Research On Key Technology In Testbenches Of Lithium Battery Protection System

Lithium batteries as a new energy have been widely used in industrial and military applications. The lithiumalso uses a lithium battery protection board to protect lithium from overcharging, discharging and over current. Inorder to ensure the lithium battery protection board has played a protective role, it requires the testbenches oflithium battery protection system detecting it. The testbenches of lithium battery protection system is a testingdevice which measuring the parameters of the lithium battery protection board, whose functions include testingovercharge protection voltage, over-discharge protection voltage, over-current protection values, and otherimportant properties. However, most of the existing testbenches of lithium battery protection system is based onMCU and also makes the real lithium or expensive electronic load as testing power. This testbenches of lithiumbattery protection system have the following deficiencies. Firstly, a small number of test content and sections canbe tested. Secondly, it costs long test period. Thirdly, it is unfriend to communicate human and machine.In response to these deficiencies, this thesis proposes a testbenches of lithium battery protection system withhigh accuracy and simple circuit. The device is mainly composed of the hardware system design and softwaresystem design. The hardware system design as follows: Firstly, the embedded microprocessor S3C2440A is thecore of the main controller hardware platform of testbenches of lithium battery protection system. Its peripheralsinclude TFT display, touch screen, Nand Flash and nor Flash, etc. Secondly, the battery simulator was designedmainly by STM32which achieves high precision adjustable output voltage via the communication module, thevoltage generating module and the sample module. Thirdly, the constant current source controls high-power MOStube by voltage control module and the sampling module. The software system design as follows: Firstly, theWinCE6.0operating system customization and transplantation is completed. And the application software oftestbenches of lithium battery protection system is designed by WinCE6.0. Secondly, it designs an efficientcustom communication protocol coordinate data communication between each module with the RS-485standard.Finally, on the basis of hardware and software design, the device is used measuring the four series lithiumbattery protection board. And the results show that the device can measure9parameters of lithium batteryprotection board, including overcharge protection voltage and over-discharge protection voltage etc. It costs90sthat completes the test. And the absolute maximum voltage parameter error is6mV. The maximum relative errorof current parameters is3.3%.