Battery discharge depth detection method and system

Abstract

The embodiment of the invention discloses a battery discharge depth detection method and system. The battery discharge depth detection method comprises the following steps: discharging a to-be-detected battery according to a preset condition so as to control the to-be-detected battery to have a first state; detecting the open-circuit voltage of the battery to be detected; if the open-circuit voltage of the to-be-detected battery is smaller than a voltage threshold value, obtaining a phase angle of the to-be-detected battery in a preset frequency band based on an alternating-current impedance spectrum of the to-be-detected battery; and determining the residual capacity of the to-be-tested battery based on the phase angle of the preset frequency band and the corresponding relationship between the preset phase angle and the residual capacity. According to the discharge depth detection method provided by the embodiment of the invention, the influence of a passive film is eliminated, the discharge depth of the battery can be accurately evaluated, and the problem that the accurate discharge depth cannot be obtained when the open-circuit voltage of the battery is used for predicting the discharge depth in the prior art is solved.

Description

technical field [0001] Embodiments of the present invention relate to battery technology, and in particular to a method and system for detecting the depth of discharge of a battery. Background technique [0002] Compared with other primary batteries, lithium / thionyl chloride batteries have higher specific energy and higher working voltage, and their working temperature range is extremely wide, and the annual self-discharge rate is extremely low. Therefore, in the past ten years, more and more Many applications are in the fields of smart instrumentation, oil drilling, smart tracking, ETC, and national defense. [0003] For chemical power sources, the most important problem is the prediction of its availability, and people are very interested in estimating the remaining capacity of primary power sources in a non-destructive way. At present, the remaining capacity of the battery is estimated mainly by detecting the open circuit voltage. [0004] Lithium-sub-battery is a typic...

AI Technical Summary

Problems solved by technology

Therefore, it is difficult to obtain an accurate value using the open circuit voltage as the prediction basis for the depth of discharge of the lithium-ion battery.

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