese oxide battery was undergoing a reversible chemical reaction that converted its active materials into entirely new ones.

Source: http://www.pnnl.gov/

How To Harvest Heat In The Dark To Produce Electricity

Physicists have discovered radical new properties in a nanomaterial, opening new possibilities for highly efficient thermophotovoltaic cells that could one day harvest heat in the dark and turn it into electricity. The research team from the Australian National University (ANU/ARC Centre of Excellence CUDOS) and the University of California Berkeley demonstrated a new artificial material, or metamaterial, that glows in an unusual way when heated.

The findings could drive a revolution in the development of cells which convert radiated heat into electricity, known as thermophotovoltaic cells. “Thermophotovoltaic cells have the potential to be much more efficient than solar cells,” said Dr Sergey Kruk from the ANU Research School of Physics and Engineering.

thermophotovoltaic

Our metamaterial overcomes several obstacles and could help to unlock the potential of thermophotovoltaic cells.”

Thermophotovoltaic cells have been predicted to be more than twice as efficient as conventional solar cells. They do not need direct sunlight to generate electricity, and instead can harvest heat from their surroundings in the form of infrared radiation. They can also be combined with a burner to produce on-demand power or can recycle heat radiated by hot engines. The team’s metamaterial, made of tiny nanoscopic structures of gold and magnesium fluoride, radiates heat in specific directions. The geometry of the metamaterial can also be tweaked to give off radiation in specific spectral range, in contrast to standard materials that emit their heat in all directions as a broad range of infrared wavelengths. This makes the new material ideal for use as an emitter paired with a thermophotovoltaic cell.

The project started when Dr Kruk predicted the new metamaterial would have these surprising properties. The ANU team then worked with scientists at the University of California Berkeley, who have unique expertise in manufacturing such materials.

To fabricate this material the Berkeley team were operating at the cutting edge of technological possibilities,” Dr Kruk said. “The size of an individual building block of the metamaterial is so small that we could fit more than 12,000 of them on the cross-section of a human hair.

The research is published in Nature Communications.

Source: http://www.anu.edu.au/

Battery That Could Be Recharged 200,000 Times

Scientists have long sought to use nanowires in batteries. Thousands of times thinner than a human hair, they’re highly conductive and feature a large surface area for the storage and transfer of electrons. However, these filaments are extremely fragile and don’t hold up well to repeated discharging and recharging, or cycling. In a typical lithium-ion battery, they expand and grow brittle, which leads to cracking.

Researchers fron the University of California Irvine (UCI) have solved this problem by coating a gold nanowire in a manganese dioxide shell and encasing the assembly in an electrolyte made of a Plexiglas-like gel. The combination is reliable and resistant to failure.

Mya Le Thai

The study leader, UCI doctoral candidate Mya Le Thai, cycled the testing electrode up to 200,000 times over three months without detecting any loss of capacity or power and without fracturing any nanowires. The findings were published today in the American Chemical Society’s Energy Letters. Hard work combined with serendipity paid off in this case, according to senior author Reginald Penner.

Mya was playing around, and she coated this whole thing with a very thin gel layer and started to cycle it,” said Penner, chair of UCI’s chemistry department. “She discovered that just by using this gel, she could cycle it hundreds of thousands of times without losing any capacity”.

That was crazy,” he added, “because these things typically die in dramatic fashion after 5,000 or 6,000 or 7,000 cycles at most.

Source: https://news.uci.edu/

Root, the Code-Teaching Robot

In the digital age, computing fuels some of the fastest-growing segments of the economy, making programming an increasingly important part of an American education. But the words “computer literacy” do not exactly excite the imaginations of most grade schoolers. So how to engage young minds with coding? One answer, say researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering, is a robot named Root.

Root teaches kids codingCLICK ON THE IMAGE TO ENJOY THE VIDEO

“Right now, coding is taught at a computer keyboard. It’s an abstract process that doesn’t have a relationship to the real world,” said Raphael Cherney, a research associate at the institute. “What Root does is bring coding to life in an extremely fun and approachable way. Kids with no experience in coding can be programming robots in a matter of minutes.

Fitting somewhere between old-time remote-controlled toy trains and today’s video games, Root is a robot that is programmed using a tablet interface called Square. Root has light and color sensors, bumpers, and a touch surface that enable it to respond to the physical world. In a classroom setting, Root would “drive” along a magnetic dry-erase whiteboard at the front of the class, giving the young programmers an “instant, physical manifestation” of the code, according to Zivthan Dubrovsky, who leads the robotics platform at Wyss.
Source: http://news.harvard.edu/

Brain Implant Moves Paralyzed Arm

This is Ian Burkhart of Ohio. His hands and legs were permanently paralyzed in a diving accident when he was 19 years old. But now with the help of a new, breakthrough computer chip implanted in his brain – the, now, 24-year-old is playing guitar hero.

brain implant helps paralized limbsCLICK ON THE IMAGE TO ENJOY THE VIDEO
When we first hooked everything up, you know for the first time being able to move my hand, it was a big shock because you know it was something that I have not moved in three and half years at that point, now it’s more of something where I expect it to move“,  says  Ian Burkhat, the quadriplegic patient at Ohio State University Wexner Medical Center.  The small pea-sized computer chip relays signals from Burkhart’s brain through 130 electrodes to his forearm, allowing his mind guide his hands and fingers, bypassing his damaged spinal cord. On Wednesday, scientists and neurosurgeons describing this quadriplegic’s accomplishments as a milestone in the evolution of brain-computer interface technology.

This really provides hope, we believe, for many patients in the future as this technology evolves and matures“, comments Doctor Ali Rezai, from the Ohio State’s Center for NeuroModulation. Burkhart says the progress is moving along faster than he imagined: “The biggest dream would be to get full function of my hand back, both my hands, because that would allow you to be much more independent, not to have to rely on people for simple day to day tasks that you take for granted.”

Scientists are working to improve the technology, which for now can only be used in the laboratory, and move toward a wireless system bringing Burkhart another step closer to his dream.

Source: http://wexnermedical.osu.edu/

Robots That Feel And Touch Like Humans

Smart synthetic skins have the potential to allow robots to touch and sense what’s around them, but keeping them powered up and highly sensitive at low cost has been a challenge. Now scientists report in the journal ACS Nano a self-powered, transparent smart skin that is simpler and less costly than many other versions that have been developed.

mother robot

Endowing robots and prosthetics with a human-like sense of touch could dramatically advance these technologies. Toward this goal, scientists have come up with various smart skins to layer onto devices. But boosting their sensitivity has involved increasing the numbers of electrodes, depending on the size of the skin. This leads to a rise in costs. Other systems require external batteries and wires to operate, which adds to their bulk. Haixia Zhang and colleagues wanted to find a more practical solution.

The researchers created a smart skin out of ultra-thin plastic films and just four electrodes made from silver nanowires. Other prototypes contain up to 36 electrodes. Additionally, one component harvests mechanical energy — for example, from the movement of a prosthetic hand’s fingers — and turns it into an electric current.

Source: http://www.acs.org/

Electronic Circuits Applied To Paper From A Pen

The electronics of the future will be printed. Flexible circuits can be produced inexpensively on foil or paper using printing processes and permit futuristic designs with curved diodes or input elements. This requires printable electronic materials that can be printed and retain a high level of conductivity during usage in spite of their curved surfaces. Some tried and tested materials include organic, conductive polymers and nanoparticles made of conductive oxides (TCOs). Research scientists at INMLeibniz-Institute for New Materials (Germany) have now combined the benefits of organic and inorganic electronic materials in a new type of hybrid inks. This allows electronic circuits to be applied to paper directly from a pen, for example. To create their hybrid inks, the research scientists coated nanoparticles made of metals with organic, conductive polymers and suspended them in mixtures of water and alcohol. These suspensions can be applied directly on paper or foil using a pen and they dry without any further processing to form electrical circuits.

ink to print electronics

Electrically conductive polymers are used in OLEDs, for example, which can also be manufactured on flexible substrates,” explains Tobias Kraus, Head of the research group Structure Formation at INM. “The combination of metal and nano-particles that we introduce here combines mechanical flexibility with the robustness of a metal and increases the electrical conductivity.”

The developers will be demonstrating their results and the possibilities they offer at stand B46 in hall 2 at this year’s Hanover Trade Fair as part of the leading trade show Research & Technology which takes place from 25th to 29th April.

Source: http://www.leibniz-inm.de/

Nanotechnology Improves Next Generation Of Batteries

In the global race to create more efficient and long-lasting batteries, some are betting on nanotechnology — the use of minuscule parts — as the most likely to yield a breakthrough. Improving batteries’ performance is key to the development and success of many much-hyped technologies, from solar and wind energy to electric cars. They need to hold more energy, last longer, be cheaper and safer. Research into how to achieve that has followed several avenues, from using different materials than the existing lithium-ion batteries to changing the internal structure of batteries using nanoparticles — parts so small they are invisible to the naked eye. Nanotechnology can increase the size and surface of batteries electrodes, the rods inside the batteries that absorb the energy. It does so by effectively making the electrodes sponge-like, so that they can absorb more energy during charging and ultimately increasing the energy storage capacity. Prague-based company HE3DA in Czech Republic has developed such a technology by using the nanotechnology to move from the current flat electrodes to make them three dimensional. With prototypes undergoing successful testing, it hopes to have the battery on the market at the end of this year.

Tesla Model 3

In the future, this will be the mainstream,” said Jan Prochazka, the president. He said it would be targeted at high-intensity industries like automobiles and the energy sector, rather than mobile phones, because that is where it can make the biggest difference through its use of his bigger electrodes.

In combination with an internal cooling system the batteries, which are being tested now, should be safe from overheating or exploding, a major concern with existing technologies. Researchers at the University of Michigan and MIT have likewise focused on nanotechnology to improve the existing lithium-ion technology. Others have sought to use different materials. One of the most promising is lithium oxygen, which theoretically could store five to 10 times the energy of a lithium ion battery, but there have been a number of technical problems that made it inefficient. Batteries based on sodium-ion, aluminium-air and aluminium-graphite are also being explored. There’s even research on a battery powered by urine.

Source: http://www.he3da.cz/
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http://bigstory.ap.org/

Electric Car: Safer, Cheaper Rechargeable Batteries

By chemically modifying and pulverizing a promising group of compounds, scientists at the National Institute of Standards and Technology (NIST) have potentially brought safer, solid-state rechargeable batteries two steps closer to reality.

sodiumChunks of this sodium-based compound (Na2B12H12) (left) would function well in a battery only at elevated temperatures, but when they are milled into far smaller pieces (right), they can potentially perform even in extreme cold, making them even more promising as the basis for safer, cheaper rechargeables.

These compounds are stable solid materials that would not pose the risks of leaking or catching fire typical of traditional liquid battery ingredients and are made from commonly available substances. Since discovering their properties in 2014, a team led by NIST scientists has sought to enhance the compounds’ performance further in two key ways: Increasing their current-carrying capacity and ensuring that they can operate in a sufficiently wide temperature range to be useful in real-world environments.

Considerable advances have now been made on both fronts, according to Terrence Udovic of the NIST Center for Neutron Research, whose team has published a pair of scientific papers that detail each improvement.  The first advance came when the team found that the original compounds — made primarily of hydrogen, boron and either lithium or sodium — were even better at carrying current with a slight change to their chemical makeup. Replacing one of the boron atoms with carbon improved their ability to conduct charged particles, or ions, which are what carry electricity inside a battery. As the team reported in February in their first paper, the switch made the compounds about 10 times better at conducting.

But perhaps more important was clearing the temperature hurdle. The compounds conducted ions well enough to operate in a battery — as long as it was in an environment typically hotter than boiling water. Unfortunately, there’s not much of a market for such high-temperature batteries, and by the time they cooled to room temperature, the materials’ favorable chemical structure often changed to a less conductive form, decreasing their performance substantially. One solution turned out to be crushing the compounds’ particles into a fine powder.

This approach can remove worries about whether batteries incorporating these types of materials will perform as expected even on the coldest winter day,” said Udovic, whose collaborators on the most recent paper include scientists from Japan’s Tohoku University, the University of Maryland and Sandia National Laboratories. “We are currently exploring their use in next-generation batteries, and in the process we hope to convince people of their great potential.”

Source: http://nist.gov

Cost-effective Hydrogen Production From Water

Groundbreaking research at Griffith University (Australia) is leading the way in clean energy, with the use of carbon as a way to deliver energy using hydrogen. Professor Xiangdong Yao and his team from Griffith’s Queensland Micro- and Nanotechnology Centre have successfully managed to use the element to produce hydrogen from water as a replacement for the much more costly platinum.

Tucson fuel cellTucson fom Hyundai: A Hydrogen Fuel Cell Car

Hydrogen production through an electrochemical process is at the heart of key renewable energy technologies including water splitting and hydrogen fuel cells,” says Professor Yao. “Despite tremendous efforts, exploring cheap, efficient and durable electrocatalysts for hydrogen evolution still remains a great challenge. “Platinum is the most active and stable electrocatalyst for this purpose, however its low abundance and consequent high cost severely limits its large-scale commercial applications. “We have now developed this carbon-based catalyst, which only contains a very small amount of nickel and can completely replace the platinum for efficient and cost-effective hydrogen production from water.

In our research, we synthesize a nickel–carbon-based catalyst, from carbonization of metal-organic frameworks, to replace currently best-known platinum-based materials for electrocatalytic hydrogen evolution“, he adds. “This nickel-carbon-based catalyst can be activated to obtain isolated nickel atoms on the graphitic carbon support when applying electrochemical potential, exhibiting highly efficient hydrogen evolution performance and impressive durability.”

Proponents of a hydrogen economy advocate hydrogen as a potential fuel for motive power including cars and boats and on-board auxiliary power, stationary power generation (e.g., for the energy needs of buildings), and as an energy storage medium (e.g., for interconversion from excess electric power generated off-peak).

Source: https://app.secure.griffith.edu.au/

Dye Solar Cells Make Your Mouse Battery Obsolete

These little glass squares could just be the answer to charging all your electronics. The glass-printed photovoltaic cells are a form of Dye Solar Cell technology created by Israeli company 3G Solar Photovoltaics. They’re so sensitive they can generate power from indirect, indoor lighting. Check it out. The company’s head of R&D Nir Stein is taking the batteries out of this mouse, which has the company’s dye solar cell module installed on top.


solar cells powered mouseCLICK ON THE IMAGE TO ENJOY THE VIDEO

What you see here is a computer mouse that has a bluetooth connectivity inside it and is powered by 3G solar photovoltaic cells. So when you have thousands of sensors, for instance in a building, which is going to happen in the next few years, you’ll never have to change a battery again,” says Nir Stein.
Dye-sensitized solar cells, or Graetzel cells, were discovered about 20 years ago. When they’re exposed to sunlight the dye becomes excited and creates an electronic charge without the need for pricey semiconductors. Kind of like the way plants use chlorophyll to turn sunlight into energy through photosynthesis. While the technology is the same, 3G Solar Voltaics‘ CEO Barry Breen says that being able to embed the cells on small surfaces has the potential to change the way we charge everyday devices. ) BARRY N. BREEN, CEO OF 3GSOLAR PHOTOVOLTAICS, SAYING: “What we offer in our cells, in our light power devices, is a solution that gives three times the power of anything else that exists, and we’re talking indoors, where most the electronics are used. So three times the power to run these new electronics, the new sensors, the smart watches and other wearables. So it’s a way to keep those powered that couldn’t be done before,” comments Barry Breen, CEO of 3G Solar Photovoltaics.

The small modules are durable and last for about 10 years. They can be colored and fitted to the shape of a device so they don’t stand out. Although still a prototype, the makers say the technology could make batteries a thing of the past.

Source: http://www.3gsolar.com/