Temperature detection circuit and temperature detection method of lithium battery pack

Abstract

The invention provides a temperature detection circuit and a temperature detection method of a lithium battery pack, the temperature detection circuit comprises a bridge circuit composed of four temperature-sensitive resistors, the temperature-sensitive resistors are arranged in a battery module, and the resistance values of the temperature-sensitive resistors change along with the temperature change of the battery module; the two output ends of the bridge circuit are electrically connected to the battery management unit, and the battery management unit is used for receiving and detecting the change of the resistance value of the temperature-sensitive resistor. According to the invention, the same number of temperature-sensitive resistors are arranged for each battery module in the unit, the temperature-sensitive resistors are constructed outside the module according to a certain sequence to form a bridge circuit, an output end matched with the battery management unit is provided for the battery management unit to acquire resistance data, the battery management unit converts the resistance value change to obtain temperature data, and the temperature data is stored in the battery management unit. The temperature detection scheme is low in cost and wide in application, a temperature sensing port does not need to be independently arranged on the battery module, and missing detection is avoided.

Description

Technical field [0001] The present invention belongs to the field of temperature detection technology, relates to a lithium battery pack temperature detection circuit and temperature detection method. Background [0002] In the current BMS battery management system, there are multiple battery modules, which are related to the stable operation of the entire battery management system, so it is very important to detect the temperature of the battery module. At present, the temperature and current of the module are monitored by the battery management system to prevent the module temperature from exceeding the allowable limit. [0003] CN110967635A discloses a temperature detection circuit and detection method, battery management system. The temperature detection circuit comprises: a temperature detection module for detecting the temperature of the battery module; a first trigger module, connected with a temperature detection module, for providing a first trigger signal when the temp...

AI Technical Summary

Problems solved by technology

[0006] Large-capacity lithium battery packs usually only have 1 to 2 strings of batteries due to their large capacity, which is not suitable for conventional BMUs with a limited number of temperature detection ports, because some modules may not have temperature sensing ports available, resulting in Missing module temperature detection brings hidden dangers to the safety of lithium battery packs

This shortcoming can be overcome by using digital temperature sensing technology, but the cost is higher

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