The Design Of Battery Performance And Residual Capacity Tester

VRLAB as an energy storage device is widely used in all areas of automotive, communications, electronics, and mobile phones. With the growth of use, battery performance requirements are highly increasing, in order to understanding its performance, which requires corresponding detection devices. This paper analyzes the main parameters of the battery internal resistance and capacity during the testing process of difficulties and complexity. This paper adopts DC-AC Reform to test resistance and constant current discharge to test capacity. The residual capacity is related to many factors and has lots of difficulties in testing it, so the prediction of residual battery method has been the current hot issue in the field of battery industry. Through the comparative analysis of commonly methods used in the estimation, this paper adopts short time large current discharge load voltage method referred to as the constant discharge-voltage estimation method to estimate SOC.The design of battery tester based on STM32 MCU to build hardware system and write software drivers. Using the LM358 AMP and MOSFET IRF540 constructing constant discharge circuit to achieve constant current discharge of the battery, besides, adding PI regulator to adjust the current stability. In order to realize little weak signal amplification adopt AD620 amplifier, using DHT11 sensor to sense the environment temperature, using CH340 G to realize USB to serial. By calling STM32 firmware library function to develop MCU program, write PC software using C# language. Hardware and software work together to realize battery tester function and complete the detection of 12 V lead-acid batteries.Finally, functional tests show that constant current load can achieve battery constant current discharge, residual capacity estimation and performance parameters value detected within allowable deviation, the tester can realize the communication with pc. Testing instrument can be used as reference tool of battery manufacturers and personnel repair battery, the design has good practicability and application prospects.