Battery pack assembly method

Abstract

The invention discloses a battery pack assembly method; the battery pack is a series battery pack, and the assembly method comprises the following steps: S1, electrical cores are mounted on a detection capacity-grading device, and the capacity of each electric core is recorded; S2, cyclic charge and discharge is performed according to a charge and discharge rate required by uses, and charge and discharge curves are recorded; S3, a change rate dQ / dV curve of the electric quantity of the discharge curve of each electric core along with the voltage is calculated, the dQ / dV curve has two peak values, voltage values corresponding to the peak values are found out according to the dQ / dV curve, then corresponding electric core electric quantity values are found out according to the voltage valuesin the discharge curve, and the difference value of the two electric quantity values is Dn; S4, each electric core is charged to 50% of the electric quantity, and the self discharge rate of each electric core is calculated; and S5, the Dn can be classified into a plurality of groups; each big group is divided into multiple middle groups according to the capacity of the electrical cores, and each middle group is divided into multiple small groups according to the self discharge rate; and during assembly, the multiple electric cores in the same small group are assembled.

Description

technical field [0001] The invention relates to a power battery pack, in particular to a method for assembling a power battery pack. Background technique [0002] Since 2014, the state has provided financial subsidies for the promotion of new energy vehicles, which has greatly promoted the progress of key technologies, key materials and application products of lithium-ion power batteries. The development of new energy vehicles is inseparable from the progress of chemical energy storage devices, and lithium-ion batteries, as the mainstream chemical energy storage batteries, have received great investment in research and development and industry. For power batteries in electric vehicles, the focus is on safety, reliability and life. The research on the single power battery in the early stage has been relatively perfect, and the service life theoretically meets the requirements of electric vehicles. There is no serious problem in safety, and the operating economy is gradually ...

AI Technical Summary

Problems solved by technology

The simplest matching group is single-parameter matching group, which only considers the rated capacity, which is the case for the early matching group, but single-parameter matching group, the battery pack made of single power battery with 1500 cycle life, the cycle life is less than 1 / 10 of the monomer

Dynamic matching, considering the degree of overlap of standard discharge curves, this method either has a very low matching rate, or fails to grasp the key essence, and it is difficult to exceed 1 / 3 of the life of the monomer after matching

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