Researchers at the University of Illinois at Urbana-Champaign (UI) have announced their new Microbatteries that out-power even the best supercapacitors and could drive new applications in radio communications and compact electronics.
The graphic illustrates a high power battery technology from the University of Illinois. Ions flow between three-dimensional micro-electrodes in a lithium ion battery. Image Credit: Beckman Institute for Advanced Science and Technology at the University of Illinois.
The press release suggests the new microbattery is the most powerful battery on the planet. They are only a few millimeters in size and yet they pack such a punch that a driver could use a cellphone powered by these batteries to jump-start a dead car battery – and then recharge the phone in “the blink of an eye”. This is a big claim.
Led by William P. King, the UI Bliss Professor of mechanical science and engineering, the researchers published their results in the April 16 issue of Nature Communications. The paper is of course peer reviewed and the hard details state the lithium ion microbatteries have power densities up to 7.4 mWcm−2 μm−1, which equals or exceeds that of the best supercapacitors, and which is 2,000 times higher than that of other microbatteries.
This looks serious . . .
Professor King said, “This is a whole new way to think about batteries. A battery can deliver far more power than anybody ever thought. In recent decades, electronics have gotten small. The thinking parts of computers have gotten small. And the battery has lagged far behind. This is a microtechnology that could change all of that. Now the power source is as high-performance as the rest of it.”
The team’s key insight is that the battery microarchitecture can concurrently optimize ion and electron transport for high-power delivery, realized here as a ‘three-dimensional bicontinuous interdigitated’ microelectrodes. The battery microarchitecture affords trade-offs between power and energy density that result in a high-performance power source, and which is scalable to larger areas.
3D Battery Image From the Study Abstract.
With currently available power sources, users have had to choose between power and energy. For applications that need a lot of power, like broadcasting a radio signal over a long distance, capacitors can release energy very quickly but can only store a small amount. For applications that need a lot of energy, like playing a radio for a long time, fuel cells and batteries can hold a lot of energy but release it or recharge slowly.
James Pikul, a graduate student and first author of the paper said, “There’s a sacrifice, if you want high energy you can’t get high power; if you want high power it’s very difficult to get high energy. But for very interesting applications, especially modern applications, you really need both. That’s what our batteries are starting to do. We’re really pushing into an area in the energy storage design space that is not currently available with technologies today.”
The new microbatteries offer both power and energy, and by tweaking the structure a bit, the researchers can tune them over a wide range on the power-versus-energy scale.
Related article: How Long Should a Lithium Ion Battery Survive in an EV?
The new microbatteries owe their high performance to their internal three-dimensional microstructure. Batteries have two key components: the anode (minus side) and cathode (plus side). Building on a novel fast-charging cathode design by materials science and engineering professor Paul Braun’s group, King and Pikul developed a matching anode and then developed a new way to integrate the two components at the microscale to make a complete battery with superior performance.
With so much power, the batteries could enable sensors or radio signals that broadcast 30 times farther, or the devices might be 30 times smaller. The batteries are rechargeable and can charge 1,000 times faster than competing technologies, “Imagine juicing up a credit-card-thin phone in less than a second,” quotes the press release. In addition to consumer electronics, medical devices, lasers, sensors and other applications could see leaps forward in technology with such power sources available.
King said quite correctly, “Any kind of electronic device is limited by the size of the battery – until now. Consider personal medical devices and implants, where the battery is an enormous brick, and it’s connected to itty-bitty electronics and tiny wires. Now the battery is also tiny.”
The team’s plan for the future is working on integrating their batteries with other electronics components, as well as manufacturability at low cost.
Pikul said, “Now we can think outside of the box. It’s a new enabling technology. It’s not a progressive improvement over previous technologies; it breaks the normal paradigms of energy sources. It’s allowing us to do different, new things.”
Professor King is no lightweight looking to make a mark. He’s also affiliated with the Beckman Institute for Advanced Science and Technology; the Frederick Seitz Materials Research Laboratory; the Micro and Nanotechnology Laboratory; as well as the department of electrical and computer engineering at the University of Illinois.
Details are still really thin. The energy and power density numbers aren’t out nor the all important charge discharge cycle life. The first hurdle, costs, aren’t covered either. Much more to come we hope.
For those folks in the battery business, the study paper is worth a look. For the rest of us, the paywall is in place even though a U.S. government department, the Air Force Office of Scientific Research helped fund the work that is supposed to make these kinds of things publicly available.
On the other hand a paltry $32 will buy a copy so the tech won’t stay in the U.S. for even a day – its likely swiped already. C’est la vie.
By. Brian Westenhaus