Battery pack and powered device

Abstract

The battery pack provided by the present disclosure can improve the structural strength of the battery pack, improve the impact resistance of the battery pack, reduce the expansion degree of the battery monomer, reduce the capacity attenuation of the battery monomer, improve the performance of the battery monomer, and help improve the overall reliability and safety of the battery pack.

Description

Technical Field

[0001] This disclosure relates to the field of battery pack technology, and more specifically, to a battery pack and an electrical device. Background Technology

[0002] In related technologies, existing battery packs have problems with low structural strength and poor impact resistance during bottom ball impact tests. Summary of the Invention

[0003] The purpose of this disclosure is to provide a battery pack and electrical device that can improve the structural strength of the battery pack while also enhancing its impact resistance, thereby helping to improve the overall reliability and safety of the battery pack.

[0004] To achieve the above objectives, a first aspect of this disclosure provides a battery pack comprising: a plurality of battery cells; and a housing, wherein the plurality of battery cells are disposed within the housing, and the housing has a cavity in its wall, the cavity being filled with a fluid medium.

[0005] Optionally, the fluid medium is a liquid; the liquid is a cooling liquid.

[0006] Optionally, the cooling liquid is a mixture of ethylene glycol and water; in the cooling liquid composed of the mixture of ethylene glycol and water, the percentage of ethylene glycol is 50%-70%.

[0007] Optionally, the fluid medium is a compressed gas.

[0008] Optionally, the compressed gas is an inert gas.

[0009] Optionally, the inert gas includes at least one of argon, xenon, and sulfur hexafluoride.

[0010] Optionally, the compressed gas includes carbon dioxide.

[0011] Optionally, the fluid medium is configured such that the pressure inside the cavity is 1 kPa-3 kPa.

[0012] Optionally, the airtightness of the cavity is not less than 5 kPa.

[0013] Optionally, the cavity includes a pressure relief channel, and the wall of the housing is provided with a first pressure relief component that connects the battery cell and the pressure relief channel.

[0014] Optionally, the pressure relief channel has a pressure relief port, and a pressure relief switch is provided at the pressure relief port to block the pressure relief port. The pressure relief switch is configured to open the pressure relief port when the battery cell experiences thermal runaway.

[0015] Optionally, the number of pressure relief ports is multiple and they are arranged at intervals.

[0016] Optionally, the pressure relief switch includes a reinforcing plate, which is detachably connected to the outer wall of the housing and blocks the pressure relief port.

[0017] Optionally, the reinforcing plate is bonded to the housing.

[0018] Optionally, the connection strength between the reinforcing plate and the shell is not less than 5 kPa.

[0019] Optionally, the opening pressure of the pressure relief switch is not less than the sum of the preset pressure and the pressure inside the cavity.

[0020] Optionally, the housing includes a base plate, and the pressure relief channel is disposed within the base plate.

[0021] Optionally, the base plate is further provided with an injection port communicating with the pressure relief channel, for filling the pressure relief channel with the fluid medium through the injection port.

[0022] Optionally, a plurality of the battery cells are bonded to the top wall of the base plate by adhesive. An adhesive-blocking structure is provided between the top wall and the battery cells. The adhesive-blocking structure forms a receiving channel for accommodating the first pressure relief component and communicating with the communication port. The adhesive-blocking structure is used to block the first pressure relief component and the adhesive.

[0023] Optionally, each of the receiving channels contains at least one of the first pressure relief components.

[0024] Optionally, the base plate includes a first plate and a second plate arranged opposite to each other along a first direction, with the pressure relief channel formed between the first plate and the second plate. The first plate is provided with the communication port, and the second plate is provided with the pressure relief port.

[0025] Optionally, the first plate includes a support plate structure with the communication port provided on the support plate structure, and the support plate structure is used to support the battery cell; or the first plate includes a liquid cooling plate structure with the communication port provided on the liquid cooling plate structure, and the liquid cooling plate structure is used to cool the battery cell.

[0026] Optionally, a temperature sensing element is provided in the pressure relief channel for monitoring the temperature of the fluid medium; and / or a driving structure is provided in the pressure relief channel for driving the fluid medium to flow in the pressure relief channel.

[0027] Optionally, the housing has a receiving groove for accommodating the plurality of battery cells, and the battery pack further includes a cover that covers the housing and closes the receiving groove, the cover being connected to the housing by a potting compound structure formed by potting compound filled into the receiving groove.

[0028] Optionally, the potting compound structure includes a first potting compound structure and a second potting compound structure connected together. The first potting compound structure is arranged adjacent to the bottom plate of the housing, and the second potting compound structure is arranged adjacent to the cover. The first potting compound structure is formed of non-foaming adhesive, and the second potting compound structure is formed of foaming adhesive.

[0029] A second aspect of this disclosure provides an electrical device including the battery pack provided in the first aspect.

[0030] Through the above-described technical solution, namely the battery pack provided in this disclosure, the battery pack can improve the structural strength of the casing by filling the cavity within the casing wall with a fluid medium. This helps to reduce the risk of casing deformation caused by factors such as mechanical impacts or bottom ball impact tests. The battery pack has higher structural strength and stronger impact resistance. Furthermore, the higher structural strength of the casing can better constrain the individual battery cells inside the casing, reducing the expansion of the individual battery cells and thus reducing the capacity decay of the individual battery cells. This improves the performance of the individual battery cells and helps to ensure that the entire battery pack has high reliability and safety.

[0031] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0032] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of the battery pack provided in an exemplary embodiment of this disclosure; Figure 2 This is an exploded schematic diagram of a battery pack provided in an exemplary embodiment of this disclosure; Figure 3 This is a cross-sectional view of the battery pack provided in an exemplary embodiment of this disclosure; Figure 4 yes Figure 3 A magnified view of a portion of location A in the diagram; Figure 5 This is a schematic diagram of the structure of the battery pack housing provided in an exemplary embodiment of this disclosure; Figure 6 This is a schematic diagram of the structure of the base plate of the battery pack provided in an exemplary embodiment of this disclosure; Figure 7 This is a schematic diagram of the structure of the second plate of the battery pack provided in an exemplary embodiment of this disclosure; Figure 8 yes Figure 7 Cross-sectional view at position BB in the middle; Figure 9 yes Figure 8 A magnified view of a portion of the area at position C; Figure 10 This is a bottom view of the first plate of the battery pack provided in an exemplary embodiment of this disclosure.

[0033] Explanation of reference numerals in the attached figures 1-Battery cell; 110-First pressure relief component; 2-Housing shell; 210-Receiving groove; 220-Cavity; 221-Pressure relief channel; 230-Connecting port; 240-Pressure relief port; 250-Pressure relief switch; 251-Reinforcing plate; 260-Base plate; 261-First plate; 262-Second plate; 263-Injection port; 270-Frame; 3-Adhesive; 4-Glue-blocking structure; 410-Receiving channel; 5-Temperature sensing element; 6-Drive structure; 7-Cover; 8-Potting compound structure; 810-First potting compound structure; 820-Second potting compound structure; 9-Fluid medium; 10-Sealant. Detailed Implementation

[0034] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0035] It should be noted that all actions involving the acquisition of signals, information, or data in this disclosure are carried out in compliance with the relevant data protection laws and policies of the country where the location is situated, and with authorization from the owner of the relevant device.

[0036] In this disclosure, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower dimensions within the space of the battery pack when it is in use. "Inner" and "outer" refer to the inner and outer dimensions relative to the outline of the component or structure itself. Furthermore, it should be noted that terms such as "first" and "second" are used to distinguish one element from another and do not indicate sequence or importance. Additionally, in the description with reference to the accompanying drawings, the same reference numerals in different drawings denote the same elements.

[0037] According to a first aspect of this disclosure, a battery pack is provided, with reference to... Figures 1 to 10 As shown, the battery pack includes multiple battery cells 1 and a housing 2. The multiple battery cells 1 are disposed inside the housing 2. The housing 2 has a cavity 220 in its wall, and the cavity 220 is filled with a fluid medium 9.

[0038] Through the above-described technical solution, namely the battery pack provided in this disclosure, the battery pack can improve the structural strength of the housing 2 by filling the cavity 220 inside the wall of the housing 2 with a fluid medium 9. This helps to reduce the risk of deformation of the housing 2 caused by mechanical impact or bottom ball impact test of the battery pack. The structure has high strength and stronger impact resistance. Furthermore, the high structural strength of the housing 2 can better constrain the battery cells 1 inside the housing 2, reduce the expansion of the battery cells 1, thereby reducing the capacity decay of the battery cells 1, improving the performance of the battery cells 1, and helping to ensure that the entire battery pack has high reliability and safety.

[0039] In some implementations, reference Figures 1 to 10 As shown, the cavity 220 may include a pressure relief channel 221. The wall of the housing 2 is provided with a first pressure relief component 110 connecting the battery cell 1 and the pressure relief channel 221. Thus, by filling the pressure relief channel 221 with a fluid medium 9, the cavity 220 (pressure relief channel 221) has a certain pressure. For example, the fluid medium 9 is configured to make the pressure in the cavity 220 (pressure relief channel 221) 1Kpa-3Kpa. Thus, compared with the related technology, such as the method where the pressure relief channel is a cavity structure, it is obvious that by filling the pressure relief channel 221 with a fluid medium 9, the pressure relief channel 221 has a certain pressure, thereby improving the structural strength of the housing 2 and the impact resistance of the housing 2, which helps to ensure that the entire battery pack has high reliability and safety.

[0040] Of course, those skilled in the art can also fill any cavity 220 inside the housing 2 with fluid medium 9 as needed. That is, it is understood that it is not limited to the pressure relief channel 221. The purpose is to improve the structural strength of the housing 2 and the impact resistance of the housing 2 by filling the cavity 220 of the housing 2 with fluid medium 9.

[0041] In addition, it should be noted that the specific embodiment in which the pressure in the pressure relief channel 221 is 1Kpa-3Kpa is exemplary, and this disclosure is not limited thereto. Those skilled in the art can adaptively adjust the pressure in the pressure relief channel 221 according to actual application needs. The purpose is to improve the structural strength of the shell 2 and the impact resistance of the shell 2 after the fluid medium 9 is filled into the pressure relief channel 221.

[0042] The fluid medium 9 can be, for example, a liquid. By filling the pressure relief channel 221 with liquid, the hydraulic pressure within the channel can be increased to, for example, 1 kPa-3 kPa, thereby improving the structural strength and impact resistance of the casing 2. Furthermore, filling with liquid allows for heat absorption and vaporization during, for example, battery pack thermal runaway. This not only absorbs heat as the liquid transforms into gas, but the vaporized gas also increases the pressure within the pressure relief channel 221. Thus, when the pressure within the channel 221 exceeds a preset safety pressure, pressure relief can be initiated earlier, contributing to improved overall battery pack safety.

[0043] Alternatively, the fluid medium 9 can also be, for example, compressed gas. In this way, by filling the pressure relief channel 221 with compressed gas at a certain pressure, the gas pressure in the pressure relief channel 221 can be, for example, 1 kPa-3 kPa, thereby improving the structural strength of the shell 2 and its impact resistance. Alternatively, the fluid medium 9 can also be, for example, emulsion liquid. This disclosure does not specifically limit such variations, and those skilled in the art can design them adaptively according to actual application requirements.

[0044] Taking the fluid medium 9 as a liquid as an example, the liquid can be, for example, a cooling liquid. This can improve the structural strength and impact resistance of the casing 2, while also directly or indirectly cooling the battery cells 1 and other components inside the casing 2, which is beneficial to improving the overall safety of the battery pack. Furthermore, since the pressure relief channel 221, for example, is filled with cooling liquid, it can act as a kind of partition when the battery pack experiences thermal runaway. This prevents high-temperature flammable gases discharged from the first pressure relief component 110 of the battery cells 1 from directly contacting the oxygen outside the casing 2 before cooling down, thus avoiding safety issues such as fire. At the same time, the presence of cooling liquid can also pre-cool the high-temperature flammable gases before discharging them, further reducing the risk of fire and other safety issues, and improving the overall safety of the battery pack.

[0045] The cooling liquid can be a mixture of ethylene glycol and water. In the event of thermal runaway of the battery pack, such as when high-temperature flammable gas is released, a large amount of heat can cause the ethylene glycol to change from liquid to gas. During the vaporization process, it can absorb a large amount of heat, which can not only reduce the temperature of the high-temperature flammable gas, but also increase the pressure in the pressure relief channel 221. Thus, when the pressure in the pressure relief channel 221 exceeds the preset safety pressure, the pressure relief operation in the pressure relief channel 221 can be performed in advance, which helps to improve the safety of the entire battery pack.

[0046] It should be noted that, in order to ensure that the cooling liquid composed of ethylene glycol and water has a good cooling effect and improve the safety of the battery pack, in some embodiments, the percentage of ethylene glycol in the cooling liquid can be 50%-70%. This allows for the absorption of a large amount of heat during the process of more ethylene glycol changing from liquid to gas when, for example, the battery pack experiences thermal runaway and releases high-temperature flammable gas. This not only ensures a good cooling effect, but also generates more gas after vaporization, which is beneficial for rapidly increasing the pressure in, for example, the pressure relief channel 221. This facilitates the early pressure relief operation in the pressure relief channel 221 when the pressure exceeds the preset safety pressure, reducing the risk of thermal runaway and helping to improve the overall safety of the battery pack.

[0047] Of course, the specific embodiment where the ethylene glycol content percentage is 50%-70% is exemplary. Those skilled in the art can adapt it according to actual application needs. This disclosure does not make specific limitations in this regard. The purpose is to ensure that the coolant has a good cooling effect and helps improve the safety of the battery pack. In addition, the coolant can also be, for example, a glycerol-based coolant or a propylene glycol-based coolant. This disclosure is not limited to these. Those skilled in the art can choose any suitable coolant according to actual application needs. Of course, for better applicability, the coolant can be selected to remain liquid in low-temperature environments (e.g., below 0°C), thereby meeting the usage requirements of the battery pack in special environments such as low temperatures.

[0048] Taking the fluid medium 9 as a compressed gas as an example, the compressed gas can be, for example, an inert gas. Thus, by filling the pressure relief channel 221 with a certain pressure of inert gas, the structural strength and impact resistance of the casing 2 can be improved. Simultaneously, the gas in the pressure relief channel 221 can be completely replaced with the aforementioned inert gas, eliminating oxygen in the channel and reducing the risk of fire and other safety issues during battery pack thermal runaway, thereby improving the overall safety of the battery pack. Furthermore, since inert gases are chemically stable and have low thermal conductivity, they can effectively reduce heat transfer and convection to achieve thermal insulation, helping to extend the lifespan of individual battery cells 1 and further enhancing the overall safety of the battery pack.

[0049] For example, the inert gas may include at least one of, such as argon, xenon, and sulfur hexafluoride, to achieve the effect of heat insulation and reduce the risk of safety problems such as fire in the event of thermal runaway of the battery pack, thereby improving the overall safety of the battery pack. This disclosure is not limited thereto.

[0050] It should be noted that, since argon has the advantages of being chemically stable and having a higher density than air, it can significantly slow down the rate of heat transfer. Therefore, by filling argon at a certain pressure into, for example, the pressure relief channel 221, it is possible to achieve the effect of heat insulation and heat preservation, while also reducing the risk of safety issues such as fire during battery pack thermal runaway, thereby improving the overall safety of the battery pack.

[0051] In addition, since xenon has high density and heat insulation properties, as well as the advantages of chemical stability and good thermal insulation properties, by filling xenon with a certain pressure in, for example, the pressure relief channel 221, it is possible to achieve the effect of heat insulation and heat preservation, while also reducing the risk of safety problems such as fire during battery pack thermal runaway, and improving the overall safety of the battery pack.

[0052] In addition, since sulfur hexafluoride has the advantages of chemical stability, high electrical insulation performance and certain thermal insulation performance, by filling sulfur hexafluoride at a certain pressure in, for example, the pressure relief channel 221, it can also achieve the effect of heat insulation and heat preservation, while reducing the risk of safety problems such as fire during battery pack thermal runaway, and improving the overall safety of the battery pack.

[0053] Of course, the specific embodiment in which the compressed gas is an inert gas is exemplary. In other alternative embodiments, the compressed gas may also include chemically inert gases such as carbon dioxide, which are non-flammable and do not support combustion. The compressed gas may be a single gaseous substance filled in, for example, the pressure relief channel 221, or it may be a gas mixture. This disclosure does not make specific limitations in this regard. Those skilled in the art can select any suitable compressed gas according to actual application needs.

[0054] In some implementations, reference Figures 4 to 9 As shown, the pressure relief channel 221 may have a pressure relief port 240, and a pressure relief switch 250 is provided at the pressure relief port 240 to block the pressure relief port 240. The pressure relief switch 250 is configured to open the pressure relief port 240 when the battery cell 1 experiences thermal runaway, so that when the pressure in the pressure relief channel 221 exceeds the preset safety pressure, the pressure relief operation in the pressure relief channel 221 can be realized through the pressure relief port 240. The structure is simple and improves the safety of the battery pack.

[0055] In order to enable rapid pressure relief within the pressure relief channel 221, in some embodiments, reference is made to... Figure 7As shown, the number of pressure relief ports 240 can be arranged in multiple intervals to facilitate rapid pressure relief within the pressure relief channel 221 in the event of thermal runaway of, for example, a single battery cell 1, i.e., thermal runaway of the battery pack. This disclosure does not specifically limit the external outline, opening dimensions, number of ports, or spacing between adjacent ports 240; those skilled in the art can design them adaptively according to actual application requirements.

[0056] To reduce the possibility of the pressure relief switch 250 accidentally opening when the battery pack has not experienced thermal runaway, due to the pressure created by filling the pressure relief channel 221 with fluid medium 9, some embodiments may specify that the opening pressure of the pressure relief switch 250 is not less than the sum of a preset pressure and the pressure within the cavity 220 (pressure relief channel 221). This reduces the likelihood of the pressure relief switch 250 accidentally opening when the battery pack has not experienced thermal runaway, thereby improving the overall safety of the battery pack. It should be noted that when the pressure relief switch 250 includes, for example, a reinforcing plate 251, the opening pressure of the pressure relief switch 250 can be understood as the pressure required to detach the reinforcing plate 251 from the housing 2. When the pressure relief switch 250 includes a second pressure relief component such as an explosion-proof valve, a pressure relief valve, or a safety valve, the opening pressure of the pressure relief switch 250 can be understood as the opening pressure of the second pressure relief component.

[0057] Exemplarily, in some implementations, reference is made to Figures 4 to 9 As shown, the pressure relief switch 250 may include a reinforcing plate 251. The reinforcing plate 251 is detachably connected to the outer wall of the housing 2 and blocks the pressure relief port 240. For example, the reinforcing plate 251 may be connected to the outer wall of the second plate 262 (which will be described in detail below) away from the receiving groove 210 and block the pressure relief port 240. The structure is simple and easy to install and manufacture.

[0058] It should be noted that, since the reinforcing plate 251 is connected to the outer wall surface of the second plate 262 away from the receiving groove 210, the external force F1 generated during, for example, mechanical impact or bottom ball impact test of the battery pack (refer to...) Figure 9 When the reinforcing plate 251 (as shown) is applied, since the reinforcing plate 251 is sealed at the pressure relief port 240, the risk of the reinforcing plate 251 falling off due to the external force F1 can be effectively reduced, which helps to improve the reliability and safety of the battery pack. Furthermore, in cases such as thermal runaway of the battery pack, an external force F2 is generated inside the battery pack (see reference). Figure 9When the external force F2 acts on the reinforcing plate 251, and the external force F2 exceeds the connection force between the reinforcing plate 251 and the second plate 262 (this connection force can be, for example, adhesive force or clamping force), it is easy to detach the reinforcing plate 251 and realize the pressure relief operation in the pressure relief channel 221 through the pressure relief port 240. In this way, the arrangement of the reinforcing plate 251 not only ensures that the battery pack has high structural strength, but also facilitates the pressure relief operation in the case of thermal runaway of the battery pack, which helps to improve the reliability and safety of the battery pack, and is also conducive to the lightweight design of the battery pack.

[0059] For example, in some embodiments, the reinforcing plate 251 can be bonded to the housing 2, which is highly reliable and easy to install and arrange, and also helps to make the battery pack lightweight.

[0060] The connection strength (e.g., adhesive strength) between the reinforcing plate 251 and the housing 2 (second plate 262) is not less than 5 kPa. This ensures high connection reliability of the reinforcing plate 251 without affecting the pressure relief operation within the pressure relief channel 221 in the event of thermal runaway of the battery pack. This disclosure does not limit the connection strength between the reinforcing plate 251 and the housing 2 to this. Those skilled in the art can design it adaptively according to actual needs. The aim is to ensure that the reinforcing plate 251 can be stably connected to the housing 2 when the battery pack does not experience thermal runaway, and that after thermal runaway, the reinforcing plate 251 can be detached from the housing 2 under pressure within the pressure relief channel 221, thereby enabling the pressure relief operation of the pressure relief channel 221.

[0061] Of course, the specific embodiment in which the reinforcing plate 251 is bonded to the housing 2 is exemplary. In some alternative embodiments not shown, the reinforcing plate 251 can also be snapped to the housing 2 by, for example, a snap-fit ​​structure. In this way, after thermal runaway, when the pressure in the pressure relief channel 221 exceeds the snap-fit ​​force between the reinforcing plate 251 and the housing 2, the reinforcing plate 251 can be pushed open to achieve the purpose of pressure relief. This disclosure is not limited thereto, and those skilled in the art can adaptively design specific structural forms for the separable connection between the reinforcing plate 251 and the housing 2 according to actual application needs.

[0062] In addition, the aforementioned pressure relief switch 250 may also include a second pressure relief component, which may include, for example, an explosion-proof valve, a pressure relief valve, or a safety valve. This disclosure does not impose specific limitations on this component, and those skilled in the art can adapt it according to actual application requirements. The purpose is to enable pressure relief within the pressure relief channel 221 through the second pressure relief component after thermal runaway of the battery pack. This disclosure does not impose specific limitations on this component. It should be noted that the aforementioned pressure relief switch 250 may also include both a second pressure relief component and a reinforcing plate 251. That is, it can be understood that a reinforcing plate 251 or a second pressure relief component can be correspondingly provided at the corresponding pressure relief port 240 to achieve pressure relief operation of the battery pack.

[0063] To reduce the possibility that the second pressure relief component might accidentally open when the battery pack has not experienced thermal runaway, due to the pressure created by filling the pressure relief channel 221 with fluid medium 9, some embodiments may allow the opening pressure of the second pressure relief component to be no less than the sum of the first preset pressure and the pressure in the cavity 220 (pressure relief channel 221). This would reduce the possibility of the second pressure relief component accidentally opening when the battery pack has not experienced thermal runaway, thereby improving the overall safety of the battery pack.

[0064] It should be noted that the aforementioned first preset pressure may include, for example, the original opening pressure of an explosion-proof valve when the pressure relief channel is not filled with a fluid medium 9 at a certain pressure, as described in related technologies. Thus, this disclosure increases the opening pressure of the second pressure relief component by setting it to be no less than the sum of the first preset pressure and the pressure in the cavity 220 (pressure relief channel 221), thereby reducing the possibility of the second pressure relief component being accidentally opened when the battery pack has not experienced thermal runaway.

[0065] Alternatively, the first preset pressure may also include, for example, the original opening pressure of an explosion-proof valve when the pressure relief channel is not filled with a certain pressure fluid medium 9 in the related art, plus a certain margin (e.g., 1Kpa-5Kpa), which can also achieve the purpose of increasing the opening pressure of the second pressure relief component, thereby reducing the possibility of the second pressure relief component being opened erroneously when the battery pack does not experience thermal runaway.

[0066] For example, in some embodiments, the opening pressure of the second pressure relief component (the preset safety pressure within the pressure relief channel 221) can be, for example, 5 kPa-12 kPa. This disclosure is not limited thereto.

[0067] Exemplarily, in some implementations, reference is made to Figures 1 to 10As shown, the housing 2 may include a base plate 260, and a pressure relief channel 221 is disposed within the base plate 260. Thus, by filling the pressure relief channel 221 within the base plate 260 with a fluid medium 9, the structural strength and impact resistance of the base plate 260 can be improved. Furthermore, the high structural strength of the base plate 260 can better support the battery cell 1 and reduce the expansion of the battery cell 1, thereby reducing the capacity decay of the battery cell 1 and helping to ensure that the entire battery pack has high reliability and safety.

[0068] Additionally, in some implementations, references Figures 4 to 10 As shown, the base plate 260 may include a first direction (see reference). Figure 3 The first plate 261 and the second plate 262 are arranged opposite each other in the vertical direction of the middle plane (or the height direction of the battery pack, or the connection direction between the battery cell 1 of the battery pack and the base plate 260). A pressure relief channel 221 is formed between the first plate 261 and the second plate 262. The first plate 261 is provided with a connecting port 230, and the second plate 262 is provided with a pressure relief port 240, so as to realize the pressure relief operation stably through the pressure relief channel 221 in the base plate 260 in the event of, for example, thermal runaway of the battery pack.

[0069] In order to ensure a high degree of airtightness within the pressure relief channel 221, in some embodiments, the airtightness of the pressure relief channel 221 (cavity 220) is not less than 5 kPa, so as to ensure a high sealing effect, reduce the risk of leakage, and improve the reliability and safety of the entire battery pack.

[0070] This disclosure does not impose specific limitations on this, and those skilled in the art can adapt it according to actual needs. For example, the airtightness of the pressure relief channel 221 (cavity 220) can be constructed to be greater than the opening pressure of the second pressure relief component and / or the connection strength between the reinforcing plate 251 and the housing 2 (second plate 262), so that the pressure relief operation in the pressure relief channel 221 can be realized through the pressure relief switch 250 at the pressure relief port 240 after thermal runaway.

[0071] For example, to ensure the airtightness of the pressure relief channel 221, the first plate 261 and the second plate 262 forming the pressure relief channel 221 can be bonded together, for example, with sealant 10, to ensure a high degree of airtightness within the pressure relief channel 221 and avoid the risk of leakage. Furthermore, the spacing of the fastening bolts (not shown in the figure) connecting the first plate 261 and the second plate 262 can be adjusted to ensure a tight connection between the first plate 261 and the second plate 262, which helps to improve the airtightness of the pressure relief channel 221. For example, the spacing between two adjacent fastening bolts can be, for example, 80mm-120mm to ensure a tight connection between the first plate 261 and the second plate 262. This disclosure is not limited to this; those skilled in the art can adapt the spacing between two adjacent fastening bolts according to actual application requirements.

[0072] In addition, in some embodiments, the first plate 261 may include a support plate structure with a communication port 230. The support plate structure is used to support the battery cell 1 to provide support.

[0073] Alternatively, the first plate 261 may also include a liquid cooling plate structure with a communication port 230. The liquid cooling plate structure is used to cool the battery cells 1 and can also play a role in cooling down when the battery pack experiences thermal runaway. When the pressure relief channel 221 is filled with, for example, a cooling liquid, a double-layer cooling structure is formed, which is beneficial to improving the cooling effect and thus improving the reliability and safety of the battery pack.

[0074] Furthermore, in some implementations, references Figures 2 to 6 As shown, the base plate 260 may also be provided with an injection port 263 communicating with the pressure relief channel 221, for filling the pressure relief channel 221 with fluid medium 9 through the injection port 263. Furthermore, a one-way valve (not shown) or a sealing component (not shown) may be provided at the injection port 263 to avoid the risk of leakage.

[0075] Considering that in order to ensure that the battery cell 1 can be stably connected to the base plate 260 of the housing 2, in some embodiments, reference is made to... Figure 4 As shown, multiple battery cells 1 can be bonded to the top wall of the base plate 260 using adhesive 3, resulting in high reliability. The adhesive 3 can be a structural adhesive or a thermally conductive adhesive, etc., to ensure stable connection of the battery cells 1 to the base plate 260. Furthermore, when the adhesive 3 is, for example, a thermally conductive adhesive, it facilitates heat exchange between the first plate 261, which is constructed as, for example, a liquid-cooled plate structure, and the battery cells 1.

[0076] Additionally, in some implementations, references Figures 2 to 6As shown, a baffle structure 4 can be provided between the top wall of the base plate 260 and the battery cell 1. The baffle structure 4 forms a receiving channel 410 for accommodating the first pressure relief component 110 and communicating with the connecting port 230. The baffle structure 4 is used to block the first pressure relief component 110 and the adhesive 3. In this way, the baffle structure 4 can prevent the adhesive 3 from leaking into the pressure relief channel 221, which helps to improve the reliability of the battery pack.

[0077] In this disclosure, the specific structure of the adhesive barrier structure 4 is not specifically limited. For example, it can be constructed as adhesive barrier foam or adhesive barrier rubber block. For example, it can be a semi-rigid adhesive barrier foam or a semi-rigid adhesive barrier rubber block. This disclosure is not limited to this. Those skilled in the art can design it adaptively according to actual needs. The purpose is to achieve the purpose of blocking between the first pressure relief member 110 and the adhesive 3 through the adhesive barrier structure 4, so as to prevent the adhesive 3 from leaking into the pressure relief channel 221.

[0078] Furthermore, each receiving channel 410 can accommodate at least one first pressure relief element 110, exemplarily, such as Figure 5 As shown, the adhesive-blocking structures 4 can be arranged in multiple intervals along the second direction (referring to the length direction of the battery pack). Each adhesive-blocking structure 4 forms a receiving channel 410, and the receiving channel 410 can accommodate multiple connecting ports 230 arranged at intervals along the third direction (referring to the width direction of the battery pack), so that multiple first pressure relief components 110 connected to the corresponding connecting ports 230 can be simultaneously accommodated through each row of receiving channels 410. Of course, each row of receiving channels 410 can also be divided into multiple sub-channels (not shown) along the third direction. In this way, each sub-channel can be individually connected to the corresponding connecting port 230 and accommodate the first pressure relief component 110 on the corresponding battery cell 1. This disclosure is not limited to this.

[0079] In some implementations, reference Figure 10 As shown, a temperature sensing element 5 can be installed within the pressure relief channel 221. The temperature sensing element 5 is used to monitor the temperature of the fluid medium 9. For example, the temperature sensing element 5 can be a thermocouple, which has a simple structure and high accuracy, facilitating real-time or intermittent monitoring of the temperature of the fluid medium 9 over a preset time period. Furthermore, the temperature sensing element 5 may also include a heating resistance wire (not shown) installed within the pressure relief channel 221 to ensure that heating can be performed when the temperature of the fluid medium 9 is low.

[0080] Additionally, in some implementations, references Figure 10As shown, a drive structure 6 is provided in the pressure relief channel 221. The drive structure 6 is used to drive the fluid medium 9 to flow in the pressure relief channel 221. For example, the drive structure 6 can be a fan blade, so that the fluid medium 9 can be propelled to flow in the pressure relief channel 221 by the rotation of the fan blade. In this way, the fluid medium 9 is circulated in the pressure relief channel 221, which helps to ensure the uniform distribution of heat of the fluid medium 9 in the pressure relief channel 221 and helps to improve the cooling effect of the fluid medium 9, for example, constructed as a cooling liquid.

[0081] It should be noted that this disclosure does not specifically limit the specific structure of the temperature measuring element 5 and the driving structure 6, nor the connection method. Those skilled in the art can design them adaptively according to actual application requirements.

[0082] In some implementations, reference Figures 1 to 10 As shown, the housing 2 may also include a frame 270 disposed on the base plate 260. The base plate 260 and the frame 270 form a receiving groove 210 for accommodating multiple battery cells 1. Of course, it should be noted that in some embodiments not shown, the frame 270 of the housing 2 may also be provided with the aforementioned pressure relief channel 221. By filling the pressure relief channel 221 with fluid medium 9, the structural strength of the housing 2 and the impact resistance of the housing 2 can be improved, which helps to ensure that the entire battery pack has high reliability and safety.

[0083] Additionally, in some implementations, references Figures 1 to 3 As shown, the battery pack may also include a cover 7 that covers the housing 2 and closes the receiving groove 210. The cover 7 is connected to the housing 2 by a potting compound structure 8 formed by potting compound filled into the receiving groove 210. Thus, by filling the receiving groove 210 of the battery pack with potting compound, it helps to better connect the various components in the battery pack into a whole, effectively improves the overall structural strength of the battery pack and is conducive to the overall structural design of the pack, which helps to improve the insulation performance of the pack and the consistency of thermal management and thermal safety.

[0084] Considering the issue of reducing adhesive leakage into, for example, the pressure relief channel 221 during the potting operation, which could affect the potting effect and thus the gap between the battery pack cover 7 and the housing 2, in some embodiments, reference is made to... Figure 2 and Figure 3As shown, the potting compound structure 8 may include a first potting compound structure 810 and a second potting compound structure 820 connected to each other. The first potting compound structure 810 is arranged adjacent to the bottom plate 260 of the housing 2, and the second potting compound structure 820 is arranged adjacent to the cover 7. The first potting compound structure 810 is formed of non-foamed adhesive, and the second potting compound structure 820 is formed of foamed adhesive. In this way, by forming the first potting compound structure 810 with non-foamed adhesive, the gap between the bottom plate 260 and the battery cell 1 can be pre-sealed. The non-foamed adhesive has good flowability, which makes the filling effect between the battery cell 1 and the bottom plate 260 better. In addition, by filling with foamed adhesive to form the second potting compound structure 820, it is beneficial to the lightweight design of the battery pack. The combination of non-foamed adhesive and foamed adhesive for potting is beneficial to the structural design of the entire battery pack.

[0085] It should be noted that the aforementioned battery cell 1 can be constructed, for example, in the form of a battery cell, which is the smallest discharge power source in the battery device and includes positive and negative electrode separators and a battery cell casing, etc.

[0086] According to a second aspect of this disclosure, an electrical appliance is provided that includes the battery pack provided in the first aspect. This electrical appliance possesses all the beneficial effects of the battery pack provided in the first aspect, which will not be elaborated further herein.

[0087] In some exemplary application scenarios, the aforementioned electrical equipment can be a vehicle, wherein the vehicle can be a new energy vehicle, which can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc., and this disclosure does not make any specific limitations in this regard.

[0088] Of course, in other application scenarios, the above-mentioned electrical equipment can also be used for vehicles that need to be powered by battery packs, such as in the field of energy storage, aerospace or water transportation.

[0089] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0090] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0091] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A battery pack, characterized in that, include: Multiple battery cells; and The housing contains a plurality of battery cells disposed within it, and the housing has cavities within its walls, which are filled with a fluid medium.

2. The battery pack according to claim 1, characterized in that, The fluid medium is a liquid; The liquid is a cooling liquid.

3. The battery pack according to claim 2, characterized in that, The cooling liquid is a mixture of ethylene glycol and water; In the cooling liquid composed of the ethylene glycol and the water, the percentage of ethylene glycol is 50%-70%.

4. The battery pack according to claim 1, characterized in that, The fluid medium is compressed gas.

5. The battery pack according to claim 4, characterized in that, The compressed gas is an inert gas.

6. The battery pack according to claim 5, characterized in that, The inert gas includes at least one of argon, xenon, and sulfur hexafluoride.

7. The battery pack according to claim 4, characterized in that, The compressed gas includes carbon dioxide.

8. The battery pack according to claim 1, characterized in that, The fluid medium is configured such that the pressure inside the cavity is 1 kPa-3 kPa.

9. The battery pack according to claim 1, characterized in that, The airtightness of the cavity is not less than 5 kPa.

10. The battery pack according to any one of claims 1-9, characterized in that, The cavity includes a pressure relief channel, and the wall of the housing is provided with a first pressure relief component that connects the battery cell and the pressure relief channel.

11. The battery pack according to claim 10, characterized in that, The pressure relief channel has a pressure relief port, and a pressure relief switch is provided at the pressure relief port to block the pressure relief port. The pressure relief switch is configured to open the pressure relief port when the battery cell experiences thermal runaway.

12. The battery pack according to claim 11, characterized in that, The number of pressure relief ports is multiple and they are arranged at intervals.

13. The battery pack according to claim 11, characterized in that, The pressure relief switch includes a reinforcing plate, which is detachably connected to the outer wall of the housing and blocks the pressure relief port.

14. The battery pack according to claim 13, characterized in that, The reinforcing plate is bonded to the shell.

15. The battery pack according to claim 13, characterized in that, The connection strength between the reinforcing plate and the shell is not less than 5 kPa.

16. The battery pack according to claim 11, characterized in that, The opening pressure of the pressure relief switch is not less than the sum of the preset pressure and the pressure inside the cavity.

17. The battery pack according to any one of claims 11-16, characterized in that, The housing includes a base plate, and the pressure relief channel is disposed within the base plate.

18. The battery pack according to claim 17, characterized in that, The base plate is also provided with an injection port that communicates with the pressure relief channel, for filling the pressure relief channel with the fluid medium through the injection port.

19. The battery pack according to claim 17, characterized in that, Multiple battery cells are bonded to the top wall of the base plate with adhesive. An adhesive-blocking structure is provided between the top wall and the battery cells. The adhesive-blocking structure forms a receiving channel for accommodating the first pressure relief component and communicating with the communication port. The adhesive-blocking structure is used to block the first pressure relief component and the adhesive.

20. The battery pack according to claim 19, characterized in that, Each of the accommodating channels contains at least one of the first pressure relief components.

21. The battery pack according to claim 17, characterized in that, The base plate includes a first plate and a second plate arranged opposite to each other along a first direction, and the pressure relief channel is formed between the first plate and the second plate. The first plate is provided with the communication port, and the second plate is provided with the pressure relief port.

22. The battery pack according to claim 21, characterized in that, The first plate includes a support plate structure, on which the communication opening is provided, and the support plate structure is used to support the battery cell; or The first plate includes a liquid cooling plate structure, and the liquid cooling plate structure is provided with the communication port. The liquid cooling plate structure is used to cool the battery cell.

23. The battery pack according to claim 10, characterized in that, A temperature sensing element is installed in the pressure relief channel; the temperature sensing element is used to monitor the temperature of the fluid medium; and / or A driving structure is provided inside the pressure relief channel, and the driving structure is used to drive the fluid medium to flow inside the pressure relief channel.

24. The battery pack according to claim 1, characterized in that, The housing has a receiving groove for accommodating the plurality of battery cells, and the battery pack further includes a cover that covers the housing and closes the receiving groove. The cover is connected to the housing by a potting compound structure formed by potting compound filled into the receiving groove.

25. The battery pack according to claim 24, characterized in that, The potting compound structure includes a first potting compound structure and a second potting compound structure connected together. The first potting compound structure is arranged adjacent to the bottom plate of the shell, and the second potting compound structure is arranged adjacent to the cover. The first potting compound structure is formed of non-foaming adhesive, and the second potting compound structure is formed of foaming adhesive.

26. An electrical appliance, characterized in that, Includes the battery pack described in any one of claims 1-25.

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