Energy

Solid-state magnesium-ion batteries could lick lithium

Solid-state magnesium-ion batt...
Researchers have developed a magnesium-based material that could allow for solid-state magnesium-ion batteries
Researchers have developed a magnesium-based material that could allow for solid-state magnesium-ion batteries
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Researchers have developed a magnesium-based material that could allow for solid-state magnesium-ion batteries
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Researchers have developed a magnesium-based material that could allow for solid-state magnesium-ion batteries
Researchers in the NMR lab, which helped prove experimentally that the new material was an effective conductor of magnesium ions
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Researchers in the NMR lab, which helped prove experimentally that the new material was an effective conductor of magnesium ions

Lithium-ion batteries are the undisputed top dog of the battery world at the moment, but magnesium-ion devices have the potential to steal the crown – if scientists can crack the problem of finding an efficient electrolyte. Now a collaboration between Berkeley Lab, MIT and Argonne National Laboratory has developed a solid-state material that appears to be one of the fastest conductors of magnesium-ions, which could lead to safer and more efficient batteries.

Lithium-based batteries power everything from phones to electric cars, and while the metal does the job for now, there's plenty of room for improvement in terms of efficiency and price. Magnesium, on the other hand, has a higher energy density than lithium and is far more abundant in the natural world, meaning devices made with the stuff should be cheaper and easier to produce.

The stumbling block to using magnesium in batteries is often the electrolyte, the material that carries the charge between the cathode and anode. Recent research from Toyota and KIT has focused on developing better liquid electrolytes, but these have the tendency to corrode other parts of the battery. So, the scientists on the new study wanted to try something else.

"Magnesium is such a new technology, it doesn't have any good liquid electrolytes," says Gerbrand Ceder, co-author of a paper describing the new device. "We thought, why not leapfrog and make a solid-state electrolyte?"

The end result of their work is a material called magnesium scandium selenide spinel, a solid-state electrolyte that allows magnesium ions to easily move through the material. In fact, the team found that their electrolyte was as effective a conductor as the solid-state electrolytes used in some lithium batteries.

Researchers in the NMR lab, which helped prove experimentally that the new material was an effective conductor of magnesium ions
Researchers in the NMR lab, which helped prove experimentally that the new material was an effective conductor of magnesium ions

Theoretical studies initially predicted that the material would work this well, and to confirm that practically the team ran nuclear magnetic resonance (NMR) spectroscopy experiments. This instrument can be tuned to detect magnesium or lithium ions moving through a material, but because the material the team had developed was so new and complex, they had some trouble interpreting the data.

"Protocols are basically non-existent," says Pieremanuele Canepa, lead author of the study. "These findings were only possible by combining a multi-technique approach (solid-state NMR and synchrotron measurements at Argonne) in addition to conventional electrochemical characterization."

As encouraging as the find is, the team says a few kinks need to be ironed out before the magnesium material could be used in an actual battery. Currently, there's a small amount of electron leakage, but the improved ion mobility is encouraging for an eventual commercial solid-state battery, which is much safer than the conventional liquid-based devices.

"This probably has a long way to go before you can make a battery out of it, but it's the first demonstration you can make solid-state materials with really good magnesium mobility through it," says Ceder. "Magnesium is thought to move slowly in most solids, so nobody thought this would be possible."

The research was published in the journal Nature Communications.

Source: Lawrence Berkeley National Laboratory

17 comments
MBoot
Just what the world needs! The more potential there is in the production new, clean energy sources the better - the clean-up is beginning thanks to the incredible work done by Tesla auto's.
JoelTaylor
Yet another new battery technology that we won't ever see again. >sigh< Remember 3D batteries? Sodium batteries? Lithium-Air? Aluminum-Graphite?
MerlinGuy
What do they think the readers never took a high school chemistry test? Magnesium? Really? They don't even mention that magnesium is highly flammable and very easy to ignite. Maybe they have a process or compound that inhibits combustion but I would assume they would mention that right up front. Someone should do a study of academic research to see what percentage is real and what percentage is just a way to pump government grant money in to wildly implausible research. And because of this I'm out.
blitherer
Magnesium and heat from charge/discharge, what could go wrong?
MarylandUSA
The road to better rechargeable batteries is littered with stories that read, "Researchers say..." about technologies that didn't pan out. Call me when you're ready to report, "Engineers have announced..." I can name only two new secondary-battery chemistries since lithium-ion that have made it to mass production: nickel-zinc (AA cells) and lithium-polymer.
NoelFrothingham
blitherer, hydrogen is also highly reactive in the presence of oxygen. When was the last (or even the first time) you heard about a simple glass of water spontaneously burst into flame or explode?
Craig Jennings
@Merlin Worried about the reactivity of magnesium? Opposed to what? Lithium? :D
mike_edward
This is great and all and I enjoy reading about 'new innovations' on this site, but realistically? Here we are, still using lithium batteries, the same old solar panel technology that is over thirty years old and on and on. I often have read and seen real, working innovations presented here over the years and on other sites, over a much longer time and still--no 'super batteries', no 'wonder solar panels' and the like. The truth is, the current industries are not going to reinvent their own wheel. Realistically these product innovations won't ever come to light any time soon.
Graeme S
And therein is the main problem, as Mike alluded to, getting new technology into mass production. The problem is not the scientists, I applaud their efforts, along the lines of "go where no-one has gone before", but then it all comes to a screaming stop because companies, having invested billions of dollars into factories and infrastructure to produce an item that would be obsolete by the new technology have to consider their futures. Advances, sad to say, are at the mercy of the bean counters. Getting new beneficial technology past the bean counters is a hard job, getting it past the existing businesses just as hard. Entrepreneurs .... where are you?
JimFox
It is your 'duty' to report these "breakthroughs but I have to agree with the consensus- we are sick of hearing dozens of such stuff that invariably turns out to be bunkum. AS for comment on flammability of magnesium- this is NOT magnesium, but a material called magnesium scandium selenide spinel. And not prone to busting into flame. If people would read instead of displaying their inability to do so ...