Parallel single cell performance monitoring system and monitoring method

Abstract

The invention discloses a parallel single cell performance monitoring system and monitoring method. The system comprises a master control module, a voltage acquisition module, a current acquisition module and a current sensor. The maser control module is respectively connected with the voltage acquisition module and the current acquisition module through a CAN bus; the voltage signal joint of the voltage acquisition module is respectively connected with the anode and the cathode of a cell, and the temperature signal joint of the voltage acquisition module is connected with a temperature sensor; the current signal joint of the voltage acquisition module is connected with the current sensor; the master control module is used for receiving, storing and uploading single cell performance parameters transmitted by the current acquisition module and the voltage acquisition module; and the master control module detects insulation resistance of a battery pack and determines whether a fault occurs in a line by use of the relation between the voltage sum of each serially connected single cell and the total voltage of the battery pack. The system provided by the invention can realize measurement of performance parameters of any one single cell in the battery pack and is high in precision.

Description

technical field [0001] The invention relates to a battery performance monitoring system and a monitoring method, in particular to a performance monitoring system for parallel-connected monomer batteries. Background technique [0002] As the main power source of electric vehicles, the performance of batteries will directly affect the promotion of electric vehicles. To study the charge-discharge and cycle life characteristics of the battery, and to test the performance of the battery under different conditions has important theoretical significance and practical application value for the safety research of electric vehicles. [0003] As a commonly used device for monitoring battery performance parameters, the battery management system can generally realize the measurement of single-cell battery voltage, temperature, battery pack current, and battery pack voltage. The capacity requirements of the battery pack are met, and then multiple single-cell batteries are connected in se...

AI Technical Summary

Problems solved by technology

In practical applications, in order to ensure the consistency of the performance of each single cell in the battery pack, the single cells are screened when the battery pack is integrated, and the single cells with similar capacity and internal resistance are selected, but this method is still difficult. Ensure that the initial performance parameters of each single battery in the battery pack are completely consistent, and the working conditions of each single battery are not completely consistent

Even if each single battery in the battery pack has the same charge and discharge current, if there is a difference in the initial capacity of the single battery, it will still lead to differences in the charge and discharge rate and depth of each single battery

In addition, the difference in the internal resistance of a single battery in the battery pack will lead to uneven distribution of the temperature field in the battery pack, which will affect its working conditions

However, the existing battery detection system generally regards a single battery as a whole, and monitors the performance of a single battery as a description of the performance of the internal parallel single battery, lacking a single battery performance monitoring system in the actual sense

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