A powerful new material developed by Northwestern University chemist William Dichtel and his research team could one day speed up the charging process of electric cars and help increase their driving range. An electric car currently relies on a complex interplay of both batteries and supercapacitors to provide the energy it needs to go places, but that could change.

“Our material combines the best of both worlds – the ability to store large amounts of electrical energy or charge, like a battery, and the ability to charge and discharge rapidly, like a supercapacitor,” said Dichtel, a pioneer in the young research field of covalent organic frameworks (COFs).

Dichtel and his research team have combined a COF – a strong, stiff polymer with an abundance of tiny pores suitable for storing energy – with a very conductive material to create the first modified redox-active COF that closes the gap with other older porous carbon-based electrodes.

“COFs are beautiful structures with a lot of promise, but their conductivity is limited,” Dichtel said. “That’s the problem we are addressing here. By modifying them – by adding the attribute they lack – we can start to use COFs in a practical way.”

And modified COFs are commercially attractive: COFs are made of inexpensive, readily available materials, while carbon-based materials are expensive to process and mass-produce.

Dichtel, the Robert L. Letsinger Professor of Chemistry at the Weinberg College of Arts and Sciences, is presenting his team’s findings today (Aug. 24) at the American Chemical Society (ACS) National Meeting in Philadelphia. Also today, a paper by Dichtel and co-authors from Northwestern and Cornell University was published by the journal ACS Central Science.

To demonstrate the new material’s capabilities, the researchers built a coin-cell battery prototype device capable of powering a light-emitting diode for 30 seconds.

The material has outstanding stability, capable of 10,000 charge/discharge cycles, the researchers report. They also performed extensive additional experiments to understand how the COF and the conducting polymer, called poly(3,4-ethylenedioxythiophene) or PEDOT, work together to store electrical energy.

Dichtel and his team made the material on an electrode surface. Two organic molecules self-assembled and condensed into a honeycomb-like grid, one 2-D layer stacked on top of the other. Into the grid’s holes, or pores, the researchers deposited the conducting polymer.

Each pore is only 2.3 nanometers wide, but the COF is full of these useful pores, creating a lot of surface area in a very small space. A small amount of the fluffy COF powder, just enough to fill a shot glass and weighing the same as a dollar bill, has the surface area of an Olympic swimming pool.

The modified COF showed a dramatic improvement in its ability to both store energy and to rapidly charge and discharge the device. The material can store roughly 10 times more electrical energy than the unmodified COF, and it can get the electrical charge in and out of the device 10 to 15 times faster.

“It was pretty amazing to see this performance gain,” Dichtel said. “This research will guide us as we investigate other modified COFs and work to find the best materials for creating new electrical energy storage devices.”

Journal reference:

“Superior Charge Storage and Power Density of a Conducting Polymer-Modified Covalent Organic Framework.” In addition to Dichtel, other authors are Ryan P. Bisbey, of Northwestern; Catherine R. Mulzer (nee DeBlase, first author), currently at Dow Electronic Materials; and Luxi Shen, James R. McKone, Na Zhang and Hector D. Abruna, of Cornell.

(Source:  www.energy-daily.com; Aug 26, 2016; http://tinyurl.com/guk3v52)

Energy storage is crucial for taking full advantage of solar power, which otherwise suffers interruptions from cloudy skies and nightfall. In the past few years, concentrating solar power plants have begun producing additional electricity at night and during peak demand periods by using stored heat energy to propel a steam turbine.

Current thermal energy storage systems rely on materials that store less energy per kilogram, requiring more material at a greater cost to meet energy storage requirements.

Now, researchers at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory have designed an inexpensive thermal energy storage system that will be significantly smaller and perform more than 20 times better than current thermal systems.

With funding from DOE’s SunShot Initiative, the Argonne team is building a pilot-scale prototype of their high-efficiency latent heat thermal energy storage system (LHTES) for testing. The SunShot Initiative is a national collaborative effort to make unsubsidized solar energy cost-competitive with other forms of electricity production by 2020.

Argonne’s thermal energy storage system relies on a “phase-change” material that melts as it stores thermal energy and releases energy as it re-freezes — similar to the charge-discharge cycle in a battery.

Inexpensive salts like rock salt (sodium chloride) can be used as phase-change materials, but their use in existing thermal storage systems is limited because of the poor thermal conductivity of the salts.

However, the Argonne LHTES system drastically improves the conductivity of these salts by integrating them with a high-conductivity graphite foam. This combination reduces the overall amount of material needed to build the system and its cost, while making the thermal energy transfer significantly more efficient and still providing up to 8 to 12 hours of energy storage — a typical night of storage for a concentrating solar power plant.

“Phase-change materials tend to have low conductivity but meet the heat energy storage requirements,” said Dileep Singh, leader of Argonne’s Thermal-Mechanical Technologies group. “High-conductivity graphite foam meets the conductivity requirements, so we thought: why not combine the two?”

The porous graphite foam traps the salts in pores, facilitating rapid melting and freezing. The team demonstrated that this rapid phase change holds up over time. After building and testing an initial prototype about the size of a blender, the team is now scaling up the prototype size by 50 times.

Although still smaller than a full-scale power plant system, the pilot-scale modular system will be tested this fall and could expand on applications, such as providing back-up power on a microgrid or storing waste heat from another energy source. The pilot system will also further improve 3-D thermal modeling used for estimating performance and planning the design of a full-scale system.

“We are looking at developing the full-scale power plant system as a modular system, and the pilot-scale system we are building this year can actually be used as one module within a full-scale system that is made of many modules stacked or organized together,” said Argonne mechanical engineer Wenhua Yu. “Therefore, the performance characteristics we will measure from testing the pilot can directly reflect those of a power plant system.”

The full-scale design is expected to meet the needs of current power plants that operate steam turbines at about 450 to 600 degrees Celsius (850-1100 degrees Fahrenheit) using magnesium chloride as the storage medium. When advanced supercritical carbon dioxide turbines — which are more efficient than steam turbines but operate at a hotter 700 degrees Celsius (1,300 degrees Fahrenheit) — come online, the same design can be used with sodium chloride.

(Source:  sciencedaily.com; September 12, 2016; http://tinyurl.com/jur5h54)

Hi Everyone!
It’s James. Please watch the video above for a look into the present and final stage of our prototype development; QEG power conversion of VARs into usable watts.

Just a quick preamble… A few months after we opensourced the preliminary plans for the machine in March of 2014, we were astounded to realize that no one to date had actually been successful in making a viable self-sustaining electric power supply available for people to learn about and build if they wanted to take on the challenge. We could hardly believe it! We were so naïve!

Having studied Tesla and others, we knew the technology was there, but we didn’t realize the depth of the suppression, greed and control being exerted by the big energy companies, governments, and corporations in their efforts to maintain the status quo (read about Internet trolling activities HERE).

Now all of you who had the faith to stand behind this project, will have a tool with which to fight back, and we want to ask you to keep the spirit of the endeavor in mind. If this is truly a first, as it appears to be (at least in an open environment), we all have a responsibility.

We’ve taken steps to ensure that the QEG will not go the way of previous suppressed technology. When it’s time, we’ll publish several anonymous videos of self-looping machines. We cannot say when this will happen, hopefully soon, but it will happen. Many are building and completing their machines with me.

Please watch the video above for a look into the present and final stage of the prototype development; QEG power conversion of VARs into usable watts. And as always, the FTW/QEG Team thanks YOU for your continued interest in this grassroots, DIY engineering feat!

Once tuned, the QEG’s sinusoidal output energy is a combination of AC, RF, and radiant impulses, which will drive standard loads equivalent to 3kW (guaranteed) up to 10kW RMS or more, depending on the level of tuning. The output frequency I’m running is 150Hz, which is the ½ harmonic of the M19 core steel’s resonant frequency of 300Hz (this may be different for your machine depending on steel type used), and this is the frequency (150Hz) that has to be converted to 50 or 60HZ to be usable as your electrical mains. The output voltage is dependent upon whether the secondary output is wired in series or parallel, and will likely be 300-350 VAC for series wiring, and 150-200 VAC for parallel. Since people seem to expect a COP rating (which is really inappropriate for a self-sustained machine), I have guaranteed output of at least COP 3.9 based on the ratio of motor input power (768 Watts or 1 HP) to total output power (3000/768=3.90625), or at least 3kW RMS output.

How much power does a QEG produce? The QEG Tuning Video (3hrs) explains the tuning procedure and how to increase the power output on the QEG: