‘Transient electronics’ is an increasingly important route for R&D as one answer to the growing problem of disposing of unwanted electronic kit.
There is work going on to develop dissolving PCBs and now Iowa State University researchers have developed a dissolving battery.
It is a 5mm x 6mm x 1mm lithium-ion battery which delivers 2.5V and can power a laptop for 15 minutes.
It has an anode, cathode and an electrolyte separator within two layers of dissolvable polyvinyl alchol-based polymer.
In water, the battery’s polymer casing swells and the electrodes are broken apart, causing it to dissolve, except for some nanoparticles, in around half an hour.
“Unlike conventional electronics that are designed to last for extensive periods of time, a key and unique attribute of transient electronics is to operate over a typically short and well-defined period, and undergo fast and, ideally, complete self-deconstruction and vanish when transiency is triggered,” says the Iowa paper.
Although in-body dissolving batteries would be very useful to avoid invasive surgery to remove old or unwanted batteries implanted in the body, this battery’s use of lithium makes it unsuitable for that.