Calculate the life of the lithium battery according to the time or the number of cycles

To measure the performance of a lithium battery for how long it can be used, the industry stipulates that it is defined by the number of cycles. But in fact, the way users use them is ever-changing, because tests with different conditions are not comparable. For comparison, the definition of cycle life must be standardized. The national standard stipulates the cycle life test conditions and requirements of lithium batteries: charge for 150 minutes under a constant current and constant voltage mode 1C charging system under 25 degrees room temperature, and discharge under a constant current 1C discharge system to 2.75V as a cycle. The test ends when one discharge time is less than 36 minutes, and the number of cycles must be greater than 300. In fact, the number of cycles of lithium batteries is not only affected by the way users use them, but also related to the production technology level and material formulations of manufacturers producing lithium batteries. Lithium battery pack: This definition stipulates that the cycle life test is carried out in a deep charge and deep discharge method. It stipulates that the cycle life must exceed 300 times after being executed in this mode. The capacity will still be more than 60%. In fact, different cycle systems are obtained. The number of cycles is completely different. For example, the other conditions above remain unchanged, just change the 4.2V constant voltage voltage to 4.1V constant voltage voltage to test the cycle life of the same type of battery, so this battery is no longer a deep charge In this way, the number of cycle life can be increased by nearly 60% in the final test. Then if the cut-off voltage is increased to 3.9V for testing, the number of cycles should be increased several times. It doesn't make any sense to talk about the number of cycles aside from the rules, because the number of cycles is a measure of battery life, not an end! Misunderstanding: Many people like to use mobile phone lithium-ion batteries to automatically shut down and recharge. This is completely unnecessary. In fact, it is impossible for users to use the battery in accordance with the national standard test mode. No mobile phone will shut down at 2.75V, and its discharge mode is not a high-current constant-current discharge, but a mixture of GSM pulse discharge and normal low-current discharge. The way. There is another measure of cycle life, which is time. Some experts have proposed that the lifespan of lithium-ion batteries for general civilian use is 2 to 3 years. Based on the actual situation, for example, 60% of the capacity is used as the end of life, plus the aging effect of lithium-ion batteries, and the cycle life is expressed by time. As reasonable. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.