Method for quickly and effectively comparing self-discharge rates of batteries

Abstract

The invention discloses a method for quickly and effectively comparing self-discharge rates of batteries. The method includes steps of 1), continuing charging the batteries in a constant-voltage and current-limiting manner when the batteries are in normal fully charged states, and stopping charging the batteries when charging currents are reduced to extremely low states or jump up and down at certain current values for a long time; 2), laying the batteries processed in the step 1) aside for a certain duration shorter than or equal to 7 days; 3), measuring open-circuit voltages of the batteries after the batteries are laid aside for the certain duration; and 4), comparing the open-circuit voltages measured in the step 3) to a standard value, determining that self-discharge of the batteries is abnormal if the open-circuit voltages are lower than the standard value, and determining that the self-discharge of the batteries are normal if the open-circuit voltages are higher than the standard value. The charging currents in the extremely low states are lower than or equal to 0.001C, and the long time is longer than or equal to 1 hour. Compared with the traditional method, the method for quickly and effectively comparing the self-discharge rates of the batteries has the advantages that the effectiveness for selecting the self-discharge rates of the batteries is obviously improved, and the method is applicable to large-scale selection, is high in selection efficiency and is effective.

Description

technical field [0001] The invention relates to a method for quickly and effectively comparing the self-discharge rates of batteries. Background technique [0002] With the country's increasing emphasis on environmental protection and the gradual enhancement of people's awareness of environmental protection, lithium-ion batteries are not only used in traditional digital products, but also more and more widely used in electric tools, electric bicycles, even electric vehicles and large energy storage device. When lithium-ion batteries are used in digital products such as mobile phones or cameras, since they are used alone and do not need to be connected in series and parallel between batteries, the requirements for the overall performance of the battery are relatively low, only the capacity and cycle performance are qualified. However, when it is applied to fields with high working voltage such as electric bicycles and electric vehicles, multiple batteries need to be connecte...

AI Technical Summary

Problems solved by technology

At present, there is a special instrument made by method one, but its price is high, and the measurement cycle of one battery is more than 12 hours, and only one battery can be tested at a time. Therefore, even if the test result is accurate in this way, the test cost is too high. It is not suitable for large-scale production and is currently only suitable for experiments; method 2 is a standard test method for the self-discharge rate of general lithium-ion batteries, but its disadvantage is that the measurement cycle is too long, and method 3 has a relatively short test cycle and can be carried out in batches Testing is also the selection method adopted by most manufacturers in production at present, so it can be called a traditional method of selecting and comparing the self-discharge rate of batteries, but the experiment proves that the selection effect is not satisfactory

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