FLEET MAINTENANCE
SoC YOUR BATTERY
{
State of Charge
}
H
ere at Clore Automotive, we get a lot of questions related to battery and system testing. How to handle different battery types… how to properly load test a battery… what the impact of extreme temperatures can be on battery testing… and more. One big question we get is related to how battery State of Charge (SoC) impacts battery testing and how the different testing methodologies handle state of charge issues differently. It Is important for technicians, roadside assist crews and DIYers to know the impact SoC can have on battery testing results. First, what do we mean by state of charge? This refers to how fully charged a given battery is, on a scale from 0% (stone cold dead) to 100% (fully charged). Primarily, this value is driven by the Open Circuit Voltage (OCV) of the battery, where ~12.8V
18
Tow Professional | Volume 10 • Issue 3
|
www.towprofessional.com
typically is equivalent to a fully charged 12V (nominal) vehicle starting battery. So, how could the state of charge impact a battery test? Depending on the test method used, the answer is, SoC can have a dramatic impact on testing accuracy. For the purpose of this article, we’ll focus on two testing methods: Invasive Load Testing and Digital Testing. Invasive Load Testing refers to testing methods and equipment that place a specific load on the battery for a specific period of time. Examples of invasive load testers include fixed load testers (the proverbial cheese grater, such as our Model 1852) and variable load testers (carbon pile testers, such as our Model 1876). Digital Testing refers to electronic testers that may or may not place a load on the battery (hint: SOLAR BA series testers do) and send an electronic signal through
