If spy agencies want to make self-destructing gadgets that leave no trace, their every component should be able to go kaput, including their batteries. Various research teams have been trying develop transient batteries for a while now, but according to a group of scientists from Iowa State University, their creation is the first one that's able to "demonstrate the power, stability and shelf life for practical use." The team's self-destruction lithium-ion battery can power a calculator for 15 minutes and dissolve in water within half an hour.
The one-millimeter-thick and five-millimeter-long device uses typical lithium-ion technology. Unlike typical batteries though, it's encased in degradable polymer composite that swells and eventually breaks apart in water. While promising, it will probably take some time before the team can make a version that can power more sophisticated electronics. They still have to figure out how to scale up a battery that has multiple layers and has such a complex structure.