Detection method of battery

Abstract

The invention provides a detection method of a battery. The detection method comprises the following steps of: detecting an environment temperature of a place where the battery is located and keeping the environment temperature to be constant; discharging the fully charged battery according to a predetermined discharge mode until discharge voltage of the battery reduces to a first voltage threshold value, and acquiring the discharge capacity C1 of the battery; charging the discharged battery according to a predetermined charge mode until the battery is fully charged, and placing the fully charged battery for a predetermined time T; discharging the battery again according to the predetermined discharge mode until the discharge voltage of the battery reduces to the first voltage threshold value, and acquiring the discharge capacity C2 of the battery; and acquiring a self-discharge rate K of the battery according to the discharge capacity C1, the discharge capacity C2 and the predetermined time T. The detection method provided by the invention effectively solves a problem that self discharge judgment is inaccurate because a voltage platform of a lithium iron phosphate battery is too gentle. In addition, the detection method is simple to operate, high in reliability, and convenient for industrial production applications.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a battery detection method. Background technique [0002] With the increasing environmental pollution and the increasingly serious energy crisis, it is urgent to develop new energy vehicles that are energy-saving and environmentally friendly, and battery technology is the bottleneck that hinders the further development of new energy vehicles. Lithium-ion batteries have become the preferred power source for electric vehicles due to their high energy density, high power density, long cycle life, and good safety. In order to achieve a certain voltage, power and energy level, multiple single cells need to be used in series or in parallel to form a group, and the consistency of the single cells directly determines the performance of the battery pack. At present, the parameters for judging the consistency of a single battery mainly include capacity, voltage, internal resistance, and...

AI Technical Summary

Problems solved by technology

The voltage of lithium iron phosphate battery drops rapidly at the end of discharge, so the general method is to put the lithium iron phosphate battery aside for a period of time after discharge to calculate the self-discharge rate, but this method requires high consistency of the battery. Due to the inconsistency of the polarization state, the battery with large self-discharge cannot be screened well

It can be seen that the existing methods cannot effectively characterize the self-discharge rate of power batteries, especially lithium iron phosphate batteries.

Images