Self Charging Battery Developed

The new Self-Charging Power Cell
Researchers from the Georgia Institute of Technology developed a unique power cell that self-charges directly by converting mechanical energy into chemical energy, storing the power until it is released as electrical current. This technology eliminates the need to convert mechanical energy into electrical energy increasing the efficiency of the system.
The new power cell is based on a special piezoelectric membrane that moves lithium ions from one side of the cell to the other when the membrane is subjected to a mechanical force. By driving the lithium ions through the polarized membrane using the piezoelectric potential the researchers were able to store chemical energy directly using an electrochemical process.
If located inside a shoe, the new power cell can store the energy created from normal human walking to help power small electronic devices. Soldiers of the future might be able to charge their equipment using power cell technology only by walking or running as they normally do.
According to professor Zhong Lin Wang form the School of Materials Science and Engineering at the Georgia Institute of Technology: " 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 self-charging power cell, demonstrating a new technique for charge conversion and storage in one integrated unit".
So far and after building and testing about 500 different units, the power cells can store about 0.036 milliamp-hours of power. The my issue still confronting Zhong Lin Wang and his team is that much of the mechanical energy applied to the cells is consumed by the process of deforming the stainless steel case of the power cell. Using an improved case might help in this respect and boost the power levels of the power cell.
Directly converting mechanical energy into chemical energy will not only increase the overall efficiency of creating and storing energy but  might also reduce the weight and space currently required by separate generators and batteries.
The power cell technology of the future could create and store power using mechanical energy from walking, car tires hitting the pavement, or even mechanical vibrations and ocean waves.
More information on the new power cell can be found on the Georgia Institute of Technology website.