Design and Implementation of Lithium-ion Power Lithium-ion Battery Pack Monitoring System

Design and Implementation of Li-ion Power Lithium-ion Battery Pack Monitoring System 1 Analysis Battery is a power source that outputs electrical energy through discharge, and absorbs and recovers electrical energy through charging. The low-voltage power supply packaged by lithium-ion power lithium-ion batteries is the key equipment of the underwater robot system. Improper maintenance of the lithium battery will directly affect the efficiency and life of the lithium battery, and even directly damage the lithium battery, thereby affecting the overall function of the underwater robot, and in severe cases, it will also cause the robot's safety accident. Through online measurement of the parameters of the lithium-ion power lithium-ion battery pack, the operating status, operating characteristics and maintenance requirements of the lithium battery can be known in time. Therefore, research and development of lithium-ion power lithium-ion battery online monitoring system is imperative. In order to end the monitoring of lithium-ion power lithium-ion battery parameters, the demand planning parameter acquisition module is the first choice. Collect the voltage, current, temperature and other parameters of the lithium-ion power lithium-ion battery, upload them to the MCU with A/D conversion module, and record and refresh these data. 2. Overview of lithium-ion power lithium-ion battery pack monitoring system This system selects lax data acquisition and convergence data processing, respectively plans the voltage acquisition circuit, current acquisition circuit, and temperature acquisition circuit, and then transmits the data to the single-chip microcomputer for convergence processing. The architecture diagram is shown in Figure 2-1. This system monitoring strategy is the national 863 project underwater robot system lithium-ion power lithium-ion battery pack, using the ts-lfp160aha lithium-ion power lithium-ion battery manufactured by Shenzhen Lotte Technology. The battery pack consists of 8 batteries. Monitor the terminal voltage of each single battery to distinguish between overvoltage and undervoltage. Multi-point temperature measurement is required to monitor the temperature of each battery and the temperature and humidity of the battery pack address environment. 8 single cells are connected in series, and overcurrent can be judged by measuring the current in series. This text chooses TMS320LF2407A chip. The use of this chip as the CPU of the battery monitoring system is also reflected in the following aspects: 1. Energy saving, energy saving has become a hot issue in the planning of modern electronic equipment. When the device is powered by a secondary battery, the energy saving problem becomes more prominent and important. The DSP used in this method is powered by a 3.3v power supply, which reduces the loss of the controller. The chip power processing includes a low-power mode, which can enter the low-power mode independently of peripheral devices. 2. 16-channel input A/D converter. This makes sense with regard to multiplexed sub-circuits. It can directly connect the output of the acquisition circuit to the A/D conversion channel of the DSP. Instead of setting up an A/D conversion circuit outside the DSP. 3.40 input/output pins, which can be individually programmed or reused. It can be used to control peripheral circuits such as safety switches. 4. Serial communication interface (SCI) and 16-bit serial peripheral interface module (SPI) can be connected to the flash part of the monitoring system. 3. System hardware planning The hardware planning of the system mainly includes voltage acquisition circuit, current acquisition circuit and temperature acquisition circuit. The acquisition circuit uses TMS320LF2407A as the CPU. TMS320LF2407A is a high-function fixed-point 16-bit DSP device specially designed for real-time control by TI. The instruction cycle is 33ns. The front-end sampling A/D converter and the back-end PWM output hardware are integrated, which simplifies the hardware circuit planning and meets the real-time requirements of the system. 3.1 Voltage acquisition circuit planning This method uses lithium-ion power lithium-ion batteries as a processing strategy. The battery pack consists of 8 3.6v lithium batteries. The rated voltage of each battery is 3.6v, and the terminal voltage is 4.25v. The voltage acquisition accuracy is required to be within 1.5%. The minimum sampling frequency required by the battery processing system is 20ms. The system uses a linear optocoupler as a signal transmission sampling device to collect and block data from the data acquisition system, thereby blocking the voltage of each battery in the front end. The large voltage of the battery must be scaled down to reflect that the change in the voltage value of the battery is faithful to the DSP. After this, it needs to be multiplexed into the microprocessor for calculation. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.