Method for detecting electrical property consistency of lithium ion battery

Abstract

The invention discloses a method for detecting the electrical property consistency of lithium ion battery. The method comprises the following steps of: performing formation storage and ageing storage on a plurality of monomer batteries for a long time one by one and selecting the battery with large self discharge; performing capacity grading treatment on the rest of qualified monomer batteries to obtain the actual battery volume C of the plurality of monomer batteries, charging the plurality of monomer batteries to the same charging state and classifying the plurality of batteries according to the volume difference standard; performing low-temperature direct-current internal resistance test on the plurality of batteries with the same volume difference standard grade and reclassifying the battery according to the direct-current internal resistance of the battery; and selecting and matching the plurality of batteries in the same direct-current internal resistance grade to form the battery pack. The invention can detect the electrical property consistency of the lithium ion battery under the low-temperature condition, effectively solve the problem that the battery has good electrical property consistency under the normal-temperature condition and differed electrical property consistency under the low-temperature condition and is suitable for detecting a batch of batteries and selecting qualified monomer batteries to form a battery pack.

Description

technical field [0001] The invention relates to the technical field of battery detection, in particular to a detection method for the consistency of electrical properties of lithium-ion batteries. Background technique [0002] At present, lithium-ion batteries have the incomparable advantages of other energy storage batteries, such as high energy density, light weight, and good safety performance. It has also been widely used in bicycles and electric vehicles, and it is also very attractive for military fields such as aerospace, aviation, and field operations. In addition, in the military field, high requirements are placed on the operating temperature range and energy of lithium-ion batteries. Generally, it is required to be able to work at least at a temperature of -40~60°C, and even at a temperature of -50°C. At present, high energy is mainly obtained by combining batteries in series and parallel. For example, 14.4V10Ah and 25.2V20Ah high-capacity battery packs can be ob...

AI Technical Summary

Problems solved by technology

[0009] In view of this, the purpose of the present invention is to provide a detection method for the consistency of electrical properties of lithium-ion batteries, which can detect the consistency of electrical properties of lithium-ion batteries under low temperature conditions, and effectively solve the problem of each single battery at room temperature. It shows good consistency of electrical properties under low temperature conditions, and the problem of large differences in electrical properties under low temperature conditions is suitable for testing large quantities of batteries, screening out qualified single cells to form battery packs, and ensuring that the battery packs are kept in a low temperature environment. It has excellent performance, so it can greatly enhance the product experience of battery users, and is suitable for large-scale production applications, which has great practical significance in production

Images