• Embedded Battery Sensors
  • Battery Testers
  • Battery Monitors

Battery Monitoring Using Large Pulse Resistance™ (LPR) Technology


While LPR™ is an exemplary technique for battery diagnostics, it is truly unmatched as a technology for continuous monitoring. Because LPR is largely immune from the effects of connected electronics, the LPR technique can be applied continuously to determine the internal resistance of a battery while a battery is being used.

State of Charge

Internal resistance is directly related to battery state of charge.  As a battery is charged, its internal resistance decreases and as the battery is discharged, internal resistance rises. By precisely measuring internal resistance while a battery is being used, LPR can be used to directly indicate the state of charge, much like a gauge measures the level of fuel in a tank. 

Compared to a simple voltmeter LED method, LPR provides unparalelled accuracy and reliability regardless of loads or charging currents applied to the battery. 

State of Health

By comparing the internal resistance of the battery at every full charge, LPR can be used to track the change in total available capacity. Over time the change in 'full-charge' internal resistance, caused by sulfation, dehydration or many other decay factors, provides information about how battery capacity is decreasing over the life of the battery. This information can be used to predict when a battery is going to reach a critically low level of total capacity and needs to be replaced. 

State of health information is simply not available from available common monitoring methods such as voltmeters or current counting meters. 

The Battery Bug Deep Cycle Monitor (BB-DCM) series and Argus' Embedded Battery Sensors use LPR technology to provide battery 'fuel gauge' and state of health information. All BB-DCM models display battery life and battery charge level, and provide alarms to indicate when it is time to recharge or replace the battery. To learn about deep cycle and heavy duty battery monitors, look more closely at the BB-DCM series.

The Argus AA Series diagnostic testers models 350, 400 and 500P use LPR technology for capacity testing.

Argus LPR technology draws a large load current pulse from the battery for a very short period of time and simultaneously measures the voltage of the battery. Using Ohm’s law (V = I*R), the tester directly measures the DC internal resistance of the battery.

The internal resistance is correlated to a cold cranking amp (CCA) value for a particular battery and state of charge. As internal resistance increases, the battery's CCA decreases.