A Method of Automatically Testing the Cell Voltage and Internal Resistance

The voltage and internal resistance of lithium-ion battery are two important battery parameters. Accurate and rapid characterization of these two parameters is the key to monitor the battery production stability and battery status, and improve the efficiency of production and testing.Scenscenarios to test the voltage and internal resistance of the cell include:

Fast, accurate and low-cost test of cell voltage and internal resistance, can help cell enterprises to accelerate the research and development and production rate.This paper uses a device RO1100 to automatically test cell voltage and internal resistance, which has high integration, high openness, perfect system function, maximum human intervention, and rapid realization of battery voltage internal resistance measurement.

Figure 1.Voltage internal resistance test: schematic diagram of traditional methods and automatic methods

Table 1.Comparison Between Traditional Methods and Automated Methods

Test Result

The voltage internal resistance repetition test of the four small soft pack lithium ion cells was conducted 100 times, and the total test time was less than 7min. According to the test results, the internal resistance C OV was less than 0.5%, and the voltage COV was less than 0.01%, indicating that the repeatability is very good, and can help the tester to quickly and stably assess the state of the cell at that time.

Figure 2. Voltage internal resistance test results of the four cells