On June 26th 1993, the U.S. Air Force launched the 24th Navstar satellite into orbit; this completed a network of 24 satellites now known as the Global Positioning System (GPS). These satellites act as reference points to calculate positions anywhere on the planet to a matter of meters. In it infancy, this information was only accessible by the military or large organisations; however, as technology has developed, GPS receivers have been miniaturised and their cost reduced making this technology accessible to almost everybody.

Nowadays GPS is becoming commonplace used in many applications from cars, boats, planes, construction/survey equipment and even laptop computers. As this technology develops, GPS will become as common as a mobile telephone becoming a universal utility.

GPS receivers come in a wide range of shapes and sizes from small pocket sized hand-held devices to compact flash receivers used in laptop computers and PC’s. Many of these devices however need to be mobile, reliable and work in remote areas likely under extreme conditions. Because of this, the battery packs used to power such devices must be able to cope with all of these demands.

Many of the basic handheld GPS devices commonly used by walkers, hikers and sailors run off standard AA NiMh rechargeable cells. Some of the more advanced receivers such as Chartplotters, Automotive Trackers and PDA’s make use of more specialised rechargeable Lithium Ion batteries.

Sonnenschein Lithium Gmbh offer a wide range of lithium thionyl chloride cells and battery packs and have been chosen by many designers and have been the source of long term power in a number of different GPS applications.