Adaptability testing of lithium-ion batteries for electric bicycles

Don’t overcharge the lithium-ion battery of an electric bicycle. As the saying goes, everything should be done right. The lithium-ion battery charger of an electric vehicle will automatically stop charging when the battery is fully charged. There is no trickle that lasts more than 10 hours when charging with a nickel coin charger. If the lithium-ion battery of an electric bicycle is fully charged, it will be wasted on the charger. At the same time, the lithium-ion battery of electric bicycles takes a long time to charge, usually at night. However, according to the actual situation of my country's power grid, in many places, the voltage is high at night and fluctuates greatly, especially lithium-ion batteries, which are very fragile and far less resistant to fluctuations in charge and discharge than nickel batteries, which bring additional risks. So someone must be there when charging the battery, just in case! However, none of us can guarantee that the characteristics of the lithium-ion battery charge-discharge protection circuit will never change. The quality of the lithium-ion battery is always foolproof, so it will be given for a long time. Charging a lithium-ion battery puts the lithium-ion battery on the edge of danger. This is another argument against the long-term allegations. The lithium-ion battery of an electric bicycle should have good environmental adaptability performance to truly achieve the effect of safe and long-term use, so how to test its performance? 1. Low temperature capacity: Put the battery pack in a low temperature box at -10°C Leave it for 8 hours, and then continue to discharge with 5.0a current until the end-of-discharge voltage is 27.5v or protect the battery pack; 2. High temperature capacity: Place in a high temperature box at 40℃ for 8 hours, and continue to discharge with 5.0a current until the discharge is terminated. The voltage is 27.5v or protect the battery pack; 3. Charging maintenance: store for 30 days after charging, discharge at 5.0a current until the end of discharge voltage is 27.5v or protect the battery pack; 4. Cycle life: leave it for at least 10 minutes, and then Continuous discharge of 5.0a current to 27.5v discharge termination voltage or battery pack protection, complete a charge-discharge cycle, and repeat the charge-discharge cycle. After the electric bicycle lithium-ion battery passes the above test, if the battery shell does not deform, the voltage change before and after the battery test does not exceed ±2.0v, and the battery pack does not leak, catch fire, or explode, it is qualified. Among all electrochemical systems, these two systems have the longest storage time, the highest working voltage, and different requirements for ambient temperature. 1. 150°C and 175°C batteries need special design; 2. No special design is required for batteries less than or equal to 100°C, and the batteries on the market can be used after appropriate improvements; 3. The battery temperature is lower than or equal to 125°C, as long as the Proper adjustment and control on the basis of the traditional battery production process can produce qualified products; 4. Regarding batteries above 180c and 200c, the lithium melting point of 180.5c is no longer suitable for negative electrodes, so lithium alloys should be used as negative electrodes. . Because the domestic demand for high-temperature batteries is not strong, and the production of the alloy requires higher investment in safety protection measures, this work has not yet been carried out. Disclaimer: Some pictures and content of articles published on this site are from the Internet, please contact to delete if there is any infringement. Previous: Introduction to the structure of solar lithium-ion battery