New microbatteries are a real boost for electronics
17 April 2013
They may be just a few millimeters in size, but a mobile phone powered by one of these batteries would be able to revive a dead car battery.
Ions flow between three-dimensional micro-electrodes in a lithium ion battery (image courtesy of the Beckman Institute for Advanced Science and Technology)
Developed by researchers at the University of Illinois at Urbana-Champaign, the new microbatteries out-perform even the best supercapacitors and could drive new applications in radio communications and compact electronics. The research was led by Professor William King.
“This is a whole new way to think about batteries,” he said. “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.”
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.
“There’s a sacrifice,” said James Pikul, a graduate student and member of the research team. “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.
The batteries owe their high performance to their internal three-dimensional microstructure. Building on a novel fast-charging cathode design by Professor Paul Braun’s group at the university, 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 devices 30 times smaller. The batteries are rechargeable and can charge 1,000 times faster than competing technologies (a mobile phone battery in less than a second, claim the researchers).
The researchers are now working on integrating their batteries with other electronics components, as well as manufacturability at low cost.