A new 'redox flow' battery could help to power lasers and solar panels.
Anyone that's ever had the pleasure of a laptop overheating on their thighs knows that computers can get hot. Keeping chip stacks within a workable temperature has always been a challenge when designing powerful machines – now researchers have come up with a system that uses liquid fuel to simultaneously power and cool components.
Scientists at ETH Zurich and IBM Research Zurich have developed a miniature “redox flow” battery, which both provides enough energy to power the chip while simultaneously dissipating the heat it produces. It does this with the use of two liquid electrolytes, pumped into the battery across a 3D-printed micro-channel.
Flow batteries already exist, but tend to be used on a large scale to store energy. Recent breakthroughs in this area have seen Harvard researchers develop ways of storing energy generated from wind and solar sources, able to last for over ten years. The scale of these systems, however, had prevented researchers from merging power with heat dissipation – until now.
"We are the first scientists to build such a small flow battery so as to combine energy supply and cooling," says Julian Marschewski, a doctoral student at ETH Zurich.
The main challenge facing the researchers was coming up with a means to supply electrolytes to the batteries, whilst keeping the energy needed to pump these chemicals to a minimum. In the end, they settled on a pair of wedge-shaped, 3D-printed polymer channels, designed to press the liquids through a porous electrode layer. The system can generate 1.4 watts per square centimeter, with only 0.4 watt taken to power the pump, leaving one watt for the battery.
Because the electrolytes dissipate more heat than the battery generates, they're able to cool the chip.
While the results are impressive as an initial proof-of-concept, the scientists must now scale the electricity generation so that it can effectively power a computer chip. If they pull this off, the redox flow battery could have a range of applications – from storing solar energy without the need of external power supplies, to creating better batteries for powering (and cooling) lasers.