World’s Smallest Battery Can Power Computers the Size of a Grain of Dust
Researchers used the Swiss-roll process to enable on-chip batteries for dust-sized computers.
With computers getting smaller and smaller — from cellphones with the power of laptops to sensors small enough to be unobtrusive on the body — the question has long been how do we make batteries small enough to power them? A research team led by Chemnitz University of Technology recently presented a groundbreaking technology for submillimeter-scale energy storage techniques.
Previously, development for smart dust applications such as biocompatible sensors in the body has been hindered mainly by lack of on-chip power sources for operation anytime and anywhere and difficulties producing integrable micro-batteries. The Chemnitz researchers, led by Dr. Oliver G. Schmidt, published their findings in Advanced Energy Materials, proposing the world’s smallest battery as an application-oriented prototype.
Where mainstream micro-battery structures include stacked thin films on the chip or electrode pillars and on-chip interdigitated microelectrodes, this new micro-origami process is capable of winding stacked thin films into Swiss-roll structures. This arrangement reduces the footprint area, mimicking the structure of most successful full-sized cylinder batteries — and allowing for maintenance of adequate energy storage, in contrast to other techniques.
As for eventually integrating a dust-sized battery into a microsystem, the key is attainable energy. Since sub-millimeter devices can survive on nW power budgets, an integrable on-chip battery with attainable energy of 1 μWh can power the nW device for over a month. However, devices requiring frequent monitoring and data transmission increase power consumption by up to 100 μW, making micro-battery design more difficult.
Using the “Swiss-roll” or “micro-origami” technique, the research team has produced rechargeable micro-batteries that could power the world’s smallest computer chips for about ten hours. They continue to pursue greater capabilities for integration in dust-sized computers, but the battery shows great potential for a number of applications, including numerous IoT applications, miniaturized medical implants, microrobotic systems, and ultra-flexible electronics.