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Waste fibers from hemp crops out-perform graphene for a thousandth of the cost, according to new researchIs there anything hemp can’t do? A year after hemp became legal to grow in the United States, we’ve seen its power to make better clothing, better buildings and better medicine. Now, there’s something else hemp appears to be better at – making batteries. Most auto batteries today are made from lithium-ion, an expensive, quickly disappearing material. A team of American and Canadian researchers have developed a battery that could be used in cars and power tools using hemp bast fiber – the inner...

Schematic depiction of the asymmetric supercapacitor with the porous COF as the negative electrode shown on the left. Credit: KAUST, Osama Shekhah ========================================================================= Carefully designed covalent organic frameworks could make supercapacitor electrodes that have a greater ability to store electric charge. A porous organic material created at KAUST could significantly improve energy storage and delivery by supercapacitors, which are devices that are able to deliver quick and powerful bursts of energy. Supercapacitors use technology that is significantly different from the reversible chemical reactions used in rechargeable batteries. They store electrical energy by building up a separation of positive and electric...

Dresses emitting sparkling light from hundreds of small LEDs may create eye-catching effects in ballrooms or on fashion shows. But wearable electronics can also mean sensors integrated in functional textiles to monitor, for example, water evaporation or temperature changes. Energy storage systems powering such wearable devices must combine deformability with high capacity and durability. However, deformable electrodes often fail in long-term operation, and their capacity lags behind that of other state-of-the-art energy storage devices. Electrode materials usually benefit from a fine balance of porosity, conductivity, and electrochemical activity. Material scientists...have looked deeper into the material demands for flexible electrodes and...

The company has big plans to make electric cars cool. t’s an exciting time for solid state batteries. BMW announced last month that it’s teamed up with Colorado-based battery developer Solid Power, which could see the automaker ditch the liquid electrolyte lithium-ion cells of yesteryear in favor of a solid alternative that’s safer, higher-energy, and simpler. “I don’t wanna sit here and claim that all the technical challenges are solved,” Doug Campbell, the CEO of Solid Power, tells Inverse. “It’s a vote of confidence in that some of the fundamental historical concerns for solid state, I think this is a...

Israeli company Phinergy claim to have produced a battery that can power a Citroen C1 for 3000km, and have demonstrated a 1800km drive with a more practical version, three times that available from commercial electric cars. Even more dramatically, the battery weighs just 100km, a fifth of the weight of those in the Tesla Model S. Metal-air batteries use the oxygen in the air around them, rather than storing it in liquid or solid chemicals. They can store far more energy than most competing technologies. Not needing to contain the oxygen can also cut the weight dramatically – Phinergy claim...

Comprised of a lone hexagonal honeycomb lattice layer of tightly packed carbon atoms, graphene is one of the strongest, lightest, and most conductive compounds ever discovered. Bottom line, it's an extraordinary composite. However, a scientist from New York's Clarkson University says he's found a way to manufacture hemp waste into a material "better than graphene." Moreover, the scientist -- known to his peers as Dr. David Mitlin -- says creating this graphene-like hemp material costs but a minuscule fraction of what it takes to produce graphene. Presented at an American Chemical Society Meeting in San Francisco, Dr. Mitlin described how...

As hemp makes a comeback in the U.S. after a decades-long ban on its cultivation, scientists are reporting that fibers from the plant can pack as much energy and power as graphene, long-touted as the model material for supercapacitors, according to David Mitlin, Ph.D. Supercapacitors are energy storage devices that have huge potential to transform the way future electronics are powered. Unlike today’s rechargeable batteries, which sip up energy over several hours, supercapacitors can charge and discharge within seconds. But they normally can’t store nearly as much energy as batteries, an important property known as energy density. One approach researchers...

Flexible battery is paper-thin Last Updated: 12:01pm BST 14/08/2007 Paper and nanotechnology combine to create a new kind of battery, reports Roger HighfieldWhat looks to the untrained eye like thick, black paper is a novel flexible battery that could offer new opportunities for tomorrow's gadgets, from self propelling paper planes to smart pockets that can recharge a mobile phone.   The new nanocomposite paper developed by researchers at Rensselaer Polytechnic Institute Along with its ability to work in temperatures up to 150ºC (300ºF) and down to -70ºC (-100ºF), the battery can be printed like paper, rolled, twisted or folded, and even...

The dramatic rise of smartphones, tablets, laptops and other personal and portable electronics has brought battery technology to the forefront of electronics research. Even as devices have improved by leaps and bounds, the slow pace of battery development has held back technological progress. Now, researchers at UCLA's California NanoSystems Institute have successfully combined two nanomaterials to create a new energy storage medium that combines the best qualities of batteries and supercapacitors. Supercapacitors are electrochemical components that can charge in seconds rather than hours and can be used for 1 million recharge cycles. Unlike batteries, however, they do not store enough...

By dipping small pieces of an ordinary kitchen sponge into solutions of nanoscale electrode materials, scientists have created a light-weight, low-cost supercapacitor that benefits from the sponge's porous structure. The pores provide a large surface area for the electrode materials to attach to, leading to an increase in ion movement between the electrodes and the electrolyte that fills in the pores. Overall, the new supercapacitor exhibits a performance that is superior to that of one made of the same electrode materials but without the sponge. The researchers, led by Jun Ma at the University of South Australia, have published their...

Using porous silicon coated with graphene, material scientists at Vanderbilt University have developed the first supercapacitor that is made out of silicon. Solar cells that produce electricity 24/7, not just when the sun is shining. Mobile phones with built-in power cells that recharge in seconds and work for weeks between charges. These are just two of the possibilities raised by a novel supercapacitor design invented by material scientists at Vanderbilt University that is described in a paper published in the October 22 issue of the journal Scientific Reports. It is the first supercapacitor that is made out of silicon so...

Electrochemical capacitors (ECs), also known as supercapacitors or ultracapacitors, differ from regular capacitors that you would find in your TV or computer in that they store sustantially higher amounts of charges. They have garnered attention as energy storage devices as they charge and discharge faster than batteries, yet they are still limited by low energy densities, only a fraction of the energy density of batteries. An EC that combines the power performance of capacitors with the high energy density of batteries would represent a significant advance in energy storage technology. This requires new electrodes that not only maintain high conductivity...

Crab shells provide a cheap and convenient template to make high performance carbon electrodes for energy storage and conversion, say Chinese scientists. Carbon materials have many potential applications, including as electrodes in supercapacitors and fuel cells. The pore structure is known to affect their physicochemical properties and is normally controlled by using a porous hard template such as zeolite or silica. But the process usually involves using hydrofluoric acid to remove the templates, which can be complex and costly. A research group from Fudan University, led by Yong-Yao Xia, has demonstrated that crab shell has a well aligned porous structure at the microscopic level. Exploiting this...