Battery pack, electric equipment and control method of battery pack

Abstract

The invention provides a battery pack, electric equipment and a control method of the battery pack. The battery pack comprises a shell, a battery and a resonator. Wherein the shell is provided with an accommodating cavity; the battery is arranged in the containing cavity. The resonator is provided with a resonant cavity, the resonant cavity is communicated with the accommodating cavity, the resonator outputs a corresponding signal according to the change of the gas density in the resonant cavity, and the signal output by the resonator is used for monitoring the battery pack. According to the technical scheme, the state of the battery pack can be obtained in time so that the battery pack can be monitored conveniently.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery pack, an electrical device, and a control method for the battery pack. Background Art

[0002] Battery packs are widely used in electric vehicles, energy storage systems, portable electronic devices, industrial equipment and other fields.

[0003] In the related art, when a battery pack is in use, it is necessary to obtain the status of the battery pack in order to intervene in abnormalities of the battery pack.

[0004] However, in the related art, the acquisition of the battery pack status is relatively delayed. This delay makes it impossible to detect abnormalities in the battery pack in a timely manner, thereby causing safety problems. Summary of the Invention

[0005] Embodiments of the present invention provide a battery pack, an electric device, and a method for controlling the battery pack, which are intended to obtain the status of the battery pack in a relatively timely manner to facilitate monitoring of the battery pack.

[0006] In a first aspect, an embodiment of the present invention provides a battery pack, comprising:

[0007] A housing is provided with a receiving cavity;

[0008] a battery, disposed in the receiving cavity; and

[0009] The resonator is provided with a resonant cavity, the resonant cavity is connected to the receiving cavity, the resonator outputs a corresponding signal according to the change of gas density in the resonant cavity, and the signal output by the resonator is used to monitor the battery pack.

[0010] In one embodiment, the resonator is disposed in the receiving cavity;

[0011] And / or, the resonator is configured as a piezoelectric resonator, an electrostatic resonator or a capacitive resonator.

[0012] In one embodiment, the resonator includes a vibration excitation part, a signal pickup part and a support ring, the vibration excitation part and the signal pickup part are respectively arranged at both ends of the support ring, the vibration excitation part, the signal pickup part and the support ring jointly enclose the resonant cavity, the vibration excitation part is used to generate vibration to drive the signal pickup part to generate vibration, and the signal pickup part is used to detect the vibration and convert it into a signal output by the resonator.

[0013] In one embodiment, the vibration excitation portion includes a vibration excitation body and a first vibration amplifying portion, and the first vibration amplifying portion is provided on the vibration excitation body;

[0014] And / or, the signal pickup unit includes a signal pickup body and a second vibration amplifying unit, and the second vibration amplifying unit is provided on the signal pickup body;

[0015] And / or, the signal pickup portion is provided with a communication hole, and the resonant cavity is connected to the receiving cavity through the communication hole.

[0016] In one embodiment, the resonator is disposed above the battery.

[0017] In one embodiment, the resonant cavity is cylindrical, and the inner diameter of the resonant cavity ranges from 5 mm to 200 mm;

[0018] And / or, the height of the resonant cavity ranges from 1 mm to 300 mm.

[0019] In one embodiment, the battery pack further includes a spray system provided on the shell, wherein the spray system is connected to the resonator, and the spray system is used to spray the battery according to the signal output by the resonator.

[0020] In a second aspect, an embodiment of the present invention provides an electrical device including the aforementioned battery pack.

[0021] In a third aspect, an embodiment of the present invention provides a control method for a battery pack, wherein the battery pack includes a housing, a battery, and a resonator, wherein the housing has a receiving cavity, the battery is disposed in the receiving cavity, the resonator has a resonant cavity, the resonant cavity is communicated with the receiving cavity, the resonator is configured to vibrate gas within the resonant cavity, and the resonator outputs a corresponding signal based on changes in gas density within the resonator. The control method includes:

[0022] obtaining a detection signal of the resonator;

[0023] The battery pack is monitored according to the detection signal.

[0024] In one embodiment, monitoring the status of the battery pack according to the detection signal includes:

[0025] When the detection signal is different from the first reference signal, it is determined that the battery pack is in a thermal runaway state.

[0026] In one embodiment, the signal output by the resonator decreases as the density of the gas in the resonant cavity decreases;

[0027] When the detection signal is different from the first reference signal, determining that the battery pack is in a thermal runaway state includes:

[0028] When the detection signal is less than the first reference signal, it is determined that the battery pack is in a thermal runaway state.

[0029] In one embodiment, when the detection signal is less than the first reference signal, it is determined that the battery pack is in a thermal runaway state;

[0030] When the detection signal is different from the first reference signal, determining that the battery pack is in a thermal runaway state includes:

[0031] When the detection signal is less than the first reference signal and greater than or equal to a second reference signal, determining that the battery pack is in a first thermal runaway state;

[0032] When the detection signal is less than the second reference signal and greater than or equal to a third reference signal, determining that the battery pack is in a second thermal runaway state;

[0033] When the detection signal is less than the third reference signal, it is determined that the battery pack is in a third thermal runaway state.

[0034] Monitoring the battery pack according to the detection signal includes:

[0035] Acquiring the gas concentration of the gas to be detected according to the detection signal;

[0036] When the gas concentration is less than a first reference concentration and greater than or equal to a second reference concentration, determining that the battery pack is in a first thermal runaway state;

[0037] When the gas concentration is less than the second reference concentration and greater than or equal to a third reference concentration, determining that the battery pack is in a second thermal runaway state;

[0038] When the gas concentration is less than the third reference concentration, it is determined that the battery pack is in a third thermal runaway state.

[0039] In one embodiment, the battery pack further includes a spray system provided on the housing, and the spray system is connected to the resonator;

[0040] The control method further includes:

[0041] When the battery pack is in the first thermal runaway state, reducing the discharge power of the battery pack;

[0042] When the battery pack is in the second thermal runaway state, stopping charging and discharging of the battery pack;

[0043] When the battery pack is in the third thermal runaway state, the spray system is controlled to turn on.

[0044] Beneficial effects of the embodiments of the present invention:

[0045] In an embodiment of the present invention, since the resonant cavity is connected to the receiving cavity, once the gas density in the receiving cavity changes, the gas density in the resonant cavity will also change accordingly, so that the signal output by the resonator will also change accordingly, thereby enabling the battery pack status to be obtained more timely, so as to facilitate monitoring of the battery pack. There are many situations that cause the gas density in the receiving cavity to change. For example, when the battery pack experiences thermal runaway, the battery will release gas into the receiving cavity. Since the resonant cavity is connected to the receiving cavity, the gas can enter the resonant cavity more quickly, thereby changing the gas density in the resonant cavity, thereby causing the signal output by the resonator to change. Based on the signal output by the resonator, the battery pack status can be obtained, and abnormal battery pack status can be detected in time. For another example, if the shell is damaged, the receiving cavity is connected to the external environment, and external gas enters the receiving cavity, causing the gas density in the receiving cavity to change, thereby changing the gas density in the resonant cavity, thereby causing the signal output by the resonator to change. Based on the signal output by the resonator, the battery pack status can be obtained, and abnormal battery pack status can be detected in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 is a three-dimensional schematic diagram of a battery pack provided by an embodiment of the present invention;

[0048] Figure 2 yes Figure 1 Schematic diagram of the structure of the battery pack after the shell is hidden;

[0049] Figure 3 yes Figure 1 A perspective view of the battery pack;

[0050] Figure 4 yes Figure 3 a cross-sectional view of the middle resonator;

[0051] Figure 5 is a flow chart of a method for controlling a battery pack according to an embodiment of the present invention;

[0052] Figure 6 is a flow chart of a method for controlling a battery pack according to an embodiment of the present invention;

[0053] Figure 7 This is a flow chart of a method for controlling a battery pack provided by an embodiment of the present invention.

[0054] Description of reference numerals:

[0055] 100, battery pack; 200, shell; 210, receiving cavity; 300, battery; 400, resonator; 410, resonant cavity; 420, vibration excitation unit; 421, vibration excitation body; 422, first vibration amplification unit; 430, signal pickup unit; 431, signal pickup body; 432, second vibration amplification unit; 440, support ring; 450, connecting hole; 500, spray system; 510, nozzle; 520, liquid reservoir; 600, battery management system. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present invention, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0057] According to the first aspect of this application, referring to Figures 1 to 4 The present disclosure provides a battery pack 100, comprising a housing 200, a battery 300, and a resonator 400. The housing 200 defines a receiving chamber 210. The battery 300 is disposed within the receiving chamber 210. The resonator 400 defines a resonant cavity 410, which communicates with the receiving chamber 210. The resonator 400 outputs a signal corresponding to changes in gas density within the resonant cavity 410. The signal output by the resonator 400 is used to monitor the status of the battery pack 100.

[0058] Since the resonant cavity 410 is connected to the containing cavity 210, once the gas density in the containing cavity 210 changes, the gas density in the resonant cavity 410 will also change accordingly, so that the signal output by the resonator 400 will also change, thereby making it possible to obtain the status of the battery pack 100 more timely, so as to facilitate monitoring of the battery pack 100.

[0059] There are many situations that can cause changes in the gas density within the receiving cavity 210. For example, when the battery pack 100 experiences thermal runaway, the battery 300 releases gas into the receiving cavity 210. Since the resonant cavity 410 is connected to the receiving cavity 210, the gas can enter the resonant cavity 410 more quickly, thereby changing the gas density within the resonant cavity 410, and thus causing the signal output by the resonator 400 to change. Based on the signal output by the resonator 400, the status of the battery pack 100 can be obtained, and abnormalities in the battery pack 100 can be detected in a timely manner. For another example, if the housing 200 is damaged, the receiving cavity 210 is connected to the external environment, and external gas enters the receiving cavity 210, causing the gas density within the receiving cavity to change, thereby changing the gas density within the resonant cavity 410, and thus causing the signal output by the resonator 400 to change. Based on the signal output by the resonator 400, the status of the battery pack 100 can be obtained, and abnormalities in the battery pack 100 can be detected in a timely manner.

[0060] In one embodiment, the resonator 400 is disposed within the receiving cavity 210. This facilitates a more compact structure and miniaturization of the battery pack 100. Furthermore, since the resonator 400 is located within the receiving cavity 210, it is protected by the housing 200 of the battery pack 100. However, this design is not limited thereto; in other embodiments, the resonator 400 may partially penetrate the housing 200, thereby connecting the resonant cavity 410 and the receiving cavity 210.

[0061] There are many types of resonators 400 . In one embodiment, the resonator 400 is configured as a piezoelectric resonator 400 , an electrostatic resonator 400 , or a capacitive resonator 400 .

[0062] In one embodiment, the resonator 400 includes a vibration excitation portion 420, a signal pickup portion 430 and a support ring 440. The vibration excitation portion 420 and the signal pickup portion 430 are respectively arranged at both ends of the support ring 440. The vibration excitation portion 420, the signal pickup portion 430 and the support ring 440 jointly enclose a resonant cavity 410. The vibration excitation portion 420 is used to generate vibration to drive the signal pickup portion 430 to generate vibration. The signal pickup portion 430 is used to detect the vibration and convert it into a signal output by the resonator 400.

[0063] The vibration excitation unit 420 and the signal pickup unit 430 are respectively arranged at both ends of the support ring 440, which can ensure the efficient transmission of vibration and the accurate pickup of signals. This layout enables the vibration generated by the vibration excitation unit 420 to directly act on the signal pickup unit 430, thereby improving the sensitivity and accuracy of signal detection, and providing a more reliable basis for determining the status of the battery 300. In addition, the vibration excitation unit 420 is not only used to generate vibrations, but is also reused as a component that encloses the resonant cavity 410 together with other components, which makes the resonator 400 more integrated. In addition, the signal pickup unit 430 is not only used to detect vibrations and convert them into signals output by the resonator 400, but is also reused as a component that encloses the resonant cavity 410 together with other components, which makes the resonator 400 more integrated.

[0064] However, the present design is not limited thereto. In some other embodiments, the structure of the resonator 400 may be other, as long as it can vibrate the gas in the resonant cavity 410 and the resonator 400 outputs a corresponding signal according to the change in the gas density in the resonant cavity 410. No limitation is imposed here.

[0065] In one embodiment, the vibration exciting portion 420 includes a vibration exciting body 421 and a first vibration amplifying portion 422 , and the first vibration amplifying portion 422 is disposed on the vibration exciting body 421 .

[0066] The first vibration amplifier 422 amplifies the vibrations generated by the vibration excitation body 421, thereby enhancing the intensity and detectability of the vibrations. This design enables the resonator 400 to sensitively detect subtle fluctuations in gas density within the resonant cavity 410, providing a more reliable basis for determining the status of the battery 300.

[0067] It is worth mentioning that the first vibration amplifying portion 422 can be configured as, but is not limited to, a first metal sheet.

[0068] In one embodiment, the first vibration amplifying portion 422 is disposed on a side of the vibration exciting body 421 close to the resonant cavity 410 . However, the present design is not limited thereto. In some other embodiments, the first vibration amplifying portion 422 is disposed on a side of the vibration exciting body 421 away from the resonant cavity 410 .

[0069] In one embodiment, the signal pickup unit 430 includes a signal pickup body 431 and a second vibration amplifying unit 432 , and the second vibration amplifying unit 432 is disposed on the signal pickup body 431 .

[0070] Second vibration amplifier 432 amplifies the vibration detected by signal pickup body 431, significantly enhancing the vibration's intensity and detectability. This design enables resonator 400 to sensitively capture subtle fluctuations in gas density within resonant cavity 410, providing a more reliable basis for determining the battery 300's status.

[0071] It is worth mentioning that the second vibration amplifying portion 432 can be configured as, but is not limited to, a second metal sheet.

[0072] In one embodiment, the second vibration amplifying portion 432 is disposed on a side of the signal pickup body 431 close to the resonant cavity 410 .

[0073] In one embodiment, the signal pickup portion 430 is provided with a communication hole 450, through which the resonant cavity 410 communicates with the receiving cavity 210. This allows for a more complete structure of the vibration excitation portion 420, resulting in greater vibrations. This design enables the resonator 400 to sensitively capture subtle fluctuations in gas density within the resonant cavity 410, providing a more reliable basis for determining the status of the battery 300.

[0074] However, the present design is not limited to this. In some other embodiments, the vibration excitation portion 420 is provided with a connecting hole 450, and the resonant cavity 410 is connected to the receiving cavity 210 through the connecting hole; or, the support ring 440 is provided with a connecting hole 450, and the resonant cavity 410 is connected to the receiving cavity 210 through the connecting hole 450.

[0075] There are many different locations for the resonator 400. In one embodiment, the resonator 400 is located above the battery 300. In one example, when the battery 300 experiences thermal runaway, a combustible gas with a density lower than that of air is generated, such as but not limited to hydrogen. Combustible gases with a density lower than that of air rise. The resonator 400 is located above the battery 300 to facilitate the rapid entry of the gas with a density lower than that of air into the resonant cavity 410, thereby changing the gas density in the resonant cavity 410, thereby causing the signal output by the resonator 400 to change. Based on the signal output by the resonator 400, the status of the battery pack 100 can be obtained, and abnormal health status of the battery 300 can be detected in a timely manner. However, the present design is not limited to this. In some other embodiments, the resonant cavity 410 is located between the two ends of the battery 300. Furthermore, in one embodiment, a connecting hole 450 is provided at the lower end of the resonator 400, and the resonant cavity 410 is connected to the receiving cavity 210 through the connecting hole 450.

[0076] Resonant cavity 410 can have various shapes. In one embodiment, resonant cavity 410 is cylindrical. In some examples, cylindrical resonant cavity 410 typically has a higher inherent quality factor (Q value), meaning it loses less energy during resonance and can more efficiently store and transfer energy. A resonant cavity 410 with a high Q value can improve signal stability and sensitivity, making it suitable for high-precision measurement and detection scenarios.

[0077] However, the present design is not limited thereto. In some other embodiments, the resonant cavity 410 may be in the shape of a cuboid.

[0078] In one embodiment, the inner diameter of the resonant cavity 410 ranges from 5 mm to 200 mm. This not only prevents the size of the resonant cavity 410 from being too large, which is beneficial for miniaturizing the battery pack 100, but also prevents the size of the resonant cavity 410 from being too small, which facilitates the processing of the resonant cavity 410. Figure 4 As shown in A.

[0079] In one embodiment, the height of the resonant cavity 410 ranges from 1 mm to 300 mm. This not only prevents the size of the resonant cavity 410 from being too large, which is beneficial for miniaturizing the battery pack 100, but also prevents the size of the resonant cavity 410 from being too small, which facilitates the processing of the resonant cavity 410. Figure 4 As shown in B.

[0080] In one embodiment, the battery pack 100 further includes a spray system 500 disposed in the housing 200. The spray system 500 is connected to the resonator 400 and is configured to spray the battery 300 based on the signal output by the resonator 400. Spraying the battery 300 can lower the temperature of the battery 300, thereby suppressing thermal runaway of the battery 300, thereby reducing the probability of fire and thereby reducing casualties.

[0081] In one embodiment, the spray system 500 includes a spray head 510 and a liquid reservoir 520. The liquid reservoir 520 is used to deliver liquid to the spray head 510. The spray head 510 is disposed in the receiving chamber 210. In one embodiment, the liquid reservoir 520 is disposed in the receiving chamber 210. In one embodiment, the spray head 510 is disposed above the battery 300.

[0082] In one embodiment, the battery pack 100 further includes a battery management system 600, which is respectively connected to the resonator 400, the spray system 500 and the battery 300. The battery management system 600 is used to receive a signal output by the resonator 400 to control the spray system 500.

[0083] Second, embodiments of the present invention provide an electrical device including the aforementioned battery pack 100. This battery pack 100 utilizes all of the technical solutions of all of the aforementioned embodiments and, therefore, possesses at least all of the beneficial effects provided by the technical solutions of the aforementioned embodiments, which are not further detailed here. The electrical device may include, but is not limited to, vehicles, energy storage power supplies, consumer electronics, medical equipment, and smart cities.

[0084] Reference Figure 5In a third aspect, an embodiment of the present invention provides a control method for a battery pack 100. The battery pack 100 includes a housing 200, a battery 300, and a resonator 400. The housing 200 has a receiving chamber 210, and the battery 300 is disposed in the receiving chamber 210. The resonator 400 has a resonant cavity 410, and the resonant cavity 410 is connected to the receiving chamber 210. The resonator 400 is used to vibrate the gas in the resonant cavity 410. The resonator 400 outputs a corresponding signal based on changes in the gas density in the resonant cavity 410. The control method includes:

[0085] S100: Acquire a detection signal of the resonator 400;

[0086] S200: Monitor the battery pack 100 according to the detection signal.

[0087] Since the resonant cavity 410 is connected to the containing cavity 210, once the gas density in the containing cavity 210 changes, the gas density in the resonant cavity 410 will also change accordingly, so that the signal output by the resonator 400 will also change, thereby making it possible to obtain the status of the battery pack 100 more timely, so as to facilitate monitoring of the battery pack 100.

[0088] There are many situations that can cause changes in the gas density within the receiving cavity 210. For example, when the battery pack 100 experiences thermal runaway, the battery 300 releases gas into the receiving cavity 210. Since the resonant cavity 410 is connected to the receiving cavity 210, the gas can enter the resonant cavity 410 more quickly, thereby changing the gas density within the resonant cavity 410, and thus causing the signal output by the resonator 400 to change. Based on the signal output by the resonator 400, the status of the battery pack 100 can be obtained, and abnormalities in the battery pack 100 can be detected in a timely manner. For another example, if the housing 200 is damaged, the receiving cavity 210 is connected to the external environment, and external gas enters the receiving cavity 210, causing the gas density within the receiving cavity to change, thereby changing the gas density within the resonant cavity 410, and thus causing the signal output by the resonator 400 to change. Based on the signal output by the resonator 400, the status of the battery pack 100 can be obtained, and abnormalities in the battery pack 100 can be detected in a timely manner.

[0089] There are many situations that may cause the gas density in the resonant cavity 410 to change, such as thermal runaway of the battery pack 100 or damage to the housing 200, which causes the receiving cavity 210 to communicate with the environment outside the battery pack 100. To reduce the complexity of determining whether the battery pack 100 is in a thermal runaway state, in one embodiment, S200 includes:

[0090] S210 : When the detection signal is different from the first reference signal, it is determined that the battery pack 100 is in a thermal runaway state.

[0091] It is worth mentioning that the first reference signal can be set according to actual conditions. Taking the receiving cavity 210 as an example, the first reference signal is equal to the signal output by the resonant cavity 410 when the gas in the resonator 400 is air.

[0092] Reference Figure 6 In one embodiment, the signal output by the resonator 400 decreases as the gas density in the resonant cavity 410 decreases. S210 includes:

[0093] S211 : When the detection signal is less than the first reference signal, it is determined that the battery pack 100 is in a thermal runaway state.

[0094] Once the gas density generated by thermal runaway of the battery pack 100 is lower than the gas density in the resonant cavity 410, it can be determined that the battery pack 100 is in a thermal runaway state. It can be understood that when the battery pack 100 does not have thermal runaway, the gas density in the resonator 400 is equal to the gas density in the receiving cavity 210, and the detection signal is equal to the first reference signal. Once the gas density generated by thermal runaway of the battery pack 100 is lower than the gas density in the resonant cavity 410, the gas generated by thermal runaway of the battery pack 100 escapes faster and can quickly enter the resonant cavity 410, thereby quickly changing the gas density in the resonant cavity 410, and then quickly changing the detection signal, and then quickly determining that the battery pack 100 is in a thermal runaway state.

[0095] In one example, taking the air in the receiving cavity 210 as an example, the first reference signal is equal to the signal output by the resonant cavity 410 when the gas in the resonator 400 is air. Overcharging, short circuit or other forms of the battery pack 100 will trigger thermal runaway of the battery pack 100. When the battery pack 100 thermally runs away, the battery 300 will produce flammable gas, such as hydrogen. Due to its low density, hydrogen escapes very quickly, which allows hydrogen to enter the resonant cavity 410 relatively quickly, thereby reducing the gas density in the resonant cavity 410, and further causing the detection signal output by the resonator 400 to be less than the first reference signal. In this way, it can be determined that the battery pack 100 is in a thermal runaway state. Taking the piezoelectric resonator 400 as an example, the vibration excitation body 421 is a first piezoelectric piece. The first piezoelectric piece can be, but is not limited to, an Athens ceramic basin. By applying a voltage signal to the first piezoelectric piece, the frequency of the voltage signal is the frequency of the resonant cavity 410, and the frequency of the resonant cavity 410 is f0=KC air, K is a constant related to the collective size of the resonant cavity 410, and Cair is the average sound velocity of the air in the resonant cavity 410 when the resonant cavity 410 is filled with air. Under the excitation of the first piezoelectric plate, the air in the resonant cavity 410 vibrates. At a certain moment, after hydrogen enters the resonant cavity 410, the gas density in the resonant cavity 410 changes, ρ = nρ air + (1-n)ρ hydrogen, where n is the volume fraction of air in the resonant cavity 410. Correspondingly, the gas velocity in the resonant cavity 410 also changes. The frequency change of the current resonant cavity 410 is Δf0=K(CC air )≈nKC air / (2-3n / 2), accordingly, the signal pickup body 431 is a second piezoelectric piece, and the voltage Vout output by the second piezoelectric piece will change, thereby identifying the change in the gas density in the resonant cavity 410.

[0096] Reference Figure 6 In one embodiment, S211 includes:

[0097] S212: When the detection signal is less than the first reference signal and greater than or equal to the second reference signal, determine that the battery pack 100 is in a first thermal runaway state;

[0098] S213: When the detection signal is less than the second reference signal and greater than or equal to the third reference signal, determine that the battery pack 100 is in the second thermal runaway state;

[0099] S214 : When the detection signal is less than the third reference signal, determine that the battery pack 100 is in the third thermal runaway state.

[0100] The thermal runaway state of the battery pack 100 is divided into the first thermal runaway state, the second thermal runaway state, and the third thermal runaway state through the detection signal, which can more accurately reflect the abnormality level of the battery pack 100. This hierarchical warning mechanism not only provides richer status information, but also can take corresponding countermeasures according to different thermal runaway stages. An early warning can be issued in the early stage of thermal runaway (such as the first thermal runaway state), reminding the system or operator to take measures (such as cooling, power off, etc.), thereby effectively delaying or preventing the further development of thermal runaway and reducing the risk of accidents. Different degrees of emergency measures can be taken according to different thermal runaway states. For example, in the first thermal runaway state, it may only be necessary to reduce the discharge power of the battery pack 100; while in the third thermal runaway state, it is necessary to control the spray system 500 to open. This hierarchical response strategy can optimize resource allocation and avoid excessive or insufficient intervention. By promptly detecting and taking measures in the first thermal runaway state, more time can be purchased for subsequent safety processing and the severity of the accident can be reduced.

[0101] Reference Figure 7 In one embodiment, S200 includes:

[0102] S220: Obtaining the gas concentration of the gas to be detected according to the detection signal;

[0103] S221: When the gas concentration is less than the first reference concentration and greater than or equal to the second reference concentration, determine that the battery pack 100 is in a first thermal runaway state;

[0104] S222: When the gas concentration is less than the second reference concentration and greater than or equal to the third reference concentration, determine that the battery pack 100 is in a second thermal runaway state;

[0105] S223 : When the gas concentration is less than the third reference concentration, determine that the battery pack 100 is in the third thermal runaway state.

[0106] The thermal runaway state of the battery pack 100 is divided into the first, second, and third thermal runaway states based on gas concentration, which can more accurately reflect the degree of abnormality of the battery pack 100. This hierarchical warning mechanism not only provides richer status information, but also enables corresponding response measures to be taken according to different thermal runaway stages. An early warning can be issued in the early stages of thermal runaway (such as the first thermal runaway state), reminding the system or operator to take measures (such as cooling, power off, etc.), thereby effectively delaying or preventing further development of thermal runaway and reducing the risk of accidents. Different levels of emergency measures can be taken depending on the different thermal runaway states. For example, in the first thermal runaway state, it may only be necessary to reduce the discharge power of the battery pack 100; while in the third thermal runaway state, it is necessary to control the spray system 500 to open. This hierarchical response strategy can optimize resource allocation and avoid excessive or insufficient intervention. By promptly detecting and taking measures in the first thermal runaway state, more time can be purchased for subsequent safety processing and the severity of the accident can be reduced.

[0107] For example, overcharging, short circuiting, or other conditions may trigger thermal runaway of the battery pack 100. When the battery pack 100 experiences thermal runaway, the battery 300 may produce flammable gases, such as hydrogen. Due to its low density, hydrogen escapes very quickly, allowing it to enter the resonant cavity 410 relatively quickly. This reduces the gas density within the resonant cavity 410, thus confirming that the battery pack 100 is in thermal runaway. As the duration of the battery pack 100's thermal runaway increases, the battery 300 produces more and more hydrogen, which reduces the concentration of the gas to be detected. This may cause the battery pack 100 to enter the first thermal runaway state, the second thermal runaway state, and the third thermal runaway state, in sequence.

[0108] In one embodiment, the battery pack 100 further includes a spray system 500 disposed in the housing 200 , and the spray system 500 is connected to the resonator 400 ;

[0109] The control method also includes:

[0110] S310: When the battery pack 100 is in the first thermal runaway state, reducing the discharge power of the battery pack 100;

[0111] S320: When the battery pack 100 is in the second thermal runaway state, stop charging and discharging the battery pack 100;

[0112] S330 : When the battery pack 100 is in the third thermal runaway state, the spray system 500 is controlled to be turned on.

[0113] This graded response mechanism can accurately respond to thermal runaway at different stages and reduce the occurrence of excessive or insufficient intervention.

[0114] In this way, by taking different measures according to the severity of the thermal runaway, overly radical measures (such as direct spraying) are avoided in the early stages. For example, in the first thermal runaway state, reducing the discharge power can not only effectively control the further development of the thermal runaway, but also will not cause too much impact on the normal operation of the battery pack 100, while reducing the unnecessary use of resources such as the sprinkler system 500. In addition, the sprinkler system 500 usually consumes a certain amount of fire extinguishing medium and energy, and may have a certain impact on the subsequent use of the battery pack 100. Through graded response, the sprinkler system 500 is used as a last resort to ensure that resources are used when they are most needed to avoid waste.

[0115] The first thermal runaway state reduces the discharge power, which can effectively reduce the heat generation inside the battery 300 and prevent the temperature of the battery 300 from further increasing, thereby reducing thermal damage to the internal structure and materials of the battery 300 and extending the life of the battery 300.

[0116] Stopping charging and discharging in the second thermal runaway state can prevent the battery 300 from continuing to operate at high temperatures, avoid exacerbating thermal runaway due to problems such as overcharging, overdischarging or short circuit, and further reduce the risk of damage to the battery 300.

[0117] The spray system 500 is activated only in more serious situations, avoiding spraying the battery pack 100 in the early stage of thermal runaway, thereby reducing potential corrosion or damage to the battery pack 100 by the fire extinguishing medium, which is beneficial to the subsequent repair and use of the battery pack 100.

[0118] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A battery pack, characterized in that: include A housing is provided with a receiving cavity; a battery, disposed in the receiving cavity; and The resonator is provided with a resonant cavity, the resonant cavity is connected to the receiving cavity, the resonator outputs a corresponding signal according to the change of gas density in the resonant cavity, and the signal output by the resonator is used to monitor the battery pack.

2. The battery pack according to claim 1, wherein: The resonator is arranged in the receiving cavity; And / or, the resonator is configured as a piezoelectric resonator, an electrostatic resonator or a capacitive resonator.

3. The battery pack according to claim 1, wherein: The resonator includes a vibration excitation part, a signal pickup part and a support ring. The vibration excitation part and the signal pickup part are respectively arranged at both ends of the support ring. The vibration excitation part, the signal pickup part and the support ring jointly enclose the resonant cavity. The vibration excitation part is used to generate vibration to drive the signal pickup part to generate vibration. The signal pickup part is used to detect the vibration and convert it into a signal output by the resonator.

4. The battery pack according to claim 3, wherein: The vibration excitation part includes a vibration excitation body and a first vibration amplifying part, and the first vibration amplifying part is provided on the vibration excitation body; And / or, the signal pickup unit includes a signal pickup body and a second vibration amplifying unit, and the second vibration amplifying unit is provided on the signal pickup body; And / or, the signal pickup portion is provided with a communication hole, and the resonant cavity is connected to the receiving cavity through the communication hole.

5. The battery pack according to claim 1, wherein: The resonator is arranged above the battery.

6. The battery pack according to claim 5, characterized in that: The resonant cavity is cylindrical, and the inner diameter of the resonant cavity ranges from 5 mm to 200 mm; And / or, the height of the resonant cavity ranges from 1 mm to 300 mm.

7. The battery pack according to any one of claims 1 to 6, characterized in that: The battery pack further includes a spray system provided on the shell, wherein the spray system is connected to the resonator and is used to spray the battery according to a signal output by the resonator.

8. An electrical device, characterized in that: Comprising the battery pack according to any one of claims 1 to 7.

9. A method for controlling a battery pack, the battery pack comprising a housing, a battery, and a resonator, the housing having a receiving chamber, the battery being disposed in the receiving chamber, the resonator having a resonant cavity, the resonant cavity being in communication with the receiving chamber, the resonator being configured to vibrate gas within the resonant cavity, the resonator outputting a corresponding signal based on changes in gas density within the resonator, characterized in that: The control method includes: obtaining a detection signal of the resonator; The battery pack is monitored according to the detection signal.

10. The battery pack control method according to claim 9, characterized in that: Monitoring the status of the battery pack according to the detection signal includes: When the detection signal is different from the first reference signal, it is determined that the battery pack is in a thermal runaway state.

11. The battery pack control method according to claim 10, characterized in that: The signal output by the resonator decreases as the density of the gas in the resonant cavity decreases; When the detection signal is different from the first reference signal, determining that the battery pack is in a thermal runaway state includes: When the detection signal is less than the first reference signal, it is determined that the battery pack is in a thermal runaway state.

12. The battery pack control method according to claim 11, characterized in that: When the detection signal is less than the first reference signal, determining that the battery pack is in a thermal runaway state includes: When the detection signal is less than the first reference signal and greater than or equal to a second reference signal, determining that the battery pack is in a first thermal runaway state; When the detection signal is less than the second reference signal and greater than or equal to a third reference signal, determining that the battery pack is in a second thermal runaway state; When the detection signal is less than the third reference signal, it is determined that the battery pack is in a third thermal runaway state.

13. The battery pack control method according to claim 9, characterized in that: Monitoring the battery pack according to the detection signal includes: Acquiring the gas concentration of the gas to be detected according to the detection signal; When the gas concentration is less than a first reference concentration and greater than or equal to a second reference concentration, determining that the battery pack is in a first thermal runaway state; When the gas concentration is less than the second reference concentration and greater than or equal to a third reference concentration, determining that the battery pack is in a second thermal runaway state; When the gas concentration is less than the third reference concentration, it is determined that the battery pack is in a third thermal runaway state.

14. The battery pack control method according to claim 12 or 13, characterized in that: The battery pack further includes a spray system provided on the housing, the spray system being connected to the resonator; The control method further includes: When the battery pack is in the first thermal runaway state, reducing the discharge power of the battery pack; When the battery pack is in the second thermal runaway state, stopping charging and discharging of the battery pack; When the battery pack is in the third thermal runaway state, the spray system is controlled to turn on.

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