Evaluation of State of Charge Meters for BA-5800 Lithium Sulfur Dioxide Batteries

摘要

Product Manager Global Positioning System (PM GPS) sponsored the test andevaluation of BA-5800/U (a military lithium sulfur dioxide battery) State of Charge (SOC) meters made by two manufacturers, Monica Computers and Quality Power Supplies, Limited. This battery is used to power the AN/PSN-11 Precision Lightweight GPS Receiver (PLGR). Over 70,000 PLGR's have been distributed to the Army by PM GPS with a grand total of 78,800 to be distributed by September 1998. Battery operating costs are the major life cycle cost to the PLGR, and there are no SOC testers for this battery in the Army inventory. Based on field data collected from PLGR users at Fort Drum, NY, an economic analysis concluded that the use of the SOC meter saves 43.9% in the cost of batteries, and the use of 228 SOC meters in active Army units would save $4,270,000 over a 5-year period. Through controlled laboratory testing, it was concluded that the SOC meters from both manufacturers provide a reading accurate to within 10% of actual battery capacity at room temperature and above. At the minimum meter operating temperature of zero degrees Celsius, both meters have greater error and conservatively underestimate the capacity of the battery.