Novel lithium ion battery thermal runaway detection device capable of accurately positioning

Abstract

The invention discloses a novel lithium ion battery thermal runaway detection device capable of accurately positioning. The device comprises an air tightness device and a detection element. The air tightness device is of a hollow structure, the air tightness device sleeves the outer side of a pressure release valve of a battery cell and is connected with a shell of the battery cell, the detectionelement is arranged in the air tightness device, and the detection element is used for detecting parameter signals in the air tightness device and transmitting the parameter signals to a control system. The detection device has the advantages that the air tightness device provides a reliable detection environment for the detection element, the detection element arranged over the pressure release valve can instantly detect opening of the pressure release valve and send out a timely early warning signal, and a gas release valve can discharge gas in the air tightness device to prevent the air tightness device from being exploded and damaged. Meanwhile, the detection devices are in one-to-one correspondence with single batteries, so that the single batteries specifically subjected to thermal runaway in a lithium ion battery pack can be accurately positioned, and the control system can conveniently take control measures in time.

Description

technical field [0001] The invention relates to the technical field of automotive lithium battery detection, in particular to a detection device for precisely positioning thermal runaway of a new type of lithium ion battery. Background technique [0002] With the popularity of new energy, people are paying more and more attention to new energy vehicles, especially the safety of new energy vehicles. The safety accidents of new energy vehicles mainly come from combustion or explosion caused by battery thermal runaway. When the battery temperature is too high due to internal and external short circuit, overcharging, etc., the battery is prone to thermal runaway. At present, the method of improving the safety of new energy vehicles is to strengthen the monitoring of battery packs, and there is no substantial technology to avoid battery thermal runaway. [0003] The current early warning technology routes for battery safety include: 1) thermal runaway early warning technology b...

AI Technical Summary

Problems solved by technology

However, the batteries of new energy vehicles usually use battery packs to increase the energy storage capacity of the batteries. The BMS mainly manages and detects the overall working status of the battery pack, and cannot detect the working status of each battery cell. Moreover, when a battery When the early thermal runaway of a single cell occurs, the temperature, current and other parameters of the entire battery pack do not change much, resulting in a certain lag in the detection of the entire battery pack by the BMS

The early warning technology of thermal runaway based on gas detection is based on the fact that a large amount of gas substances will be generated inside the battery when the battery is thermally runaway, such as CO, CO 2 、H 2 、C 2 h 4 and C 2 h 6 etc., use sensors to detect gas substances to realize early warning of battery thermal runaway. However, the operating conditions and working environment of batteries are very complex, which puts extremely high demands on the repeatability, sensitivity, response and recovery time, and stability of sensors. requirements, and even lead to false positives

And the same sensor detects the detection of gas substances in the entire battery pack, and cannot locate a certain battery cell where thermal runaway occurs

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