Posts about battery

Large Scale Redox Flow Battery (700 megawatt hours)

Scientists and engineers in Germany have created the largest battery in the world with redox flow technology.

Redox flow batteries are liquid batteries. The Friedrich Schiller University of Jena has developed a new and forward-looking salt-free (brine) based metal-free redox flow battery. This new development will use salt caverns as energy storage.

schematic for salt-free (brine) based metal-free redox flow battery

Schematic for salt-free (brine) based metal-free redox flow battery by Ewe Gasspeicher. Two caverns each have a volume of 100,000 cubic meters.

A redox flow battery consists of two storage tanks and an electrochemical cell in which the reactions take place. Storage for solar and wind sources of power is an important challenge being explored in many ways today. Efforts such as this one provide a path to continue the rapid adoption of more solar and wind power.

In the electrochemical cell the two storage liquids – catholyte and anolyte – are separated from one another by a membrane. This prevents the large storage liquids from mixing with one another. The ions, however, can pass unimpeded through the membrane from one electrolyte solution into the other.

When charging the battery, the charging current ensures that electrons are deposited on the polymers of the anolyte. At the same time, the catholyte releases its electrons.

The charged catholyte and anolyte molecules are pumped from the cell into storage containers and replaced by uncharged ones. When the battery is discharged, the reaction is reversed. The anolyte molecules emit their electrons, which are available as electrical current.

Both charged electrolytes can be stored for several months. The maximum storage capacity of this redox-flow battery is limited only by the size of the storage containers for the electrolyte liquids.

The project is being ramped up now, going through a test phase before bringing the full system online; they are aiming to achieve this in 6 years. The electrical capacity of 700 megawatt hours will be enough to supply over 75,000 households with electricity for one day.

Related: Molten Salt Solar Reactor Approved by California (2010)Battery Breakthrough Using Organic Storage (2014)Chart of Global Wind Energy Capacity by Country from 2005 to 2015

Battery Breakthrough Using Organic Storage

Battery offers renewable energy breakthrough

a metal-free flow battery that relies on the electrochemistry of naturally abundant, inexpensive, small organic (carbon-based) molecules called quinones, which are similar to molecules that store energy in plants and animals.

The mismatch between the availability of intermittent wind or sunshine and the variable demand is the biggest obstacle to using renewable sources for a large fraction of our electricity. A cost-effective means of storing large amounts of electrical energy could solve this problem.

Flow batteries store energy in chemical fluids contained in external tanks, as with fuel cells, instead of within the battery container itself. The two main components — the electrochemical conversion hardware through which the fluids are flowed (which sets the peak power capacity) and the chemical storage tanks (which set the energy capacity) — may be independently sized. Thus the amount of energy that can be stored is limited only by the size of the tanks. The design permits larger amounts of energy to be stored at lower cost than with traditional batteries.

This looks like a very interesting field of research. Storing power remains one of the challenges for renewable energy sources such as solar and wind. This is especially true if the use is disconnected from the grid, but is even true for grid-connected uses. Especially as increasing the amount of wind and solar energy make it increasingly likely that surplus energy is created at certain times.

The research seems to allow for sensible size home storage setups. At the commercial level the volume needed is very large. Another concern to be addressed is how many cycles the “battery” is good for before it degrades; current experimentation show no degradation after 100 cycles but consumer/commercial usage will need thousands of cycles.

Related: Battery Breakthrough (solid sodium metal mated to a sulphur compound by an extraordinary, paper-thin ceramic membrane)Energy Storage Using Carbon Nanotubes (2006)Chart of Wind Power Generation Capacity Globally 2005-2012Recharge Batteries in Seconds

Battery Breakthrough

New battery could change world

Inside Ceramatec’s wonder battery is a chunk of solid sodium metal mated to a sulphur compound by an extraordinary, paper-thin ceramic membrane. The membrane conducts ions — electrically charged particles — back and forth to generate a current. The company calculates that the battery will cram 20 to 40 kilowatt hours of energy into a package about the size of a refrigerator, and operate below 90 degrees C.

This may not startle you, but it should. It’s amazing. The most energy-dense batteries available today are huge bottles of super-hot molten sodium, swirling around at 600 degrees or so. At that temperature the material is highly conductive of electricity but it’s both toxic and corrosive. You wouldn’t want your kids around one of these.

The essence of Ceramatec‘s breakthrough is that high energy density (a lot of juice) can be achieved safely at normal temperatures and with solid components, not hot liquid.

Ceramatec says its new generation of battery would deliver a continuous flow of 5 kilowatts of electricity over four hours, with 3,650 daily discharge/recharge cycles over 10 years. With the batteries expected to sell in the neighborhood of $2,000, that translates to less than 3 cents per kilowatt hour over the battery’s life. Conventional power from the grid typically costs in the neighborhood of 8 cents per kilowatt hour.

A small three-bedroom home in Provo might average, say, 18 kWh of electric consumption per day in the summer — that’s 1,000 watts for 18 hours. A much larger home, say five bedrooms in the Grandview area, might average 80 kWh, according to Provo Power.;Either way, a supplement of 20 to 40 kWh per day is substantial. If you could produce that much power in a day — for example through solar cells on the roof — your power bills would plummet.

Ceramatec’s battery breakthrough now makes that possible.

Clyde Shepherd of Alpine is floored by the prospect. He recently installed the second of two windmills on his property that are each rated at 2.4 kilowatts continuous output. He’s searching for a battery system that can capture and store some of that for later use when it’s calm outside, but he hasn’t found a good solution.

“This changes the whole scope of things and would have a major impact on what we’re trying to do,” Shepherd said. “Something that would provide 20 kilowatts would put us near 100 percent of what we would need to be completely independent. It would save literally thousands of dollars a year.”

Very interesting stuff. If they can take it from the lab to production this could be a great thing, I would like one.

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Using Virus to Build Batteries

MIT researchers have shown they can genetically engineer viruses to build both the positively and negatively charged ends of a lithium-ion battery. We have posted about similar things previously, for example: Virus-Assembled BatteriesUsing Viruses to Construct Electrodes and Biological Molecular Motors. New virus-built battery could power cars, electronic devices

Gerbrand Ceder of materials science and Associate Professor Michael Strano of chemical engineering, genetically engineered viruses that first coat themselves with iron phosphate, then grab hold of carbon nanotubes to create a network of highly conductive material.

Because the viruses recognize and bind specifically to certain materials (carbon nanotubes in this case), each iron phosphate nanowire can be electrically “wired” to conducting carbon nanotube networks. Electrons can travel along the carbon nanotube networks, percolating throughout the electrodes to the iron phosphate and transferring energy in a very short time. The viruses are a common bacteriophage, which infect bacteria but are harmless to humans.

The team found that incorporating carbon nanotubes increases the cathode’s conductivity without adding too much weight to the battery. In lab tests, batteries with the new cathode material could be charged and discharged at least 100 times without losing any capacitance. That is fewer charge cycles than currently available lithium-ion batteries, but “we expect them to be able to go much longer,” Belcher said.

This is another great example of university research attempting to find potentially valuable solutions to societies needs. See other posts on using virus for productive purposes.

Wireless Power

   
An end to spaghetti power cables by Maggie Shiels, BBC News

Mr Rattner envisaged a scenario where a laptop’s battery could be recharged when the machine gets within several feet of a transmit resonator which could be embedded in tables, work surfaces, picture frames and even behind walls.

Intel’s technology relies on an idea called magnetic induction. It is a principle similar to the way a trained singer can shatter a glass using their voice; the glass absorbs acoustic energy at its natural frequency. At the wall socket, power is put into magnetic fields at a transmitting resonator – basically an antenna. The receiving resonator is tuned to efficiently absorb energy from the magnetic field, whereas nearby objects do not.

Intel’s demonstration has built on work done originally by Marin Soljacic, a physicist at Massachusetts Institute of Technology (MIT). At the Intel Developer Forum in San Francisco, researcher Alanson Sample showed how to make a 60-watt light bulb glow from an energy source three feet away. This was achieved with relatively high efficiency, only losing a quarter of the energy it started with.

Don’t expect to see this available commercially this year, they estimate it is at least 5 years away. Though this is not university and business collaboration in the sense they are working together, it is in the sense that Intel is building upon the work MIT did. See other posts on university and business collaboration.

Related: Water From AirEngineers Save EnergyMicrochip Cooling Innovation

MIT Energy Storage Using Carbon Nanotubes

Images of different types of carbon nanotubes

MIT Researchers Fired up Over New Battery

Image / Michael Ströck, Images of different types of carbon nanotubes. Carbon nanotubes are key to MIT researchers’ efforts to improve on an energy storage device called an ultracapacitor. Larger image

Work at MIT’s Laboratory for Electromagnetic and Electronic Systems (LEES) holds out the promise of the first technologically significant and economically viable alternative to conventional batteries in more than 200 years.

The LEES ultracapacitor has the capacity to overcome this energy limitation by using vertically aligned, single-wall carbon nanotubes — one thirty-thousandth the diameter of a human hair and 100,000 times as long as they are wide. How does it work? Storage capacity in an ultracapacitor is proportional to the surface area of the electrodes. Today’s ultracapacitors use electrodes made of activated carbon, which is extremely porous and therefore has a very large surface area. However, the pores in the carbon are irregular in size and shape, which reduces efficiency. The vertically aligned nanotubes in the LEES ultracapacitor have a regular shape, and a size that is only several atomic diameters in width. The result is a significantly more effective surface area, which equates to significantly increased storage capacity.