Energy storage explosion venting method and system

Abstract

The invention discloses an energy storage explosion venting method and system, and belongs to the technical field of energy storage safety protection, and the method comprises the steps: monitoring battery state parameters in real time through a battery management system, detecting thermal runaway characteristic gas in combination with a gas sensor, and judging and confirming the occurrence of a thermal runaway event; after thermal runaway is confirmed, an external combustible gas storage device is started, and according to the pre-calculated effective volume of the energy storage system, combustible gas with the gas concentration within the safe explosion range is accurately inflated into the energy storage system; when the gas concentration reaches the preset threshold value, the ignition device is started immediately, controllable local explosion is triggered, and therefore the explosion venting plate is opened accurately and reliably. By actively controlling the time and power of explosion, unpredictable thermal runaway explosion is converted into a manageable safe explosion venting process, destructive explosion caused by too high gas concentration is effectively avoided, and the safety and reliability of the energy storage system are remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage safety protection, and more particularly to an energy storage explosion relief method and system. BACKGROUND

[0002] Generally, after a lithium battery experiences thermal runaway, a large amount of hydrogen and carbon monoxide will be generated, accompanied by electrolyte vapor and high pressure sparking. If a spark is generated, an explosion will occur when the concentration of hydrogen and carbon monoxide reaches a certain concentration. In order to release the explosion, an explosion relief device needs to be installed in the energy storage system, which will open first to release the explosion energy when the explosion occurs. However, when the concentration of these flammable gases is low, the result of the explosion is only to open the explosion relief device without damaging other components. When the concentration is high, the impact force generated by the explosion will be very large, which will not only blow off the explosion relief plate, but also cause a large impact on the entire container. In severe cases, the container will be blown apart, and the explosion debris will damage the surrounding energy storage equipment. In this design method, the timing of opening the explosion relief plate depends on when the energy storage system will spark, and the energy storage system sparking has strong randomness and cannot be accurately controlled. If the internal gas is ignited actively, the explosion relief plate can be opened by explosion, but since the battery thermal runaway situation is complex, it is difficult to control the ignition timing. If the ignition point is too early, the explosion relief plate cannot be blown off, and if the ignition point is too late, the concentration is high, which will lead to uncontrolled explosion and cause a large power explosion.

[0003] Therefore, how to provide an energy storage explosion relief method and system that can accurately control the ignition timing of the energy storage system so that the impact force generated by the explosion can just open the explosion relief plate without damaging the energy storage system is a problem that those skilled in the art need to solve. SUMMARY

[0004] Therefore, the present application provides an energy storage explosion relief method and system, which calculates the gas volume that needs to be released inward according to the effective volume of the energy storage device, and accurately opens the explosion relief plate near the ignition device when the gas concentration reaches the lower limit through the ignition device.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions: On the one hand, the present application provides an energy storage explosion relief method, which comprises: obtaining battery state parameters and gas parameters inside the energy storage system, and determining whether a thermal runaway event occurs based on the battery state parameters and the gas parameters; releasing flammable gas into the energy storage system when it is detected that a thermal runaway event occurs; calculating the gas volume range that makes the gas concentration within a safe explosion range according to the effective volume of the energy storage system; According to the gas volume, when the gas concentration reaches the safe explosion range, the ignition device is started to cause a controllable explosion.

[0006] Preferably, the battery state parameters and gas parameters inside the energy storage system are acquired, and whether a thermal runaway event occurs is determined based on the battery state parameters and the gas parameters, including: The voltage data of each battery monomer is collected in real time, and when it is detected that the voltage of any battery monomer decreases by more than a preset voltage threshold within a preset time threshold, it is determined that the battery state is abnormal; Whether a thermal runaway characteristic gas appears is detected by a gas sensor, and the thermal runaway characteristic gas includes hydrogen, carbon monoxide, or a combination of the two; When the battery state is abnormal and the thermal runaway characteristic gas is detected at the same time, it is determined that a thermal runaway event occurs.

[0007] Preferably, the gas sensor is a hydrogen sensor, a carbon monoxide sensor, or a two-in-one composite gas sensor.

[0008] Preferably, the gas volume range that makes the gas concentration within the safe explosion range is calculated according to the effective volume of the energy storage system, as follows:

[0009] Among them, is the minimum hydrogen concentration for the explosion of the energy storage system; is the maximum hydrogen concentration for the explosion of the energy storage system; is the effective volume of the energy storage system, is the required inflation gas volume.

[0010] Preferably, the hydrogen concentration in the safe explosion range is 4% to 30%.

[0011] In another aspect, the present application provides an energy storage explosion relief system, comprising: A monitoring module is configured to acquire battery state parameters and gas parameters inside the energy storage system, and determine whether a thermal runaway event occurs based on the battery state parameters and the gas parameters; A calculation module is configured to calculate a gas volume range that makes the gas concentration within a safe explosion range according to the effective volume of the energy storage system; A combustible gas storage device stores combustible gas, and is configured to release the combustible gas into the energy storage system through a gas channel when it is detected that a thermal runaway event occurs; An ignition device is configured to cause a controllable explosion when the gas concentration reaches the safe explosion range.

[0012] Compared with the prior art, the energy storage and explosion relief method and system provided by the application can convert unpredictable and power random thermal runaway explosion into active explosion with predictable time and power by actively injecting combustible gas into the energy storage system and accurately controlling the concentration of the combustible gas in the safe explosion range. The destructive explosion caused by the natural accumulation of combustible gas with too high concentration is fundamentally avoided, the disintegration of the energy storage container is effectively prevented, and the safety level of the entire energy storage system is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0014] Figure 1 The flowchart provided by the present application.

[0015] Figure 2 The structural diagram provided by the present application. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0017] The embodiments of the present application disclose an energy storage explosion relief method provided by the present application, as shown in the figure, comprising: Figure 1 acquiring battery state parameters and gas parameters inside the energy storage system, and determining whether a thermal runaway event occurs based on the battery state parameters and the gas parameters; releasing combustible gas into the energy storage system when detecting that a thermal runaway event occurs; calculating the gas volume range that makes the gas concentration in the safe explosion range according to the effective volume of the energy storage system; inflating according to the gas volume, and starting the ignition device to cause a controllable explosion when the gas concentration reaches the safe explosion range.

[0018] Further, acquiring battery state parameters and gas parameters inside the energy storage system, and determining whether a thermal runaway event occurs based on the battery state parameters and the gas parameters, comprises: ​Real-time acquisition of voltage data of each battery monomer, when detecting that the voltage of any battery monomer decreases by more than a preset voltage threshold within a preset time threshold, determining that the battery state is abnormal; Specifically, the sampling line is arranged on the positive and negative poles of the battery cell to collect the voltage.

[0019] Detecting whether a thermal runaway characteristic gas appears through a gas sensor, the thermal runaway characteristic gas including hydrogen, carbon monoxide, or a combination of both; When the battery state is abnormal and the thermal runaway characteristic gas is detected at the same time, it is determined that a thermal runaway event occurs.

[0020] Further, the gas sensor is a hydrogen sensor, a carbon monoxide sensor, or a two-in-one composite gas sensor.

[0021] Further, the gas sensor is a hydrogen sensor, a carbon monoxide sensor, or a two-in-one composite gas sensor.

[0022] wherein, is the minimum hydrogen concentration for explosion of the energy storage system; is the maximum hydrogen concentration for explosion of the energy storage system; is the effective volume of the energy storage system, which is a fixed value and is generally determined when the energy storage system is designed, is the required inflation gas volume.

[0023] In the present embodiment, although the battery thermal runaway also produces hydrogen, there is a certain time delay from the detection of the battery thermal runaway to the release into the energy storage container, and generally, a rapid voltage drop represents that the battery has occurred thermal runaway, and the gas is first released to the Pack bag on which a pressure relief valve is arranged. When the pressure reaches a certain degree, the thermal runaway gas pushes open the pressure relief valve, the thermal runaway gas enters the energy storage cabinet, and the gas propagation in the cabinet also needs a certain time. Before the gas propagates to the vicinity of the explosion venting plate, the inflation and ignition operation to occur partial explosion to open the explosion venting plate can be completely completed, and therefore, the influence of the hydrogen produced by the thermal runaway can be ignored in the calculation.

[0024] Further, in order to improve safety, the influence of the hydrogen produced by the thermal runaway can be offset by multiplying a certain safety factor.

[0025] Generally, the hydrogen concentration in the safe explosion range is 4% to 30%.

[0026] On the other hand, the present application provides an energy storage explosion venting system, as shown in Figure 2 comprising: a monitoring module for acquiring battery state parameters and gas parameters inside the energy storage system, and determining whether a thermal runaway event occurs based on the battery state parameters and the gas parameters; The calculation module is used to calculate the range of filling gas volume that keeps the gas concentration within the safe explosion range based on the effective volume of the energy storage system. A combustible gas storage device that stores combustible gas and is used to release combustible gas into the energy storage system through a gas channel when a thermal runaway event is detected. An ignition device is used to trigger a controlled explosion when the gas concentration reaches a safe explosion range.

[0027] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0028] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for energy storage and explosion venting, characterized in that, include: Obtain battery state parameters and gas parameters inside the energy storage system, and determine whether a thermal runaway event has occurred based on the battery state parameters and gas parameters; When a thermal runaway event is detected, combustible gas is released into the energy storage system. The volume range of the filling gas that keeps the gas concentration within the safe explosion range is calculated based on the effective volume of the energy storage system. Gas is introduced according to the gas volume. When the gas concentration reaches the safe explosion range, the ignition device is activated to trigger a controlled explosion.

2. The energy storage explosion venting method according to claim 1, characterized in that, Acquire battery state parameters and gas parameters inside the energy storage system, and determine whether a thermal runaway event has occurred based on the battery state parameters and gas parameters, including: The voltage data of each battery cell is collected in real time. When the voltage of any battery cell drops by more than a preset voltage threshold within a preset time threshold, it is determined that the battery is in an abnormal state. The presence of thermal runaway characteristic gases is detected by a gas sensor, including hydrogen, carbon monoxide, or a combination of both. A thermal runaway event is determined to have occurred when both an abnormal battery condition and the detection of a gas characteristic of thermal runaway are met simultaneously.

3. The energy storage explosion venting method according to claim 2, characterized in that, The gas sensor is a hydrogen sensor, a carbon monoxide sensor, or a combined gas sensor.

4. The energy storage explosion venting method according to claim 1, characterized in that, Based on the effective volume of the energy storage system, the range of filling gas volume that keeps the gas concentration within the safe explosion range is calculated as follows: in, The minimum hydrogen concentration required for an energy storage system to explode; This represents the highest hydrogen concentration that could cause an energy storage system explosion. The effective volume of the energy storage system The required volume of inflatable gas.

5. The energy storage explosion venting method according to claim 4, characterized in that, The safe explosion range for hydrogen concentration is 4% to 30%.

6. An energy storage and explosion relief system, characterized in that, include: The monitoring module is used to acquire battery status parameters and gas parameters inside the energy storage system, and to determine whether a thermal runaway event has occurred based on the battery status parameters and gas parameters. The calculation module is used to calculate the range of filling gas volume that keeps the gas concentration within the safe explosion range based on the effective volume of the energy storage system. A combustible gas storage device that stores combustible gas and is used to release combustible gas into the energy storage system through a gas channel when a thermal runaway event is detected. An ignition device is used to trigger a controlled explosion when the gas concentration reaches a safe explosion range.

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