Chances are, there are a couple places your smartphone might be, either in your pocket or purse, or on your desk.
Today’s smartphones are more power-hungry than ever, and our desire for connectivity is energy-intensive. At home or at the office, you’re more likely to have your smartphone in a charging dock to keep it juiced up, but what about on the run? As some of today’s smartphones barely last four hours away from the grid, battery and charging technology seems to have some catchup to make.
A new nanogenerator could solve the smartphone battery life problem by harvesting the natural vibrations we make when we’re walking. When we move about, even just walking, nothing strenuous, we give off energy in various forms. Thermoelectric generators could harvest waste heat energy from the skin, and piezoelectric generators could harvest some types of movement. A new nanogenerator material, developed by a team of researchers from the University of Minnesota at Duluth (UMD) and Sun Yat-sen University (SYU), in China, could harvest the smallest movement, just vibrations.
The new material, jointly developed between UMD and SYU, takes advantage of a common piezoelectric material, polyvinylidene fluoride (PVDF), but with a designed imperfection. Normally, PVDF reacts to mechanical strain by generating an electric charge. By incorporating mesopores, tiny pores left by the removal of zinc oxide nanoparticles, the resulting PVDF sheet ends up being more sponge-like and flexible. Two electrode layers applied to this new porous PVDF makes a thinfilm nanogenerator that responds to vibrations, generating an electric current. The weight of a smartphone is more than enough to amplify the vibrations, making for a self-charging mobile electronic device. Instead of being made as a separate component, such a nanogenerator could simply be made as part of the device.