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CN-122017615-A - Method and device for monitoring failure gas of lithium ion battery

CN122017615ACN 122017615 ACN122017615 ACN 122017615ACN-122017615-A

Abstract

The invention relates to a method and a device for monitoring invalid gas of a lithium ion battery, belonging to the technical field of battery monitoring, wherein the method for monitoring the invalid gas of the lithium ion battery comprises the steps of obtaining the total mass change and the total mass change duration of the lithium ion battery, and the total discharge mass and the total discharge duration of the invalid gas; the method comprises the steps of determining a first gas release rate based on the total mass change and the total mass change duration of the lithium ion battery, determining a second gas release rate based on the total release mass and the total release duration of the failure gas, determining a first ratio based on the ratio between the first gas release rate and the second gas release rate, determining a second ratio based on the total mass change duration of the lithium ion battery and the total release duration of the failure gas, and determining the corrected total release mass of the failure gas based on the release rate of the failure gas, the first ratio and the second ratio. The invention effectively improves the accuracy of monitoring the failure gas of the lithium ion battery.

Inventors

  • MAO BINBIN
  • ZHAO YU
  • ZHANG YING
  • MA YONGFEI

Assignees

  • 武汉理工大学

Dates

Publication Date
20260512
Application Date
20260209

Claims (10)

  1. 1. A method for monitoring a lithium ion battery for a failure gas, comprising: Acquiring the total mass change amount and total mass change duration of the lithium ion battery, and the total mass discharge amount and total discharge duration of the failure gas in the process from the beginning to the end of the discharge of the failure gas of the lithium ion battery; Determining a first gas release rate based on the total mass change and the total mass change duration of the lithium ion battery, and determining a second gas release rate based on the total release mass and the total release duration of the failed gas; Determining a first ratio based on a ratio between a first gas bleed rate and a second gas bleed rate, and determining a second ratio based on a total mass change duration of the lithium ion battery and a total bleed duration of the failed gas; And determining the total amount of the release mass of the failure gas after correction based on the release rate of the failure gas, the first ratio and the second ratio, wherein the release rate of the failure gas is determined based on a differential result between the release mass of the failure gas and the release time period.
  2. 2. The method of claim 1, wherein determining the first gas bleed rate based on the total mass change and the total length of mass change of the lithium ion battery, and determining the second gas bleed rate based on the total mass bleed and the total length of bleed of the failed gas comprises: the first gas bleed rate and the second gas bleed rate are determined based on the following formulas: Wherein, the Indicating the rate of release of the first gas, Indicating the total amount of mass change of the lithium ion battery, Indicating the total duration of mass change of the lithium ion battery, Indicating a second gas bleed rate, Indicating the total amount of bleed mass of the failed gas, Indicating the total duration of the bleed of the spent gas.
  3. 3. The method of claim 1, wherein determining the first ratio based on a ratio between the first gas bleed rate and the second gas bleed rate, and determining the second ratio based on a total length of mass change of the lithium ion battery and a total length of bleed of the failed gas, comprises: The first ratio and the second ratio are determined based on the following formula: Wherein, the A first ratio is indicated and a second ratio is indicated, Indicating the rate of release of the first gas, Indicating a second gas bleed rate, A second ratio is indicated and is indicated, Indicating the total duration of mass change of the lithium ion battery, Indicating the total duration of the bleed of the spent gas.
  4. 4. The method of claim 1, wherein determining the corrected total amount of bleed mass of the spent gas based on the bleed rate of the spent gas, the first ratio, and the second ratio comprises: determining the total amount of bleed mass of the corrected fail gas based on the following formula: Wherein, the Indicating the total amount of bleed mass of the corrected fail gas, Indicating the total duration of the bleed of the spent gas, A first ratio is indicated and a second ratio is indicated, Indicating the rate of release of the spent gas, A second ratio is indicated and is indicated, Indicating the bleed mass of the spent gas.
  5. 5. The method for monitoring the failure gas of the lithium ion battery according to claim 1, characterized in that the method further comprises: The molar mass of the spent gas was determined based on the following formula: Wherein, the Indicating the molar mass of the spent gas, Indicating the volume ratio of the target gas component in the failure gas, Indicating the molar mass of the target gas component in the spent gas, the target gas component being any one of the gas components in the spent gas.
  6. 6. The method for monitoring the failure gas of a lithium ion battery according to claim 5, characterized in that the method further comprises: the density of the failure gas is determined based on the following formula: Wherein, the Indicating the density of the spent gas, Which is indicative of the pressure of the environment, Indicating the molar mass of the spent gas, Is a gas constant which is a function of the gas, Indicating the temperature of the failed gas vent.
  7. 7. The method for monitoring the failure gas of a lithium ion battery according to claim 6, characterized in that the method further comprises: the mass flow, velocity flow and jet velocity of the failed gas are determined based on the following formulas: Wherein, the Indicating the mass flow rate of the failed gas, Indicating the total amount of bleed mass of the corrected fail gas, Indicating the velocity flow rate of the failed gas, Indicating the density of the spent gas, Indicating the jet velocity of the spent gas, Indicating the area of the failed gas discharge port.
  8. 8. A spent gas monitoring apparatus for a lithium ion battery, comprising: The acquisition module is used for acquiring the total mass change amount and total mass change duration of the lithium ion battery, and the total mass discharge amount and total discharge duration of the failure gas in the process from the beginning to the end of the discharge of the failure gas of the lithium ion battery; The first determining module is used for determining a first gas release rate based on the total mass change and the total mass change duration of the lithium ion battery, and determining a second gas release rate based on the total release mass and the total release duration of the failure gas; The second determining module is used for determining a first ratio based on the ratio between the first gas release rate and the second gas release rate and determining a second ratio based on the total mass change duration of the lithium ion battery and the total release duration of the failure gas; and the third determining module is used for determining the total amount of the release mass of the failure gas after correction based on the release rate of the failure gas, the first ratio and the second ratio, and the release rate of the failure gas is determined based on the differential result between the release mass of the failure gas and the release duration.
  9. 9. A monitoring device comprising a memory and a processor, wherein, The memory is used for storing programs; The processor, coupled to the memory, is configured to execute the program stored in the memory to implement the steps in the method for monitoring a failure gas of a lithium ion battery according to any one of claims 1 to 7.
  10. 10. A computer readable storage medium storing a computer readable program or instructions which when executed by a processor is capable of carrying out the steps of the method for monitoring for a spent gas of a lithium ion battery according to any one of the preceding claims 1 to 7.

Description

Method and device for monitoring failure gas of lithium ion battery Technical Field The invention relates to the technical field of battery monitoring, in particular to a method and a device for monitoring failure gas of a lithium ion battery. Background Under different abusive conditions, lithium ion batteries can have severe side reactions inside, and a large amount of combustible and toxic gases are generated, so that pressure is suddenly increased, and explosion can be possibly caused. The timing, rate and composition of the gas release directly determine the kinetics and extent of the failure. Therefore, the dynamic characteristics of gas generation are mastered in real time, in situ and accurately, and the method is very important for revealing failure mechanisms, constructing a safety early warning model and optimizing system design. Currently, mainstream gas analysis methods (e.g., extracting gas through long pipelines to an offline analyzer) suffer from inherent drawbacks in that gas components dissipate distortion during transport, failing to reflect transient peaks and rapid changes. The defects enable the prior art to be incapable of constructing a dynamic function model for accurately describing the failure gas production of the lithium ion battery, and severely limit the effectiveness of safety simulation and active protection strategies of the lithium ion battery. Therefore, how to improve the accuracy of monitoring the failure gas of the lithium ion battery becomes a technical problem to be solved. Disclosure of Invention In view of the foregoing, it is necessary to provide a method and a device for monitoring the failure gas of a lithium ion battery, which are used for solving the problems of insufficient real-time performance and accuracy of the existing monitoring scheme for the failure gas of the lithium ion battery. In order to solve the above problems, in a first aspect, the present invention provides a method for monitoring a failure gas of a lithium ion battery, including: Acquiring the total mass change amount and total mass change duration of the lithium ion battery, and the total mass discharge amount and total discharge duration of the failure gas in the process from the beginning to the end of the discharge of the failure gas of the lithium ion battery; Determining a first gas release rate based on the total mass change and the total mass change duration of the lithium ion battery, and determining a second gas release rate based on the total release mass and the total release duration of the failed gas; Determining a first ratio based on a ratio between a first gas bleed rate and a second gas bleed rate, and determining a second ratio based on a total mass change duration of the lithium ion battery and a total bleed duration of the failed gas; And determining the total amount of the release mass of the failure gas after correction based on the release rate of the failure gas, the first ratio and the second ratio, wherein the release rate of the failure gas is determined based on a differential result between the release mass of the failure gas and the release time period. In one possible implementation manner, the determining the first gas release rate based on the total mass change amount and the total mass change duration of the lithium ion battery, and determining the second gas release rate based on the total mass release amount and the total release duration of the failure gas includes: the first gas bleed rate and the second gas bleed rate are determined based on the following formulas: Wherein, the Indicating the rate of release of the first gas,Indicating the total amount of mass change of the lithium ion battery,Indicating the total duration of mass change of the lithium ion battery,Indicating a second gas bleed rate,Indicating the total amount of bleed mass of the failed gas,Indicating the total duration of the bleed of the spent gas. In one possible implementation manner, the determining the first ratio based on the ratio between the first gas release rate and the second gas release rate, and determining the second ratio based on the total mass change duration of the lithium ion battery and the total release duration of the failure gas includes: The first ratio and the second ratio are determined based on the following formula: Wherein, the A first ratio is indicated and a second ratio is indicated,Indicating the rate of release of the first gas,Indicating a second gas bleed rate,A second ratio is indicated and is indicated,Indicating the total duration of mass change of the lithium ion battery,Indicating the total duration of the bleed of the spent gas. In one possible implementation manner, the determining the corrected total amount of the bleed mass of the failure gas based on the bleed rate of the failure gas, the first ratio, and the second ratio includes: determining the total amount of bleed mass of the corrected fail gas based on the following formula: Where