Miniature solar cells can significantly extend the operating life between battery charging cycles of speed and distance monitors for runners and cyclists, digital cameras, laptops, portable media players, pocket PCs and outdoor products. In the coming year, after the successful launch of the first LROGC02 type panel, Sharp plans to expand the product family of solar components for mobile applications to five models to address the broad range of mobile applications. What they all have in common is the high efficiency of 13 percent and the low mounting depth of only 0.8 millimetres, which makes for extreme ease of integration into the body of devices. A further distinguishing characteristic of Sharp solar panels is that cells are double wired to ensure panel performance is fully maintained even in the event of a cell breakage. This is an important feature especially for use in portable devices, which are subject to high mechanical stress e.g. if they are dropped.
By varying the number and configuration of the individual polycrystalline solar cells the panels provide different power outputs and voltages. The range extends from single cell types with a 30 mW power output at a voltage of 0.5 V to models with 10 cells and a power output of 300 mW at 5 V.
The first step towards expanding the portfolio will be the launch of the LROGC03 type panel in the first quarter of 2010. With a surface of 41 x 33 millimetres, this member of the product family is approximately half the size of the first LROGC02 type panel and reaches a maximum power output of 130 mW with a voltage of 5 V with its 10 cells. This makes them particularly suitable for so-called Smart Meter, small portable consumer devices such as mp3 players as well as intelligent car keys that report, for example, if windows and doors are properly closed or how much petrol is left in the tank.
In the long term, Sharp is also working on redesigning the solar panel components. Relocating the wiring to the underside of the panel will give next-generation models an even, continuous surface. This will increase efficiency to as much as 20 percent as the cells will no longer be shaded by the wires. But the device’s design will also benefit if the exterior is no longer criss-crossed by visible conductors.
Samples of the LR0GC03 type solar panels will be available from European Sharp Microelectronics distributors and its distribution partners from Q1/2010 onwards.