Georgia Institute of Technology researchers have developed a self-charging power cell that uses a piezoelectric membrane to convert mechanical energy to chemical energy, then stores that energy until it can be released as en electrical current. Combining the power generator with the energy storage device, this hybrid is claimed to be more efficient than systems with separate generators and batteries. When the piezoelectric membrane is flexed, it moves lithium ions in the power cell from one side of the cell to the other. Membranes in shoe heels and soles could produce power when a person walked, powering small electronic devices such as calculators or cell phones. Zhong Lin Wang, a Regents professor in the School of Materials Science and Engineering Georgia Tech, explains the distinguishing feature of his team’s innovation. “People are accustomed to considering electrical generation and storage as two separate operations done in two separate units. We have put them together in a single hybrid unit to create a …
Nano to Macro – Piezoelectrics Have Power
Two far-flung enterprises are using piezoelectric devices to generate answers to widely disparate questions. The first set of questions is intensely personal. “Can a heart implanted micro robot operate permanently? “Can cell phones and tiny robots implanted in the heart operate permanently without having their batteries charged? These provocative questions highlight a web page from KAIST, the Korea Advanced Institute of Science and Technology, which focuses on the Institute’s work with piezoelectric devices. Such devices can tranform vibrations, pressure, and other mechanical forces into an electric current. Older “hi-fi” systems used piezoelectric cartridges in their LP-playing tone arms to transduce the vibrations from a needle touching the record’s grooves into signals to the system’s amplifier. Dr. Zhong Lin Wang explains, “Our FAND (Flexible and Nano-bio-energy Device Lab) group has developed new forms of highly efficient flexible nanogenerator technology using freely bendable piezoelectric ceramic thin film nano-materials and nanocomposite materials that can convert the tiny movements of human body (such as …