Thin and flexible printed energy storage devices that complement many of the large area printed electronics developments today, have been a growing necessity in the last few years. Energy harvesting and consumption have been in place for some time, but a suitable, printed rechargeable store of energy is lacking. Supercapacitors have been presented as a possible solution, and are indeed suitable for a limited number of applications, but suffer from short energy retention times due to leakage currents and low energy densities. A few printed batteries, based on zinc chemistry are present, but are non-rechargeable and designed for single use.
We have recently developed a printable zinc based chemistry which is rechargeable. The objective of the Flexible Printed Energy Storage (FlexEn) project is to formulate these newly developed electrodes into pastes which are suitable for screen printing and demonstrate the viability of screen printing to produce rechargeable batteries which can be easily integrated with other printed devices.