Battery pack
By introducing current guides and alarm units into the battery pack, dual audible and visual warnings are provided in the early stages of battery thermal runaway, and the pressure relief channel is kept open during high-temperature stages. This solves the problem of insufficient external warnings during battery thermal runaway and improves safety and controllability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-07
- Publication Date
- 2026-04-07
AI Technical Summary
In the event of thermal runaway of existing batteries, there is a lack of effective warning devices inside and outside the vehicle, which makes it impossible for surrounding road users to identify the danger in time, increasing the risk of secondary accidents.
Design a battery pack that includes a flow guide and an alarm unit. The high-temperature airflow generates a dual warning of sound and light by passing through the turbulence-generating holes and flow channels in the flow guide. The flow guide adjusts the gas emission direction to vertical downward to avoid horizontal diffusion, and the buckle automatically disengages at high temperatures to ensure that the pressure relief channel is unobstructed.
In the early stages of battery thermal runaway, a dual warning system of sound and light can alert those in the vicinity, reducing the risk of secondary accidents. During the high-temperature phase, it is also important to ensure that the pressure relief channel remains unobstructed to reduce the threat of flame spread.
Smart Images
Figure CN224096736U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery pack fault alarm technology, and in particular to a battery pack. Background Technology
[0002] With the rapid expansion of the number of new energy vehicles, the reliability of power battery systems has become increasingly prominent, especially with a significant upward trend in vehicle spontaneous combustion accidents caused by battery thermal runaway.
[0003] In the initial stages of battery thermal runaway, the system only provides warnings through the vehicle's instrument panel. At this time, irreversible chemical reactions have already occurred inside the battery pack, but there is no obvious smoke or flame on the outside. Other road users cannot perceive the danger through visual observation (before smoke / fire) nor receive warnings through the vehicle's external warning system, causing pedestrians and adjacent vehicles in the danger zone to be unable to avoid danger in time, which can easily lead to secondary collisions. Utility Model Content
[0004] In view of the shortcomings of the prior art described above, the purpose of this utility model is to propose a battery pack that can alert people in the vicinity when the battery thermal runaway.
[0005] To achieve the above and other related objectives, this utility model provides a battery pack, comprising:
[0006] Box;
[0007] An explosion-proof valve is installed in the enclosure, and the explosion-proof valve includes a pressure relief port;
[0008] A flow guide, which is connected to the pressure relief port, and the flow guide includes an exhaust port facing the outside atmosphere;
[0009] An alarm unit is disposed within the flow guide. The alarm unit includes a turbulence sound-emitting hole and a flow channel, the flow channel connecting the turbulence sound-emitting hole and the pressure relief port.
[0010] In an optional embodiment of this utility model, the cross-sectional area of the flow channel gradually decreases from the air inlet end to the air outlet end.
[0011] In an optional embodiment of this utility model, the ratio of the cross-sectional area of the air inlet end to the cross-sectional area of the air outlet end of the flow channel is 2:1 to 100:1.
[0012] In an optional embodiment of this utility model, the explosion-proof valve is disposed on the side wall of the housing, and the exhaust port is disposed facing downward.
[0013] In an optional embodiment of this utility model, the alarm unit is connected to the guide member via a snap-fit part. The snap-fit part is configured such that when a high-temperature airflow passes through the snap-fit part, the snap-fit part can be disconnected to allow the alarm unit to detach from the guide member through the exhaust port.
[0014] In an optional embodiment of this utility model, the alarm unit is located at the position of minimum cross-sectional area inside the flow guide.
[0015] In an optional embodiment of the present invention, the buckle portion is made of a first material, which is configured to melt at high temperatures.
[0016] In an optional embodiment of this invention, the remaining parts of the alarm unit are also made of the first material.
[0017] In an optional embodiment of the present invention, the alarm unit further includes a second material, which is configured to generate smoke at high temperatures.
[0018] In an optional embodiment of this utility model, the alarm unit includes a resonant cavity, and the turbulence-generating hole is located between the resonant cavity and the flow channel.
[0019] In an optional embodiment of this utility model, the turbulence-generating hole is arranged in a horizontal direction, and a through hole is provided on the flow guide corresponding to the position of the turbulence-generating hole.
[0020] In an optional embodiment of this utility model, one side of the flow guide is open, and the open side is fitted onto the housing to form a chamber. The pressure relief port is located inside the chamber, and an exhaust channel communicating with the exhaust port is provided below the chamber. The alarm unit is located inside the exhaust channel.
[0021] In an optional embodiment of this utility model, the cross-sectional area of the exhaust channel gradually increases from the end away from the exhaust port to the end closer to the exhaust port.
[0022] In an optional embodiment of this utility model, the ratio of the cross-sectional area of the exhaust port to the cross-sectional area of the end of the exhaust channel away from the exhaust port is 2:1 to 100:1.
[0023] In an optional embodiment of this utility model, the flow guide is a heat-resistant metal component.
[0024] In an optional embodiment of this utility model, the alarm unit is integrated with the flow guide or the explosion-proof valve (20).
[0025] The technical advantage of this invention lies in its ability to provide a dual warning system—both audible and visual—by linking the turbulence-generating sound hole within the flow guide with the pressure relief port. This system utilizes the whistling sound generated when high-pressure gas flows through the channel during the initial stage of battery thermal runaway. This design requires no alteration to the enclosure or explosion-proof valve structure, retaining the original pressure relief function while actively emitting high-frequency alarm sound waves through gas flow energy conversion, effectively solving the problem of delayed external environmental warnings in traditional solutions. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a disassembly diagram of the battery pack in one embodiment of the present invention;
[0028] Figure 2 This is a schematic diagram of the alarm unit of the battery pack in one embodiment of the present invention;
[0029] Figure 3 for Figure 2 The AA section view in the figure shows the direction of airflow indicated by straight arrows.
[0030] Figure 4 This is a schematic diagram of the upper end of the alarm unit of the battery pack in one embodiment of the present invention;
[0031] Figure 5 for Figure 4 BB section view;
[0032] Figure 6 This is a schematic diagram of the structure of the flow guide of the battery pack in one embodiment of the present invention.
[0033] Explanation of reference numerals in the attached drawings: 10, housing; 20, explosion-proof valve; 21, pressure relief port; 30, flow guide; 31, exhaust port; 32, through hole; 33, exhaust channel; 34, flange; 40, alarm unit; 41, sound hole; 42, flow channel; 43, resonance cavity; 44, snap-fit part. Detailed Implementation
[0034] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.
[0035] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.
[0036] With the rapid development of new energy vehicles globally, the market is experiencing explosive growth due to their significant energy-saving and emission-reduction advantages and high level of intelligence. However, along with this growth, the failure rate of battery packs is also rising, particularly posing serious challenges to the sealing and safety of battery packs. How to detect battery pack failures early and effectively reduce the severity of accidents has become a critical issue that the industry urgently needs to address.
[0037] Current industry-standard battery safety warning technologies primarily rely on the built-in sensor network of the BMS (Battery Management System) to provide thermal runaway warnings by monitoring parameters such as voltage, temperature, and gas concentration in real time. When an anomaly is detected, an alert is issued to the driver via dashboard warning lights and a buzzer. For warnings about external environmental conditions, existing technologies rely solely on the vehicle's standard hazard lights, with triggering criteria primarily based on collision sensor signals.
[0038] During the initial gas release phase of thermal runaway, although the BMS can trigger in-vehicle audible and visual alarms, the battery pack has not yet shown visible smoke or flame characteristics. Due to the lack of effective external warning devices, surrounding road users (including pedestrians and adjacent vehicles) cannot obtain information about the hazard, resulting in a high rate of secondary accidents.
[0039] Existing pressure relief valves employ a one-way mechanical structure, lacking the ability to actively control the high-temperature jet stream (temperature gradient 800-1200℃) generated by thermal runaway. Experimental data shows that such uncontrolled jet streams can penetrate steel plates, and the incandescent particles they carry have a large diffusion radius, sufficient to ignite the fuel systems of adjacent vehicles or flammable materials on the road. More seriously, when the jet stream comes into contact with the vehicle's interior materials, it will trigger a chain reaction, accelerating the spread of the fire.
[0040] Traditional battery pack layouts place the pressure relief valve on the side, resulting in a horizontally diffused high-temperature jet. This lateral jet creates an impact angle with vehicles in adjacent lanes, directly threatening the vehicle's fuel tank area. In evacuation scenarios, the horizontal jet direction dangerously intersects with passenger escape routes, causing the interior temperature to spike far beyond the limits of human skin tolerance. This disordered energy release significantly increases the unpredictability of accident consequences.
[0041] To achieve the above objectives and other related objectives, such as Figures 1-6 As shown, this utility model proposes a battery pack, including a housing 10, an explosion-proof valve 20, a flow guide 30, and an alarm unit 40 as an example. Figure 1 Only a portion of the housing 10 is shown. Those skilled in the art will understand that the housing 10 may refer to the entire outer envelope of the battery pack and may have various shapes.
[0042] Explosion-proof valve 20 is installed in housing 10, for example... Figure 1 As shown, the explosion-proof valve 20, including a pressure relief port 21, is installed on the side wall of the housing 10. When the internal pressure of the battery pack is too high, the explosion-proof valve 20 can open to release the pressure and prevent an explosion due to excessive pressure. The pressure relief port 21 is part of the explosion-proof valve 20 and is used to guide the high-pressure gas out.
[0043] The flow guide 30 is connected to the pressure relief port 21, and the flow guide 30 includes an exhaust port 31 facing the outside atmosphere. The flow guide 30 is directly connected to the pressure relief port 21 of the explosion-proof valve 20, forming a gas emission path from the inside of the battery pack to the outside.
[0044] The flow guide 30 is made of heat-resistant metal (such as 310S stainless steel, nickel-based alloy, etc.). The heat-resistant metal material can ensure that the flow guide 30 maintains stable performance under high-temperature airflow and prevents the flow guide 30 from melting due to high-temperature airflow in the event of thermal runaway, thereby affecting the flow guiding effect.
[0045] An alarm unit 40 is disposed within the airflow guide 30. The function of the alarm unit 40 is to issue an alarm when the battery pack malfunctions, alerting nearby personnel to safety. The alarm unit 40 includes a turbulence-generating hole 41 and a flow channel 42, with the flow channel 42 connecting the turbulence-generating hole 41 and the pressure relief port 21. The turbulence-generating hole 41 is designed to generate airflow disturbance, which transfers energy through the flow channel 42, thereby emitting a sound wave signal. When the battery pack experiences thermal runaway, in addition to issuing an alarm to the driver via the audible and visual alarm system, the alarm unit 40 through the airflow guide 30 can also emit a sound wave alarm to the external environment, alerting nearby personnel and thus reducing secondary accidents caused by battery safety issues.
[0046] like Figure 5As shown, the inner diameter of the turbulence-generating orifice 41 is smaller than the outer diameter. The asymmetric flow channel formed by the difference in diameter between the inner and outer sides of the expanding orifice causes abrupt changes in the velocity gradient when the airflow passes through, resulting in shear layer separation at the orifice inlet. After the shear layer becomes unstable, it forms a periodic vortex structure, providing an energy source for sound wave generation. During the expansion of the airflow in the expanding section, the momentum exchange between the boundary layer and the core flow intensifies, and the jet shearing effect at the edge of the orifice plate is significantly enhanced. This disturbance is geometrically amplified by the expanding structure, forming a self-sustaining pressure pulsation, which promotes the improvement of sound energy radiation efficiency. When the airflow flows through the sharp edge of the expanding orifice, the periodically detached vortices form a Karman vortex street-like structure. The vortex shedding frequency is strongly correlated with the geometric parameters of the expanding orifice (orifice gradient, flow channel curvature), and the characteristic frequency can be adjusted to the frequency band sensitive to the human ear through design.
[0047] like Figure 3 , 5 As shown, the alarm unit 40 includes a resonant cavity 43, a semi-enclosed space that allows sound waves entering through its inlet to reflect back and forth within the space, thereby enhancing the amplitude of the sound waves and amplifying the sound. This design makes the alarm system more noticeable in noisy environments. A turbulence-generating hole 41 is located between the resonant cavity 43 and the flow channel 42. Its design causes disturbances when fluid (typically gas) flows through it, and these disturbances generate sound waves within the resonant cavity 43. The size, shape, and position of the turbulence-generating hole 41 can be specifically designed to produce specific acoustic effects. The flow channel 42 connects the turbulence-generating hole 41 and the resonant cavity 43, guiding gas flow not only through the turbulence-generating hole 41 but also through the resonant cavity 43. This design is similar to a whistle, where the airflow generated when blowing creates disturbances at specific locations, thus producing sound. In this embodiment, this structure is used in the alarm system of a battery pack to produce a clear and audible alarm sound.
[0048] like Figure 5 As shown, the cross-sectional area of the flow channel 42 gradually decreases from the inlet to the outlet. This gradual decrease in cross-sectional area forms a converging flow channel. When the gas flows through this converging section, it is constrained, and the flow velocity increases significantly with the decrease in cross-sectional area, forming a high-speed jet. The combination of the converging flow channel and the turbulence-generating hole 41 forms a whistling-like structure. The gradient change in the cross-sectional area of the flow channel 42 regulates the airflow vibration frequency. Combined with the geometric characteristics of the turbulence-generating hole 41 (such as edge sharpness and aperture ratio), the sound wave frequency is locked to a specific frequency band sensitive to the human ear, emitting an alarm sound of 200Hz to 2000Hz.
[0049] In an optional embodiment of this invention, the ratio of the inlet cross-sectional area to the outlet cross-sectional area of the flow channel 42 is 2:1 to 100:1. This range ensures that the gas flow rate increases to a critical threshold, triggering a stable turbulent state and providing continuous energy input for sound wave generation. The lower limit (2:1) guarantees basic flow rate gain, while the upper limit (100:1) prevents excessive contraction of the flow channel 42, which could lead to airflow blockage or insufficient structural strength. Within this range, the gas kinetic energy is maximized to be converted into acoustic energy, significantly improving the alarm sound intensity. By adjusting the ratio to adapt to different battery pack depressurization rates, it ensures effective alarm triggering from low-speed leakage to severe thermal runaway scenarios.
[0050] like Figure 1 As shown, the explosion-proof valve 20 is located on the side wall of the housing 10, but the exhaust port 31 is forcibly adjusted to a vertically downward direction through the bend design of the internal flow channel of the guide component 30. The inner wall of the guide component 30 adopts a high-temperature resistant guide surface to guide the thermal runaway gas to form a downward jet. The high-temperature gas directly impacts the ground, using the ground as a natural thermal barrier to block the horizontal diffusion path and avoid threatening the fuel tanks of vehicles in adjacent lanes or densely populated pedestrian areas. The vertical downward jet forcibly changes the traditional lateral disordered diffusion mode, and the gas kinetic energy is quickly dissipated through ground contact, significantly reducing the risk of secondary ignition of the flame. The downward design of the exhaust port 31 spatially decouples the jet from the horizontal escape path of the occupants. When personnel evacuate from the vehicle, the high-temperature gas is confined to the bottom area of the vehicle, forming a vertical isolation from the occupant activity space.
[0051] like Figure 2 , 3 As shown in Figure 5, the alarm unit 40 is connected to the flow guide 30 via a snap-fit part 44. The flow guide 30 has a snap-fit hole on its inner side, and the snap-fit part 44 is inserted into the snap-fit hole to form a snap-fit engagement. The snap-fit part 44 is configured such that when a high-temperature airflow passes through the snap-fit part 44, the connection can be broken, allowing the alarm unit 40 to detach from the flow guide 30 through the exhaust port 31. The alarm unit 40 forms a mechanical connection with the flow guide 30 via the snap-fit part 44. The material strength and structural geometry of the snap-fit part 44 are optimized to maintain a stable connection under normal operating conditions, while automatically failing under the impact of high-temperature, high-pressure airflow generated by thermal runaway.
[0052] The retaining force of the latching part 44 is 20-200N. When the material of the latching part 44 softens due to high temperature or the shear force generated by the high-pressure airflow exceeds the connection retaining force, the latching part 44 automatically disconnects, ensuring that the alarm unit 40 is quickly dislodged. After the alarm unit 40 is dislodged, the internal channel of the guide member 30 is completely released, avoiding obstruction of the pressure relief path by structural residues and ensuring the pressure relief efficiency of the explosion-proof valve 20.
[0053] The snap-fit part 44 can simultaneously withstand airflow impact and thermal load in high-temperature environments through the synergistic effect of a preset physical weakening structure (such as a neck or groove) and the material's thermal sensitivity. The weakened structural parts fracture preferentially under stress concentration, while the high-temperature weakening material (such as thermoplastics containing flame retardants) softens, reducing connection strength. The physical weakening structure and the material's thermal sensitivity provide dual protection, ensuring reliable disconnection even under complex conditions (such as high temperature but insufficient air pressure, or high pressure but below-standard temperature). The weakened structure absorbs and disperses impact energy during fracture, reducing the risk of damage to surrounding structures from the depressurized airflow.
[0054] The latching part 44 can also be made of a first material, which is configured to melt at high temperatures. The latching part 44 uses a thermoplastic plastic with added flame retardants as the first material, maintaining sufficient mechanical strength at room temperature to secure the alarm unit 40. When the ambient temperature reaches the material's melting point, the plastic softens or melts, causing the latching part 44 to fail. Specifically, the first material can be plastic with added flame retardants, such as polybrominated diphenyl ethers (PBDEs). The addition of flame retardants inhibits combustion reactions at high temperatures and reduces the material's melt viscosity, accelerating the disintegration process of the latching part 44. The flame retardant prevents the fire from spreading and also promotes rapid detachment of the latching part 44 by reducing melt strength. Specific flame retardants (such as PBDEs) decompose within a controllable temperature range, avoiding the generation of toxic gases that could endanger personnel safety.
[0055] In the early stages of thermal runaway, the internal pressure of the battery pack surges rapidly. When the high-speed airflow released from the pressure relief port 21 flows through the turbulence-generating holes 41 within the guide vane 30, the interaction between the airflow velocity and the geometry of the holes generates periodic vortex shedding and pressure fluctuations. These pressure fluctuations are amplified by the acoustic resonant cavity 43, forming a high-frequency whistling sound. This sharp whistling sound can be triggered before the thermal runaway spreads to the open flame stage, buying crucial time for personnel evacuation and emergency response. The sound wave energy originates entirely from gas kinetic energy, without relying on onboard power or sensors, ensuring reliable alarm function even when the battery system is powered off.
[0056] As thermal runaway intensifies, the temperature of the depressurized airflow rises to the material response threshold (e.g., ≥105℃), causing the heat-sensitive material (e.g., flame-retardant modified plastic) used in the latching part 44 to soften or melt, resulting in a sharp drop in the mechanical connection strength. At this point, the impact force of the high-temperature, high-speed airflow and the weakening of the material work together to cause the alarm unit 40 to automatically detach from the guide member 30.
[0057] After the alarm unit 40 detaches, the internal channel of the guide component 30 is fully open, avoiding obstruction of pressure relief due to structural residue and ensuring rapid discharge of high-temperature and high-pressure gas.
[0058] The thermal runaway process is divided into two stages: the initial high-speed airflow stage (centered on acoustic alarms) and the high-temperature, high-pressure airflow stage (centered on pressure relief). After completing its initial warning task, the alarm unit 40 actively deactivates via a high-temperature-triggered physical tripping mechanism to avoid interfering with subsequent pressure relief. The alarm and pressure relief functions operate in a time-sharing manner, without interfering with each other, thus improving system reliability.
[0059] In the initial stage of thermal runaway, the airflow at the pressure relief port 21 is a high-speed airflow. The high-speed airflow will emit a sharp whistling sound when it passes through the turbulence sound hole 41. Subsequently, as thermal runaway progresses, the high-speed airflow becomes a high-temperature high-speed airflow (high temperature can specifically refer to ≥105℃). Under the action of high temperature, the alarm unit 40 can be detached.
[0060] In an optional embodiment of this invention, the alarm unit 40 is located at the minimum cross-sectional area of the internal flow channel of the guide member 30. Utilizing the principle of fluid continuity, the gas velocity reaches its peak when flowing through this location. In the initial stage of thermal runaway (low-temperature high-speed stage), the high flow velocity at the minimum cross-sectional area preferentially triggers the alarm. As the temperature rises, the high-temperature airflow softens the material of the latching part 44, and after the alarm unit 40 detaches, the minimum cross-sectional area transforms into an unobstructed pressure relief channel, avoiding increased pressure relief resistance due to structural residue.
[0061] In an optional embodiment of this invention, the remaining parts of the alarm unit 40 are also made of the first material. The thermal properties of the material permeate the entire alarm unit 40, ensuring that it softens or melts synchronously under high-temperature conditions. All components lose mechanical strength synchronously due to the uniformity of the material, avoiding local residue blockage of the pressure relief channel. After the unit as a whole melts, its fluidity increases, allowing it to detach from the guide member 30 in a liquid or softened state, reducing the generation of solid fragments. At the same time, after the alarm function is completed, the unit quickly exits the pressure relief path, ensuring that the high-temperature airflow is discharged without obstruction.
[0062] In an optional embodiment of this invention, a second material is added to the constituent materials of the alarm unit 40. This second material is configured to generate smoke at high temperatures. The thermal decomposition temperature (≥105℃) of the second material matches the softening temperature of the first material, ensuring that the smoke release and the detachment of the alarm unit 40 are synchronized. The second material can be the same as the first material. The second material can be a compound such as copper or iron, used to generate red smoke. The red smoke, combined with a high-frequency whistling sound, overcomes environmental noise or visual obstacles (such as dense fog or nighttime scenes), improving the warning recognition rate. The smoke can penetrate visual obstacles (such as vehicle smoke), and the sound waves can cover auditory blind spots, achieving a three-dimensional warning. Initially, the acoustic alarm attracts attention; during the high-temperature stage, the smoke marks dangerous areas, forming a phased warning strategy. Simultaneously, smoke generation relies entirely on the heat energy released during thermal runaway, requiring no external energy source or chemical agents.
[0063] In an optional embodiment of this invention, the turbulence-generating hole 41 is oriented horizontally, with the main radiation direction of the sound waves aligned with the positions of adjacent traffic participants (pedestrians, adjacent vehicles), thereby increasing the sound pressure level in the target area. Horizontal radiation reduces acoustic interference between ground-reflected sound waves and the vehicle chassis structure, enhancing the visibility of warning sounds. Other traffic participants are typically located beside the battery pack. The battery pack is usually located in the middle or rear of the vehicle chassis, with the adjacent area being a high-frequency activity zone for pedestrians and non-motorized vehicles. Horizontal sound waves penetrate directly through the through-hole 32 of the guide member 30 and diffuse outwards.
[0064] A through hole 32 is provided on the flow guide 30 at the position corresponding to the turbulence sound-emitting hole 41. The through hole 32 can avoid the turbulence sound-emitting hole 41. The through hole 32 avoidance design ensures that the sound wave radiation of the turbulence sound-emitting hole 41 is not affected by the diffraction of the edge of the through hole 32, and maintains the directionality of the main lobe of the sound wave.
[0065] like Figure 1 As shown, one side of the flow guide 30 is open, and the flow guide 30 is fitted to the housing 10 through the open side to form a sealed chamber structure. The pressure relief port 21 is located inside the chamber, causing the thermal runaway gas to first accumulate in the chamber and then enter the lower exhaust channel 33. The alarm unit 40 is built into the exhaust channel 33 and is directly exposed to the airflow path. The chamber structure guides the initially disordered pressure relief gas to the exhaust channel 33, avoiding energy loss caused by airflow dispersion and improving the triggering efficiency of the alarm unit 40.
[0066] like Figure 6 As shown, the open side of the flow guide 30 is provided with a flange 34, which is fastened to the housing 10 by bolts to form a detachable modular component. The bolt connection allows the flow guide 30 or the alarm unit 40 to be replaced without damaging the structure of the housing 10, greatly reducing maintenance complexity; a high-temperature resistant sealing gasket can be provided on the contact surface between the flange 34 and the housing 10 to ensure the airtightness of the chamber and prevent gas leakage from weakening the alarm function. The exhaust channel 33, as the only path connecting the chamber to the outside, has the dual functions of gas guidance and alarm triggering. The alarm unit 40 is located at a key cross-sectional area position within the channel, directly sensing the airflow status.
[0067] like Figure 6 As shown, the exhaust channel 33 adopts a geometric configuration with a gradually increasing cross-sectional area from the inlet end (away from the exhaust port 31) to the outlet end (closer to the exhaust port 31), forming a gradually expanding flow channel. When the gas flows through the expanding section, the flow velocity decreases due to the increased cross-sectional area. During this velocity reduction process, some of the kinetic energy is converted into heat energy through turbulent friction and dissipated to the external environment through the channel wall, significantly reducing the temperature of the injected gas. The expanding structure promotes lateral gas diffusion, reduces the impact range of concentrated gas injection, and lowers the risk of the high-temperature exhaust flame igniting surrounding objects.
[0068] The cross-sectional area ratio of the inlet to outlet of exhaust channel 33 is adjustable from 2:1 to 100:1, allowing for matching of gas flow and pressure characteristics under different thermal runaway scenarios through geometric parameters. A smaller ratio (2:1) is suitable for mild pressure relief requirements, ensuring basic heat dissipation performance; a larger ratio (100:1) is suitable for severe thermal runaway, maximizing kinetic energy dissipation and temperature decay. The ratio range setting avoids excessively thin channel walls or stress concentration caused by extreme gradual expansion, ensuring mechanical stability under high temperature and high pressure.
[0069] The geometric parameters of the gradually expanding flow channel can be optimized for battery pack layouts in different vehicle models, adapting to varying requirements such as chassis ground clearance and road conditions. The gradually expanding flow channel can be integrally molded using a single mold, and adjustments to the cross-sectional area ratio only require modification of the flow channel draft angle, seamlessly integrating with existing guide component 30 production processes.
[0070] In an optional embodiment of this utility model, the alarm unit 40 and the flow guide 30 are integrated into a compact module. The turbulence-generating hole 41, resonant cavity 43, and other structures of the alarm unit 40 are seamlessly connected to the flow channel 42, exhaust port 31, and other components of the flow guide 30. This integrated design eliminates the connection gaps of separate components, avoiding the risk of high-temperature gas leakage or structural loosening. The alarm unit 40 is embedded inside the cavity of the flow guide 30, sharing the installation interface and support structure of the flow guide 30, without requiring additional battery pack space. The modular design allows for complete replacement of the flow guide 30-alarm unit 40 assembly, simplifying the maintenance process.
[0071] In another optional embodiment of this utility model, the alarm unit 40 is integrated into the body of the explosion-proof valve 20. The alarm function is directly triggered by the airflow impact or mechanical action when the explosion-proof valve 20 is opened, for example, by linking the valve plate displacement with the sound-generating mechanism. The alarm is activated synchronously the moment the explosion-proof valve 20 is opened, without waiting for the airflow to be transmitted to the independent alarm unit 40, thus shortening the warning time.
[0072] In summary, through the coordinated design of the flow guide 30 and the alarm unit 40, full-cycle safety protection against thermal runaway is achieved without altering the main structure of the battery pack housing 10 and the explosion-proof valve 20. In the initial stage of thermal runaway, when the high-pressure airflow passes through the gradually narrowing channel within the flow guide 30, high-frequency sound waves are generated through the gradually expanding turbulence-generating holes 41, actively issuing acoustic warnings to the external environment. This overcomes the limitations of traditional solutions that rely on in-vehicle instrument alarms, effectively solving the problem that surrounding road users cannot perceive the danger in time. Simultaneously, the flow guide 30, through its channel deflection design, adjusts the traditional lateral pressure relief direction to a vertical downward direction, utilizing the ground as a natural thermal barrier to block the horizontal diffusion path of high-temperature gas, preventing the ignition of adjacent vehicles or threats to evacuation routes. When thermal runaway enters the high-temperature stage, the latch 44 automatically detaches based on the melting characteristics of the heat-sensitive material or the mechanical failure mechanism of the weakened structure, ensuring unobstructed pressure relief channels. Furthermore, through multi-stage energy dissipation mechanisms such as airflow kinetic energy conversion to acoustic energy, turbulent mixing, and ground contact, the jet temperature and ignition risk are significantly reduced. In addition, the modular integrated design enables the alarm unit 40 to have smoke warning, resonance amplification and quick replacement functions, forming a multi-dimensional warning signal of sound, light and smoke in noisy environments or complex scenarios, realizing a full-link safety closed loop from early warning, directional pressure relief to active protection, which greatly improves the controllability of thermal runaway accidents in new energy vehicles and the safety of personnel.
[0073] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.
[0074] Throughout this description, numerous specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of these specific details or by other devices, systems, components, methods, parts, materials, components, etc. In other instances, well-known structures, materials, or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.
[0075] Throughout this specification, references to "an embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention, but not necessarily in all embodiments. Therefore, the various representations of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic of any specific embodiment of the present invention can be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the present invention described and illustrated herein may be based on the teachings herein and will be considered part of the spirit and scope of the present invention.
[0076] It should also be understood that one or more of the elements shown in the figures may be implemented in a more separate or more integrated manner, or may even be removed because they are inoperable in certain circumstances or provided because they may be useful for a particular application.
[0077] Furthermore, unless otherwise expressly stated, any arrows in the accompanying drawings should be considered illustrative only and not limiting. Additionally, unless otherwise stated, the term "or" as used herein is generally intended to mean "and / or". Where a term is anticipated to provide a separation or combination capability that is unclear, a combination of components or steps will also be considered as indicated.
[0078] As used herein and throughout the claims below, unless otherwise specified, “a” and “the” include the plural references. Similarly, as used herein and throughout the claims below, unless otherwise specified, “in” means “in” and “on”.
[0079] The above description of the embodiments shown in this utility model (including the content set forth in the abstract of the specification) is not intended to be an exhaustive enumeration or to limit the utility model to the precise forms disclosed herein. Although specific embodiments and examples of the utility model have been described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the utility model, as will be recognized and understood by those skilled in the art. As indicated, these modifications can be made to the utility model in accordance with the above description of the embodiments described herein, and such modifications will be within the spirit and scope of the utility model.
[0080] This document has generally described the systems and methods in detail to aid in understanding the present invention. Furthermore, various specific details have been set forth to provide a general understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention can be practiced without one or more specific details, or using other devices, systems, accessories, methods, components, materials, parts, etc. In other instances, well-known structures, materials, and / or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.
[0081] Therefore, although the present invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the scope of the above disclosure, and it should be understood that in some cases, certain features of the present invention may be adopted without departing from the scope and spirit of the invention and without corresponding use of other features. Thus, many modifications can be made to adapt a particular environment or material to the essential scope and spirit of the present invention. The present invention is not intended to be limited to the specific terms used in the following claims and / or the specific embodiments disclosed as the best mode of carrying out the present invention, but the present invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of the present invention will be determined only by the appended claims.
Claims
1. A battery pack, characterized in that, include: Box (10); An explosion-proof valve (20) is provided in the housing (10), and the explosion-proof valve (20) includes a pressure relief port (21); A flow guide (30) is connected to the pressure relief port (21), and the flow guide (30) includes an exhaust port (31) facing the outside atmosphere; An alarm unit (40) is disposed within the flow guide (30). The alarm unit (40) includes a turbulence sound-emitting hole (41) and a flow channel (42). The flow channel (42) connects the turbulence sound-emitting hole (41) and the pressure relief port (21).
2. The battery pack according to claim 1, characterized in that, The cross-sectional area of the flow channel (42) gradually decreases from the air inlet end to the air outlet end.
3. The battery pack according to claim 2, characterized in that, The ratio of the cross-sectional area of the inlet end to the cross-sectional area of the outlet end of the flow channel (42) is 2:1 to 100:
1.
4. The battery pack according to claim 1, characterized in that, The explosion-proof valve (20) is disposed on the side wall of the housing (10), and the exhaust port (31) is disposed facing downward.
5. The battery pack according to claim 4, characterized in that, The alarm unit (40) is connected to the guide member (30) via a latching part (44). The latching part (44) is configured such that when a high-temperature airflow passes through the latching part (44), the latching part (44) can disconnect so that the alarm unit (40) can detach from the guide member (30) through the exhaust port (31).
6. The battery pack according to claim 5, characterized in that, The alarm unit (40) is located at the position of minimum cross-sectional area inside the guide member (30).
7. The battery pack according to claim 5, characterized in that, The latching part (44) is made of a first material, which is configured to melt at high temperatures.
8. The battery pack according to claim 7, characterized in that, The rest of the alarm unit (40) is also made of the first material.
9. The battery pack according to claim 8, characterized in that, The alarm unit (40) further includes a second material configured to generate smoke at high temperatures.
10. The battery pack according to claim 1, characterized in that, The alarm unit (40) includes a resonant cavity (43), and the turbulence sound-emitting hole (41) is located between the resonant cavity (43) and the flow channel (42).
11. The battery pack according to claim 1, characterized in that, The turbulence-generating hole (41) is oriented horizontally, and the guide member (30) has a through hole (32) at the position corresponding to the turbulence-generating hole (41).
12. The battery pack according to claim 1, characterized in that, The guide (30) has an open side, which is fitted onto the box (10) to form a chamber. The pressure relief port (21) is located inside the chamber. An exhaust channel (33) communicating with the exhaust port (31) is provided below the chamber. The alarm unit (40) is located inside the exhaust channel (33).
13. The battery pack according to claim 12, characterized in that, The cross-sectional area of the exhaust channel (33) gradually increases from the end away from the exhaust port (31) to the end closer to the exhaust port (31).
14. The battery pack according to claim 13, characterized in that, The ratio of the cross-sectional area of the exhaust port (31) to the cross-sectional area of the end of the exhaust channel (33) away from the exhaust port (31) is 2:1 to 100:
1.
15. The battery pack according to claim 1, characterized in that, The flow guide (30) is a heat-resistant metal part.
16. The battery pack according to claim 1, characterized in that, The alarm unit (40) is integrated with the flow guide (30) or the explosion-proof valve (20).