Browse Publications Technical Papers 2003-01-0099

Automotive “Smart” Battery with State of Health Conductance Testing and Monitoring Technology (onGUARD®) 2003-01-0099

This paper will detail the development and validation of the world's first integrated smart automotive lead-acid battery tester. As today's automobiles add more electronic and electrical systems to the vehicle the need for reliable battery power is more important than ever. The need to determine the battery's functional life span has demanded a product to reliably test the battery's state of health (SOH).
After two years of development backed up by over 17 years experience in testing lead acid batteries, onGUARD™ delivers the ability to accurately test and predict the batteries life expectancy.
The paper details the elements behind the smart tester technology and its ability to measure the battery's voltage, temperature and conductance to accurately diagnose the health of the battery. A background of conductance testing technology and its approach to measuring the health of a battery by measuring the internal resistance of the battery is included. The benefits of conductance as a safe and accurate alternative to load testing in determining the Cold Cranking Amps of a battery are included.
The mechanical configuration of onGUARD will be described, as it presently is available in two platforms. One platform is fully integrated into the battery, designed for a specific manufacturer's battery. A second is an external sensor module, which can be, applied to any lead acid battery in the 300 to 1500 CCA range. The integrated onGUARD model is designed to fit inside a battery lid connected internally to the battery's posts. The onGUARD unit can be programmed to specifically test a particular battery after a battery characterization has been established, and this process will be explained. The aftermarket onGUARD unit is a universal model to be attached to the outside case of the battery. The customer interface process of pushing and holding a pushbutton on the onGUARD unit perform measurements, and a display of test results as shown by a simple series of LEDs (A pattern of green, yellow and red LEDs indicate the batteries state of health) will be included.
A full-production lead-acid SLI automotive battery will launch in October 2002 in Japan featuring an integrated onGUARD conductance test module with SOH and voltage state of charge (SOC) diagnostics. This paper provides some technical details of that platform, and as onGUARD has application in automotive, marine and battery backup power systems, a brief mention of potential benefits from the integration of additional technologies is also presented.


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