Battery and electric equipment

Abstract

The utility model discloses a battery and an electric device. The battery comprises a box body; the single battery is arranged in the box body, and a first pressure relief mechanism is arranged on the first surface of the single battery; and the exhaust device is arranged in the box body, an exhaust channel is formed in the exhaust device, an air inlet communicated with the exhaust channel is formed in the exhaust device, and the air inlet and the first pressure relief mechanism are oppositely arranged. According to the technical scheme provided by the invention, the safety of the battery can be improved.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0003] Improving battery safety is a critical technical issue that urgently needs to be addressed in the development of battery technology. Summary of the Invention

[0004] This application provides a battery and an electrical device that can improve battery safety.

[0005] This application is achieved through the following technical solution:

[0006] In a first aspect, this application provides a battery, comprising: a housing; a battery cell disposed within the housing, wherein a first pressure relief mechanism is provided on a first surface of the battery cell; and an exhaust device disposed within the housing, wherein an exhaust channel is formed inside the exhaust device, and an air inlet communicating with the exhaust channel is provided on the exhaust device, wherein the air inlet is disposed opposite to the first pressure relief mechanism.

[0007] In the above scheme, when a battery cell experiences thermal runaway, a large amount of high-temperature gas is generated inside the battery cell due to chemical and electrochemical reactions. Under the pressure inside the battery cell, the high-temperature gas is discharged from the first pressure relief mechanism and enters the exhaust channel in the exhaust device. The exhaust channel restricts the flow of the high-temperature gas to avoid direct impact on the casing and to prevent the heat from the high-temperature gas on the wall from affecting adjacent battery cells. This reduces the risk of thermal spread of the battery and damage to the casing structure, effectively improving battery safety.

[0008] According to some embodiments of this application, the exhaust device has a first wall and a second wall disposed opposite to each other, the first wall being closer to the battery cell than the second wall, the air inlet being disposed on the first wall, the exhaust channel being formed between the first wall and the second wall, and the specific heat capacity of the first wall being greater than that of the second wall.

[0009] In the above scheme, by placing the first wall with a larger specific heat capacity closer to the battery cell, the heat discharged by the first pressure relief mechanism can be quickly absorbed, effectively reducing the impact of thermal runaway on adjacent battery cells.

[0010] According to some embodiments of this application, the specific heat capacity of the first wall is c, which satisfies c≥2KJ / (kg·℃).

[0011] In the above scheme, in order to reduce the impact of high temperature on adjacent battery cells after thermal runaway of a single battery cell, the specific heat capacity c of the first wall is greater than or equal to 2KJ / (kg·℃), so that the first wall can effectively absorb the heat generated by the thermal runaway of the battery cell. That is, by limiting the material of the first wall, the energy absorbed by the first wall (1kg) with a unit mass of temperature increase of 1℃ is at least 2KJ.

[0012] According to some embodiments of this application, c ≥ 3 KJ / (kg·℃).

[0013] In the above scheme, in order to effectively reduce the impact of high temperature on adjacent battery cells after thermal runaway of a single battery cell, the specific heat capacity c of the first wall is greater than or equal to 3KJ / (kg·℃), so that the first wall can effectively absorb the heat generated by the thermal runaway of the battery cell. That is, by limiting the material of the first wall, the energy absorbed by the first wall unit mass when the temperature rises by 1℃ is at least 3KJ.

[0014] According to some embodiments of this application, a receiving chamber is formed inside the first wall, the receiving chamber being used to receive a heat exchange medium to regulate the gas temperature in the exhaust channel.

[0015] In the above scheme, a receiving chamber is formed inside the first wall, and the receiving chamber can contain the heat exchange medium to effectively absorb the gas temperature in the exhaust channel, that is, effectively reduce the impact of the high temperature generated by the battery cell due to thermal runaway on the adjacent battery cells.

[0016] According to some embodiments of this application, the first wall has a medium inlet and a medium outlet, the medium inlet and the medium outlet respectively communicating with the receiving chamber.

[0017] In the above scheme, by setting a medium inlet and a medium outlet, the heat exchange medium can flow in the containment chamber, so that heat exchange medium that has not exchanged heat with the gas in the exhaust channel can be introduced into the containment chamber, and heat exchange medium that has exchanged heat with the gas in the exhaust channel can be discharged, ensuring the effect of temperature regulation of the gas in the exhaust channel, thereby effectively reducing the impact of the high temperature generated by the battery cell due to thermal runaway on adjacent battery cells.

[0018] According to some embodiments of this application, an adhesive layer is provided between the first wall and the first surface, and the battery cell is connected to the first wall through the adhesive layer. The thickness of the adhesive layer is D1, which satisfies 0.2mm≤D1≤5mm.

[0019] In the above scheme, the venting device can be fixed to the first surface of the battery cell by an adhesive layer. If the thickness of the adhesive layer is less than 0.2mm, the venting device cannot be effectively bonded to the surface of the battery cell, which may cause the venting device to detach from the battery cell, thus preventing the high-temperature gas discharged by the first pressure relief mechanism from entering the venting channel. If the thickness of the adhesive layer is greater than 5mm, it will affect the energy density of the battery and also affect the heat absorption effect of the first wall, thus reducing the safety of the battery. Therefore, in some embodiments of this application, the thickness D1 of the adhesive layer is limited to 0.2mm≤D1≤5mm, which can ensure that the battery has a high energy density and high safety while meeting the condition of stable connection between the venting device and the battery cell.

[0020] According to some embodiments of this application, the condition 0.5mm≤D1≤3mm is satisfied.

[0021] In the above scheme, the thickness D1 of the adhesive layer is limited to 0.5mm≤D1≤3mm, which allows the adhesive layer to have a suitable thickness so as to effectively connect the exhaust device and the battery cell, effectively ensure the heat absorption effect of the first wall, and ensure that the battery has a high energy density.

[0022] According to some embodiments of this application, the second wall is made of fire-resistant material.

[0023] In the above solution, by setting the second wall, made of fireproof material, to be farther away from the battery cells, it can withstand the direct impact of high-temperature gas and reduce the impact of high-temperature gas on the enclosure.

[0024] According to some embodiments of this application, the melting point of the second wall is P, which satisfies P≥600℃.

[0025] In the above scheme, when the temperature experienced by the second wall reaches its melting point, the physical state of the second wall changes, rendering it ineffective in providing fire protection. That is, when the high-temperature gas discharged from the first pressure relief mechanism acts on the second wall, if the temperature at which it acts on the second wall is higher than P, the second wall will melt, failing to prevent the high-temperature gas from reaching the exhaust device. Therefore, the melting point P of the second wall should have a high value, i.e., P ≥ 600℃, to effectively prevent the high-temperature gas from impacting the enclosure and causing damage.

[0026] According to some embodiments of this application, P ≥ 1500℃ is satisfied.

[0027] In the above scheme, if the second wall is made of a material with a melting point P greater than 1500℃, the second wall has excellent fire resistance and can effectively ensure the safety of the battery.

[0028] According to some embodiments of this application, the thickness of the second wall is D2, which satisfies 0.5mm≤D2≤5mm.

[0029] In the above scheme, the greater the thickness of the second wall, the better the fireproof effect of the second wall can be guaranteed, and the high-temperature gas will not damage the second wall and act on the box. However, the greater the thickness of the second wall, the more it will affect the energy density of the battery. Therefore, in some embodiments of this application, the thickness D2 of the second wall is limited to 0.5mm≤D2≤5mm, so that the battery has a higher energy density and a higher safety.

[0030] According to some embodiments of this application, the condition 0.7mm≤D2≤3mm is satisfied.

[0031] In the above scheme, in order to minimize the impact of the thickness of the second wall on the energy density of the battery and to maximize the safety of the battery, in some embodiments of this application, the thickness D2 of the second wall is limited to 0.7mm≤D2≤3mm.

[0032] According to some embodiments of this application, the thickness of the second wall is D2 in mm, and the melting point of the second wall is P in °C, satisfying 1500 ≤ D2 * P ≤ 3000.

[0033] In the above scheme, the fireproof effect of the second wall is related to its melting point and thickness. If its melting point is high, a thinner wall can achieve a certain fireproof effect. Similarly, if its melting point is low, the same fireproof effect can be achieved by increasing its thickness. The thickness of the second wall affects the energy density of the battery. Therefore, in some embodiments of this application, the balance between the fireproof effect and the battery energy density is maintained by multiplying the thickness D2 of the second wall by the melting point P of the second wall. That is, if D2*P is less than 1500, the fireproof effect is poor, and if D2*P ≥ 3000, it affects the battery energy density. Therefore, this application satisfies 1500 ≤ D2*P ≤ 3000 so that the second wall has a good fireproof effect without affecting the battery energy density.

[0034] According to some embodiments of this application, the impact strength of the second wall is E, which satisfies E≥20KJ / m 2 .

[0035] In the above scheme, if the impact resistance of the second wall is low, such as below 20KJ / m 2 However, there is a possibility that the second wall may be damaged due to the impact of high-temperature gases, thus reducing the fireproof effect. Therefore, in some embodiments of this application, the second wall meets the requirement of impact resistance strength E≥20KJ / m. 2 .

[0036] According to some embodiments of this application, E≥30KJ / m 2 .

[0037] In the above scheme, the impact resistance E of the second wall is greater than 30 KJ / m. 2 This effectively enables the second wall to resist the impact of high-temperature gases, ensuring the structural integrity of the second wall and thus guaranteeing its fireproof effect.

[0038] According to some embodiments of this application, the capacity of the battery cell is A, in ah; the distance between the first wall and the second wall is h, in mm; and satisfies 0.01≤h / A≤0.1.

[0039] In the above scheme, when a battery cell experiences thermal runaway, high-temperature gas is discharged through the first pressure relief mechanism. During the discharge process, the gas enters the exhaust channel through the inlet, and at least some of the high-temperature gas directly impacts the surface of the second wall facing the first wall. Due to the reaction, the velocity of the high-temperature gas decreases, and even backflow occurs, thereby affecting the exhaust efficiency of the battery cell. This results in the gas inside the battery cell not being discharged in a timely manner. The gap between the first and second walls can be considered as the exhaust gap. The smaller the gap between the first and second walls, the closer the second wall is to the first pressure relief mechanism. The smaller the exhaust gap, the greater the impact of the second wall on the exhaust efficiency of the battery cell. The more untimely the exhaust, the greater the risk of battery explosion. Conversely, the larger the gap between the first and second walls, the farther the second wall is from the first pressure relief mechanism. The larger the exhaust gap, the smaller the impact on exhaust efficiency. The more timely the exhaust, the lower the risk of battery explosion. At the same time, a larger gap between the first and second walls also affects the energy density of the battery.

[0040] Meanwhile, the larger the capacity A of a single battery cell, the more high-temperature gas is generated during thermal runaway, requiring a larger venting gap (the distance h between the first and second walls) to reduce the risk of battery explosion. Therefore, the distance h between the first and second walls and the capacity A of the single battery cell affect the battery's safety and energy density. Specifically, when h / A < 0.01, the venting gap is insufficient, and after thermal runaway, the high-temperature gas inside the battery cell cannot be discharged in time, causing the casing to rupture or even the battery to explode. When h / A > 0.1, the venting gap is too large, resulting in wasted internal space and affecting the battery's energy density. Therefore, the battery provided in this application satisfies 0.01 ≤ h / A ≤ 0.1, enabling the battery to have high energy density while maintaining high safety.

[0041] According to some embodiments of this application, the exhaust device further has a third wall disposed on the surface of the second wall opposite to the first wall, the third wall serving to support the second wall.

[0042] In some embodiments, the second wall can be made of a fire-resistant material with a softer texture and lower strength. Therefore, a third wall with higher strength is provided to support the second wall to improve the overall structural strength of the exhaust device, ensure that the exhaust device has a stable and non-deformable exhaust channel, and ensure effective guidance of high-temperature gas.

[0043] According to some embodiments of this application, the strength of the third wall is X, which satisfies X≥70MPa.

[0044] In the above scheme, if the strength of the third wall is not higher than 70MPa, it cannot effectively support the second wall. The exhaust device is easily deformed after being impacted, which may result in the exhaust channel being cut off or the diameter being reduced, affecting the exhaust of high-temperature gas and affecting the safety of the battery. Therefore, the third wall provided in this application satisfies X≥70MPa so that the third wall can effectively support the second wall.

[0045] According to some embodiments of this application, X ≥ 80 MPa is satisfied.

[0046] In the above scheme, X≥80MPa can effectively support the second wall of the third wall, ensuring the integrity of the second wall and the integrity of the exhaust channel, thereby making the battery have high safety.

[0047] According to some embodiments of this application, the thickness of the third wall is D3, which satisfies 0.3mm≤D3≤4mm.

[0048] In the above scheme, if the thickness of the third wall is greater, such as greater than 4mm, it can withstand greater impact, but it affects the energy density of the battery. If the thickness of the third wall is smaller, such as less than 0.3mm, it can improve the energy density of the battery, but it can withstand less impact. Therefore, in some embodiments of this application, the thickness D3 of the third wall satisfies 0.3mm≤D3≤4mm, so as to withstand greater impact while ensuring the energy density of the battery cell.

[0049] According to some embodiments of this application, the condition 0.5mm≤D3≤3mm is satisfied.

[0050] In the above scheme, the thickness D3 of the third wall satisfies 0.5mm≤D3≤3mm, so as to withstand a certain impact while ensuring the energy density of the battery cells as much as possible. This allows the exhaust device to smoothly guide the high-temperature gas, reduce the risk of heat spread in the battery and damage to the casing structure, and effectively improve the safety of the battery.

[0051] According to some embodiments of this application, the thickness of the third wall is D3 in mm, and the strength of the third wall is X in MPa, satisfying 100≤D3*X≤500.

[0052] In the above scheme, the support and impact resistance of the third wall are related to its strength and thickness. If its strength is high, a certain support and impact resistance effect can be achieved with a thinner thickness. Similarly, if its strength is low, the same support and impact resistance effect can be achieved by increasing its thickness. The thickness of the third wall affects the energy density of the battery. Therefore, in some embodiments of this application, the balance between the support and impact resistance effect and the battery energy density is maintained by multiplying the thickness D3 of the third wall by the melting point X of the third wall. That is, if D3*X is less than 100, its support and impact resistance effect is poor. If D2*P≥500, it affects the battery energy density. Therefore, this application satisfies 100≤D2*P≤500 so that the third wall has a good support and impact resistance effect without affecting the battery energy density.

[0053] According to some embodiments of this application, 140≤D3*X≤240 is satisfied.

[0054] In the above scheme, the third wall satisfies 140≤D3*X≤240, which makes the third wall have excellent support and impact resistance, and ensures that the battery has a high energy density.

[0055] According to some embodiments of this application, the thickness of the second wall is D2, and the thickness of the third wall is D3, satisfying 1mm≤D2+D3≤10mm.

[0056] In the above scheme, the sum of the thicknesses of the second and third walls affects the energy density of the battery, the fire resistance of the exhaust device, and the overall structural strength of the exhaust device. If the sum of the thicknesses of the second and third walls is greater than 10 mm, the energy density of the battery will decrease. If the sum of the thicknesses of the second and third walls is less than 1 mm, the fire resistance of the exhaust device and the overall structural strength of the exhaust device will decrease. Therefore, in some embodiments of this application, the sum of the thicknesses of the second wall D2 and the third wall D4 satisfies 1 mm ≤ D2 + D3 ≤ 10 mm, so that the exhaust device has a better fire resistance and higher structural strength under the condition that the battery has a higher energy density.

[0057] According to some embodiments of this application, 2mm≤D2+D3≤7mm is satisfied.

[0058] In the above scheme, the third wall and the second wall satisfy 2mm≤D2+D3≤7mm, which makes the exhaust device have better fire resistance and higher structural strength under the condition that the battery has a high energy density.

[0059] According to some embodiments of this application, the number of battery cells is multiple, and the multiple battery cells are stacked on top of each other; the exhaust device has multiple air inlets, and the multiple air inlets are distributed at intervals along the stacking direction of the battery cells to correspond one-to-one with the first pressure relief mechanism of the battery cells.

[0060] In the above solution, by setting multiple air inlets to correspond to the first pressure relief mechanism of multiple battery cells in the battery, it is ensured that the high-temperature gas discharged from the thermal runaway of any battery cell can enter the exhaust channel, thereby avoiding the impact of high-temperature gas on the casing and affecting adjacent battery cells, reducing the risk of battery thermal spread and casing structure damage, and effectively improving battery safety.

[0061] According to some embodiments of this application, the exhaust device has an exhaust port communicating with the exhaust channel, and the exhaust port is connected to the outside of the housing.

[0062] In the above scheme, the exhaust port of the exhaust device is connected to the outside of the box, thereby effectively venting the high-temperature gas generated inside the battery to the outside, avoiding the accumulation of heat inside the box and affecting the individual battery cells inside the battery.

[0063] According to some embodiments of this application, the wall of the housing is provided with a second pressure relief mechanism, and the exhaust device has an exhaust port communicating with the exhaust channel. The exhaust port is located inside the housing and is disposed towards the second pressure relief mechanism.

[0064] In the above scheme, the high-temperature gas is discharged through the exhaust port of the exhaust device. As the pressure inside the box increases, the second pressure relief mechanism is activated to discharge the high-temperature gas inside the box, ensuring the safety of the battery.

[0065] Secondly, this application also provides an electrical device, including the battery provided in the first aspect, the battery being used to provide electrical energy.

[0066] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0067] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0068] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0069] Figure 2 This is a schematic diagram of a battery in some embodiments of this application;

[0070] Figure 3 This is a schematic diagram of a battery cell and an exhaust device in some embodiments of this application;

[0071] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0072] Figure 5 This is a perspective view of a battery cell and an exhaust device in some embodiments of this application;

[0073] Figure 6 This is a schematic diagram of the interior of the first wall in some embodiments of this application;

[0074] Figure 7 for Figure 5 Enlarged view of point B in the middle;

[0075] Figure 8 This is a three-dimensional schematic diagram of the exhaust device and multiple battery cells in some embodiments of this application;

[0076] Figure 9 This is a schematic diagram of an exhaust device and multiple battery cells in some embodiments of this application.

[0077] Icons: 10-Box body; 11-First box body; 12-Second box body; 13-Second pressure relief mechanism; 20-Battery cell; 21-First surface; 22-First pressure relief mechanism; 23-Electrode terminal; 30-Exhaust device; 31-Exhaust channel; 32-Air inlet; 33-First wall; 330-Receiving chamber; 331-Medium inlet; 332-Medium outlet; 34-Second wall; 35-Adhesive layer; 36-Third wall; 360-Through hole;

[0078] 1000 - Vehicle; 100 - Battery; 200 - Controller; 300 - Motor. Detailed Implementation

[0079] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0080] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0081] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0082] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0083] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0084] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0085] In the description of the embodiments of this application, the technical terms "length", "width", "thickness", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0086] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0087] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include one or more battery cells. A battery generally includes a housing for encapsulating one or more batteries. The housing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0088] A single battery cell includes a casing, a first pressure relief mechanism, electrode terminals, an electrode assembly, and an electrolyte. The electrode assembly and electrolyte are located inside the casing, while the first pressure relief mechanism is located on the surface of the casing. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode terminals. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). The electrode terminals are located in the casing and electrically connected to the tabs of the electrode assembly for inputting or outputting electrical energy from the battery cell.

[0089] The first pressure relief mechanism refers to a component or part that is activated to release internal pressure or temperature when the internal pressure or temperature of a battery cell reaches a threshold. The first pressure relief mechanism can take the form of an explosion-proof valve, a gas valve, a pressure relief valve, or a safety valve, and can specifically adopt a pressure-sensitive or temperature-sensitive component or structure. That is, when the internal pressure or temperature of the battery cell reaches the threshold, the first pressure relief mechanism is activated or a weak structure in the first pressure relief mechanism is destroyed, thereby forming an opening or channel for the release of internal pressure or temperature.

[0090] The term "actuation" as used in this application refers to the activation or actuation of the first pressure relief mechanism to a certain state, thereby releasing the internal pressure and temperature of the battery cell. The action of the first pressure relief mechanism may include, but is not limited to, at least a portion thereof rupturing, breaking, tearing, or opening. When the first pressure relief mechanism is actuated, the high-temperature, high-pressure gas inside the battery cell is discharged from the actuated portion. This method enables pressure and temperature relief of the battery cell under controllable pressure or temperature, thereby preventing potentially more serious accidents.

[0091] The battery casing can be equipped with a second pressure relief mechanism. The working principle of the second pressure relief mechanism is the same as that of the first pressure relief mechanism. The second pressure relief mechanism can be an element or component that is actuated to release the internal pressure or temperature when the internal pressure or temperature of the battery reaches a threshold. The second pressure relief mechanism can take the form of an explosion-proof valve, a gas valve, a pressure relief valve, or a safety valve, and can specifically adopt pressure-sensitive or temperature-sensitive elements or structures.

[0092] The development of battery technology must consider multiple design factors simultaneously, such as performance parameters like energy density, discharge capacity, and charge / discharge rate. Additionally, battery safety must also be considered. Therefore, ensuring high battery safety is a pressing technical problem that needs to be solved.

[0093] The inventors discovered that a primary pressure relief mechanism is typically installed to release the high-temperature gas inside the battery cells, preventing potentially more serious safety accidents such as explosions and thus improving battery safety. However, despite the presence of this mechanism, the risk of battery safety issues due to thermal runaway remains high. Further research revealed that one reason for this is that the high-temperature gas generated by thermal runaway in the battery cells, when released through the primary pressure relief mechanism, directly impacts the battery casing, potentially causing damage or even melting. Furthermore, the heat from the gas can spread to adjacent battery cells, leading to thermal propagation and ultimately posing a safety risk.

[0094] In view of this, in order to improve the safety of the battery, the inventors conducted in-depth research and designed a battery that includes an exhaust device with an exhaust channel inside. The exhaust device is located inside the battery casing, and the air inlet of the exhaust device is opposite to the first pressure relief mechanism so that the high-temperature gas discharged by the first pressure relief mechanism can enter the exhaust channel.

[0095] In the above scheme, when a battery cell experiences thermal runaway, the high-temperature gas generated by the chemical and electrochemical reactions is discharged through the first pressure relief mechanism and then enters the exhaust channel in the exhaust device. This prevents the high-temperature gas from directly impacting the casing and prevents the heat from spreading to adjacent battery cells, thus reducing the risk of damage to the casing structure and thermal spread, and effectively improving battery safety.

[0096] The battery cells disclosed in this application can be used, but are not limited to, in electrical equipment such as vehicles, ships, or aircraft. A power system for such electrical equipment can be constructed using battery cells and batteries disclosed in this application.

[0097] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric bicycles, electric motorcycles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0098] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0099] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000's electrical system, such as meeting the power requirements for starting, navigation, and operation of the vehicle 1000.

[0100] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0101] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0102] According to some embodiments of this application, please refer to Figures 2-4 , Figure 2 This is a schematic diagram of the battery 100 in some embodiments of this application. Figure 3 This is a schematic diagram of the battery cell 20 and the exhaust device 30 in some embodiments of this application. Figure 4 for Figure 3 Enlarged view of point A in the middle.

[0103] The battery 100 includes a housing 10, battery cells 20, and an exhaust device 30. The battery cells 20 are disposed inside the housing 10, and a first pressure relief mechanism 22 is provided on the first surface 21 of the battery cells 20. The exhaust device 30 is disposed inside the housing 10, and an exhaust channel 31 is formed inside the exhaust device 30. An air inlet 32 ​​communicating with the exhaust channel 31 is provided on the exhaust device 30, and the air inlet 32 ​​is disposed opposite to the first pressure relief mechanism 22.

[0104] The housing 10 includes a first housing 11 and a second housing 12, which, when closed together, form a battery cavity in which multiple battery cells 20 are placed. The shapes of the first housing 11 and the second housing 12 can be determined based on the combined shape of the multiple battery cells 20. See also... Figure 2 The first housing 11 may be plate-shaped, and the second housing 12 has an opening on the side facing the first housing 11, with the first housing 11 covering the opening. In some embodiments, both the first housing 11 and the second housing 12 may have one opening. For example, both the first housing 11 and the second housing 12 may be hollow cuboids with only one opening on each side. The openings of the first housing 11 and the second housing 12 are opposite to each other, and the first housing 11 and the second housing 12 are interlocked to form a housing 10 with a closed cavity. Multiple battery cells 20 are connected in parallel, series, or mixed, or stacked and placed inside the housing 10 formed by the interlocking of the first housing 11 and the second housing 12.

[0105] The first surface 21 of the battery cell 20 is provided with a first pressure relief mechanism 22. When the battery cell 20 experiences thermal runaway, high-temperature gas is discharged through the first pressure relief mechanism 22 on the first surface 21. In some embodiments, the first surface 21 of the battery cell 20 can be the bottom surface, top surface, or side surface of the battery cell 20. See also Figure 3 The electrode terminals 23 of the battery cell 20 are disposed on the top surface of the battery cell 20, and the first pressure relief mechanism 22 is disposed on the bottom surface of the battery cell 20.

[0106] "The air inlet 32 ​​is positioned opposite to the first pressure relief mechanism 22" means that when the first pressure relief mechanism 22 is activated, the high-temperature gas discharged can directly enter the exhaust channel 31 through the air inlet 32, which can prevent the high-temperature gas from directly acting on the housing 10 and affecting the adjacent battery cells 20.

[0107] In the above scheme, when the battery cell 20 experiences thermal runaway, a large amount of high-temperature gas is generated inside the battery cell 20 due to chemical and electrochemical reactions. Under the pressure inside the battery cell 20, the high-temperature gas is discharged from the first pressure relief mechanism 22 and enters the exhaust channel 31 in the exhaust device 30. By restricting the flow of the high-temperature gas through the exhaust device 30, it is possible to avoid the high-temperature gas directly impacting the housing 10 and to avoid the heat of the high-temperature gas affecting adjacent battery cells 20, thereby reducing the risk of thermal spread of the battery 100 and damage to the structure of the housing 10, and effectively improving the safety of the battery 100.

[0108] According to some embodiments of this application, please refer to Figure 4 The exhaust device 30 has a first wall 33 and a second wall 34 arranged opposite to each other. The first wall 33 is closer to the battery cell 20 than the second wall 34. The air inlet 32 ​​is arranged on the first wall 33. An exhaust channel 31 is formed between the first wall 33 and the second wall 34. The specific heat capacity of the first wall 33 is greater than that of the second wall 34.

[0109] The first wall 33 is closer to the first surface 21 of the battery cell 20 than the second wall 34, so the high-temperature gas discharged by the first pressure relief mechanism 22 of the battery cell 20 can directly impact the surface of the second wall 34 facing the first wall 33.

[0110] Specific heat capacity, also known as specific heat capacity, is the heat capacity per unit mass of a substance, that is, the amount of heat absorbed by a unit mass of an object when its temperature changes by one unit. For example, the specific heat capacity of the first wall 33 refers to the amount of heat absorbed by a unit mass of the first wall 33 when its temperature changes.

[0111] "The specific heat capacity of the first wall 33 is greater than that of the second wall 34" can mean that the first wall 33 absorbs more heat when its temperature rises by 1°C per unit mass than the second wall 34 absorbs more heat when its temperature rises by 1°C per unit mass. In other words, the first wall 33 has a better heat absorption capacity than the second wall 34.

[0112] In some embodiments, the first wall 33 may be made of a high specific heat material such as magnesium oxide, zinc oxide, iron oxide, lead oxide, barium sulfate, asphalt, paraffin, calcium carbonate, or magnesium carbonate.

[0113] In the above scheme, by placing the first wall 33, which has a larger specific heat capacity, closer to the battery cell 20, the heat discharged by the first pressure relief mechanism 22 can be quickly absorbed, thereby effectively reducing the impact of thermal runaway on the adjacent battery cell 20.

[0114] According to some embodiments of this application, the specific heat capacity of the first wall 33 is c, which satisfies c≥2KJ / (kg·℃).

[0115] In some embodiments, the first wall 33 has a high specific heat capacity, which can be 2 KJ / (kg·℃), 2.5 KJ / (kg·℃), 3 KJ / (kg·℃), 3.5 KJ / (kg·℃), 4 KJ / (kg·℃), 4.5 KJ / (kg·℃) or higher.

[0116] In some embodiments, the specific heat capacity c of the first wall 33 can be measured by adiabatic calorimetry, water calorimetry, or gas constant pressure specific heat capacity determination method.

[0117] In the above scheme, in order to reduce the impact of high temperature on adjacent battery cells 20 after thermal runaway of battery cell 20, the specific heat capacity c of the first wall 33 is greater than or equal to 2KJ / (kg·℃), so that the first wall 33 can effectively absorb the heat generated by thermal runaway of battery cell 20. That is, by limiting the material of the first wall 33, the energy absorbed by the first wall 33 with a unit mass (1kg) temperature increase of 1℃ is at least 2KJ.

[0118] According to some embodiments of this application, c ≥ 3 KJ / (kg·℃).

[0119] In some embodiments, the first wall 33 has a higher specific heat capacity, which may be 3 KJ / (kg·℃), 3.5 KJ / (kg·℃), 4 KJ / (kg·℃), 4.5 KJ / (kg·℃) or higher.

[0120] In the above scheme, in order to effectively reduce the impact of high temperature on adjacent battery cells 20 after thermal runaway of battery cell 20, the specific heat capacity c of the first wall 33 is greater than or equal to 3KJ / (kg·℃), so that the first wall 33 can effectively absorb the heat generated by thermal runaway of battery cell 20. That is, by limiting the material of the first wall 33, the energy absorbed by the first wall 33 with a unit mass (1kg) temperature increase of 1℃ is at least 3KJ.

[0121] According to some embodiments of this application, please refer to Figures 5-7 , Figure 5 This is a perspective view of the battery cell 20 and the exhaust device 30 in some embodiments of this application. Figure 6 This is a schematic diagram of the interior of the first wall 33 in some embodiments of this application. Figure 7 for Figure 5 Enlarged view at point B. The interior of the first wall 33 forms a receiving chamber 330, which is used to receive the heat exchange medium to regulate the gas temperature in the exhaust passage 31.

[0122] The heat exchange medium can be a fluid (liquid or gas), and temperature regulation refers to absorbing heat from the high-temperature gas within the exhaust channel 31. Optionally, the fluid can be circulating to achieve better temperature regulation. Optionally, the fluid can be water, a mixture of water and ethylene glycol, or air, etc. In some embodiments, the first wall 33, due to the presence of a heat exchange medium inside, can also regulate the temperature of the battery cell 20, thereby cooling the battery cell 20. When the heat exchange medium is a coolant, the first wall 33 can be referred to as a water-cooled plate.

[0123] In the above scheme, the interior of the first wall 33 forms a receiving chamber 330, and the receiving chamber 330 can contain the heat exchange medium to effectively absorb the gas heat in the exhaust channel 31, that is, effectively reduce the impact of the high temperature generated by the battery cell 20 due to thermal runaway on the adjacent battery cell 20.

[0124] In some other embodiments, the first wall 33 may be a plate-like structure with a solid interior.

[0125] According to some embodiments of this application, please refer to Figure 5 and 7 The first wall 33 has a medium inlet 331 and a medium outlet 332, which are respectively connected to the receiving chamber 330.

[0126] In some embodiments, the medium inlet 331 and the medium outlet 332 are respectively disposed at two opposite ends in the extending direction of the first wall 33 to realize the flow of the heat exchange medium. In some embodiments, the medium inlet 331 and the medium outlet 332 can be connected to the thermal management system of the battery 100 through pipes. The thermal management system can provide the heat exchange medium through the pipes and the medium inlet 331, and the heat exchange medium in the first wall 33 can return to the thermal management system through the medium outlet 332 and the pipes.

[0127] In the above scheme, by setting the medium inlet 331 and the medium outlet 332, the heat exchange medium can flow in the receiving chamber 330, so that heat exchange medium that has not exchanged heat with the gas in the exhaust channel 31 can be introduced into the receiving chamber 330, and heat exchange medium that has exchanged heat with the gas in the exhaust channel 31 can be discharged, ensuring the effect of temperature regulation of the gas in the exhaust channel 31, thereby effectively reducing the impact of the high temperature generated by the battery cell 20 due to thermal runaway on the adjacent battery cells 20.

[0128] According to some embodiments of this application, an adhesive layer 35 is provided between the first wall 33 and the first surface 21, and the thickness of the adhesive layer 35 is D1, which satisfies 0.2mm≤D1≤5mm.

[0129] The adhesive layer 35 can refer to a component with adhesive properties, and the first wall 33 and the first surface 21 are connected to each other through the adhesive properties of the adhesive layer 35.

[0130] In some embodiments, the thickness D1 of the adhesive layer 35 can be 0.2 mm, 0.3 mm, 0.4 mm...4.7 mm, 4.8 mm, 4.9 mm or 5 mm.

[0131] In the above scheme, the exhaust device 30 can be fixed to the first surface 21 of the battery cell 20 by the adhesive layer 35. If the thickness of the adhesive layer 35 is less than 0.2 mm, the exhaust device 30 cannot be effectively bonded to the surface of the battery cell 20, which may cause the exhaust device 30 to detach from the battery cell 20, thus preventing the high-temperature gas discharged by the first pressure relief mechanism 22 from entering the exhaust channel 31. If the thickness of the adhesive layer 35 is greater than 5 mm, it will affect the energy density of the battery 100 and also affect the heat absorption effect of the first wall 33, thereby reducing the safety of the battery 100. Therefore, in some embodiments of this application, the thickness D1 of the adhesive layer 35 is limited to 0.2 mm ≤ D1 ≤ 5 mm, which can ensure that the battery 100 has a high energy density and high safety while satisfying the stable connection between the exhaust device 30 and the battery cell 20.

[0132] According to some embodiments of this application, the condition 0.5mm≤D1≤3mm is satisfied.

[0133] In some embodiments, the thickness D1 of the adhesive layer 35 can be 0.5 mm, 0.6 mm, 0.7 mm...2.7 mm, 2.8 mm, 2.9 mm or 3 mm.

[0134] In the above scheme, the thickness D1 of the adhesive layer 35 is limited to 0.5mm≤D1≤3mm, which enables the adhesive layer 35 to have a suitable thickness so as to effectively connect the exhaust device 30 and the battery cell 20, effectively ensure the heat absorption effect of the first wall 33, and at the same time ensure that the battery 100 has a high energy density.

[0135] According to some embodiments of this application, the second wall 34 is made of fire-resistant material.

[0136] The second wall 34 has good fire resistance, preventing the heat from the high-temperature gas from affecting the structural integrity of the enclosure 10. In some embodiments, the second wall 34 can be made of fire-resistant materials such as ceramic fiber, glass fiber, basalt fiber, rock wool, and alumina fiber.

[0137] In the above solution, the second wall 34, made of fire-resistant material, can withstand the direct impact of high-temperature gas, thereby reducing the impact of high-temperature gas on the housing 10.

[0138] According to some embodiments of this application, the melting point of the second wall 34 is P, which satisfies P≥600℃.

[0139] In some embodiments, the second wall 34 may be made of a fire-retardant material with a melting point of P, where P may be 600°C, 700°C, 800°C, 900°C…1500°C, 1600°C or a higher value.

[0140] In the above scheme, when the temperature experienced by the second wall 34 reaches its melting point, the physical state of the second wall 34 changes, and it fails to provide fire protection. That is, when the high-temperature gas discharged from the first pressure relief mechanism 22 acts on the second wall 34, if the temperature of the gas acting on the second wall 34 is higher than P, the second wall 34 will melt, failing to prevent the high-temperature gas from acting outside the exhaust device 30. Therefore, the melting point P of the second wall 34 should have a high value, i.e., P ≥ 600℃, to effectively prevent the high-temperature gas from impacting the housing 10 and causing damage to the housing 10.

[0141] According to some embodiments of this application, P ≥ 1500℃ is satisfied.

[0142] In some embodiments, the melting point P of the fireproof material used to make the second wall 34 can be 1500°C, 1550°C, 1600°C, 1650°C...1800°C or higher.

[0143] In the above scheme, if the second wall 34 is made of a material with a melting point P greater than 1500℃, the second wall 34 has excellent fireproof effect and can effectively ensure the safety of the battery 100.

[0144] According to some embodiments of this application, such as Figure 4 The thickness of the second wall 34 is D2, which satisfies 0.5mm≤D2≤5mm.

[0145] Along the direction from the first wall 33 to the second wall 34, the dimension of the second wall 34 is the thickness of the second wall 34, and the thickness D2 of the second wall 34 can be 0.5mm, 0.6mm, 0.7mm...3mm, 3.1mm...4.8mm, 4.9mm or 5mm.

[0146] In the above scheme, the greater the thickness of the second wall 34, the better the fireproof effect of the second wall 34 can be guaranteed, and the high temperature gas will not damage the second wall 34 and act on the box 10. However, the greater the thickness of the second wall 34, the more it will affect the energy density of the battery 100. Therefore, in some embodiments of this application, the thickness D2 of the second wall 34 is limited to 0.5mm≤D2≤5mm, so that the battery 100 has a higher energy density and higher safety.

[0147] According to some embodiments of this application, the condition 0.7mm≤D2≤3mm is satisfied.

[0148] In some embodiments, the thickness D2 of the second wall 34 can be 0.7mm, 0.8mm, 0.9mm…2mm, 2.1mm…2.8mm, 2.9mm or 3mm.

[0149] In the above scheme, in order to minimize the impact of the thickness of the second wall 34 on the energy density of the battery 100 and to maximize the safety of the battery 100, in some embodiments of this application, the thickness D2 of the second wall 34 is limited to 0.7mm≤D2≤3mm.

[0150] According to some embodiments of this application, the thickness of the second wall 34 is D2 (in mm), and the melting point of the second wall 34 is P (in °C), satisfying 1500≤D2*P≤3000.

[0151] D2*P refers to the product of the thickness D2 of the second wall 34 and the melting point P of the second wall 34. For example, when D2 is 3mm and P is 700℃, D2*P is 2100.

[0152] In the above scheme, the fireproof effect of the second wall 34 is related to its melting point and thickness. If its melting point is high, a thinner wall can achieve a certain fireproof effect; similarly, if its melting point is low, the same fireproof effect can be achieved by increasing its thickness. The thickness of the second wall 34 affects the energy density of the battery 100. Therefore, in some embodiments of this application, the balance between the fireproof effect and the energy density of the battery 100 is maintained by multiplying the thickness D2 of the second wall 34 by the melting point P of the second wall 34. That is, if D2*P is less than 1500, the fireproof effect is poor; if D2*P ≥ 3000, it affects the energy density of the battery 100. Therefore, this application satisfies 1500 ≤ D2*P ≤ 3000 to ensure that the second wall 34 has a good fireproof effect without affecting the energy density of the battery 100.

[0153] According to some embodiments of this application, the impact resistance strength of the second wall 34 is E, which satisfies E≥20KJ / m 2 .

[0154] Impact resistance refers to the ability of a unit area to resist impact force. The impact resistance E of the second wall 34 can be 20 kJ / m². 2 25KJ / m 2 30KJ / m 2 Or even higher values.

[0155] In some embodiments, the impact resistance of the second wall 34 can be measured by a drop hammer impact test.

[0156] In the above scheme, if the impact strength of the second wall 34 is low, such as below 20KJ / m2 However, there is a possibility that the second wall 34 may be damaged due to the impact of high-temperature gases, thus reducing the fireproof effect. Therefore, in some embodiments of this application, the second wall 34 satisfies the requirement of an impact resistance strength E≥20KJ / m2.

[0157] According to some embodiments of this application, E≥30KJ / m 2 .

[0158] In some embodiments, the impact strength E of the second wall 34 can be 30 KJ / m. 2 31KJ / m 2 32KJ / m 2 Or even higher values.

[0159] In the above scheme, the impact resistance E of the second wall 34 is greater than 30 KJ / m. 2 This effectively enables the second wall 34 to resist the impact of high-temperature gases, ensuring the structural integrity of the second wall 34 and thus guaranteeing its fireproof effect.

[0160] According to some embodiments of this application, the capacity of the battery cell 20 is A, measured in Ah. See also Figure 4 The distance between the first wall 33 and the second wall 34 is h, in mm. It satisfies 0.01 ≤ h / A ≤ 0.1.

[0161] Battery cell capacity is one of the important performance indicators for measuring battery cell performance. It represents the amount of electricity released by a battery cell under certain conditions (discharge rate, temperature, termination voltage, etc.) (discharge test can be performed using JS-150D).

[0162] The distance h between the first wall 33 and the second wall 34 can refer to the distance between the surface of the first wall 33 facing the second wall 34 and the surface of the second wall 34 facing the first wall 33 in the direction from the first wall 33 to the second wall 34.

[0163] In some embodiments, h / A can be 0.01, 0.02, 0.03, 0.04…0.08, 0.09 or 0.1.

[0164] In the above scheme, when the battery cell 20 experiences thermal runaway, the high-temperature gas will be discharged by the first pressure relief mechanism 22. During the discharge process, the gas enters the exhaust channel 31 through the air inlet 32. At least part of the high-temperature gas will directly impact the surface of the second wall 34 facing the first wall 33, causing the high-temperature gas velocity to decrease or even cause backflow, thereby affecting the exhaust efficiency of the battery cell 20 and causing the gas inside the battery cell 20 to be discharged in a timely manner. The gap between the first wall 33 and the second wall 34 can be considered as the venting gap. The smaller the gap between the first wall 33 and the second wall 34, the closer the second wall 34 is to the first pressure relief mechanism 22. The smaller the venting gap, the greater the impact of the second wall 34 on the venting efficiency of the battery cell 20. The more untimely the venting, the greater the risk of battery 100 explosion. Conversely, the larger the gap between the first wall 33 and the second wall 34, the farther the second wall 34 is from the first pressure relief mechanism 22. The larger the venting gap, the smaller the impact on venting efficiency. The more timely the venting, the lower the risk of battery 100 explosion. At the same time, the larger the gap between the first wall 33 and the second wall 34, the lower the energy density of battery 100.

[0165] Meanwhile, the larger the capacity A of the battery cell 20, the more high-temperature gas is generated when the battery cell 20 experiences thermal runaway, and the larger the required venting gap (the distance h between the first wall 33 and the second wall 34). Therefore, the distance h between the first wall 33 and the second wall 34 and the capacity A of the battery cell 20 affect the safety and energy density of the battery 100. Specifically, when h / A < 0.01, there is insufficient venting gap, and after thermal runaway of the battery cell 20, the high-temperature gas inside cannot be discharged in time, causing the casing of the battery cell 20 to crack or even the battery 100 to explode. When h / A > 0.1, there is excessive venting gap, resulting in wasted internal space of the battery 100 and affecting the energy density of the battery 100. Therefore, the battery 100 provided in this application can satisfy 0.01 ≤ h / A ≤ 0.1, so that the battery 100 has high energy density while maintaining high safety.

[0166] According to some embodiments of this application, please refer to Figure 3 and Figure 4 The exhaust device 30 also has a third wall 36, which is disposed on the surface of the second wall 34 opposite to the first wall 33, and the third wall 36 is used to support the second wall 34.

[0167] The third wall 36 has a higher structural strength than the second wall 34. The third wall 36 is disposed on the surface of the second wall 34 that is opposite to the first wall 33, so as to support the second wall 34. In some embodiments, the third wall 36 can be made of a high-strength material such as aluminum alloy, steel or plastic.

[0168] In some embodiments, the second wall 34 may be made of a softer fire-resistant material. For this purpose, a third wall 36 with higher strength is provided to support the second wall 34, thereby improving the overall structural strength of the exhaust device 30, ensuring that the exhaust device 30 has a stable and non-deformable exhaust channel 31, and ensuring effective guidance of high-temperature gas.

[0169] According to some embodiments of this application, the strength of the third wall 36 is X, which satisfies X≥70MPa.

[0170] Strength refers to the mechanical properties of an object in resisting fracture and excessive deformation. The strength X of the third wall 36 can be measured by applying a certain force to a unit area of ​​the third wall 36 using a dedicated strength tester.

[0171] In some embodiments, the strength of the third wall 36 can be 70 MPa, 75 MPa, 80 MPa or higher.

[0172] In the above scheme, if the strength of the third wall 36 is not higher than 70MPa, it cannot effectively support the second wall 34. The exhaust device 30 is easily deformed after impact, which may lead to the exhaust channel 31 being cut off or its diameter being reduced, affecting the exhaust of high-temperature gas and impacting the safety of the battery 100. Therefore, the third wall 36 provided in this application satisfies X≥70MPa, so that the third wall 36 can effectively support the second wall 34.

[0173] According to some embodiments of this application, X ≥ 80 MPa is satisfied.

[0174] In some embodiments, the strength of the third wall 36 can be 80 MPa, 85 MPa, 90 MPa or higher.

[0175] In the above scheme, X≥80MPa can effectively support the second wall 34 by the third wall 36, ensuring the integrity of the second wall 34 and the integrity of the exhaust channel 31, thereby making the battery 100 have high safety.

[0176] According to some embodiments of this application, see Figure 4 The thickness of the third wall 36 is D3, which satisfies 0.3mm≤D3≤4mm.

[0177] The thickness D3 of the third wall 36 can refer to the direction from the first wall 33 to the third wall 36, and the size of the third wall 36. In some embodiments, the thickness D3 of the third wall 36 can be 0.3mm, 0.4mm, 0.5mm...3.8mm, 3.9mm or 4mm.

[0178] In the above scheme, if the thickness of the third wall 36 is greater, such as greater than 4mm, it can withstand greater impact, but it affects the energy density of the battery 100; if the thickness of the third wall 36 is smaller, such as less than 0.3mm, it can increase the energy density of the battery 100, but it can withstand less impact. Therefore, in some embodiments of this application, the thickness D3 of the third wall 36 satisfies 0.3mm≤D3≤4mm, so as to withstand greater impact while ensuring the energy density of the battery cell 20.

[0179] According to some embodiments of this application, the condition 0.5mm≤D3≤3mm is satisfied.

[0180] In some embodiments, the thickness D3 of the third wall 36 can be 0.5mm, 0.6mm, 0.7mm...2.8mm, 2.9mm or 3mm.

[0181] In the above scheme, the thickness D3 of the third wall 36 satisfies 0.5mm≤D3≤3mm, so as to withstand a certain impact while ensuring the energy density of the battery cell 20 as much as possible, so that the exhaust device 30 can smoothly guide the high temperature gas, reduce the risk of heat spread of the battery 100 and damage to the structure of the casing 10, and effectively improve the safety of the battery 100.

[0182] According to some embodiments of this application, the thickness of the third wall 36 is D3 in mm, and the strength of the third wall 36 is X in MPa, satisfying 100≤D3*X≤500.

[0183] D3*X can refer to the product of the thickness D3 of the third wall 36 and the strength X of the third wall 36. For example, when D3 is 2mm and X is 70MPa, D3*X is 140.

[0184] In some embodiments, D3*X can be 100, 120, 140…490 or 500.

[0185] In the above scheme, the support and impact resistance of the third wall 36 are related to its strength and thickness. If its strength is high, a certain support and impact resistance effect can be achieved with a thinner thickness. Similarly, if its strength is low, the same support and impact resistance effect can be achieved by increasing its thickness. The thickness of the third wall 36 affects the energy density of the battery 100.

[0186] Therefore, in some embodiments of this application, the balance between the support and impact resistance and the energy density of the battery 100 is maintained by multiplying the thickness D3 of the third wall 36 by the melting point X of the third wall 36. That is, if D3*X is less than 100, the support and impact resistance is poor, and if D2*P ≥ 500, it affects the energy density of the battery 100. Therefore, this application satisfies 100 ≤ D2*P ≤ 500 so that the third wall 36 has a good support and impact resistance without affecting the energy density of the battery 100.

[0187] According to some embodiments of this application, 140≤D3*X≤240 is satisfied.

[0188] In some embodiments, D3*X can be 140, 150, 160…230 or 240.

[0189] In the above scheme, the third wall 36 satisfies 140≤D3*X≤240, which makes the third wall 36 have excellent support and impact resistance, and ensures that the battery 100 has a high energy density.

[0190] According to some embodiments of this application, such as Figure 4 The thickness of the second wall 34 is D2, and the thickness of the third wall 36 is D3, satisfying 1mm≤D2+D3≤10mm.

[0191] In some embodiments, D2+D3 can be 1mm, 2mm, 3mm...9mm or 10mm.

[0192] In the above scheme, the sum of the thicknesses of the second wall 34 and the third wall 36 affects the energy density of the battery 100, the fireproof effect of the exhaust device 30, and the overall structural strength of the exhaust device 30. If the sum of the thicknesses of the second wall 34 and the third wall 36 is greater than 10 mm, the energy density of the battery 100 will decrease. If the sum of the thicknesses of the second wall 34 and the third wall 36 is less than 1 mm, the fireproof effect and the overall structural strength of the exhaust device 30 will decrease. Therefore, in some embodiments of this application, the sum of the thicknesses of the second wall 34 and the third wall 36 satisfies 1 mm ≤ D2 + D3 ≤ 10 mm, so that under the condition that the battery 100 has a high energy density, the exhaust device 30 has a good fireproof effect and a high structural strength.

[0193] According to some embodiments of this application, 2mm≤D2+D3≤7mm is satisfied.

[0194] In some embodiments, D2+D3 can be 2mm, 3mm, 4mm...6mm or 7mm.

[0195] In the above scheme, the third wall 36 and the second wall 34 satisfy 2mm≤D2+D3≤7mm, so that the exhaust device 30 has better fire resistance and higher structural strength under the condition that the battery 100 has a high energy density.

[0196] In some embodiments, see Figure 7 The interior of the third wall 36 can be provided with weight-reducing holes to reduce the weight of the third wall 36, thereby increasing the energy density of the battery 100.

[0197] In some embodiments, the second wall 34 may be disposed on the third wall 36 by means of adhesive bonding, welding or snap-fitting.

[0198] In some embodiments, the two ends of the third wall 36 perpendicular to its extending direction can be connected to the first wall 33 so that the second wall 34 can enclose the exhaust passage 31 with the first wall 33. In other embodiments, the third wall 36 and the first wall 33 can be connected by a connector, the material of which can be the same as the material of the first wall 33 or the material of the third wall 36.

[0199] In some embodiments, the venting device 30 is connected to the first surface 21 of the battery cell 20 via an adhesive layer 35, thereby securing the venting device 30. In other embodiments, such as Figure 7 The third wall 36, perpendicular to the first surface 21, has a through hole 360. The wall is connected to the housing 10 by bolts passing through the through hole 360, which also enables the fixing of the exhaust device 30.

[0200] Based on some embodiments of this application, please refer to... Figure 5 , Figure 8 and Figure 9 , Figure 8 This is a perspective view of multiple battery cells 20 and an exhaust device 30 in some embodiments of this application. Figure 9 This is a schematic diagram of a plurality of battery cells 20 and an exhaust device 30 in some embodiments of this application.

[0201] There are multiple battery cells 20, which are stacked on top of each other. The exhaust device 30 has multiple air inlets 32, which are distributed at intervals along the stacking direction x of the battery cells 20 to correspond one-to-one with the first pressure relief mechanism 22 of the battery cells 20.

[0202] In some embodiments, a plurality of battery cells 20 may be arranged in the battery 100 along the stacking direction x, and the exhaust device 30 may be provided with a plurality of air inlets 32 corresponding to each first pressure relief mechanism 22. In some embodiments, two rows of battery cells 20 may be arranged along a first direction y perpendicular to the stacking direction x, for example, the first direction y may be the height direction of the battery 100. For this purpose, the exhaust device 30 may be provided with two rows of air inlets 32 corresponding to the first direction.

[0203] In some embodiments, the battery 100 has two rows of battery cells 20 arranged along a second direction z (the second direction z is perpendicular to the stacking direction x and the first direction y). Each row of battery cells 20 has two rows of battery cells 20 along the first direction y. An exhaust device 30 is disposed between the two rows of battery cells 20 and extends along the first direction. Figure 9 The structure of the exhaust device 30 along the second direction z can be a first wall 33, a second wall 34, a third wall 36, a second wall 34, and a first wall 33. That is, the exhaust device 30 can have two exhaust channels 31, which are arranged at intervals along the second direction z. Each first wall 33 is provided with an air inlet 32 ​​corresponding to the first pressure relief mechanism 22 of the battery cell 20.

[0204] In the above scheme, by setting multiple air inlets 32, each corresponding to the first pressure relief mechanism 22 of multiple battery cells 20 in the battery 100, it is ensured that the high-temperature gas discharged from the thermal runaway of any battery cell 20 can enter the exhaust channel 31, thereby avoiding the impact of high-temperature gas on the housing 10 and affecting adjacent battery cells 20, reducing the risk of thermal spread of the battery 100 and damage to the structure of the housing 10, and effectively improving the safety of the battery 100.

[0205] According to some other embodiments of this application, the exhaust device 30 has an exhaust port that communicates with the exhaust passage 31 and is connected to the outside of the housing 10.

[0206] In some other embodiments, the exhaust port of the exhaust device 30 is located at both ends or one end of the extension direction of the exhaust device 30, and the exhaust port is connected to the outside of the housing 10 so as to realize the discharge of high temperature gas in the exhaust channel 31 to the outside.

[0207] In the above scheme, the exhaust port of the exhaust device 30 is connected to the outside of the box 10, thereby effectively exhausting the high-temperature gas generated inside the battery 100 to the outside, avoiding the accumulation of heat inside the box 10 and affecting the battery cells 20 inside the battery 100.

[0208] According to some embodiments of this application, the wall of the housing 10 is provided with a second pressure relief mechanism 13, and the exhaust device 30 has an exhaust port communicating with the exhaust channel 31. The exhaust port is located inside the housing 10 and is disposed toward the second pressure relief mechanism 13.

[0209] like Figure 2 The wall of the housing 10 is provided with a second pressure relief mechanism 13. When a large amount of gas is accumulated in the housing 10 and discharged by the exhaust device 30, the second pressure relief mechanism 13 can be activated to discharge the gas.

[0210] In the above scheme, the high-temperature gas is discharged through the exhaust port of the exhaust device 30. As the pressure inside the housing 10 increases, the second pressure relief mechanism 13 is activated to discharge the high-temperature gas inside the housing 10, ensuring the safety of the battery 100.

[0211] According to some embodiments of this application, this application also provides an electrical device, which includes a battery 100 for increasing electrical energy.

[0212] According to some embodiments of this application, please refer to Figures 2-6 Some embodiments of this application provide a battery 100, which includes a housing 10, an exhaust device 30, and six rows of battery cells 20.

[0213] The wall of the housing 10 is provided with a second pressure relief mechanism 13, and the exhaust device 30 and the battery cell 20 are both located inside the housing 10.

[0214] Six rows of battery cells 20 are arranged at intervals along the second direction z. Each row of battery cells 20 includes two rows of battery cells 20 along the first direction y. Each row of battery cells 20 includes nine battery cells 20 stacked together along the stacking direction x.

[0215] There are three exhaust devices 30. The exhaust devices 30 are arranged between two adjacent rows of battery cells 20 and correspond to the first pressure relief mechanism 22 of each battery cell 20 in the two adjacent rows of battery cells 20.

[0216] Each battery cell 20 has a first pressure relief mechanism 22 on its first surface 21.

[0217] The exhaust device 30 has an exhaust channel 31 inside, and an air inlet 32 ​​communicating with the exhaust channel 31 is provided on the exhaust device 30. The air inlet 32 ​​is arranged opposite to the first pressure relief mechanism 22 of the corresponding battery cell 20. The high-temperature gas discharged by the first pressure relief mechanism 22 can enter the exhaust channel 31 through the corresponding air inlet 32 ​​to achieve directional pressure relief of the high-temperature gas, avoid the high-temperature gas directly impacting the housing 10, and avoid the heat of the high-temperature gas affecting the adjacent battery cell 20.

[0218] Along the thickness direction of the venting device 30, the venting device 30 includes a first wall 33, a second wall 34, and a third wall 36. The first wall 33 is connected to the first surface 21 of the battery cell 20 via an adhesive layer 35. The first wall 33 and the second wall 34 are spaced apart to form a venting channel 31, and the third wall 36 is disposed on the surface of the second wall 34 opposite to the first wall 33 to support the second wall 34. The first wall 33 has a high specific heat capacity. In some embodiments, the specific heat capacity of the first wall 33 is c, satisfying c≥2KJ / (kg·℃), and in other embodiments, the first wall 33 satisfies c≥2KJ / (kg·℃). In some embodiments, the first wall 33 can be bonded to the battery cell 20 by an adhesive layer 35 with a thickness of D1. In some embodiments, the adhesive layer 35 satisfies 0.2mm≤D1≤5mm. In other embodiments, the adhesive layer 35 satisfies 0.5mm≤D1≤3mm. See also Figure 7 The first wall 33 can be a water-cooled plate, that is, the interior of the first wall 33 forms a receiving chamber 330, which is used to receive the heat exchange medium. The heat exchange medium flows in and out through the medium inlet 331 and the medium outlet 332 on the first wall 33.

[0219] In other embodiments, see Figure 8 The first wall 33 can be a plate-like structure.

[0220] The second wall 34 is made of fire-resistant material, and its melting point P should be greater than or equal to 600°C. In some embodiments, the melting point P of the second wall 34 can be greater than or equal to 1500°C. In some embodiments, the thickness of the second wall 34 is D2 (in mm), and the melting point P (in °C) of the second wall 34 satisfies 1500 ≤ D2 * P ≤ 3000. In some embodiments, the thickness D2 of the second wall 34 satisfies 0.5 mm ≤ D2 ≤ 5 mm.

[0221] The impact strength of the second wall 34 is E, which satisfies E≥20KJ / m 2 To ensure the safety of the second wall 34, the second wall 34 can also be made of material with an impact resistance greater than or equal to 30 KJ / m. 2 The material is used to make it. To ensure the smooth discharge of high-temperature gas, when the capacity of the battery cell 20 is A, the unit is ah; when the distance between the first wall 33 and the second wall 34 is h, the unit is mm; the battery 100 satisfies 0.01≤h / A≤0.1.

[0222] The third wall 36 is a high-strength structure. Generally, the third wall 36 can be made of a material with a strength greater than or equal to 70 MPa. To further improve the strength of the third wall 36, it can also be made of a material with a strength greater than or equal to 80 MPa. In some embodiments, to balance the energy density of the battery 100 and the support of the third wall 36, when the thickness of the third wall 36 is D3 (in mm) and the strength of the third wall 36 is X (in MPa), the third wall 36 satisfies 100 ≤ D3 * X ≤ 500. In some embodiments, the third wall 36 satisfies 140 ≤ D3 * X ≤ 240.

[0223] In some embodiments, the second wall 34 and the third wall 36 satisfy 1mm ≤ D2 + D3 ≤ 10mm. In other embodiments, the second wall 34 and the third wall 36 satisfy 2mm ≤ D2 + D3 ≤ 7mm.

[0224] The inventors used the specific heat capacity of the first wall (c), the melting point of the second wall (P), the thickness of the second wall (D2), the impact strength of the second wall (E), the distance between the first and second walls (h), and the capacity of the battery cell (A) as variables for the battery and the battery cells within it. They then subjected one of the battery cells to thermal runaway treatment (making its heat generation efficiency higher than its heat dissipation efficiency) and conducted multiple experiments to demonstrate that the battery provided in some embodiments of this application has high safety. The experimental results are shown in Table 1.

[0225] Table 1

[0226]

[0227] As shown in Table 1, when c ≥ 2 KJ / (kg·℃), P ≥ 600℃, D2 ≥ 0.5 mm, 1500 ≤ D2 * P, E ≥ 20 KJ / m 2 When h / A≥0.01, after a single battery cell causes thermal runaway due to abuse, it only smokes and does not catch fire. Its thermal shock and heat transfer will not cause adjacent battery cells to fail, thus ensuring that the entire battery will not experience thermal diffusion and ensuring battery safety.

[0228] When c < 2 KJ / (kg·℃), a single battery cell will catch fire after thermal runaway. Its heat transfer will cause adjacent battery cells to fail, which in turn will cause the battery to catch fire.

[0229] When D2*P < 1500 or h / A < 0.01, after thermal runaway of a single battery cell, its thermal shock will cause adjacent battery cells to fail, which in turn will lead to thermal diffusion and cause the battery to catch fire.

[0230] When D2 > 5mm, D2*P > 3000, or h / A > 0.1, the energy density of the battery will decrease due to over-design for safety.

[0231] The inventors used the strength X and thickness D3 of the third wall as battery variables to conduct vibration frequency tests on the battery, performing multiple experiments to demonstrate that the battery provided in some embodiments of this application has high safety. The experimental results are shown in Table 2.

[0232] Table 2

[0233]

[0234] The third wall serves to support and ensure the stability and strength of the exhaust system. Table 2 shows that when X ≥ 70 MPa, D3 ≥ 0.5 mm, and 100 ≤ D3*X ≤ 3000, the dominant vibration frequency meets the vehicle's requirements, ensuring the exhaust system effectively guides high-temperature gas and thus providing high battery safety. When D3*X < 100, the support structure is weak and cannot meet the vibration intensity requirements of vehicle conditions, leading to exhaust failure and potential safety risks. When D3*X > 3000, although the support structure's strength meets the vibration intensity requirements of vehicle conditions, it occupies more space or significantly increases material costs, resulting in over-design and waste.

[0235] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery, characterized by, The battery comprises: a box body; a battery cell arranged in the box body, a first surface of the battery cell being provided with a first pressure relief mechanism; an exhaust device arranged in the box body, an exhaust passage being formed in the exhaust device, and an air inlet being arranged on the exhaust device and communicating with the exhaust passage, the air inlet being arranged opposite to the first pressure relief mechanism; the exhaust device has a first wall and a second wall arranged opposite to each other, the first wall being closer to the battery cell than the second wall, the air inlet being arranged on the first wall, the exhaust passage being formed between the first wall and the second wall, and the specific heat capacity of the first wall being greater than that of the second wall.

2. The battery according to claim 1, wherein the specific heat capacity of the first wall is c, and c≥2 KJ / (kg·℃).

3. The battery according to claim 2, wherein c≥3 KJ / (kg·℃).

4. The battery according to claim 1, wherein an accommodation cavity is formed in the first wall, and the accommodation cavity is used to accommodate a heat exchange medium to adjust the temperature of the gas in the exhaust passage.

5. The battery according to claim 4, wherein the first wall has a medium inlet and a medium outlet, and the medium inlet and the medium outlet respectively communicate with the accommodation cavity.

6. The battery according to claim 1, wherein an adhesive layer is arranged between the first wall and the first surface, the battery cell is connected to the first wall through the adhesive layer, the thickness of the adhesive layer is D1, and 0.2 mm≤D1≤5 mm.

7. The battery according to claim 6, wherein 0.5 mm≤D1≤3 mm.

8. The battery according to claim 1, wherein the second wall is made of a fireproof material.

9. The battery according to claim 8, wherein the melting point of the second wall is P, and P≥600 ℃.

10. The battery according to claim 9, wherein P≥1500 ℃.

11. The battery according to claim 8, wherein the thickness of the second wall is D2, and 0.5 mm≤D2≤5 mm.

12. The battery according to claim 11, wherein 0.7 mm≤D2≤3 mm.

13. The battery according to claim 8, wherein the thickness of the second wall is D2 (unit: mm), the melting point of the second wall is P (unit: ℃), and 1500≤D2*P≤3000.

14. The battery according to claim 1, wherein the impact resistance of the second wall is E, and E≥20 KJ / m2.

15. The battery according to claim 14, wherein E≥30 KJ / m2.

16. The battery according to claim 1, wherein the capacity of the battery cell is A (unit: ah); the distance between the first wall and the second wall is h (unit: mm); 0.01≤h / A≤0.

1. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 17. The battery of claim 8, wherein the exhaust device further has a third wall disposed on a surface of the second wall facing away from the first wall, the third wall being configured to support the second wall.

18. The battery of claim 17, wherein the third wall has a strength X, and X≥70 MPa.

19. The battery of claim 18, wherein X≥80 MPa.

20. The battery of claim 17, wherein the third wall has a thickness D3, and 0.3 mm≤D3≤4 mm.

21. The battery of claim 20, wherein 0.5 mm≤D3≤3 mm.

22. The battery of claim 17, wherein the third wall has a thickness D3 in mm and a strength X in MPa, and 100≤D3*X≤3000.

23. The battery of claim 22, wherein 300≤D3*X≤2500.

24. The battery of claim 17, wherein the second wall has a thickness D2, and the third wall has a thickness D3, and 1 mm≤D2+D3≤10 mm.

25. The battery of claim 24, wherein, 2 mm≤D2+D3≤7 mm.

26. The battery of claim 1, wherein a plurality of the battery cells are stacked together; the exhaust device has a plurality of the gas inlets, and the plurality of the gas inlets are spaced apart along a stacking direction of the battery cells to correspond to the first pressure relief mechanisms of the battery cells one by one.

27. The battery of any one of claims 1-26, wherein the exhaust device has an exhaust outlet in communication with the exhaust passage, and the exhaust outlet is in communication with an outside of the case.

28. The battery of any one of claims 1-26, wherein the wall of the case is provided with a second pressure relief mechanism, and the exhaust device has an exhaust outlet in communication with the exhaust passage, and the exhaust outlet is disposed inside the case and toward the second pressure relief mechanism.

29. An electrical device, comprising: a battery of any one of claims 1-28, wherein the battery is configured to provide electrical energy.

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