Battery apparatus and electric device

Abstract

The present disclosure applies to the technical field of batteries. Provided are a battery apparatus and an electric device. The battery apparatus comprises a plurality of battery cells and a busbar component. Each battery cell comprises a pressure relief valve, a terminal post and a battery end cover, wherein the pressure relief valve and the terminal post are arranged on the battery end cover; and the busbar component is electrically connected to the terminal posts of any two battery cells among the plurality of battery cells, and is insulated from the battery end covers. The busbar component is electrically connected to the terminal posts of any two battery cells among the plurality of battery cells, wherein the voltage difference between at least one battery end cover and the busbar component having an overlapping orthographic projection with said battery end cover is greater than the voltage of one battery cell, and the shortest distance between the orthographic projection of the pressure relief valves and the projection of the busbar component is D, where D satisfies D≥4 mm. In this way, when thermal runaway occurs in a battery cell and causes the pressure relief valve to eject high-temperature and high-speed airflow and particulate matter, the likelihood of a short circuit in the busbar component due to insulation failure between the busbar component and the battery end cover can be reduced.

Description

Battery device and electric appliance

[0001] Cross-reference to related applications

[0002] The present disclosure is based on and claims priority to Chinese Patent Application No. 202410845785.6, filed on June 27, 2024, entitled "Battery device and electric appliance", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of batteries, and in particular to a battery device and an electric appliance. BACKGROUND

[0004] A battery is usually composed of a plurality of battery cells. During use, there is a possibility of thermal runaway occurring in the battery cells. To ensure that the pressure inside the battery cells is released, a pressure relief valve needs to be provided to release the internal pressure when thermal runaway occurs.

[0005] In related technologies, the pressure relief valve of a single battery cell in a battery can easily cause heat diffusion during pressure relief, leading to arc drawing or short circuit phenomena in the entire battery, and further triggering more serious thermal runaway behavior. SUMMARY

[0006] To solve the above technical problems, the present disclosure provides a battery device and an electric appliance to reduce the possibility of thermal runaway of a single battery cell spreading to the entire battery device during pressure relief of the pressure relief valve.

[0007] In a first aspect, an embodiment of the present disclosure provides a battery device, comprising:

[0008] a plurality of battery cells, the battery cells comprising a pressure relief valve, a pole and a battery end cover, the pressure relief valve and the pole being arranged on the battery end cover;

[0009] a current collection component, the current collection component being electrically connected to the poles of any two battery cells of the plurality of battery cells and being insulated from the battery end cover;

[0010] wherein the voltage difference of the current collection component that coincides with the orthographic projection of at least one battery end cover is greater than the voltage of one battery cell, and the shortest distance between the orthographic projection of the pressure relief valve and the orthographic projection of the current collection component is D, D satisfies: D≥4mm, wherein the projection in the direction perpendicular to the plane where the battery end cover is located and toward the plane where the battery end cover is located is defined as the orthographic projection.

[0011] In the technical scheme, the voltage difference of the at least one busbar part whose battery end cover is coincident with the orthographic projection is greater than the voltage of one battery monomer, and the shortest distance D is greater than or equal to 4 mm, so that the possibility of short circuit of the busbar part caused by the destruction of the insulation protection between the busbar part and the battery end cover when the high-temperature high-speed airflow and particles are sprayed by the pressure relief valve due to the thermal runaway of the battery monomer is reduced, the possibility of the thermal runaway of a single battery monomer spreading to the whole battery device is reduced, and the use safety of the battery device is improved.

[0012] In some embodiments, D satisfies: D≥8 mm.

[0013] In the technical scheme, the shortest distance D is greater than or equal to 8 mm, so that the distance between the high-temperature high-speed airflow and particles sprayed by the pressure relief valve during the pressure relief process and the busbar part is increased, the possibility of short circuit of the busbar part caused by the destruction of the insulation protection between the busbar part and the battery end cover is further reduced, and the ability of the battery device to prevent thermal runaway is improved.

[0014] In some embodiments, the energy density of the battery monomer is E, and E satisfies: 500 Wh / L≤E≤1000 Wh / L.

[0015] In the technical scheme, the energy density of the battery monomer is limited, the intensity of the high-temperature high-speed airflow and particles sprayed by the pressure relief valve during the pressure relief process is reduced, and the possibility of short circuit of the busbar part caused by the destruction of the insulation protection between the busbar part and the battery end cover is reduced.

[0016] In some embodiments, D and E satisfy: D / E≥0.005 mm / (Wh / L).

[0017] In the technical scheme, the relationship between the intensity of the thermal runaway of the battery monomer and the shortest distance D is controlled, the possibility of short circuit of the busbar part caused by the destruction of the insulation protection between the busbar part and the battery end cover due to the high-temperature high-speed airflow and particles sprayed by the pressure relief valve is further reduced, and the possibility of the thermal runaway of a single battery monomer spreading to the whole battery device is reduced.

[0018] In some embodiments, D and E satisfy: D / E≥0.008 mm / (Wh / L).

[0019] In the technical scheme, the ratio between the shortest distance D and the energy density E of the battery monomer is increased, the ability of the battery device to prevent the thermal runaway of a single battery monomer from spreading to the whole battery device is further improved, and the use safety of the battery device is improved.

[0020] In some embodiments, the maximum voltage difference between the battery end cover and the busbar component coinciding with the orthographic projection satisfies U, and U satisfies 4V≤U≤80V.

[0021] In the above technical solution, the value of the maximum voltage difference U is limited, which can reduce the possibility of arc or short circuit between the battery end cover and the busbar component during pressure relief, thereby reducing the possibility of short circuit of the busbar component caused by damage of the insulation protection between the busbar component and the battery end cover, and improving the safety of the battery device.

[0022] In some embodiments, D and U satisfy D / U≥0.08mm / V.

[0023] In the above technical solution, the relationship between the maximum voltage difference U and the shortest distance D is controlled to reduce the possibility of arc or short circuit between the busbar component and the battery end cover induced by the hot flow ejected by the pressure relief valve, thereby improving the safety of the battery device.

[0024] In some embodiments, D and U satisfy D / U≥0.12mm / V.

[0025] In the above technical solution, the ratio of the maximum voltage difference U and the shortest distance D is increased, which further increases the ability to prevent arc or short circuit between the busbar component and the battery end cover, thereby improving the safety of the battery device.

[0026] In some embodiments, the battery device comprises a first insulation component, and the first insulation component is arranged between the busbar component and the battery end cover.

[0027] In the above technical solution, the insulation protection between the busbar component and the battery end cover can be improved.

[0028] In some embodiments, the battery device further comprises a second insulation component, and the second insulation component is arranged on the surface of the busbar component away from the battery end cover.

[0029] In the above technical solution, during the pressure relief process of the pressure relief valve, the influence of the high-temperature high-speed airflow and particulate matter ejected by the pressure relief valve on the busbar component can be reduced, thereby improving the safety of the battery device.

[0030] In some embodiments, D satisfies D≤50mm.

[0031] In the above technical solution, when the shortest distance D is too large, the possibility of excessive resistance of the busbar component caused by too small width of the busbar component can be reduced, thereby reducing the heat generated by the busbar component during the charging and discharging process of the battery device.

[0032] In a second aspect, the embodiments of the present disclosure provide a power consuming device, comprising the battery device of any of the embodiments of the present disclosure, and the battery device is configured to provide electric energy.

[0033] In the above technical solution, by using the battery device described above, the possibility of short circuit of the current collecting component caused by the destruction of the insulation protection between the current collecting component and the battery end cover when the pressure relief valve sprays high-temperature high-speed airflow and particulate matter due to thermal runaway of the battery monomer is reduced, the possibility of thermal runaway of a single battery monomer spreading to the entire battery device is reduced, and the use safety of the battery device is improved, so that the power consuming device has high reliability.

[0034] The above description is only a summary of the technical solutions of the present disclosure. In order to make the technical means of the present disclosure more clearly understood, the embodiments of the present disclosure can be implemented in accordance with the content of the description, and in order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific embodiments of the present disclosure are described below. BRIEF DESCRIPTION OF DRAWINGS

[0035] Fig. 1 is a structural schematic diagram of a power consuming device provided by the embodiments of the present disclosure;

[0036] Fig. 2 is a structural schematic diagram of a battery device provided by the embodiments of the present disclosure;

[0037] Fig. 3 is a structural schematic diagram of a battery monomer in Fig. 2.

[0038] BRIEF DESCRIPTION OF DRAWINGS 10, battery device; 1, battery monomer; 11, pressure relief valve; 12, pole; 13, battery end cover; 14, shell; 2, current collecting component; D, shortest distance; 3, vehicle; 31, controller; 32, motor. DETAILED DESCRIPTION

[0039] In order to make the purposes, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present disclosure and do not limit the present disclosure.

[0040] In the specific embodiments, various specific technical features described in the embodiments can be combined in any suitable manner without contradiction, for example, different embodiments and technical solutions can be formed by combining different specific technical features. In order to avoid unnecessary repetition, various possible combinations of each specific technical feature in the present disclosure are not described again.

[0041] In the following description, the terms "first," "second," etc., are used merely to distinguish different objects and do not indicate that the objects have the sameness or relationship. It should be understood that the directional descriptions "above," "below," "outside," and "inside" refer to the orientation under normal use conditions, while "left" and "right" refer to the left and right directions shown in the corresponding diagrams, which may or may not be the left and right directions under normal use conditions.

[0042] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. "At least two" means two or more.

[0043] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of the application areas of battery devices, the market demand is constantly increasing, and their production is also continuously growing.

[0044] During the production of individual battery cells, a pressure relief valve is required on the battery end cap to release internal pressure in the event of thermal runaway. However, in related technologies, the pressure relief valve can easily cause a short circuit in the busbar components during the pressure relief process, leading to thermal diffusion between battery cells.

[0045] The applicant's research found that in the relevant technology, the voltage difference between at least one battery end cap and the busbar component whose orthographic projection coincides with the voltage of a single battery cell is greater than the voltage of a single battery cell. In other words, the voltage difference between at least one battery end cap and the busbar component located above it is greater than the voltage of a single battery cell. In such a battery cell, after thermal runaway, the pressure relief valve will release the internal pressure of the battery cell and spray high-temperature fumes and / or electrolyte outward. The high-temperature fumes and / or electrolyte will damage the insulation protection of the busbar component, causing insulation failure of the busbar component. This will cause arcing or short circuit between the busbar component and the battery end caps of other battery cells, resulting in thermal runaway of other battery cells and thermal diffusion inside the battery cell, affecting the safety of the battery cell.

[0046] Based on the above considerations, in order to reduce the possibility of heat diffusion caused by the pressure relief valve during the pressure relief process, the applicant has designed a battery device including a plurality of battery monomers and a busbar component after in-depth research.

[0047] The battery monomer includes a pressure relief valve, a pole and a battery end cover, and the pressure relief valve and the pole are arranged on the battery end cover. The busbar component is electrically connected to the poles of any two battery monomers of the plurality of battery monomers and is insulated from the battery end cover. Among them, the voltage difference of at least one battery end cover and the busbar component coinciding with the orthographic projection is greater than the voltage of one battery monomer, and the shortest distance between the orthographic projection of the pressure relief valve and the projection of the busbar component is D (hereinafter referred to as the shortest distance D), D satisfies: D≥4mm, wherein the orthographic projection is defined as the projection in the direction perpendicular to the plane where the battery end cover is located, towards the plane where the battery end cover is located. In this way, by limiting the minimum value of the shortest distance D, the possibility of short circuit of the busbar component caused by the destruction of the insulation protection between the busbar component and the battery end cover when the battery monomer is in thermal runaway and the pressure relief valve sprays high-temperature high-speed airflow and particulate matter can be reduced. The possibility of thermal runaway of a single battery monomer spreading to the entire battery device can be reduced, thereby improving the safety of the battery device.

[0048] The battery monomer involved in the embodiments of the present disclosure refers to the smallest unit for storing and outputting electric energy. Among them, the battery monomer can be a secondary battery or a primary battery.

[0049] The embodiments of the present disclosure also provide a power consumption device including the above-mentioned battery device. The power consumption device is, for example, a mobile phone, a portable device, a notebook computer, an electric vehicle, an electric toy, an electric tool, an electric vehicle, a ship and a spacecraft, etc. For example, the spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The battery device is used to provide electric energy for the above-mentioned power consumption device.

[0050] It should be understood that the technical solutions described in the embodiments of the present disclosure are not only limited to the above-mentioned battery device and power consumption device, but can also be applied to all battery devices including a battery box and power consumption devices using the battery device. However, for the sake of brevity of description, the following embodiments will be described taking an electric vehicle as an example.

[0051] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of a vehicle 3 provided by some embodiments of the present disclosure. The vehicle 3 can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric vehicle, a hybrid vehicle, or a range extended vehicle, etc. The vehicle 3 is internally provided with a battery device 10, which can be arranged at the bottom, the head, or the tail of the vehicle 3. The battery device 10 can be used for power supply of the vehicle 3, for example, the battery device 10 can be used as an operating power source of the vehicle 3. The vehicle 3 can further include a controller 31 and a motor 32, and the controller 31 is used to control the battery device 10 to supply power to the motor 32, for example, to meet the working power demand of the vehicle 3 during starting, navigation, and driving.

[0052] In some embodiments of the present disclosure, the battery device 10 can not only be used as an operating power source of the vehicle 3, but also be used as a driving power source of the vehicle 3, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 3.

[0053] FIG. 2 is a structural schematic diagram of the battery device 10 provided by an embodiment of the present disclosure, and FIG. 3 is a structural schematic diagram of a battery cell 1 provided by an embodiment of the present disclosure. Referring to FIG. 2 and FIG. 3, the battery device 10 includes a plurality of battery cells 1 and a busbar component 2. The battery cell 1 includes a pressure relief valve 11, a pole 12, and a battery end cover 13, and the pressure relief valve 11 and the pole 12 are arranged on the battery end cover 13. The busbar component 2 is located on one side of the battery end cover 13 and is insulated from the battery end cover 13, and the busbar component 2 is used to electrically connect the poles 12 of any two battery cells 1 of the plurality of battery cells 1. Among them, the voltage difference of the busbar component 2 whose at least one battery end cover 13 and the normal projection coincide is greater than the voltage of one battery cell 1. The shortest distance between the normal projection of the pressure relief valve 11 and the normal projection of the busbar component 2 is defined as D, and D≥4mm. Among them, the normal projection is defined as the projection in the direction perpendicular to the plane where the battery end cover 13 is located, towards the plane where the battery end cover 13 is located.

[0054] The battery cell 1 can further include a shell 14 and an electrode assembly (not shown in the figure), and the shell 14 is a hollow structure with one side open, and the electrode assembly is arranged in the shell 14. The electrode assembly is a component that undergoes an electrochemical reaction in the battery cell 1. The electrode assembly is mainly formed by winding or layering a positive plate and a negative plate, and a diaphragm is usually arranged between the positive plate and the negative plate. The shape of the shell 14 can be determined according to the specific shape and size of the electrode assembly. The material of the shell 14 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present disclosure do not make special limitations thereon.

[0055] The battery end cover 13 refers to a component that is covered on the opening of the shell 14 to isolate the internal environment of the battery monomer 1 from the external environment. The battery end cover 13 can be made of a material with certain hardness and strength, so that on the one hand, it can provide stable support for the pole 12, the pressure relief valve 11 and the busbar component 2; on the other hand, it can make the battery monomer 1 have higher structural strength, and the safety performance can also be improved. The material of the battery end cover 13 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the present disclosure does not make special restrictions thereon.

[0056] The pole 12 is used to be electrically connected with the electrode assembly to serve as a component for conveying and conducting current in the battery monomer 1. The specific manner in which the pole 12 is arranged on the battery end cover 13 is not limited and can be riveting, welding or threaded connection.

[0057] The pressure relief valve 11 serves as a device for adjusting the pressure balance inside and outside the battery monomer 1. When the pressure inside the battery monomer 1 exceeds a set threshold, the pressure relief valve 11 opens to release the pressure inside the battery monomer 1 to achieve the function of adjusting the pressure balance inside and outside the battery monomer 1.

[0058] A plurality of battery monomers 1 can be arranged in sequence along a certain direction, and the busbar component 2 is used to be electrically connected with the poles 12 of any two battery monomers 1. The battery device 10 can further include two end plates arranged at both ends of the arrangement direction of the plurality of battery monomers 1 and connected with each other to fix the plurality of battery monomers 1. The two end plates can be connected with each other by a binding belt or through a side plate.

[0059] Taking a square battery monomer 1 as an example, a plurality of battery monomers 1 can be arranged in sequence along the thickness direction thereof. The busbar component 2 is generally in a flat plate structure, and the two ends of the busbar component 2 can be respectively connected with the poles 12 of the two adjacent battery monomers 1. The two ends of the busbar component 2 can also be respectively connected with the poles 12 of the two battery monomers 1 spaced apart from each other, and the middle region of the busbar component 2 is insulatively arranged above the battery end cover 13 of one or more battery monomers 1.

[0060] The normal projection of the busbar component 2 above the battery end cover 13 at least partially falls on the battery end cover 13, and the voltage difference of the busbar component 2 above at least one battery end cover 13 is greater than the voltage of one battery monomer 1. The voltage difference of the busbar component 2 above at least one battery end cover 12 can be greater than the voltage of one battery monomer 1. The voltage of the battery monomer 1 can be the nominal voltage of the battery monomer 1, which is different for different types. For example, the nominal voltage of a ternary lithium battery monomer can be 3.6V, and the nominal voltage of a lithium iron phosphate battery monomer can be 3.2V.

[0061] The busbar component 2 can include a plurality of busbar components 2, each of which is electrically connected to the pole 12 of two battery monomers 1 of the plurality of battery monomers 1 to connect the plurality of battery monomers 1 in series, in parallel, or in a mixed connection, where the mixed connection refers to a connection in which both series and parallel connections are present in the plurality of battery monomers 1.

[0062] It can be understood that, when the voltage difference of the busbar component 2 coinciding with the normal projection of at least one battery end cover 13 of the battery device 10 is greater than the nominal voltage of one battery monomer 1, by limiting the shortest distance D to be greater than or equal to 4 mm, a safe distance can be maintained between the high-temperature substance sprayed by the pressure relief valve 11 and the busbar component 2, and the possibility of short circuit of the busbar component 2 caused by the insulation protection between the busbar component 2 and the battery end cover 13 being destroyed when the battery monomer 1 is in thermal runaway and the pressure relief valve 11 sprays high-temperature high-speed airflow and particulate matter can be reduced, thereby reducing the possibility of the thermal runaway of a single battery monomer 1 spreading to the entire battery device 10, and further improving the use safety of the battery device 10.

[0063] It should be noted that the shortest distance refers to the minimum value of the distance between the normal projection of the pressure relief valve 11 and the normal projection of the busbar component 2 in any direction of the plane where the battery end cover 13 is located. When the busbar component 2 includes a plurality of busbar components 2, the shortest distance D greater than or equal to 4 mm can refer to the distance between the normal projection of the pressure relief valve 11 and the normal projection of any one of the busbar components 2 in any direction of the plane where the battery end cover 13 is located. In this way, the possibility of short circuit of the busbar component 2 caused by the insulation protection between the busbar component 2 and the battery end cover 13 being destroyed when the battery monomer 1 is in thermal runaway and the pressure relief valve 11 sprays high-temperature high-speed airflow and particulate matter can be reduced.

[0064] In some embodiments, the shortest distance D satisfies: 4 mm≤D≤50 mm. For example, the shortest distance D can be 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 30 mm, 40 mm, or 50 mm, and the like.

[0065] For the case where the voltage difference of the busbar component 2 coinciding with the normal projection of at least one battery end cover 13 of the battery device 10 is greater than the nominal voltage of one battery monomer 1, by controlling the shortest distance D within the above range, a safe distance can be maintained between the high-temperature substance sprayed by the pressure relief valve 11 and the busbar component 2, and the possibility of the thermal runaway of a single battery monomer 1 spreading to the entire battery device 10 can be reduced. At the same time, the busbar component 2 has a certain width, which can reduce the resistance of the busbar component 2, and further reduce the heat generated by the busbar component 2 during the charging and discharging process of the battery device 10. The width direction of the busbar component 2 is perpendicular to the current transmission direction of the busbar component 2.

[0066] In some embodiments, the battery device 10 can further include a battery box (not shown in the figures) in which the plurality of battery cells 1 are accommodated. The battery box can be configured in various ways to provide a space for accommodating the battery cells 1. In some embodiments, the battery box can include a first part and a second part, the first part and the second part being coupled to each other to define a space for accommodating the battery cells 1. The second part can be a hollow structure with one open side, and the first part can be a plate-shaped structure that is coupled to the open side of the second part to define the space together with the second part. Alternatively, the first part and the second part can both be hollow structures with one open side, and the open side of the first part is coupled to the open side of the second part. Of course, the battery box formed by the first part and the second part can have various shapes, such as a cylinder, a cuboid, etc.

[0067] In some embodiments, as shown in FIGS. 2 and 3, the shortest distance D satisfies D≥8mm, i.e., the shortest distance D is not less than 8mm. It can be understood that, while ensuring that the pressure relief valve 11 has the pressure relief function, increasing the shortest distance D can increase the distance between the high-temperature and high-speed airflow and the particulate matter ejected by the pressure relief valve 11 during pressure relief and the current collecting member 2, further reduce the possibility of the insulation protection between the current collecting member 2 and the battery end cover 13 being damaged to cause short circuit of the current collecting member 2, and improve the ability of the battery device 10 to prevent thermal diffusion.

[0068] In some embodiments, the shortest distance D satisfies 8mm≤D≤40mm. For example, the shortest distance D can be 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 30mm, or 40mm. By controlling the shortest distance D within the above range, the possibility of thermal runaway of a single battery cell 1 spreading to the entire battery device 10 can be further reduced, and at the same time, the width of the current collecting member 2 can be further increased, thereby further reducing the resistance of the current collecting member 2.

[0069] In some embodiments, the energy density of the battery cell 1 is E, and the energy density E satisfies 500Wh / L≤E≤1000Wh / L, where Wh / L (Watt-hour per liter) is the unit of energy density, W represents watt, h represents hour, and L represents liter. The energy density = (discharge rate x 3.7) / (thickness x width x length). The unit of the discharge rate is milliampere-hour, and the thickness, width, and length refer to the dimensions of the outer shell formed by the outer shell 14 and the battery end cover 13 of the battery cell 1, and the units are centimeters.

[0070] For example, the energy density of the battery monomer 1 can be 600 Wh / L, 700 Wh / L, 800 Wh / L, 900 Wh / L, 1000 Wh / L.

[0071] It can be understood that reasonably limiting the energy density E of the battery monomer 1 can reduce the pressure that needs to be released inside the battery monomer 1 after the battery monomer 1 appears thermal runaway, can reduce the intensity of the thermal runaway of the battery monomer 1, that is, reduce the intensity of the high-temperature high-speed airflow and particles sprayed by the pressure relief valve 11 in the pressure relief process, thereby reducing the possibility that the insulation protection between the busbar component 2 and the battery end cover 13 is damaged to cause the short circuit of the busbar component 2.

[0072] In some embodiments, referring to FIGS. 2 and 3, D and E satisfy: D / E≥0.005 mm / (Wh / L), that is, the ratio of the shortest distance D to the energy density E of the battery monomer 1 is not less than 0.005 mm / (Wh / L), for example, the shortest distance D is 5 mm, the energy density E of the battery monomer 1 is 1000 Wh / L, and the ratio of the shortest distance D to the energy density E of the battery monomer 1 is 0.005 mm / (Wh / L).

[0073] It can be understood that controlling the relationship between the intensity of the thermal runaway of the battery monomer 1 and the shortest distance D can, on the one hand, reasonably determine the size of the shortest distance D according to the energy density E of the battery monomer 1, reasonably utilize the space above the battery end cover 13, and facilitate production and manufacturing; on the other hand, can improve the accuracy of the minimum value of the shortest distance D to reduce the possibility that the high-temperature high-speed airflow and particles sprayed by the pressure relief valve 11 cause the insulation protection between the busbar component 2 and the battery end cover 13 to be damaged to cause the short circuit of the busbar component 2, thereby reducing the possibility that the thermal runaway of a single battery monomer 1 spreads to the entire battery device 10.

[0074] In some embodiments, referring to FIGS. 2 and 3, D and E satisfy: D / E≥0.008 mm / (Wh / L), that is, the ratio of the shortest distance D to the energy density E of the battery monomer 1 is not less than 0.008 mm / (Wh / L), for example, the shortest distance D is 8 mm, the energy density E of the battery monomer 1 is 1000 Wh / L, and the ratio of the shortest distance D to the energy density of the battery monomer 1 is 0.008 mm / (Wh / L).

[0075] In this way, the minimum shortest distance D corresponding to the energy density of the battery monomer 1 can be improved, the safety distance between the high-temperature high-speed airflow and particles sprayed by the pressure relief valve 11 and the busbar component 2 can be increased, so that the shortest distance D has a safety redundancy while meeting the requirements, thereby improving the ability of the battery device 10 to prevent the thermal runaway of a single battery monomer 1 from spreading to the entire battery device 10, and improving the use safety of the battery device 10.

[0076] In some related technologies, the busbar component is a component for electrically connecting multiple battery monomers, the battery monomers are connected in series, parallel or mixed connection through the busbar component, multiple busbar components can be arranged on the top side of each battery monomer, the voltage values of different busbar components on the top side of each battery monomer are not the same, when the maximum voltage difference between the single battery end cover and the busbar component on the top side thereof is too large, the battery end cover is prone to arc phenomenon with the busbar component, resulting in short circuit of the busbar component.

[0077] In some embodiments, the maximum voltage difference U between the battery end cover 13 and the busbar component 2 coinciding with the orthographic projection satisfies: 4V≤U≤80V, that is, the maximum voltage difference U between the battery end cover 13 and the busbar component 2 on the top side thereof is 4V-80V (voltage unit, volt, V for short), for example, the maximum voltage difference U can be 4V, 6V, 10V, 20V, 30V, 40V, 50V, 60V, 70V, 80V. For example, the voltage value of any one battery end cover 13 is V0, and there are two busbar components 2 on the top side of the battery end cover 13, one of which has a voltage value of V1, and the other has a voltage value of V2. If V1-V0>V2-V0, then the maximum voltage difference U between the battery end cover 13 and the busbar component 2 coinciding with the orthographic projection is V1-V0.

[0078] It can be understood that by limiting the value of the maximum voltage difference U, the possibility of arc or short circuit between the battery end cover 13 and the busbar component 2 during pressure relief can be reduced, thereby reducing the possibility of short circuit of the busbar component 2 causing thermal runaway of multiple battery monomers 1, and improving the safety of the battery device 10.

[0079] In some embodiments, referring to FIGS. 2 and 3, D and U satisfy: D / U≥0.08mm / V, that is, the ratio of the shortest distance D to the maximum voltage difference U is not less than 0.08mm / V, for example, the shortest distance D is 8mm, the maximum voltage difference U is 80V, and the ratio of the shortest distance D to the maximum voltage difference U is 0.10mm / V.

[0080] It can be understood that by controlling the relationship between the maximum voltage difference U and the shortest distance D, on the one hand, the size of the shortest distance D can be reasonably determined according to the maximum voltage difference U of the battery monomer 1, the space above the battery end cover 13 is reasonably utilized, and production and manufacturing are facilitated; on the other hand, the shortest distance D can be further limited to increase the distance between the high-temperature high-speed airflow and particulate matter formed by the pressure relief valve 11 and the busbar component 2, so as to reduce the possibility of arc or short circuit between the busbar component 2 and the battery end cover 13 induced by the high-temperature high-speed airflow and particulate matter ejected by the pressure relief valve 11, and improve the safety of the battery device 10.

[0081] In some embodiments, referring to FIGS. 2 and 3, D and U satisfy: D / U≥0.12 mm / V, i.e., the ratio of the shortest distance D to the maximum voltage difference U is not less than 0.12 mm / V. For example, the shortest distance D is 10 mm, the maximum voltage difference U is 80 V, and the ratio of the shortest distance D to the maximum voltage difference U is 0.125 mm / V. It can be understood that increasing the ratio of the maximum voltage difference U to the shortest distance D can increase the minimum shortest distance D corresponding to the maximum voltage difference U of the battery monomer 1, increase the ability to prevent the occurrence of arc or short circuit between the busbar component 2 and the battery end cover 13, and thus improve the safety of the battery device 10.

[0082] In some embodiments, the battery device 10 includes a first insulating component (not shown in the figure) arranged between the busbar component 2 and the battery end cover 13. It can be understood that on the one hand, the first insulating component can increase the distance between the busbar component 2 and the battery end cover 13, and on the other hand, the first insulating component can effectively isolate the flow of current between the busbar component 2 and the battery end cover 13, and can improve the insulation protection between the busbar component 2 and the battery end cover 13.

[0083] In some embodiments, the battery device 10 further includes a second insulating component (not shown in the figure) arranged on the surface of the busbar component 2 away from the battery end cover 13. It can be understood that the second insulating component covers the surface of the busbar component 2, and can reduce the influence of the high-temperature and high-speed airflow and particles sprayed by the pressure relief valve 11 on the busbar component 2 during the pressure relief process of the pressure relief valve 11, and improve the safety of the battery device 10.

[0084] It should be noted that the specific material of the first insulating component and the second insulating component is not limited, for example, can be at least one of the following: epoxy resin film, mica paper, electrophoretic film, asbestos layer, ceramic layer, silicon oxide film, silicon nitride film, aluminum oxide film, aluminum nitride film, polyimide film, polyethylene film, polyvinylidene fluoride film, and polytetrafluoroethylene film.

[0085] In actual application, the thickness of the first insulating component and the second insulating component can be set according to actual conditions, for example, the thickness of the first insulating component can be 0.5-3 mm, the thickness of the second insulating component can be 0.5-3 mm, etc. The specific thickness of the first insulating component and the second insulating component is not specially limited in the embodiments of the present disclosure.

[0086] In practical applications, the first insulating component needs to be clamped between the busbar component 2 and the battery end cover 13, and the second insulating component needs to cover the surface of the busbar component 2. Therefore, the specific shape of the first insulating component and the second insulating component is determined according to the shape of the busbar component 2, and the shape of the first insulating component and the second insulating component can be the same as the shape of the busbar component 2. The specific shape of the first insulating component and the second insulating component is not specially limited in the embodiments of the present disclosure.

[0087] In some specific embodiments, the shortest distance D is not less than 4 mm, the ratio of the shortest distance D to the energy density E of the battery monomer 1 is not less than 0.005 mm / (Wh / L), and the ratio of the shortest distance D to the maximum voltage difference U is not less than 0.08 mm / V. In this way, the minimum value of the shortest distance D is jointly limited by the maximum voltage difference U and the energy density E, which can not only reduce the influence of the high intensity of the thermal runaway of the battery monomer 1 on the busbar component 2, but also reduce the possibility of the arc phenomenon between the busbar component 2 and the battery end cover 13.

[0088] In some specific embodiments, the shortest distance D is not less than 8 mm, the ratio of the shortest distance D to the energy density E of the battery monomer 1 is not less than 0.008 mm / (Wh / L), and the ratio of the shortest distance D to the maximum voltage difference U is not less than 0.12 mm / V. In this way, the influence of the pressure relief operation of the pressure relief valve 11 on the busbar component 2 can be reduced, and the safety reserve of the device 10 can be improved, and the thermal runaway of a single battery monomer 1 is limited to spread to other battery monomers 1 in the battery. The following will briefly introduce two comparative examples and eight embodiments of the present disclosure in combination with Table 1. Table 1 is the test data of the two comparative examples and the eight embodiments of the present disclosure:

[0089] In Table 1, D represents the shortest distance, U represents the maximum voltage difference, E represents the energy density of the battery monomer 1, D / U represents the ratio of the shortest distance D to the maximum voltage difference U, and D / E represents the ratio of the shortest distance D to the energy density of the battery monomer 1.

[0090] As can be seen from Table 1, the test results of Examples 1 to 8 are normal, that is, there is no phenomenon of the thermal runaway of a single battery monomer 1 spreading to the entire battery device 10. In Comparative Example 1 and Comparative Example 2, because the shortest distance D does not meet the requirement of D≥4 mm, the thermal runaway of a single battery monomer 1 destroys the insulation protection between the busbar component 2 and the battery end cover 13, resulting in a short circuit of the busbar component 2, and the thermal runaway of a single battery monomer 1 spreads to the entire battery device 10.

[0091] In the description of the disclosure, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the disclosure. In the disclosure, the illustrative description of the above terms is not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or at least two embodiments or examples. In addition, those skilled in the art can combine different embodiments or examples described in the disclosure and the features of different embodiments or examples without contradiction.

[0092] The above is only the preferred embodiment of the disclosure, and is not intended to limit the disclosure. Those skilled in the art can make various modifications and changes to the disclosure. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the disclosure shall be included in the protection scope of the disclosure.

Claims

1. A battery device, comprising: Multiple battery cells, each battery cell including a pressure relief valve, a terminal post and a battery end cap, wherein the pressure relief valve and the terminal post are disposed on the battery end cap; A current-combining component is electrically connected to the terminals of any two of the battery cells and is insulated from the battery end cap; wherein, the voltage difference between at least one current-combining component whose orthographic projection coincides with that of the battery end cap is greater than the voltage of one of the battery cells, and the shortest distance between the orthographic projection of the pressure relief valve and the orthographic projection of the current-combining component is D, where D satisfies: D≥4mm, where the orthographic projection is defined as the projection along the plane perpendicular to the plane where the battery end cap is located.

2. The battery device according to claim 1, wherein, D satisfies: D≥8mm.

3. The battery device according to claim 1 or 2, wherein, The energy density of the battery cell is E, and E satisfies: 500Wh / L≤E≤1000Wh / L.

4. The battery device according to claim 3, wherein, D and E satisfy: D / E≥0.005mm / (Wh / L).

5. The battery device according to claim 4, wherein, D and E satisfy: D / E≥0.008mm / (Wh / L).

6. The battery device according to any one of claims 1 to 5, wherein, The maximum voltage difference between the battery end cap and the busbar component whose orthogonal projection coincides is U, and U satisfies: 4V≤U≤80V.

7. The battery device according to claim 6, wherein, D and U satisfy: D / U≥0.08mm / V.

8. The battery device according to claim 7, wherein, D and U satisfy: D / U≥0.12mm / V.

9. The battery device according to any one of claims 1 to 8, wherein, The battery device further includes a first insulating component, which is sandwiched between the busbar and the battery end cap.

10. The battery device according to claim 9, wherein, The thickness of the first insulating component is 0.5 to 3 mm.

11. The battery device according to claim 9 or 10, wherein, The first insulating component has the same shape as the busbar component.

12. The battery device according to any one of claims 9 to 11, wherein, The first insulating component is made of at least one of the following materials: epoxy resin film, mica paper, electrophoretic film, asbestos layer, ceramic layer, silicon oxide film, silicon nitride film, aluminum oxide film, aluminum nitride film, polyimide film, polyethylene film, polyvinylidene fluoride film, and polytetrafluoroethylene film.

13. The battery device according to any one of claims 1 to 8, wherein, The battery device further includes a second insulating component disposed on the surface of the busbar component away from the battery end cap.

14. The battery device according to claim 13, wherein, The thickness of the second insulating component is 0.5 to 3 mm.

15. The battery device according to claim 13 or 14, wherein, The second insulating component has the same shape as the busbar component.

16. The battery device according to any one of claims 13 to 15, wherein, The material of the second insulating component is at least one of epoxy resin film, mica paper, electrophoretic film, asbestos layer, ceramic layer, silicon oxide film, silicon nitride film, aluminum oxide film, aluminum nitride film, polyimide film, polyethylene film, polyvinylidene fluoride film, and polytetrafluoroethylene film.

17. The battery device according to any one of claims 1 to 8, wherein, D satisfies: D≤50mm.

18. The battery device according to any one of claims 1 to 8, wherein, D satisfies: D≤40mm.

19. The battery device according to any one of claims 1 to 8, wherein, The busbar component has a flat plate structure.

20. An electrical device comprising a battery device according to any one of claims 1 to 19, the battery device being used to provide electrical energy.

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