Group of researchers of university of Illinois, having combined methods of 3D-holographic lithograph and a usual two-dimensional photolithography, created the microscopic, but highly effective battery. Tiny dimensions of the created battery will allow to integrate it directly on chips of microelectronic devices, doing these chips absolutely independent of external sources of electric energy.
“Our the 3D – the microbattery possesses exclusive electric characteristics, and the production technology of such batteries can be scaled to any sizes thanks to what such batteries can be used in the most wide range of areas” – Paul Brown, professor of materials science from university of Illinois tells, – “In most cases microelectronic devices work due to the energy delivered from the outside of their chips and it is connected with difficulty of miniaturization of technologies of accumulation of energy. The tiny, capacious and effective battery which is built in directly the chip can solve the mass of design problems when developing wireless sensors, low-power send-receive devices, monitors, the portable and implanted medical electronics”.
Creating the battery, scientists used technology of 3D-holographic lithograph for creation of difficult internal structure of electrodes, and by means of a two-dimensional photolithography electrodes were given the necessary external form. In this work all latest achievements of technologies of development, modeling and production which set allowed to receive the high capacity and a high rate of density of storage of energy were used.
In technology of 3D-holographic lithograph some beams of lasers which are focused in certain points of photosensitive material are used, creating in volume of material microscopic structures practically of any complexity. After such processing the remains of the beam of the laser of material which did not get under influence are washed away by special solvent, leaving the structure consisting of solid polymeric material on which surface besiege conducting material, turning all this into a battery electrode with rather big area.
Bolshaya Square of an electrode and its porous structure provides fast transfer of electric charges by means of electrons and ions, approaching high-speed indicators of such batteries to values of similar indicators of supercondensers. Besides, carefully designed features of a lattice of an electrode prevent process of accumulation and fixing of ions of lithium near one of electrodes that increases reliability of its work, i.e. quantity of cycles of a charge category, many times over in comparison with the batteries having usual graphite electrodes.
Prototypes new 3D – microbatteries which thickness makes about 10 microns, and the area – 4 square millimeters, were capable to give out 500 mk of current, supporting a luminescence of a usual light-emitting diode for 600 seconds of time. And after 200 cycles of a charge discharge the general capacity of the battery decreased by only 12 percent.
“We developed such method of production of three-dimensional lities – ion batteries which completely we will combine with the existing production technologies of semiconductor chips” – tells Heylong Ning (Hailong Ning), one of scientists, – “And now without special difficulties it will be possible to make specialized chips which will be able to provide themselves with the energy necessary to them for long work”.