Battery pack

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery pack. The battery pack comprises a box body, and a battery cell assembly, a liquid leakage detection device and a BMS (Battery Management System) which are arranged in the box body, wherein a liquid cooling channel is arranged in a bottom plate of the box body, a liquid cooling medium is arranged in the liquid cooling channel, and the liquid cooling channel is in heat transfer connection with the battery cell assembly; the liquid leakage detection device is mounted on an inner wall plate of the box body; the BMS is in communication connection with the liquid leakage detection device, and the BMS can receive and process data information detected by the liquid leakage detection device and judge whether to output an alarm signal to the outside or not. Through the arrangement of the battery pack, when a liquid cooling medium leaks from the bottom plate of the box body or water enters the box body, the BMS can immediately output an alarm signal to the outside, so that liquid leakage treatment of the battery pack can be carried out in time. Therefore, the liquid leakage phenomenon in the box body can be found and solved before the battery pack is on fire, so that the battery pack is effectively prevented from being on fire, and the safety of the battery pack is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery pack. Background Art

[0002] With the increasing prevalence of power battery systems, leakage or water ingress from the liquid cooling plate within the battery pack has increased, potentially leading to battery fires in severe cases. To address this issue, existing technologies have disclosed an integrated power lithium battery leakage alarm and fire extinguishing device. This device, through the provision of a detection module and a fire extinguishing module, can online detect the concentration of volatile gases, smoke concentration, and air temperature within the power lithium battery pack. It issues alarms for leakage, smoke, and high temperatures, thus promptly alerting personnel to investigate potential internal hazards within the power lithium battery pack. The fire extinguishing module can also extinguish fires promptly, effectively improving safety.

[0003] However, the above device cannot detect the leakage of the liquid cooling plate or the water intrusion into the battery pack in time, so there is still a certain response delay and the safety factor is still not high. Utility Model Content

[0004] The purpose of the present utility model is to provide a battery pack that can further improve the safety of the battery pack during use.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] The battery pack includes a box, battery cell components, a leakage detection device, and a BMS, including:

[0007] The bottom plate of the box body is provided with a liquid cooling channel inside, the liquid cooling channel is provided with a liquid cooling medium, and the liquid cooling channel is heat-conductingly connected to the battery core assembly;

[0008] The liquid leakage detection device is installed on the inner wall plate of the box;

[0009] The BMS is communicatively connected to the liquid leakage detection device, and the BMS can determine whether to output an alarm signal based on the data information detected by the liquid leakage detection device.

[0010] Preferably, the battery pack further comprises an insulating baffle, and the insulating baffle is laid on at least a position on the bottom plate opposite to the leakage detection device.

[0011] Preferably, the liquid leakage detection device is spaced apart from the bottom plate by a preset distance.

[0012] Preferably, along a preset direction, the battery cell assembly includes a plurality of single battery cells arranged in a regular pattern, and a heat insulating sheet is sandwiched between adjacent single battery cells.

[0013] Preferably, along the preset direction, the thickness of the thermal insulation sheet is greater than or equal to 0.6 mm and less than or equal to 1.2 mm.

[0014] Preferably, the battery cell assembly further includes a CCS assembly, and the CCS assembly includes a CCS bracket and a buffer gasket, wherein:

[0015] The CCS bracket is arranged on a side of the single cell having a top cover plate, and the CCS bracket is provided with a vent hole, which is connected to the pressure relief valve on the top cover plate;

[0016] The buffer gasket is laid on the CCS bracket, and an exhaust port is provided on the buffer gasket. The exhaust port is connected to the air vent, and a covering piece is provided at the exhaust port. The covering piece is configured so that when the actual pressure borne by the covering piece is greater than the preset pressure, the covering piece can open the exhaust port so that the gas discharged from the pressure relief valve can be discharged outward through the exhaust port.

[0017] Preferably, the covering piece includes a fixed portion and a movable portion that are connected to each other, the fixed portion is fixedly connected to the buffer gasket, and the movable portion covers the exhaust port and is movably connected to the buffer gasket. When the actual pressure borne by the movable portion is greater than a preset pressure, the movable portion can open the exhaust port so that the gas discharged from the pressure relief valve can be discharged outward through the exhaust port.

[0018] Preferably, the CCS assembly further comprises a support gasket, which is clamped and fixed between the single cell and the CCS bracket, and a via is provided on the support gasket, which is connected to the pressure relief valve and the air vent.

[0019] Preferably, the CCS assembly further includes a bus and a temperature acquisition probe. The bus is arranged on the CCS bracket and is arranged in contact with the single battery cell. The bus can electrically connect multiple single batteries. The temperature acquisition probe is connected to the BMS and the bus.

[0020] Preferably, the busbar includes a connecting aluminum bar and two output-level aluminum bars, the connecting aluminum bar and the output-level aluminum bar are both fixedly connected to the CCS bracket, the connecting aluminum bar is used to connect the multiple single cells in series, along the preset direction, the two output-level aluminum bars are provided at both ends of the CCS assembly and connected to the connecting aluminum bar, the output-level aluminum bar is used to connect the single cells to external electrical equipment;

[0021] The output-stage aluminum bar and the connecting aluminum bar are both fixedly provided with the temperature acquisition probe.

[0022] Preferably, the battery pack also includes a fire detection device, which includes a shell, a temperature probe and a gas probe. The shell is fixed in the box, and the temperature probe and the gas probe are fixed in the shell and are both communicatively connected to the BMS. The temperature probe can detect the air temperature in the box, and the gas probe can detect the gas concentration in the box. The BMS can determine whether to output an alarm signal based on the air temperature detected by the temperature probe and the gas concentration detected by the gas probe.

[0023] Preferably, the battery pack further includes a fire extinguishing device, which is fixed inside the box.

[0024] The beneficial effects of the present invention are as follows: The present invention provides a battery pack that can detect whether there is leakage in the battery pack through a leakage detection device. When the bottom plate of the battery pack leaks liquid cooling medium or water enters the battery pack, the BMS can receive the leakage information sent by the liquid detection device and output an alarm signal to the outside, so that the leakage can be handled in time. By setting up the leakage detection device, leakage in the battery pack can be discovered and resolved before the battery pack catches fire, thereby effectively preventing the battery pack from catching fire and further improving the safety of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a battery pack provided by an embodiment of the present utility model;

[0026] Figure 2 This is a three-dimensional diagram of the internal structure of the battery pack provided by an embodiment of the present invention from a first viewing angle;

[0027] Figure 3 is a perspective view of the internal structure of the battery pack provided by an embodiment of the present utility model from a second viewing angle;

[0028] Figure 4 This is a top view of the internal structure of the battery pack provided by an embodiment of the present utility model;

[0029] Figure 5 This is a partial structural exploded view of the battery cell assembly provided by an embodiment of the present utility model;

[0030] Figure 6 It is an exploded view of the CCS assembly provided by an embodiment of the present utility model;

[0031] Figure 7 is a top view of a CCS assembly provided by an embodiment of the present utility model;

[0032] Figure 8 It is a partial structural diagram of the buffer gasket provided by an embodiment of the utility model.

[0033] In the picture:

[0034] 1. Box body; 11. Bottom plate; 12. Box cover; 13. External plug; 14. Bracket; 15. Insulation baffle;

[0035] 2. Cell assembly; 21. Single cell; 22. Thermal insulation sheet; 23. CCS assembly; 231. CCS bracket; 2311. Ventilation hole; 232. Buffer gasket; 2321. Exhaust port; 2322. Covering sheet; 23221. Fixed part; 23222. Movable part; 233. Support gasket; 2331. Via hole; 234. Busbar; 2341. Connecting aluminum busbar; 2342. Output stage aluminum busbar; 235. Temperature acquisition probe; 236. Voltage acquisition probe; 237. Collection wiring harness;

[0036] 3. Liquid leakage detection device;

[0037] 4. BMS;

[0038] 5. Fire detection device;

[0039] 6. Fire extinguishing equipment. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0041] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0042] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0043] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0044] The technical solution provided by the present utility model is described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] Combine Figures 1 to 8 As shown, this embodiment provides a battery pack, including a box body 1, and a battery cell assembly 2, a leakage detection device 3 and a BMS 4 installed in the box body 1.

[0046] The box body 1 includes a base plate 11 and a cover 12. In this embodiment, the base plate 11 has a liquid cooling channel inside, in which a liquid cooling medium flows. The liquid cooling channel is heat-transferably connected to the battery cell assembly 2, thereby integrating the base plate 11 with the liquid cooling plate in a conventional battery pack. This saves space for an additional liquid cooling plate and makes the battery pack provided by this embodiment more compact. The cover 12 has a square shell structure and has a storage space for the battery cell assembly 2. After the battery cell assembly 2, leakage detection device 3, alarm, and BMS 4 are installed on the base plate 11, the cover 12 is installed to seal and protect the internal structure of the battery pack 2.

[0047] Optionally, in this embodiment, the battery pack includes two sets of battery cell assemblies 2 connected in series to meet actual energy density requirements. Of course, in other embodiments, based on factors such as the battery pack storage space and actual operating conditions, one or more battery cell assemblies 2 can be provided in the battery pack. Therefore, the present invention does not limit the number of battery cell assemblies 2 provided.

[0048] In this embodiment, the two battery cell assemblies 2 have the same structure, so the battery cell assemblies 2 will be described below by taking one of the battery cell assemblies 2 as an example, and the structure of the other battery cell assembly 2 will not be described in detail.

[0049] Specifically, along the preset direction (i.e., along Figure 5 The battery cell assembly 2 includes a plurality of regularly arranged single cells 21, with a thermal insulation sheet 22, such as an aerogel layer, interposed between adjacent single cells 21. The aerogel layer provides thermal insulation and flame retardancy, effectively preventing heat generated by a thermally runaway single cell 21 from spreading to adjacent single cells 21. Furthermore, the aerogel layer is lightweight, having a minimal impact on the weight of the battery cell assembly 2. It also absorbs the expansion force of the single cells 21, effectively reducing the impact of extrusion deformation on adjacent single cells 21.

[0050] Furthermore, along the X-axis, the thickness of the thermal insulation sheet 22 is greater than or equal to 0.6 mm and less than or equal to 1.2 mm. For example, the thickness of the thermal insulation sheet 22 may be 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, or 1.2 mm. Preferably, in this embodiment, the thermal insulation sheet 22 has a thickness of 0.7 mm and a cross-sectional size that is the same as the cross-sectional size of the main heat dissipation surface of the single battery cell 21, thereby meeting the requirement of preventing heat transfer to adjacent single battery cells 21 under specific operating conditions.

[0051] Specifically, refer to Figure 5 、 Figure 6 and Figure 8 As shown, the battery cell assembly 2 provided in this embodiment also includes a CCS assembly 23, and the CCS assembly 23 includes a CCS bracket 231 and a buffer gasket 232. Among them, the CCS bracket 231 is arranged on the side of the single battery cell 21 with a top cover plate, and a vent 2311 is opened through the CCS bracket 231. The vent 2311 is arranged opposite to and connected to the pressure relief valve on the top cover plate. The buffer gasket 232 is laid on the CCS bracket 231, and an exhaust port 2321 connected to the vent 2311 is opened on the buffer gasket 232, and a cover sheet 2322 is provided at the exhaust port 2321. During use, when the actual pressure borne by the cover sheet 2322 is greater than the preset pressure, the cover sheet 2322 can open the closed exhaust port 2321 so that the gas discharged from the pressure relief valve can be discharged outward through the exhaust port 2321.

[0052] One implementation method of this embodiment is to refer to Figure 8As shown, the cover sheet 2322 specifically includes a fixed portion 23221 and a movable portion 23222 that are connected to each other, wherein the fixed portion 23221 is fixedly connected to the buffer sheet 232, and the movable portion 23222 is covered on the exhaust port 2321 and is movably connected to the buffer gasket 232. Through the above-mentioned arrangement, when the actual pressure borne by the movable portion 23222 is greater than the preset pressure, the movable portion 23222 can be folded upward to open the exhaust port 2321, so that the exhaust port 2321 is open, thereby allowing the gas discharged from the pressure relief valve to be discharged outward, thereby reducing the internal pressure of the single battery cell 21 and avoiding the explosion of the single battery cell 21. Moreover, by providing the above-mentioned cover sheet 2322, it is also possible to effectively prevent high-temperature electrolyte from being sprayed onto the adjacent single battery cell 21, resulting in the risk of damage to the adjacent normal single battery cell 21.

[0053] Optionally, in this embodiment, the buffer pad 232 is foam, the CCS bracket 231 is made of a PC (polycarbonate) board, and the foam is bonded to the PC board using adhesive.

[0054] Furthermore, in this embodiment, the cross-sectional shapes of the movable portion 23222, the exhaust port 2321 and the air vent 2311 are all the same as the cross-sectional shapes of the pressure relief valve, that is, the cross-sectional shapes of the movable portion 23222, the exhaust port 2321 and the air vent 2311 are all arc-shaped, so as to adapt to the outer shape of the pressure relief valve, thereby being more conducive to exhaust.

[0055] Specifically, refer to Figure 5 As shown, the CCS assembly 23 provided in this embodiment also includes a support gasket 233, which is sandwiched and fixed between the single cell 21 and the CCS bracket 231, so that the CCS bracket 231 and the single cell 21 are fixedly connected through the support gasket 233. On the one hand, it can meet the spatial arrangement requirements of the CCS bracket 231, and on the other hand, it can make the CCS bracket 231 avoid the pole assembly protruding from the single cell 21, thereby ensuring that the CCS bracket 231 can be set flat on the single cell 21 and avoiding deformation of the CCS bracket 231. Furthermore, the support gasket 233 is also made of foam material. Since the foam material also has good shock absorption and vibration reduction effects, it can reduce the possibility of hard contact between the CCS bracket 231 and the single cell 21.

[0056] In this embodiment, a through hole 2331 is provided on the support gasket 233 , and the through hole 2331 is connected to the pressure relief valve and the air vent 2311 to facilitate the discharge of gas.

[0057] More specifically, the CCS assembly 23 provided in this embodiment further includes a busbar 234 and a temperature acquisition probe 235. The busbar 234 is disposed on the CCS bracket 231 and can be in contact with the single cell 21 through a through-hole on the CCS bracket 231. The busbar 234 can electrically connect multiple single cells 21. The temperature acquisition probe 235 is connected to the BMS 4 and the busbar 234. The temperature acquisition probe 235 is connected to the BMS 4 via the temperature acquisition probe 235, allowing the BMS 4 to monitor the temperature status of the cell assembly 2 in real time. If an abnormality (such as overheating) is detected, protective measures can be taken to prevent safety accidents and ensure the safe use of the battery pack.

[0058] Among them, reference Figure 7 As shown, the busbar 234 includes a connecting aluminum bar 2341 and two output-level aluminum bars 2342. The connecting aluminum bar 2341 and the output-level aluminum bar 2342 are both fixedly connected to the CCS bracket 231. There are multiple connecting aluminum bars 2341, and adjacent single battery cells 21 are connected in series through the connecting aluminum bars 2341; along the X-axis direction, the two output-level aluminum bars 2342 are arranged at both ends of the CCS assembly 23, one of the output-level aluminum bars 2342 is used to be electrically connected to one pole of the external electrical equipment, such as the positive pole, and the other output-level aluminum bar 2342 is used to be electrically connected to the other pole of the external electrical equipment (the other pole is the negative pole in this case), so that the battery cell assembly 2 can supply power to the external electrical equipment.

[0059] It should be noted that since this embodiment is provided with two battery cell assemblies 2, it is necessary to electrically connect one of the output-stage aluminum bars 2342 in one of the battery cell assemblies 2 to one of the poles of the external electrical device, connect the other output-stage aluminum bar 2342 in one of the battery cell assemblies 2 to one of the output-stage aluminum bars 2342 in the other battery cell assemblies 2, and then electrically connect the other output-stage aluminum bar 2342 in the other battery cell assembly 2 to the other pole of the external electrical device, so that the two battery cell assemblies 2 can serve as positive and negative output modules to supply power to the external electrical device. Of course, it is understandable that in other embodiments, more battery cell assemblies 2 can be connected in series in the above manner in the box 1 to obtain a battery pack with greater energy density and energy storage capacity, and the present invention is not limited to this.

[0060] In actual situations, the output-stage aluminum bar 2342 carries the input / output current of the battery cell assembly 2. Therefore, when the battery cell assembly 2 is charging or discharging, the current passing through the output-stage aluminum bar 2342 is relatively large, causing the temperature of the output-stage aluminum bar 2342 to be relatively high. In addition, due to its positional arrangement, the heat dissipation capacity of the single battery cell 21 located in the middle of the battery cell assembly 2 is insufficient compared to the heat dissipation capacity of the single battery cells 21 located in other positions. Therefore, in this embodiment, the above-mentioned temperature acquisition probes 235 are provided on both output-stage aluminum bars 2342 and the two connecting aluminum bars 2341 located in the middle of the CCS assembly 23 to detect the actual temperatures of the four higher temperature locations on a battery cell assembly 2. By detecting the actual temperatures at these four points, not only can the safety of the battery cell assembly 2 be accurately determined, but the number of temperature acquisition probes 235 used can also be effectively controlled, thereby saving costs.

[0061] Of course, in other embodiments, the aforementioned temperature acquisition probe 235 may be provided on each connecting aluminum bar 2341 to detect the actual temperature of each single battery cell 21, thereby enabling comprehensive and specific monitoring and control of the operating status of the battery cell assembly 2. It should be noted that the number of temperature acquisition probes 235 provided is affected by factors such as the type of panel and the size of the box 1. Therefore, those skilled in the art may select the number of temperature acquisition probes 235 based on actual conditions.

[0062] Alternatively, as Figure 1 As shown, the box 1 is located Figure 2 Two external plugs 13 are installed on the center-left sidewall. One of the output-stage aluminum bars 2342 in the upper battery assembly 2 is connected to one external plug 13, while the other output-stage aluminum bar 2342 in the lower battery assembly 2 is connected to the other external plug 13. This allows external electrical equipment to be electrically connected to both battery assemblies 2 via the two external plugs 13. Furthermore, the external plug 13 can rotate 360° around its center, extending its applicability and allowing the power harness to be installed at any 360° angle. This provides greater flexibility, facilitating wiring and routing, and reducing assembly time.

[0063] refer to Figure 7 As shown, the output-stage aluminum bar 2342 and the connecting aluminum bar 2341 are also provided with a voltage acquisition probe 236. The temperature acquisition probe 235 and the voltage acquisition probe 236 are both connected to the BMS4 through the acquisition harness 237. The BMS4 monitors the operating voltage, temperature, current and other parameters of the single battery cell 21 in real time to detect the health status of the single battery cell 21. The BMS4 can also control the working status of the single battery cell 21 in real time to protect the battery. Figure 3As shown, a bracket 14 is fixedly provided on the box body 1, and the BMS 4 is mounted on the bracket 14. In this embodiment, the temperature acquisition probe 235 and the voltage acquisition probe 236 are both fixed by glue, which can achieve multi-point measurement with high measurement accuracy.

[0064] Specifically, refer to Figure 2 As shown, the leakage detection device 3 has a liquid detection probe, which is installed on the inner wall of the box 1. Since the battery pack may leak in the liquid cooling channel or water may enter the box 1 during use, this embodiment can detect whether there is leakage in the box 1 through the liquid detection probe. The BMS 4 receives and processes the data information detected by the liquid detection probe and determines whether to output an alarm signal to the outside, so that the staff can receive the leakage information in time and process it, thereby avoiding safety risks such as short circuit and fire in the battery pack due to leakage. Through the above-mentioned settings, the battery pack can detect and solve the leakage phenomenon in the box 1 before the fire occurs, thereby greatly improving the safety of the battery pack.

[0065] In one embodiment of the present invention, an alarm device (not shown) is further provided in the box 1 and is in communication with the BMS 4, so that when the BMS 4 detects a liquid leak in the box 1, it can immediately control the alarm device to be turned on and send an alarm signal to the outside world in the form of sound, light, or a combination of sound and light. Of course, in other embodiments, the BMS 4 can also transmit the liquid leakage alarm information to the staff through outputting warnings such as text messages or emails, and the present invention is not limited to this.

[0066] Optionally, the liquid detection probe is made of metal. When there is a leak in the box 1, once the leaked liquid comes into contact with the probe, the liquid detection probe will respond quickly, and its conductivity, resistance, voltage or current value will change significantly. The detection circuit will then immediately send this change value to the BMS 4 for processing. This can effectively improve the response speed of the liquid leakage detection device 3 and remind the staff to promptly remove the leaked liquid in the battery pack to ensure the safety of the battery pack.

[0067] Optionally, the leakage detection device 3 can be fixed to the bottom plate 11 by fixing parts such as threaded connectors. Compared with fixing it to the peripheral side wall of the box cover 12, the operation of fixing the leakage detection device 3 to the box cover 12 using a fixing bracket can be omitted, the installation method is simpler, and costs are saved. In addition, the liquid detection probe is separated from the bottom plate 11 by a preset distance, so that when leakage actually occurs in the battery pack and the leakage volume forms a certain height in the box body 1, the liquid detection probe can touch the leakage and send leakage information to the BMS 4, thereby avoiding the possibility of false alarms. For example, in this embodiment, the preset distance between the liquid detection probe and the bottom plate 11 is 1 mm.

[0068] In this embodiment, the base plate 11 is made of metal. In order to reduce the interference of the base plate 11 on the liquid detection probe which is also made of metal, in this embodiment, an insulating baffle 15 is laid on the base plate 11 at a position opposite to the liquid detection probe. The insulating baffle 15 is arranged at intervals between the base plate 11 and the liquid detection probe to reduce the electrostatic interference of the base plate 11 on the liquid detection probe, thereby improving the response accuracy of the liquid detection probe.

[0069] It should be noted that the insulating baffle 15 is made of PC material, and the insulating baffle 15 and the base insulating film are made of the same material, so as to effectively control the production cost of the battery pack, simplify the production process and improve production efficiency.

[0070] Optionally, the battery pack provided in this embodiment also includes a fire detection device 5 arranged in the box body 1. The fire detection device 5 includes a shell, a temperature probe and a gas probe. The shell meets the UL94-V0 flame retardant standard. For example, copper-zinc alloy, aluminum-silicon alloy and other materials can be used. Flame retardant materials can also be added to the surface of the shell. The present invention is not limited to this; the temperature probe and the gas probe are both fixedly arranged in the shell, and are both connected to the BMS4 through an adapter harness, and can realize CAN communication connection with the BMS4. The temperature probe can detect the air temperature in the box body 1, and the gas probe can detect the gas concentration in the box body 1. The BMS4 can determine whether to turn on the alarm through the air temperature detected by the temperature probe and the gas concentration detected by the gas probe.

[0071] Optionally, in this embodiment, the housing of the fire detection device 5 is fixed to the bracket 14. By placing the fire detection device 5 on the bracket 14, on the one hand, the compactness of the installation of the fire detection device 5 and components such as the BMS 4 is improved, and on the other hand, the connection distance between the temperature sensor and gas sensor in the fire detection device 5 and the BMS 4 can be shortened, thereby facilitating the arrangement of the adapter harness.

[0072] During actual use, the single cell 21 may produce some gas, such as carbon monoxide gas, during the activation process of charging, which causes the internal pressure of the single cell 21 to increase. When the pressure reaches a certain level, the outer shell will rupture, causing the electrolyte to leak. Since the electrolyte of the single cell 21 is highly volatile and flammable, it will react with water to generate heat, which makes the single cell 21 prone to fire when charging. Based on the above situation, for example, when the air temperature in the box 1 is detected to be 70°C by the above-mentioned temperature sensor, and the carbon monoxide concentration is detected to reach 190ppm by the gas sensor, the temperature sensor and the gas sensor can immediately send a warning signal to the BMS4, so that the BMS4 can immediately control the alarm to issue an alarm message, reminding the staff to make emergency treatment in time.

[0073] It should be noted that the alarm levels are different at different temperatures and can be divided into level two, level three and level four, and the temperatures corresponding to different alarm levels can be adjusted according to actual conditions. The alarm information may include sound or light. For example, when sound is used as the alarm information medium, it should be greater than 90DB.

[0074] Optionally, the battery pack provided in this embodiment further includes a fire extinguishing device 6. In one implementation of this embodiment, the fire extinguishing device 6 utilizes an aerosol. Aerosols are non-toxic, non-corrosive, can be stored at room temperature, are compact, and are easy to install. In this embodiment, the fire extinguishing device 6 is integrated with the housing of the fire detection device 5. The aerosol contains a fire extinguishing medium. Once a fire occurs somewhere on the battery cell assembly 2, the aerosol melts due to heat and releases the internal fire extinguishing medium to extinguish the fire. This allows for rapid fire extinguishing at the initial stage, reducing the likelihood of fire development.

[0075] Specifically, the fire extinguishing medium includes an aerosol generator and a chemical coolant. The aerosol generator can quickly extinguish the flame, while the chemical coolant can further reduce the temperature and prevent re-ignition, thereby improving the fire extinguishing efficiency and reliability.

[0076] It should be noted that in this embodiment, when a fire occurs on the battery cell assembly 2, the BMS4 can also simultaneously receive the air temperature detected by the temperature sensor and the gas concentration detected by the gas sensor, so that while the fire extinguishing device 6 extinguishes the fire in the box 1, the BMS4 can also control the alarm to issue an alarm message, thereby achieving dual protection of the alarm and fire extinguishing functions. By simultaneously arranging the fire detection device 5, the fire extinguishing device 6 and the leakage detection device 3 in the box 1, the battery pack can not only detect the temperature and gas concentration when the electrolyte leaks, and the fire extinguishing device 6 can participate in the fire extinguishing while sending a warning signal to the staff, but also can detect in real time whether there is leakage from the bottom plate 11 in the battery pack or water ingress into the box 1, thereby protecting the safety of the battery cell assembly 2 in many aspects, greatly improving the safety and reliability of the battery pack during use.

[0077] Throughout this specification, references to terms such as "some embodiments" and "other embodiments" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0078] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A battery pack, characterized in that: The invention comprises a box (1), a battery cell assembly (2), a leakage detection device (3) and a BMS (4), wherein: The bottom plate (11) of the box (1) has a liquid cooling channel inside, a liquid cooling medium is provided in the liquid cooling channel, and the liquid cooling channel is connected to the battery core assembly (2) in a heat transfer manner; The liquid leakage detection device (3) is installed on the inner wall plate of the box body (1); The BMS (4) is communicatively connected to the liquid leakage detection device (3), and the BMS (4) can determine whether to output an alarm signal based on the data information detected by the liquid leakage detection device (3).

2. The battery pack according to claim 1, wherein: The battery pack further comprises an insulating baffle (15), and the insulating baffle (15) is laid on the bottom plate (11) at least at a position opposite to the liquid leakage detection device (3).

3. The battery pack according to claim 1, wherein: The liquid leakage detection device (3) is spaced apart from the bottom plate (11) by a preset distance.

4. The battery pack according to claim 1, wherein: Along a preset direction, the battery cell assembly (2) comprises a plurality of single battery cells (21) arranged in a regular arrangement, and a heat insulating sheet (22) is sandwiched between adjacent single battery cells (21).

5. The battery pack according to claim 4, characterized in that: Along the preset direction, the thickness of the heat insulation sheet (22) is greater than or equal to 0.6 mm and less than or equal to 1.2 mm.

6. The battery pack according to claim 4, characterized in that: The battery cell assembly (2) further includes a CCS assembly (23), wherein the CCS assembly (23) includes a CCS bracket (231) and a buffer gasket (232), wherein: The CCS bracket (231) is provided on a side of the single cell (21) having a top cover plate, and a vent hole (2311) is provided on the CCS bracket (231), and the vent hole (2311) is connected to a pressure relief valve on the top cover plate; The buffer gasket (232) is laid on the CCS bracket (231), and an exhaust port (2321) is provided on the buffer gasket (232), and the exhaust port (2321) is connected to the air vent (2311). A cover sheet (2322) is provided at the exhaust port (2321), and the cover sheet (2322) is configured so that when the actual pressure borne by the cover sheet (2322) is greater than a preset pressure, the cover sheet (2322) can open the exhaust port (2321) so that the gas discharged from the pressure relief valve can be discharged outward through the exhaust port (2321).

7. The battery pack according to claim 6, characterized in that: The cover sheet (2322) comprises a fixed portion (23221) and a movable portion (23222) connected to each other, wherein the fixed portion (23221) is fixedly connected to the buffer gasket (232), and the movable portion (23222) covers the exhaust port (2321) and is movably connected to the buffer gasket (232). When the actual pressure borne by the movable portion (23222) is greater than a preset pressure, the movable portion (23222) can open the exhaust port (2321) so that the gas discharged from the pressure relief valve can be discharged outward through the exhaust port (2321).

8. The battery pack according to claim 6, wherein: The CCS assembly (23) further comprises a support gasket (233), the support gasket (233) being sandwiched and fixed between the single battery cell (21) and the CCS bracket (231), the support gasket (233) being provided with a through hole (2331), the through hole (2331) being connected to the pressure relief valve and the vent hole (2311).

9. The battery pack according to claim 6, wherein: The CCS assembly (23) further includes a busbar (234) and a temperature acquisition probe (235); the busbar (234) is arranged on the CCS bracket (231) and is arranged in contact with the single battery cell (21); the busbar (234) can electrically connect a plurality of the single battery cells (21); and the temperature acquisition probe (235) is connected to the BMS (4) and the busbar (234).

10. The battery pack according to claim 9, characterized in that: The busbar (234) comprises a connecting aluminum bar (2341) and two output-level aluminum bars (2342); the connecting aluminum bar (2341) and the output-level aluminum bar (2342) are both fixedly connected to the CCS bracket (231); the connecting aluminum bar (2341) is used to connect a plurality of the single cells (21) in series; along the preset direction, the two output-level aluminum bars (2342) are provided at both ends of the CCS assembly (23) and are connected to the connecting aluminum bar (2341); the output-level aluminum bar (2342) is used to connect the single cells (21) to external electrical equipment; The output-stage aluminum bar (2342) and the connecting aluminum bar (2341) are both fixedly provided with the temperature acquisition probe (235).

11. The battery pack according to any one of claims 1 to 10, characterized in that: The battery pack further comprises a fire detection device (5), the fire detection device (5) comprising a shell, a temperature probe and a gas probe, the shell being fixedly mounted in the box (1), the temperature probe and the gas probe being fixedly mounted in the shell and both being communicatively connected to the BMS (4), the temperature probe being capable of detecting the air temperature in the box (1), the gas probe being capable of detecting the gas concentration in the box (1), and the BMS (4) being capable of determining whether to output an alarm signal based on the air temperature detected by the temperature probe and the gas concentration detected by the gas probe.

12. The battery pack according to claim 11, wherein: The battery pack further comprises a fire extinguishing device (6), and the fire extinguishing device (6) is fixedly arranged in the box (1).

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