Battery internal resistance measuring method and device based on DC pulse method

Abstract

The invention relates to a battery internal resistance measuring method and device based on a DC pulse method. The device includes an external measurement sampling resistor and a switch K which are connected with a battery to be measured in series to form a closed circuit, an excitation source which disconnects and turns off the switch K for multiple times within predetermined time, a sampling unit, a calculation unit and a control unit that controls the excitation source, the sampling unit and the calculation unit. The sampling of the method and device is realized through pulse discharge of the battery, long-time large-current discharge of the battery is avoided through a DC pulse method, harm to the battery is reduced, long-time DC discharge is converted into pulse discharge, the volumeof a product is reduced, product miniaturization is detected through a DC method, an original product only needs to modify software to realize pulse method measurement, and the cost is low; accurate calculation of voltage drop is realized through an iterative algorithm, thereby ensuring measurement accuracy; and the power consumption and heat emission quantity of the product are reduced, and the device life is prolonged.

Description

technical field [0001] The invention relates to a battery internal resistance measurement method and device based on a direct current pulse method. Background technique [0002] The size of the internal resistance of the battery is an important indicator to measure the performance of the battery, and it is of great significance to accurately measure the internal resistance of the battery. At present, the methods for measuring the internal resistance of the battery mainly include the load step-down method, the short-circuit current method, the unbalanced bridge method, the alternating current method, the dual-range measurement method, and the potentiometer method. These methods have their own advantages and disadvantages. The common problem is that the measurement steps are cumbersome, some measurement methods have measurement errors that cannot be ignored, and even some measurement methods (due to the long discharge time of the battery, etc.) have a certain impact on the bat...

AI Technical Summary

Problems solved by technology

There are two obvious disadvantages in the implementation strategy of the general DC method for measuring internal resistance: 1. Large discharge current, 0.6C; 2. Long discharge time. It is necessary to ensure the battery discharge time to correctly reflect the battery voltage drop change.

Two defects restrict the commercialization of DC method to measure internal resistance

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