As a key component of the power system, batteries must be tested and maintained annually, quarterly or even monthly and their test data needs to be analyzed on a regular basis.
Practice has proved that there is no correlation between voltage and capacity, because the voltage only reflects the surface parameters of the battery.

Internationally, tests for conductance or internal resistance have been widely used in the routine maintenance of batteries to replace the previous voltage check method. Because the conductance or internal resistance is a parameter that reflects the internals of the battery, the conductance or internal resistance of the battery has been recognized as an important parameter for accurately and quickly determining the health of the battery.
The battery conductance or internal resistance tester is a digital storage type multifunctional portable test instrument that quickly and accurately measures the operating state of the battery. Through on-line testing, the meter can display and record multiple battery important parameters such as battery voltage, conductance or internal resistance, and connecting strip resistance, accurately and effectively determine the battery's excellent condition, and can be combined with computer and dedicated battery data analysis software to form intelligent test. The device further tracks the decay trend of the battery and alarms in advance to facilitate engineering and management personnel to handle the discretion.?