Epishine has developed a solar cell optimised for indoor use. The light energy harvesting (LEH) modules are optimised to convert light from indoor lighting into enough energy to power small electronic devices.
The LEH module is only 0.2mm thick, making it straightforward to fit into different devices without adding thickness to it. The module also fits on curved surfaces with a bending radius of 10mm.
The module can be connected more or less directly to the application for applications that only require to be powered when there is light, like an access card or a thermometer.
In applications where power is needed, even when there is no light available or if the momentary power required is more than the LEH module can deliver, an energy storage solution like a small super cap or rechargeable battery can be implemented. The LEH module charges the energy storage when light is available, and the storage solution power the application when needed.
Examples of applications built in this way are sensors that communicate wirelessly, including temperature and humidity sensors or fire detectors.
Its standard sizes of cells have an active area of 50mm by 20, 30 or 50mm.
Its LEH3 modules mainly comprise PET based on hydrocarbons and are non-toxic to the environment. It is usually the batteries that have the greatest Life Cycle Assessment (LCA) impact in this type of electronics. Most energy harvesting applications require a small energy storage as part of the power solution, but when you can change from a battery that stores energy for several years (with no energy harvesting) to something that stores some days of energy, the LCA calculation is significantly improved.