Research on the Calibration Method of Battery Internal Resistance Tester

This paper introduces innovative calibration methods for battery internal resistance testers, specifically targeting the two common calibration methods for such testers-AC injection and AC discharge methods. For the AC injection method, the calibration process and accuracy have been optimized by introducing senseless resistors, coaxial line design, and a high-precision voltage feedback adjustment system, enhancing the accuracy and reliability of the testing process. For the AC discharge method, a constant voltage source in series with a resistor is used to simulate a battery, providing a more convenient and controlled calibration method, while also offering more precise calibration results. The experimental results of this paper demonstrate that the calibration methods proposed can effectively carry out the calibration of battery internal resistance testers, with both AC injection and AC discharge testers achieving resistance and voltage measurement errors within ± 1%. Moreover, the voltage measurement error can be further limited to within 0.5%, showcasing the effectiveness of the new calibration techniques. These findings confirm the significant advantage of the advanced methods in improving calibration precision, providing a reliable technical foundation for assessing battery conditions. This innovation is crucial for ensuring the accuracy of battery internal resistance measurements, which is key to maintaining reliable power systems and optimizing battery performance.