What is the internal resistance of the battery and how to measure it?

What is the self-discharge of secondary batteries? What is the self-discharge rate of different types of batteries? Self-discharge is also called charging capacity, which refers to the ability of the battery to store under certain environmental conditions under open circuit conditions. Generally speaking, self-discharge is mainly affected by manufacturing processes, materials, and storage conditions. Self-discharge is one of the primary parameters to measure battery function. Generally speaking, the lower the storage temperature of the battery, the lower the self-discharge rate. But it should be noted that too low or too high temperature may damage the battery and make it unusable. BYD's conventional battery requires a storage temperature plan of -20~45. After the battery is left open for a period of time, a certain degree of self-discharge is normal. The IEC standard stipulates: After nickel-cadmium batteries and nickel-hydrogen batteries are fully charged, they are turned on for 28 days at 20 degrees and 65% humidity, and the discharge time of 0.2c is greater than 3 hours, 3 hours and 15 minutes, respectively. Compared with other rechargeable battery systems, the self-discharge rate of solar cells containing liquid electrolytes is significantly reduced, about 10%/month, which is 25. What is the internal resistance of the battery? How to measure it? The internal resistance of the battery is the point of battery operation. The current flows through the internal resistance of the battery. It is generally divided into AC resistance and DC resistance. The ability of the electrode to polarize, the polarization resistance, in fact it cannot be measured by value, and the AC impedance measurement can abolish the polarization resistance and the effect of the solution on the actual value. The test method of AC internal resistance is as follows: using the characteristics of the battery, equivalent to an active resistor, the battery is given a stable 1000 Hz and 50ma current, voltage sampling, correction and filtering, and a series of treatments for accurate measurement of resistance value. What is the internal pressure of the battery? What is the normal internal pressure of the battery? The internal pressure of the battery is the pressure of gas that appears during the charging and discharging of the battery. It is mainly affected by process factors such as the manufacturing process and structure of battery materials. Under normal circumstances, the internal pressure of the battery is maintained at a normal level. If the rate of the recombination reaction is lower than the rate of the decomposition reaction, the sudden gas will not be consumed in time, resulting in increased battery pressure. What is internal pressure test? Lithium battery internal pressure test: (UL standard) simulates the battery at an altitude of 15,240 meters (low pressure 11.6kPa), check whether the battery leaks or drums. Specific steps: Charge the battery with 1C constant current and constant voltage to 4.2v, cut-off current 10mA, store in a low-pressure box, pressure 11.6kpa, temperature (20+_3), and store for 6 hours. The battery will not explode, catch fire, tear or leak. Disclaimer: Some pictures and content of the articles published on this site are from the Internet, please contact to delete if there is any infringement. Previous: Explanation of the composition of lithium battery electrolyte