Introduction to lithium batteries

A lithium battery is a rechargeable battery whose working principle is that lithium ions move between the positive electrode and the negative electrode. During charging and discharging, Li+ intercalates and deintercalates back and forth between the two electrodes. In rechargeable batteries, lithium ions are extracted from the positive electrode and inserted into the negative electrode through the electrolyte. The negative electrode is in a state rich in lithium. When unloading, the situation is just the opposite. Batteries generally use materials containing lithium as electrodes. It is a representative of modern high-performance batteries. The electrochemical reaction formula of lithium batteries: Now we know that lithium batteries, this reversible reaction mode is the cradle reaction, the lithium ion Li+ runs from the positive electrode to the negative electrode through the separator. Discharge is just the opposite. This swing forms the basic principle of rechargeable lithium batteries. Lithium batteries do not contain highly toxic substances, and their impact is far less than that of lead-acid batteries. Lithium batteries have high energy density and high average output voltage. The self-discharge is small, and the battery performance is good, less than 2% per month (recyclable). There is no memory effect. The working temperature range is -20℃~60℃. Superior cycle performance, fast charging and discharging, charging efficiency up to 100%, and high output power. long lasting. They do not contain toxic and hazardous substances and are called green batteries. Lithium batteries and lithium batteries are different in technical concepts. Wang Fang, senior engineer and chief expert in the field of power lithium-ion batteries, the Secretary-General of the my country Automotive Technology Research Center and the Battery Testing and Application Technology Alliance, said that lithium batteries usually refer to batteries with lithium metal or lithium alloy as the negative electrode and use of non-hydrolytic Solution. Lithium batteries refer to rechargeable secondary batteries. They do not use lithium metal for the negative electrode and rely on the movement of the positive and negative electrodes between lithium ions to work. However, in daily life, people are used to referring to lithium batteries as lithium batteries or lithium batteries. Wang Fang refuted the online article mentioned in the dangerous goods of lithium batteries, saying that in contrast, traditional batteries such as lead-acid, nickel-chromium and nickel-metal hydride, and lithium batteries do not contain any toxic and harmful heavy metal elements and substances. , Such as lead, mercury, cadmium, relatively little pollution. The electrolyte is organic solvents and lithium salts, mostly non-toxic or low-toxic; the decomposition or hydrolysis products of lithium batteries are fluorine-containing compounds such as hydrofluoric acid, which are corrosive and toxic. Liu Haojie, a senior engineer at the 18th Research Institute of my country Electronics Technology Group, said that lithium batteries do not contain toxic substances, and the carbon and metal oxides in the cathode are basically non-toxic. Since the lithium battery is sealed, it will not come into contact with these substances during normal use. In any case, this impact is much smaller than the lead-acid batteries that are currently widely used. The life of the power lithium battery can reach 2000 cycles. The battery management system can limit the life of the overcharge and overdischarge of the lithium current. How long? Will shallow charge and overcharge affect the safety and life of the battery? There are many factors that determine the life of the lithium battery. , Including the characteristics of the system itself, as well as the manufacturing process and operating conditions. A good battery system, coupled with scientific system management, can achieve long-term service life. According to Wang Fang's analysis, according to the cut-off condition of capacity attenuation to 80% and 100% depth of discharge test, the current life of power lithium-ion batteries can basically reach 2000 cycles. Overcharge and overdischarge means that the voltage of the battery exceeds or falls below the specified cut-off voltage during the charging and discharging process, which may cause harm to the performance and life of the battery. But Ms. Wang said that the BMS battery management system in the battery will limit and protect the battery, restrict charging at low temperatures and charging at a suitable temperature. Wang Fang said that in order to ensure the safety of lithium batteries, there are a series of safety protection designs for battery cells, modules and battery systems to prevent battery overcharge temperature, and give an alarm and protection when abnormalities occur. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.