Briefly describe the development of UAV lithium batteries

The general-purpose polymer lithium battery has the above-mentioned polymer lithium battery to meet the important performance, etc., and can be suitable for drones of different heavyweights. The commonly used battery for drones is a T-type polymer lithium battery. One end of the power line is connected to a male and female connector (usually XT60) for energy output. The other end of the signal line usually uses voltage testers and other equipment to test general-purpose lithium polymer batteries. This is a low-cost power handling method for drones, but it will bring many problems. For example, first, the battery power cannot be monitored in real time. The risk of crashing. Second, there is no complete charge management and discharge management. After the charge and discharge are completed, the battery must be tested with a voltage tester. Third, it cannot handle the over-discharge problem. Fourth, because plugs are often used for connection, it is impossible to deal with the problem of plug aging. Fourth, the battery is flammable and explosive, which poses a great safety hazard. Fifth, it is inconvenient to recycle, and the lithium battery pollutes the environment. Fifth, the battery itself has a low energy density, which cannot meet the urgent needs of UAVs during long voyages. Sixth, it is inconvenient to disassemble and assemble, and the frequency of battery replacement for drones is high, which affects user experience. 2 Intelligent and intelligent polymer lithium battery is to directly hit the pain points of the use of the above-mentioned general polymer lithium battery. It has been optimized and designed, combined with the drone flight control system and optimized battery management system, to achieve intelligent management and control of the battery. In the battery structure, firstly, ABS+PC fire-resistant materials are selected to improve the protection level of the battery. Secondly, the integrated design of the quick charging port and the addition of a power control switch reflect the convenience of operation. Thirdly, the buckle design on the battery head facilitates quick disassembly. Finally, take into account the appearance of the battery and realize the commercialization of smart batteries. On the hardware, the battery is equipped with a BMS battery management system (BatteryManagementSystem, abbreviated BMS). BMS is an important link connecting UAV power lithium-ion battery and electric UAV. BMS is used to monitor and indicate the battery and capacitance status (voltage, temperature, current, remaining energy), and send an alarm signal (sound and light) to the user under abnormal conditions, and cut off the power transmission link according to the established control strategy to protect it. The battery thus prolongs the battery life. BMS is composed of three major parts: terminal module, central solution module and display module. The terminal module is responsible for measuring battery voltage and temperature, balancing battery energy, current sampling and SOC calculation, various alarm data appearing, and controlling the charging and discharging circuit; the display module is responsible for displaying battery data, giving sound and light alarms, and recording data. When the total number of system batteries is small, the central solution module can be combined with the terminal module to form an integrated BMS system to save costs. On the basis of the above-mentioned hardware and structure, real-time monitoring of the state of the intelligent lithium battery is realized through software algorithms. The disadvantage of the intelligent lithium battery is that there are many market versions and the battery is not compatible. The standardization of intelligent lithium batteries is an urgent issue to be addressed. 3 The development of solid-state lithium battery solid state is to deal with the safety hazards, environmental protection, low energy density and other issues of general-purpose lithium batteries. The energy density of existing liquid lithium batteries is generally only 130-160Wh/kg, and the ceiling is 300Wh/ About kg. And there is the disadvantage of long charging time and low safety. The energy density of the solid-state lithium battery will be much higher. The energy density of the all-solid-state lithium battery is up to 900Wh/kg, and the structure is safer, so it was once considered an ideal UAV power lithium-ion battery. In terms of working principle, there is no difference between solid-state lithium batteries and traditional lithium batteries. The two ends of the battery are the positive and negative poles of the battery, and the middle is the liquid electrolyte. Lithium ions move back and forth at both ends through the electrolyte to complete the charge and discharge process of the battery. The important difference is that the solid-state lithium battery only has a solid electrolyte. The density and structure of solid lithium batteries allow more charged ions to concentrate on one end, conduct more current, and thereby increase battery capacity. Solid-state lithium batteries have many advantages and broad prospects for development. Among them, the two most distinct advantages are higher energy density and safer operation. After using the all-solid electrolyte, the lithium battery does not need to use lithium-inserted graphite anode, but directly uses metal lithium as the anode, which can greatly reduce the amount of anode material and significantly increase the energy density of the entire battery. At present, many laboratories have been able to trial-produce all-solid-state batteries with an energy density of 300-400Wh/kg in small-scale batches. The solid-state battery will not pierce the diaphragm due to the appearance of lithium dendrites and cause a short circuit when working under high current, will not have side reactions at high temperatures, and will not burn due to the presence of gas. Use high nickel anode + quasi-solid electrolyte + silicon carbon anode to achieve 300Wh/Kg before 2020, use lithium-rich cathode + all solid electrolyte + silicon carbon/lithium metal anode battery to achieve 400Wh/Kg before 2025, fuel/lithium before 2030 The sulfur/air battery achieves 500Wh/Kg. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Classification and analysis of rechargeable batteries