Energy

Safe, fast-charging lithium battery handles 5 times the current

Safe, fast-charging lithium ba...
Scientists have made a breakthrough in the development of advanced lithium batteries that could enable them to charge faster and be less prone to failure
Scientists have made a breakthrough in the development of advanced lithium batteries that could enable them to charge faster and be less prone to failure
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Scientists have made a breakthrough in the development of advanced lithium batteries that could enable them to charge faster and be less prone to failure
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Scientists have made a breakthrough in the development of advanced lithium batteries that could enable them to charge faster and be less prone to failure
A diagram illustrating the function of a new battery anode developed at Texas A&M University
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A diagram illustrating the function of a new battery anode developed at Texas A&M University

Carefully introducing new materials into the design of today’s lithium-ion batteries has the potential to greatly improve their performance, and scientists have just happened upon a promising possibility in carbon nanotubes. By incorporating these materials into the electrode of a lithium metal battery, the researchers have produced a version that is not only safer, but has the potential to charge up in just a fraction of the time of conventional devices.

The research was carried out at Texas A&M University’s College of Engineering and centers on a battery architecture with huge potential. When a traditional lithium-ion battery charges and discharges, the lithium ions are ferried back and forth between the cathode and anode, the latter of which is usually made from a mix of graphite and copper.

But scientists see a great alternative in using pure lithium metal instead, which offers very high energy density and could make for batteries that charge much faster and offer as much as 10 times the capacity. One study last year described a lithium anode as “critical to break the energy density bottleneck of current li-ion chemistry." Suffice to say, there is considerable interest in making these things work.

Standing in the way, however, are dangly tentacles called dendrites. These tree-like structures build up on the surface of the anode when lithium ions aren’t evenly deposited and as they grow, they can pierce key components of the battery and cause it to short circuit and or catch fire. If that doesn’t occur, they cause the battery to quickly lose its charge anyway.

So a great deal of research centers on the problem of dendrite formation, and the Texas A&M team believes it may have found a solution in ultralight and highly conductive carbon nanotubes. The design mirrors that of another experimental battery we looked at in 2018 that uses a thin carbon nanotube film to effectively suffocate dendrites before they properly take shape, but the researchers behind the new study have taken a slightly different approach.

For its anode, the team used carbon nanotubes to build three-dimensional porous scaffolds laced with molecules that cause the lithium ions to bind to its surface. It took some experimentation, but with the right concentration of these binding molecules, the team found it had produced a battery anode that avoided the buildup of dendrites on its surface.

A diagram illustrating the function of a new battery anode developed at Texas A&M University
A diagram illustrating the function of a new battery anode developed at Texas A&M University

“But when we had just the right amount of these binding molecules, we could ‘unzip’ the carbon nanotube scaffolds at just certain places, allowing lithium ions to come through and bind on to the entire surface of the scaffolds rather than accumulate on the outer surface of the anode and form dendrites,” says study author Juran Noh.

Another consequence of this even and safe distribution of the lithium ions was an increased ability of the battery to produce larger currents. So much so, the team reports that the anode can handle currents five times that of conventional batteries. This raises the prospect of a battery that is not only safer and with greater energy density, but one that can be charged in possibly a fraction of the time.

“Building lithium metal anodes that are safe and have long lifetimes has been a scientific challenge for many decades,” Noh said. “The anodes we have developed overcome these hurdles and are an important, initial step toward commercial applications of lithium metal batteries.”

The research was published in the journal Nano Letters.

Source: Texas A&M

5 comments
notarichman
the article is interesting, but some important factors seem to have been left out;
how many recharge cycles will the batteries take? How long will the battery hold a charge? Is the battery easy and cheap to produce
in mass production? Are there size or voltage limitations determined by the design? i.e. can one battery replace a car battery? or can
a watch battery be made using the design?
Karmudjun
Excellent article. The technology takes something that we all understand and we all know how many charge cycles to expect, what the energy density should be (hopefully this new scaffolding will push the density even higher) and if all goes well, will allow an easy retooling for production. Which begs the question - how difficult will it be to scale this new technology to current battery manufacturing? What kind of precision manufacturing is required? Some technologies are so precise that the manufacturing process yields unacceptable product at too high a rate to make the production feasible. And what is the carbon footprint of this new scaffold production?

Nick, I like your writing style. You have given a lot of information in a succinct article, I won't need to find the journal to read the source material.

Most of us who read about lithium ion technologies know that the dendrite formation eventually causes the most reliable battery to fail. Since the technology increases the surface of the anode, the chemistry hasn't changed but the dendrite formation is greatly inhibited while the surface charge is increased allowing for greater current flow both ways, and greater safety. When will we see these exact same voltage lithium batteries with the much faster charging cycle and extended lifespan? I don't have a crystal ball so I can't fathom this battery being available anytime soon, but how I wish they were!
Eddy
With a current 100ah lithium car battery around 3.5 x an agm's price using even more lithium probably won't make them any more affordable in the near future for recreational users who are waiting to pounce on them when affordable for their highly desirable 50% weight difference and much higher DOD feature without causing a shorter life.
BlueOak
Lots of wishful talk but lacking any specifics whatsoever about actual performance. Yawn. Test it. Measure it. Prove it.
guzmanchinky
It's only a matter of time before we are charging up at Chevron in 5 minutes...