Sony develops bio battery that produces energy from paper waste
Sony has developed a bio battery that converts waste paper into glucose through an enzymatic process where the glucose is converted into electrical energy. The device, featured at the 2011 Eco-Products exhibition in Tokyo, could be used to charge mobile devices with paper waste that would otherwise end up sitting in a landfill.
To initiate the energy conversion process, users need only mix paper with a liquid mixture of enzymes and water that breaks down the paper into glucose. When mixed with oxygen, the newly formed glucose produces electrons and hydrogen ions that are transformed into energy. The process is similar to the way termites consume wood for energy. The technique yields water and acid gluconolactone as byproducts, which pose no threat to the environment. In fact, through all phases of usage, the battery provides an environmentally friendly energy source.
Using paper as an energy source is just the latest step in Sony’s bio battery R&D. The company has been steadily working on creating a self-sustaining energy source for the public since 2001. Researchers have focused on routine energy production methods in nature (photosynthesis, enzymatic reactions, kinetic energy), and aspired to translate them into novel methods of generating electricity.
The bio battery is constructed like a conventional battery. It is equipped with an anode, cathode, electrolyte and a separator. However, unlike standard batteries, the bio-battery utilizes biological enzymes as catalysts for the anode and cathode. Enzymes and electronic mediators are also equipped on the anode and cathode to help facilitate the transfer of electrons between enzymes and between enzymes and electrodes.
Energy production within the battery is initiated when glucose from the fuel source is broken down by the anode. The result produces protons and electrons.The protons are transferred to the cathode side through the separator and the electrons relocate via the mediator, and are then moved to the external circuit. These enzymes help initiate an oxygen-reduction process, which uses protons and electrons from the anode. The resulting reactions at the anode and cathode induce electrical energy by creating proton and electron flow in the cell system.
Although Sony is paving the way for making sustainable energy sources available to the public, it still has many obstacles to overcome before manifesting that reality. The level of energy that a bio battery is able to produce is relatively low. The latest battery generates about 18 mW of power, which is enough to power most personal audio devices on the market
A “passive-type” bio battery achieved a maximum power output of 50 mW during testing in 2007. This is a drastic increase over 18 mW but still a far cry from the amount of energy that is produced from disposable and rechargable batteries. A passive bio battery is slightly different from the bio battery recently unveiled by Sony; it is powered by a direct glucose injection rather than by a chemical reaction from mixing liquid and air.
Since 2007, Sony has been able to produce smaller battery units that are capable of producing sufficient energy for powering small consumer electronics. The company believes that the bio battery will become a viable next-generation power source as the demand for clean energy technologies increases. The long-term R&D goal for Sony is to enhance the battery’s performance so that it can power laptops and other mobile devices.