The Death Of Oil: Scientists Eyeball 2X EV Battery Range


For someone who’s all in for fossil fuels, President* Trump sure has a thing for electric vehicles.

Last October the US Energy Department announced $15 million in funding to jumpstart the next generation of “extremely” fast charging systems, and last week the agency’s SLAC National Accelerator Laboratory announced a breakthrough discovery for doubling the range of EV batteries.

Put the two together, and you have EVs that can go farther than any old car, and fuel up just about as quickly.

Add the convenience factor of charging up at home or at work, and there’s your recipe for killing oil. #ThanksTrump!

A Breakthrough Energy Storage Discovery For Electric Vehicles

Did you know that it’s possible to double the range of today’s electric vehicles?

No, really! The current crop of  lithium-ion batteries use just half of their theoretical capacity, so there is much room for improvement.

To get closer to 100%, all you have to do is “overstuff” the positive electrode — the cathode — with more lithium. Theoretically, that would enable the battery to absorb more ions in the same space. Theoretically.

Unfortunately, previous researchers have demonstrated that supercharged cathodes lose voltage too quickly to be useful in EVs, because their atomic structure changes.

During the charge cycle, lithium ions leave the supercharged cathode and transition metal atoms move in. When the battery discharges, not all of the transition metal atoms go back to where they came from, leaving less space for the lithium ions to return.

It’s kind of like letting two friends crash on your couch, and one of them never leaves.

That’s the problem tackled by a research team based at the SLAC National Accelerator Laboratory (SLAC is located at Stanford University and the name is a long story involving some trademark issues, but apparently it’s all good now).

Here’s Stanford grad student and study leader William E. Gent enthusing over the new breakthrough:

It gives us a promising new pathway for optimizing the voltage performance of lithium-rich cathodes by controlling the way their atomic structure evolves as a battery charges and discharges.

Umm, okay.

In other words, the SLAC team discovered a way to manipulate the atomic structure of supercharged cathodes, so the battery doesn’t lose voltage during the charge/discharge cycle.

And, here’s where oil dies:

The more ions an electrode can absorb and release in relation to its size and weight — a factor known as capacity — the more energy it can store and the smaller and lighter a battery can be, allowing batteries to shrink and electric cars to travel more miles between charges.

No, Really — How Does It Work?

To get to the root of the problem, the research team deployed some fancy equipment at  SLAC’s SSRL (Stanford Synchotron Radiation Lightsource) to track the atomic-level changes that a lithium-rich battery undergoes during charging cycles.

First, they defined the problem:

…clarifying the nature of anion redox and its effect on electrochemical stability requires an approach that simultaneously probes the spatial distribution of anion redox chemistry and the evolution of local structure.

The research team “unambiguously confirmed” the interplay between oxygen and the transition metal, along with the mechanism for controlling that reaction:

Our results further suggest that anion redox chemistry can be tuned through control of the crystal structure and resulting TM migration pathways, providing an alternative route to improve Li-rich materials without altering TM–O bond covalency through substitution with heavier 4d and 5d TMs.

The equipment angle is essential, btw. Apparently, until the new SLAC study nailed it down there was widespread disagreement on the root cause of the problem.

The new research was made possible in part by a new soft X-ray RIXS system, which was just installed at the lab last year (RIX stands for resonant inelastic X-ray scattering).

You can get all the details from the study, “Coupling between oxygen redox and cation migration explains unusual electrochemistry in lithium-rich layered oxides,” which just came out in the journal Nature Communications.

So, Now What?

The SLAC team points out that until now, RIXS has been mainly used in foundational research. The new study goes a long way to confirming the practical application of RIXS.

In other words, the floodgates are open to a new wave of advanced energy storage research leading to better, cheaper EV batteries and faster charging systems.

In that regard its worth noting that along with the Energy Department, Samsung partnered in the new study and chipped in some of the funding.

That’s a pretty clear indication that Samsung is looking to crack open the Panasonic/Tesla partnership and take over global leadership of the energy storage field. Last September, Samsung unveiled a new 600-km (430-mile) battery for EVs, but the company was mum on the details.

Last November, Samsung unveiled a new version of its SM3 ZE sedan, in which the size of the battery was doubled without increasing the weight of the vehicle. That’s a significant achievement and the company has been tight-lipped on that score, too.

Samsung is also exploring graphene for advanced, long range batteries, so there’s that.

“Perhaps News of My (Oil) premature Death has been misreported”

As for the death of oil, electric vehicles are getting their place in the sun, no matter how much Trump talks up fossil fuels.

That still leaves the issue of petrochemicals.

Although the green chemistry movement is gathering steam, the US petrochemical industry has been taking off like a rocket in recent years. That means both oil and natural gas production could continue apace for the foreseeable future, with or without gasmobiles.

ExxonMobil has been making huge moves into the Texas epicenter of US petrochemicals, and just last week the Houston Chronicle noted this development:

Michigan and Delware-based DowDuPont announced earlier this year that it would spend $4 billion expanding its industrial campus in Freeport.

The expansion will give Freeport the largest ethylene plant in the world. Houston-based Freeport LNG is also building an LNG export terminal in the area.

Then there’s this:

By 2019, Freeport’s power demand is expected to be 92 percent higher than it was in 2016, according to ERCOT.

The $246.7 million project will include a new 48 mile transmission line and upgrades to shorter line in the area, according to ERCOT.

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Scientists Invent Self-healing Battery Electrode


3D rendered Molecule (Abstract) with Clipping PathMenlo Park, Calif. — Researchers have made the first battery electrode that heals itself, opening a new and potentially commercially viable path for making the next generation of lithium ion batteries for electric cars, cell phones and other devices. The secret is a stretchy polymer that coats the electrode, binds it together and spontaneously heals tiny cracks that develop during battery operation, said the team from Stanford University and the Department of Energy’s (DOE) SLAC National Accelerator Laboratory.

They report the advance in the Nov. 19 issue of Nature Chemistry.

SELFHEALING-Electrode

This prototype lithium ion battery, made in a Stanford lab, contains a silicon electrode protected with a coating of self-healing polymer. The cables and clips in the background are part of an apparatus for testing the performance of batteries during multiple charge-discharge cycles. (Brad Plummer/SLAC)

Self-healing is very important for the survival and long lifetimes of animals and plants,” said Chao Wang, a postdoctoral researcher at Stanford and one of two principal authors of the paper. “We want to incorporate this feature into lithium ion batteries so they will have a long lifetime as well.”

Chao developed the self-healing polymer in the lab of Stanford Professor Zhenan Bao, whose group has been working on flexible electronic skin for use in robots, sensors, prosthetic limbs and other applications. For the battery project he added tiny nanoparticles of carbon to the polymer so it would conduct electricity.

”We found that silicon electrodes lasted 10 times longer when coated with the self-healing polymer, which repaired any cracks within just a few hours,” Bao said.

“Their capacity for storing energy is in the practical range now, but we would certainly like to push that,” said Yi Cui, an associate professor at SLAC and Stanford who led the research with Bao. The electrodes worked for about 100 charge-discharge cycles without significantly losing their energy storage capacity. “That’s still quite a way from the goal of about 500 cycles for cell phones and 3,000 cycles for an electric vehicle,” Cui said, “but the promise is there, and from all our data it looks like it’s working.”

Researchers worldwide are racing to find ways to store more energy in the negative electrodes of lithium ion batteries to achieve higher performance while reducing weight. One of the most promising electrode materials is silicon; it has a high capacity for soaking up lithium ions from the battery fluid during charging and then releasing them when the battery is put to work.

But this high capacity comes at a price: Silicon electrodes swell to three times normal size and shrink back down again each time the battery charges and discharges, and the brittle material soon cracks and falls apart, degrading battery performance. This is a problem for all electrodes in high-capacity batteries, said Hui Wu, a former Stanford postdoc who is now a faculty member at Tsinghua University in Beijing, the other principal author of the paper.

To make the self-healing coating, scientists deliberately weakened some of the chemical bonds within polymers – long, chain-like molecules with many identical units. The resulting material breaks easily, but the broken ends are chemically drawn to each other and quickly link up again, mimicking the process that allows biological molecules such as DNA to assemble, rearrange and break down.

To show how flexible their self-healing polymer is, researchers coated a balloon with it and then inflated and deflated the balloon repeatedly, mimicking the swelling and shrinking of a silicon electrode during battery operation. The polymer stretches but does not crack. (Brad Plummer/SLAC)

Researchers in Cui’s lab and elsewhere have tested a number of ways to keep silicon electrodes intact and improve their performance. Some are being explored for commercial uses, but many involve exotic materials and fabrication techniques that are challenging to scale up for production.

The self-healing electrode, which is made from silicon microparticles that are widely used in the semiconductor and solar cell industries, is the first solution that seems to offer a practical road forward, Cui said. The researchers said they think this approach could work for other electrode materials as well, and they will continue to refine the technique to improve the silicon electrode’s performance and longevity.

The research team also included Zheng Chen and Matthew T. McDowell of Stanford. Cui and Bao are members of the Stanford Institute for Materials and Energy Sciences, a joint SLAC/Stanford institute. The research was funded by DOE through SLAC’s Laboratory Directed Research and Development program and by the Precourt Institute for Energy at Stanford University.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the U.S. Department of Energy Office of Science. To learn more, please visit www.slac.stanford.edu.

The Stanford Institute for Materials and Energy Sciences (SIMES) is a joint institute of SLAC National Accelerator Laboratory and Stanford University. SIMES studies the nature, properties and synthesis of complex and novel materials in the effort to create clean, renewable energy technologies. For more information, please visit simes.slac.stanford.edu.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Citation: C. Wang et al., Nature Chemistry, 17 October 2013 (10.1038/nchem.1802)