The near future promises to bring us books that will be filled with digital paper, which will display the text of any book we wish to read. These books, printed with electronic ink, will be able to alternate between many texts at the push of a button. Within the ink printed on these digital pages will be tiny microprocessors and circuits that perform various functions. Also embedded in this ink will be the components of tiny, paper-thin batteries called Power Paper.
Power Paper will work exactly like a traditional battery, but it will be nearly as thin as a piece of paper. A Power Paper cell can generate 1.5 volts of electricity, which is about the same output as a watch or calculator battery. A Power Paper cell will be 0.5 millimeters thick, and several cells can be used in combination to provide more power. Here's how the Power Paper cell will work:
- A zinc and manganese dioxide (MnO2) -based cathode and anode are fabricated from proprietary inks. In a battery, the cathode refers to the positive terminal and the anode refers to the negative terminal.
- Standard silkscreen printing presses are used to print the batteries onto paper and other substrates.
- Power Paper batteries are integrated into production and assembly processes of thin electronic devices.
Power Paper batteries are printed directly onto thin substrates, such as paper, so they are far more flexible than any other battery. Because ink is used to produce Power Paper, the batteries are considered dry, and don't need the metal casing that conventional batteries do to contain harmful, toxic chemicals. This lack of casing allows electronics manufacturers to utilize the power source in many shapes and sizes. Since it doesn't require special production equipment, Power Paper can be made outside of clean- or dry-room conditions, which lowers production costs. Power Paper batteries can be produced for a mere 1 cent per square inch.