Battery fault detection device and method

Abstract

The invention provides a battery fault detection device and method. The device comprises a control unit which is used for detecting the open-circuit voltage, the break-over voltage and the break-over current of a battery, wherein the break-over voltage and the break-over current are outputted for a preset number N times, and N is greater than 1; the control unit calculates the nth break-over voltage of the battery, the open-circuit voltage closest to the nth break-over voltage in the detection time and the nth break-over current of the battery to obtain the nth internal resistance value of the battery, and n is a positive integer and n is equal to 1 to N; when n is greater than or equal to 2, an absolute difference value between the (n-1) th internal resistance value and the nth internal resistance value of the battery is calculated, and a result obtained by dividing the absolute difference value by the (n-1) th internal resistance value is taken as the nth resistance variation of the battery; and whether the battery fails or not is judged according to the nth resistance variation of the battery.

Description

technical field [0001] The invention relates to the field of battery technology, in particular to a battery fault detection device and method. Background technique [0002] In the current prior art, if one of the batteries fails when a multi-cell battery pack is used, the multi-cell battery pack must stop working completely, otherwise the battery may explode or its lifespan may be shortened. Although there may be different battery fault detection methods today, there are two problems. First, even if the multi-cell battery packs on the market know that there is a battery fault, the battery pack can only choose to stop power supply, and cannot effectively eliminate it at the same time. The fault also maintains the stable power supply of the back-end system. Second, there is actually no accurate and effective battery fault detection method on the market. This is because the batteries on the market cannot obtain accurate open circuit voltage (OCV or offline voltage). The open c...

AI Technical Summary

Problems solved by technology

[0002] In the current prior art, if one of the batteries fails when using a multi-cell battery pack, the multi-cell battery pack must stop working entirely, otherwise it may cause battery explosion or shorten the service life.

Although there may be different battery fault detection methods today, there are two problems. First, even if the multi-cell battery packs on the market know that there is a battery fault, the battery pack can only choose to stop power supply, and cannot effectively eliminate it at the same time. The fault also maintains the stable power supply of the back-end system. Second, there is actually no accurate and effective battery fault detection method on the market. This is because the batteries on the market cannot obtain accurate open circuit voltage (OCV or offline voltage). The open circuit voltage must be measured after offline or before starting, so that the accurate internal resistance of the battery cannot be effectively obtained during the use of multiple batteries. Generally, the battery is modeled by resistance and voltage (open circuit or conduction voltage). Battery failure behavior; therefore, how to detect battery failure more effectively needs to be solved urgently

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