Battery and electric device

Abstract

The invention provides a battery and a power utilization device. The battery comprises a sealed box body, a heat exchange plate, a detection piece, a controller and at least one battery monomer, and the at least one battery monomer is arranged in the sealed box body; the heat exchange plate is arranged in the sealed box body and is arranged to be in contact with the surface of at least one battery monomer, a liquid heat exchange medium circulates in the heat exchange plate, and the detection piece is arranged in the heat exchange plate and is used for detecting the real-time conductivity of the liquid heat exchange medium; the controller is in communication connection with the detection part and used for obtaining the real-time conductivity and giving an alarm when the real-time conductivity exceeds a threshold value. According to the battery and the electric device provided by the invention, the conductivity of the liquid heat exchange medium can be automatically monitored so as to control the conductivity of the liquid heat exchange medium within a proper range, so that good battery heat management performance is provided, the risk of fire and explosion of the battery after leakage of the liquid heat exchange medium can be reduced, and the service life of the battery is prolonged. And the safety of the battery can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to batteries and electrical devices. Background Art

[0002] New energy batteries are being used more and more widely in life and industry. For example, new energy vehicles equipped with batteries have been widely used. In addition, batteries are also being increasingly used in energy storage fields.

[0003] In electric vehicles, the battery pack is the power source of the whole vehicle and has an important impact on the performance of the whole vehicle, such as the vehicle's passability, safety, reliability and durability. The existing battery pack controls and manages the heat of the battery pack by exchanging heat with the batteries in the battery pack through a liquid cooling plate through which coolant flows.

[0004] In addition, improving the safety of battery packs is a topic that the industry continues to research and develop. Since the coolant in the battery pack has the risk of leakage, once leaked, there is a risk of causing the battery pack to catch fire or explode. Therefore, how to reduce the safety risk of the battery system caused by accidental leakage of coolant while ensuring the thermal management performance of the battery in the battery pack is one of the topics that the industry needs to solve in order to improve the safety of battery packs. Summary of the invention

[0005] In order to solve the above-mentioned problems in the prior art, the embodiments of the present application provide a battery and an electrical device, so as to provide good battery thermal management performance, reduce the safety risks of fire or even explosion caused by coolant leakage, and improve the safety of the battery.

[0006] The technical solution of the embodiment of the present application is implemented as follows.

[0007] In a first aspect, the present application provides a battery, comprising: a sealed box; at least one battery cell disposed in the sealed box; a heat exchange plate disposed in the sealed box and configured to contact the surface of at least one of the battery cells, a liquid heat exchange medium flowing in the heat exchange plate, a detection element disposed in the heat exchange plate, and used to detect the real-time conductivity of the liquid heat exchange medium; a controller, communicatively connected to the detection element, and used to obtain the real-time conductivity and alarm when the real-time conductivity exceeds a threshold value.

[0008] In the technical solution of the embodiment of the present application, the detection element is used to detect the real-time conductivity of the liquid heat exchange medium, and the controller is used to obtain the real-time conductivity measured by the detection element and to alarm when the real-time conductivity exceeds the threshold value. Therefore, the controller can monitor the real-time conductivity of the liquid heat exchange medium and promptly prompt risks, thereby effectively reducing the risk of short circuit between the sealed box and the internal high-voltage components due to conduction of the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance, thereby improving the safety of the battery and even the electrical devices using the battery.

[0009] In some embodiments, when the total voltage of the battery in a fully charged state does not exceed 900 V, the threshold value does not exceed 500 μS / cm.

[0010] For batteries with a total voltage not exceeding 900V, the threshold value of the conductivity of the liquid heat exchange medium does not exceed 500μS / cm, which can effectively reduce the risk of short circuit between the sealed box and the internal high-voltage devices due to the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0011] In some embodiments, when the total voltage of the battery in a fully charged state does not exceed 1500 V, the threshold value does not exceed 100 μS / cm.

[0012] For batteries with a total voltage not exceeding 1500V, the threshold value of the conductivity of the liquid heat exchange medium does not exceed 100μS / cm, which can effectively reduce the risk of short circuit between the sealed box and the internal high-voltage devices caused by the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0013] In some embodiments, when the total voltage of the battery in a fully charged state is in the range of 900V to 1500V, the threshold value is in the range of 50 to 500 μS / cm.

[0014] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 500 μS / cm for batteries with a total voltage of 900V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium can be reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0015] In some embodiments, when the total voltage of the battery in a fully charged state is in the range of 1000V to 1500V, the threshold value is in the range of 50 to 250 μS / cm.

[0016] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 250 μS / cm for batteries with a total voltage of 1000V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium can be reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0017] In some embodiments, when the total voltage of the battery in a fully charged state is in the range of 1200V to 1500V, the threshold value is in the range of 50 to 200 μS / cm.

[0018] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 200 μS / cm for batteries with a total voltage of 1200V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium can be reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0019] In some embodiments, when the total voltage of the battery in a fully charged state is in the range of 900V to 1500V, the threshold value is in the range of 50 to 100 μS / cm.

[0020] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 100 μS / cm for batteries with a total voltage of 900V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium can be further reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0021] In some embodiments, the detection element includes a conductivity sensor, which is disposed in the flow path of the liquid heat exchange medium and is used to detect the real-time conductivity of the liquid heat exchange medium.

[0022] By setting up a conductivity sensor, it is possible to accurately determine whether the conductivity of the liquid heat exchange medium exceeds the threshold. If it exceeds the threshold, a prompt to replace the liquid heat exchange medium will be given in time, thereby effectively reducing the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium. This can effectively reduce the risk of battery fire and explosion while providing good battery thermal management performance, thereby improving the safety of the battery and even the electrical devices using the battery.

[0023] In some embodiments, an inner wall of at least the high-voltage region of the sealed box is provided with an insulating layer.

[0024] The insulating layer and the low-conductivity liquid heat exchange medium work together to further reduce the risk of short circuit between the sealed box and the internal high-voltage devices caused by the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0025] In some embodiments, when the liquid heat exchange medium is in contact with the insulating layer of the sealed box, the battery does not spontaneously combust until the power of the fully charged battery drops to a minimum power level, wherein the minimum power level includes a power level of 0.

[0026] Therefore, even if the liquid heat exchange medium leaks and accumulates in the sealed box, the risk of short circuit between the sealed box and the internal high-voltage components caused by the liquid heat exchange medium can be effectively reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0027] In some embodiments, the insulating layer is provided on the inner wall by pasting an insulating film on the inner wall, or by spraying an insulating coating on the inner wall, or by installing an insulating liner on the inner wall.

[0028] Optionally, the insulating layer can be provided on the inner wall by one of the above three methods.

[0029] In some embodiments, the insulating film includes at least one of a ceramic insulating composite tape, mica paper, and a polymer insulating film.

[0030] Ceramic insulation composite tape, mica paper and polymer insulation film all have high insulation performance, which improves the insulation performance of the insulation layer.

[0031] In some embodiments, the insulating liner includes an liner made of engineering plastic.

[0032] The insulating liner made of engineering plastics not only has high insulation performance, but also has strong mechanical properties.

[0033] In some embodiments, the insulating coating comprises an epoxy insulating material coating.

[0034] The insulating layer is formed by spraying epoxy resin, so that the insulating layer has higher electrical insulation performance and physical mechanical properties.

[0035] In some embodiments, the polymer insulating film includes an insulating film made of at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, polymer polypropylene, polyethylene and nylon.

[0036] The above materials all have high insulation performance and can be made into high-molecular insulation films with high insulation performance, thereby improving the insulation performance of the insulation layer.

[0037] In some embodiments, the engineering plastic includes at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, high molecular weight polypropylene, polyethylene and nylon.

[0038] The above materials all have high insulation performance and can form engineering plastics with high insulation performance, thereby improving the insulation performance of the insulation layer.

[0039] In some embodiments, the heat exchange plate is bonded to the surface of at least one of the battery cells by an adhesive, and the adhesive includes a thermally conductive glue.

[0040] The heat exchange plate is connected to the battery cell by bonding, which improves the stability of the contact between the two, thereby improving the adequacy of heat exchange. The adhesive includes a thermally conductive adhesive, which improves the adequacy of heat exchange between the heat exchange plate and the battery cell, thereby improving the cooling effect.

[0041] In some embodiments, the heat exchange plate is bonded to the inner wall surface of the sealed box by an adhesive.

[0042] The heat exchange plate is bonded to the inner wall surface of the sealed box body, and the two are fixedly connected, thereby achieving the fixation of the heat exchange plate.

[0043] In some embodiments, the heat exchange plate is a hollow and flat liquid cooling plate, and the liquid heat exchange medium flowing in the hollow inner cavity of the liquid cooling plate is a coolant.

[0044] The heat exchange plate is set as a liquid cooling plate with a hollow structure, which can hold coolant inside, and does not need to set up additional cooling pipes and other structures, which helps to improve the volume utilization of the battery. The heat exchange plate is set as a flat structure, which is convenient for bonding with the battery and making full use of the space in the battery box. The flat structure helps to increase the contact area between the heat exchange plate and the battery cell, and improve the cooling effect.

[0045] In some embodiments, the battery further includes a liquid inlet pipe and a liquid discharge pipe, and a plurality of the heat exchange plates are provided, and the plurality of heat exchange plates are connected in parallel between the liquid inlet pipe and the liquid discharge pipe.

[0046] The provision of the liquid inlet pipe and the liquid discharge pipe enables the introduction and export of liquid heat exchange media such as coolant in the heat exchange plate. The parallel connection method makes the temperature of liquid heat exchange media such as coolant in each heat exchange plate more balanced, which is beneficial to uniform thermal management of multiple battery cells.

[0047] In a second aspect, the present application provides an electrical device, which includes the battery described above for providing electrical energy.

[0048] The electrical device provided in the embodiment of the present application includes the above-mentioned battery. Therefore, the electrical device has all the beneficial effects of the above-mentioned battery. Therefore, the electrical device is not prone to the safety problem of battery spontaneous combustion or even explosion after the liquid heat exchange medium of the battery leaks.

[0049] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0051] Figure 1 A three-dimensional schematic diagram of a first structure of a battery provided in some embodiments of the present application;

[0052] Figure 2 for Figure 1 Schematic diagram of the battery during the test;

[0053] Figure 3 A perspective schematic diagram of a second structure of a battery provided in some embodiments of the present application;

[0054] Figure 4 A three-dimensional schematic diagram of a third structure of a battery provided in some embodiments of the present application;

[0055] Figure 5 A perspective schematic diagram of a fourth structure of a battery provided in some embodiments of the present application;

[0056] Figure 6 A perspective schematic diagram of a fifth structure of a battery provided in some embodiments of the present application;

[0057] Figure 7 A perspective schematic diagram of a sixth structure of a battery provided in some embodiments of the present application;

[0058] Figure 8 A schematic diagram of the structure of an electrical device provided in some embodiments of the present application.

[0059] Description of Reference Numerals

[0060] 1 heat exchange plate; 2 battery cell; 21 high-voltage device; 3 sealed box; 31 high-voltage area; 4 liquid inlet pipe; 5 liquid discharge pipe; 6 conductivity sensor; 7 controller; 100 battery; 200 control unit; 300 motor; 1000 vehicle. DETAILED DESCRIPTION

[0061] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0063] In the description of the embodiments of the present application, the technical terms "first", "second", "third", "fourth", "fifth", "sixth", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0064] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0065] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0066] In the description of the embodiments of the present application, the orientation or position relationship indicated by technical terms such as "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", and "circumferential" are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0067] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0068] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and may be direct contact or contact through an intermediate medium layer. It may be contact with essentially no interaction force between the two contacting parties, or it may be contact with interaction force between the two contacting parties.

[0069] Below, this application is described in detail.

[0070] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0071] During the use of the battery, the battery temperature will rise, which will have some adverse effects on the battery itself and the surrounding environment. For example, too high a temperature will accelerate the rate of chemical reactions inside the battery, causing the battery capacity to decay faster, and will damage the battery's chemical structure and performance, thereby shortening the battery life; when the battery temperature is too high, its charging and discharging capabilities will be limited, resulting in a decrease in battery performance; too high a temperature will cause the internal pressure to rise, and even cause dangerous situations such as thermal runaway and explosion, posing a serious safety threat to users and the surrounding environment. To this end, the battery temperature is controlled by setting a battery thermal management system to keep the battery temperature within an appropriate temperature range.

[0072] A common battery thermal management system has a liquid cooling plate with a hollow pipe inside. One end of the hollow pipe is connected to the coolant inlet, and the other end of the hollow pipe is connected to the coolant outlet. The coolant flows through the entire hollow pipe and performs heat exchange through the hollow pipe, etc., to achieve thermal management of the battery. For example, the battery can be heated to a target temperature through heat exchange when the battery is at a low temperature, or it can be cooled to a target temperature through heat exchange when the battery is at a high temperature.

[0073] At present, in order to improve the thermal management performance of batteries, the structural design and layout of hollow pipes and liquid cooling plates are usually considered to improve space utilization and thermal management efficiency. However, the cooling structure of the battery cannot guarantee that there will be no leakage of coolant inside the battery in complex application conditions within the design life. After the coolant leaks, it will penetrate into the inner walls of the high-voltage area inside the battery, making the originally qualified insulation gap and creepage distance invalid. Short-circuit discharge and arcing and ignition will occur between the inner walls of the high-voltage area, resulting in violent energy release processes, which will eventually cause spontaneous combustion and even explosion safety issues. Therefore, how to solve the safety problems caused by coolant leakage needs to be studied.

[0074] The inventors of this application have noticed that the coolant of existing battery thermal management systems generally uses the traditional fuel vehicle engine coolant, which has a relatively strong conductivity. Moreover, with the repeated recycling of the coolant, the impurities and other particulate matter in the coolant increase, further improving the conductivity of the coolant and enhancing its electrical conductivity. At the same time, there are a large number of high-voltage interfaces inside the battery. When the coolant leaks, it will penetrate between these interfaces. The highly conductive coolant will make the originally qualified insulation gap and creepage distance invalid. Short-circuit discharge and arcing and ignition will occur between the high-voltage interfaces. Violent energy release processes, such as, will eventually cause safety problems for the battery system.

[0075] In order to prevent leaking coolant from invalidating the originally qualified insulation gap and creepage distance, the inventor of the present application has found through a large number of experiments that the risk of spontaneous combustion and even explosion caused by coolant leakage can be reduced by automatically monitoring the coolant in real time and controlling the conductivity of the coolant at a low level. Specifically, the conductivity of the coolant is monitored in real time using a detection component and a controller, and an alarm is sounded when the real-time conductivity exceeds a threshold. Therefore, it is possible to promptly prompt the replacement of a liquid heat exchange medium with a suitable conductivity, maintain a qualified insulation gap and creepage distance, and effectively reduce the risk of violent energy release such as short-circuit discharge and arcing ignition between high-voltage interfaces due to the conductivity of the coolant, thereby improving the safety performance of the battery.

[0076] Based on the above considerations, in order to provide good battery thermal management performance, reduce the safety risks of fire or even explosion caused by coolant leakage, and improve the safety of the battery, the inventor designed a battery after experiments and in-depth research.

[0077] The battery includes a sealed box, a detection component, a controller, at least one battery cell arranged in the sealed box, and a heat exchange plate arranged in the sealed box. The heat exchange plate is arranged to contact the surface of at least one battery cell. Liquid heat exchange medium flows in the heat exchange plate. The detection component is arranged in the heat exchange plate and is used to detect the real-time conductivity of the liquid heat exchange medium. The controller is communicatively connected with the detection component to obtain the real-time conductivity and alarm when the real-time conductivity exceeds a threshold value.

[0078] In this way, the controller can monitor the real-time conductivity of the liquid heat exchange medium and promptly prompt the replacement of the liquid heat exchange medium to control the conductivity of the coolant at a low level. By controlling the conductivity of the coolant at a low level, the leakage of coolant can be suppressed to prevent the originally qualified insulation gap and creepage distance from failing, thereby reducing the risk of fire or even explosion caused by violent energy release such as short-circuit discharge and arcing between the inner walls of the high-voltage area.

[0079] The battery provided in the embodiments of the present application may be a battery module or a battery pack.

[0080] The batteries provided in the embodiments of the present application are suitable for various battery-using electrical devices, such as battery vehicles, electric toys, electric tools, vehicles, ships, and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Since the batteries provided in the embodiments of the present application are not prone to arcing or violent energy release between high-voltage interfaces after the coolant leaks and immerses the internal high-voltage devices, the safety performance can be improved, thereby improving the reliability of the batteries and electrical devices.

[0081] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a battery car, an electric toy, an electric tool, a vehicle, a ship, and a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0082] For the convenience of description, the following embodiments are described by taking an electrical device according to an embodiment of the present application as an example.

[0083] like Figure 8As shown, some embodiments of the power-consuming device provided in the present application are vehicles 1000, which can be fuel vehicles, gas vehicles or new energy vehicles. The new energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles, etc. A battery 100 is arranged inside the vehicle, and the battery can be arranged at the bottom, head or tail of the vehicle. The battery can be used to power the vehicle, for example, the battery can be used as an operating power source for the vehicle. The vehicle 1000 may also include a control unit 200 and a motor 300, and the control unit 200 is used to control the battery 100 to power the motor 300, for example, for the starting, navigation and working power requirements of the vehicle during driving.

[0084] In some embodiments of the present application, the battery can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0085] The following describes batteries provided by some embodiments of the present application in conjunction with the accompanying drawings.

[0086] Figure 1 A three-dimensional schematic diagram of a first structure of a battery provided in some embodiments of the present application; Figure 2 for Figure 1 Schematic diagram of the battery during the test; Figure 3 A perspective schematic diagram of a second structure of a battery provided in some embodiments of the present application; Figure 4 A three-dimensional schematic diagram of a third structure of a battery provided in some embodiments of the present application; Figure 5 A perspective schematic diagram of a fourth structure of a battery provided in some embodiments of the present application; Figure 6 A perspective schematic diagram of a fifth structure of a battery provided in some embodiments of the present application; Figure 7 A schematic three-dimensional diagram of a sixth structure of a battery provided for some embodiments of the present application.

[0087] See also Figures 1 to 7 The battery 100 provided in some embodiments of the present application includes a sealed box 3, a heat exchange plate 1, a battery cell 2, a detection component and a controller 7. The heat exchange plate 1 and the battery cell 2 are both arranged in the sealed box 3. The heat exchange plate 1 is arranged to contact the surface of at least one battery cell 2. A liquid heat exchange medium flows in the heat exchange plate 1. The detection component is arranged in the heat exchange plate to detect the real-time conductivity of the liquid heat exchange medium. The controller 7 is communicated with the detection component to obtain the real-time conductivity and alarm when the real-time conductivity exceeds a threshold.

[0088] The sealed box 3 is used to provide a storage space for the battery cell 2, and the sealed box 3 can adopt a variety of structures. In some embodiments, the sealed box 3 may include a first part and a second part, and the first part and the second part cover each other to jointly define a storage space for accommodating the battery cell 2. One of the first part and the second part can be a hollow structure with an opening on one side, and the other can be a plate-like structure, and the plate-like structure covers the opening of the hollow structure, so that the first part and the second part jointly define a storage space; the first part and the second part can also be hollow structures with an opening on one side, and the opening side of the first part covers the opening side of the second part. Of course, the box formed by the first part and the second part can be a variety of shapes, such as a cylinder, a cuboid, etc.

[0089] In the battery, there can be multiple battery cells 2, and the multiple battery cells 2 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 2 are both connected in series and in parallel. The multiple battery cells 2 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 2 is accommodated in the sealed box 3; of course, the battery can also be a battery module formed by connecting multiple battery cells 2 in series, in parallel, or in mixed connection, and then the multiple battery modules are connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the sealed box 3. The battery can also include other structures, for example, the battery can also include a busbar component for realizing electrical connection between the multiple battery cells 2.

[0090] Each battery cell 2 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 2 may be cylindrical, flat, rectangular or in other shapes.

[0091] The heat exchange plate 1 refers to a component that has a liquid heat exchange medium flowing inside and contacts the battery cell 2, and is used to exchange heat with the battery cell 2 to control the temperature of the battery cell 2. Without limitation, the heat exchange plate 1 is a plate-like structure with a circulation channel inside, and the circulation channel is used to circulate the liquid heat exchange medium. The temperature of the heat exchange plate 1 is changed by heat exchange between the liquid heat exchange medium and the inner wall of the heat exchange plate 1. The heat exchange plate 1 contacts the battery cell 2, and the two exchange heat to achieve temperature control of the battery cell 2. The heat exchange plate 1 can be made of a material with high thermal conductivity, such as but not limited to copper, aluminum, copper-aluminum composite materials, stainless steel, engineering plastics, etc.

[0092] The heat exchange plate 1 is provided with a liquid inlet and a liquid outlet, the liquid inlet is connected to the liquid inlet pipe 4, the other end of the liquid inlet pipe 4 passes through the outside of the sealed box 3 and is used to connect the liquid supply pipe. The liquid heat exchange medium is supplied into the heat exchange plate 1 through the liquid inlet pipe 4, and the liquid outlet is connected to the discharge pipe 5, the other end of the discharge pipe 5 passes through the outside of the sealed box 3 and is used to connect the discharge pipe. The liquid heat exchange medium after heat exchange in the heat exchange plate 1 is discharged through the discharge pipe, forming a flow circulation channel for the heat exchange plate 1. The discharged liquid heat exchange medium can be cooled by the water cooling circulation system and then flow into the heat exchange plate 1 again through the liquid inlet pipe 4, thereby realizing the recycling of the liquid heat exchange medium.

[0093] There can be multiple heat exchange plates 1, and the multiple heat exchange plates 1 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple heat exchange plates 1 are both connected in series and in parallel. The multiple heat exchange plates 1 can be directly connected in series, in parallel, or in mixed connection.

[0094] Conductivity refers to a measure of the material's ability to conduct electricity, indicating the ability of a material to pass current. It describes the degree of conductivity of a material or solution to current and is defined as the ratio of the current flowing through a unit area on a cross-section of a conductive material within a unit length to the applied electric field strength. Conductivity can be measured using the determination method described in GB / T6682 "Specifications and Test Methods for Water Used in Analytical Laboratories". It is generally believed that the higher the conductivity, the stronger the material's ability to conduct current, and the lower the conductivity, the lower the material's ability to conduct current. In existing battery thermal management systems, a coolant with a conductivity of 3000 μS / cm is usually used, which has high conductivity. In some embodiments of the present application, the conductivity of the liquid heat exchange medium is set to no more than 500 μS / cm, so that the conductivity of the coolant can be suppressed at a low level. After the liquid heat exchange medium leaks and immerses the high-voltage device 21, due to the low conductivity and low conductivity of the liquid heat exchange medium, the risk of fire or even explosion caused by violent energy release such as short-circuit discharge and arcing between the inner walls of the high-voltage zone 31 can be reduced.

[0095] In addition, the electrical conductivity of the liquid heat exchange medium does not exceed 500μS / cm, including the case where the electrical conductivity of the liquid heat exchange medium selected when manufacturing the battery does not exceed 500μS / cm, and also includes the case where the electrical conductivity of the liquid heat exchange medium increases due to repeated use during the use of the battery but does not exceed 500μS / cm. If the electrical conductivity of the liquid heat exchange medium increases to more than 500μS / cm due to repeated use, the electrical conductivity of no more than 500μS / cm can be regained by replacing the liquid heat exchange medium, etc.

[0096] Regarding the selection of liquid heat exchange medium, as long as it is suitable for heat exchange with battery cells and meets the conductivity provided in the embodiments of this application, this application has no special restrictions on it, and it can be homemade or purchased from the market. As specific examples, for example, polyol-based water-cooling liquids such as ethylene glycol coolant and glycerol water-cooling liquid, water-based coolant, etc. can be cited.

[0097] The threshold is the boundary value of the qualified range of the specified conductivity, which is the upper limit here. When it exceeds the threshold, it indicates that the conductivity is unqualified or not suitable for continued use. When it does not exceed the threshold, it indicates that the conductivity is qualified or can continue to be used. It should be noted that there is no lower limit for the conductivity of the coolant here, which means that the conductivity can be as low as possible, for example, 1μS / cm or even lower.

[0098] For example, a threshold value (i.e., the upper limit of conductivity) can be set for the detection result of the detection member. If the threshold value is exceeded (i.e., the detected conductivity is higher than the threshold value), it is determined that the conductivity of the coolant is too high and needs to be replaced or stopped. Here, the threshold value can be set to 500μS / cm, 400μS / cm, 300μS / cm, 200μS / cm, 100μS / cm, 70μS / cm, 60μS / cm, or 50μS / cm, which are not listed here one by one.

[0099] The alarm signal may be, but is not limited to, a sound, a display of over-limit text on a display interface, or a light of a specific color. Moreover, it is also convenient to send the reminder information to the electrical equipment to reliably remind the user.

[0100] In the battery provided in the embodiment of the present application, the detection element is used to detect the real-time conductivity of the liquid heat exchange medium, and the controller 7 is used to obtain the real-time conductivity measured by the detection element and to alarm when the real-time conductivity exceeds the threshold value. Therefore, the controller 7 can monitor the real-time conductivity of the liquid heat exchange medium and promptly prompt to replace the liquid heat exchange medium, thereby effectively reducing the risk of short circuit between the sealed box body 3 and the internal high-voltage device due to conduction of the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance, thereby improving the safety of the battery and even the electrical device using the battery.

[0101] In some embodiments of the present application, an insulating layer is provided on the inner wall of at least the high-voltage area 31 of the sealed box 3 .

[0102] It should be noted that the battery box is usually provided with battery cells, connecting bars for electrically connecting multiple battery cells, and other devices for inputting and outputting battery voltage. These devices can be called high-voltage devices relative to devices such as battery sampling circuits, and the area in the battery box where these high-voltage devices are provided is called a high-voltage zone. Since the liquid cooling plate is usually provided near the battery cells, in the event of a coolant leak, the coolant will usually accumulate in the high-voltage zone. In addition, most of the devices in the high-voltage zone are high-voltage devices, so spontaneous combustion or explosion usually occurs first in the high-voltage zone. Therefore, an insulating layer is provided at least on the inner wall of the high-voltage zone in the battery box.

[0103] The insulating layer is a structure made of insulating material and having a certain thickness and arranged on the inner wall surface of at least the high-voltage area 31 of the sealed box body 3. The arrangement of the insulating layer further increases the insulation in the space of the high-voltage area 31, and further reduces the risk of fire or even explosion caused by violent energy release such as short-circuit discharge and arcing between high-voltage interfaces. It is understandable that the sealed box body 3 can be provided with an insulating layer only on the inner wall of the high-voltage area 31, or on all inner walls of the sealed box body 3.

[0104] The battery provided in the embodiment of the present application has an insulating layer on the inner wall of at least the high-voltage area 31 of the sealed box 3. At the same time, the conductivity of the liquid heat exchange medium in the heat exchange plate 1 does not exceed 500 μS / cm, and the conductivity is relatively low. The insulating layer and the low-conductivity liquid heat exchange medium cooperate to effectively reduce the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 due to conduction of the liquid heat exchange medium, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0105] In order to explore the safety of the battery provided by the present application after the accidental leakage of the liquid heat exchange medium, Figure 1 The battery shown was designed for testing. Figure 2 , Figure 2 for Figure 1 Schematic diagram of the battery in the test. The test was conducted under the following conditions: the liquid heat exchange medium was ethylene glycol coolant, the temperature was 25°C, the sea level atmospheric pressure, the voltage of the battery in the fully charged state was 900V, and the battery was fully charged. The leakage location was the liquid inlet pipe 4 and / or the liquid discharge pipe 5, the coolant leakage was 20L, the leakage rate was 0.5L / min, and an insulating layer was set on the inner wall of the high pressure area 31 of the sealed box 3. Figure 2 As shown, the battery 100 is tilted 20° toward the high voltage device 21 (such as a bar) of the battery. Figure 2The dotted line in the figure indicates the liquid level of the coolant. After the coolant leaks from the sealed box 3 of the battery, it gathers in a corner of the sealed box 3. At least a portion of the high-voltage device 21 (such as the bar) may be immersed in the leaked coolant. Here, immersion includes partial or complete immersion of the high-voltage device 21 (such as the bar).

[0106] In addition, the fully charged state of a battery refers to the state in which the electrical energy stored in the battery reaches its maximum capacity, that is, the fully charged state. In this state, the battery can provide the maximum electrical energy carried by its designed capacity.

[0107] The test was conducted using coolants with conductivity of 700μS / cm, 600μS / cm, 500μS / cm, 400μS / cm, 300μS / cm, 100μS / cm, and 50μS / cm. The reference example was tested using a coolant with conductivity of 3000μS / cm. The test results are shown in Table 1.

[0108] Table 1

[0109]

[0110]

[0111] As can be seen from Table 1 above, after the coolant immerses at least a portion of the high-voltage device 21 in the high-voltage area 31 of the battery, the battery will experience a temperature rise. The main reason is that the insulation environment of the high-voltage bars at the positive and negative electrodes of the battery is destroyed. The coolant acts as a conductive medium, and the high-voltage bars at the positive and negative electrodes release energy through the coolant creepage. The higher the conductivity used, the higher the temperature of the high-voltage area 31 of the battery after being immersed in the coolant.

[0112] The mechanism of the above test results needs further study and we do not wish to be bound by any theory. However, the inventors have attempted to theoretically analyze the test results based on the following formula.

[0113]

[0114] Among them, P represents the discharge power after the high-voltage device is short-circuited; U represents the voltage difference of the high-voltage device; σ represents the conductivity of the coolant; A represents the electrode plate area; L represents the creepage distance of the coolant (the value of A / L is fixed for the same battery system).

[0115] It can be seen from the above table that for a battery using a conventional coolant with a conductivity of 3000 μS / cm, after 20 minutes of coolant leakage, a violent high-voltage arc occurs in the high-voltage device 21, causing the battery to catch fire and burn.

[0116] In the test groups with coolant conductivity of 700μS / cm and 600μS / cm, the battery pack with coolant conductivity higher than 500μS / cm will have a maximum temperature of over 130°C after the high-voltage device 21 is immersed in the coolant. After the high-voltage device 21 is immersed in the coolant for a period of time, severe short circuit phenomena such as arcing will occur, and eventually cause the battery to catch fire.

[0117] In the experimental group with a coolant conductivity of 500μS / cm, although the temperature rose and reached equilibrium at 115℃-120℃, the battery pack did not catch fire for a relatively long period of time. As the short-circuit temperature rise gradually depleted the battery power, the battery power gradually decreased to 0, and the battery lost the possibility of catching fire and failure. There was no fire or explosion during the whole process.

[0118] The test groups with coolant conductivity of 400μS / cm, 300μS / cm, 100μS / cm and 50μS / cm also experienced temperature rise, but the maximum temperature that could be reached (also called equilibrium temperature) was lower than the equilibrium temperature reached when the conductivity was, for example, 500μS / cm. In addition, the battery pack did not fail due to fire for a relatively long period of time, and eventually the battery power gradually decreased to 0, and the battery lost the possibility of failure due to fire, and there was no fire or explosion during the entire process. As the conductivity decreases, the maximum temperature that the battery pack can reach after the high-voltage device 21 is immersed gradually decreases, and the safety performance of the battery becomes higher and higher.

[0119] In summary, when the conductivity of the coolant does not exceed 500 μS / cm, even if the coolant leaks accidentally and comes into contact with the high-voltage device 21 of the battery, it is not likely to cause safety issues such as spontaneous combustion, fire and explosion of the battery.

[0120] In some embodiments, when the total voltage of the battery in a fully charged state does not exceed 900 V, the threshold value does not exceed 500 μS / cm.

[0121] According to some embodiments of the present application, when the total voltage of the battery is 900V in a fully charged state, the threshold value of the conductivity of the liquid heat exchange medium is set to but not limited to 500μS / cm, 400μS / cm, 300μS / cm, 200μS / cm, 100μS / cm or 50μS / cm, which are not listed one by one here.

[0122] Through the cooperation of the insulating layer and the low-conductivity liquid heat exchange medium, for batteries with a total voltage not exceeding 900V, the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be effectively reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance. Therefore, even if the total voltage in the fully charged state is as high as 900V, suitable coolant and coolant replacement conditions involving conductivity can be provided, thereby achieving a balance in terms of safety, manufacturing cost, and coolant service life.

[0123] In some embodiments, the threshold value does not exceed 100 μS / cm when the total voltage of the battery in a fully charged state does not exceed 1500 V.

[0124] According to some embodiments of the present application, optionally, when the total voltage of the battery is 1500V in a fully charged state, the threshold value of the conductivity of the liquid heat exchange medium is set to but not limited to 100μS / cm, 90μS / cm, 80μS / cm, 70μS / cm, 60μS / cm, 50μS / cm, which are not listed one by one here.

[0125] Through the cooperation of the insulating layer and the low-conductivity liquid heat exchange medium, for batteries with a total voltage not exceeding 1500V, the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be effectively reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance. Therefore, even if the total voltage in the fully charged state is as high as 1500V, suitable coolant and coolant replacement conditions involving conductivity can be provided, thereby achieving a balance in terms of safety, manufacturing cost, and coolant service life.

[0126] According to some embodiments of the present application, when the total voltage of the battery in a fully charged state is in the range of 900V to 1500V, the threshold value is in the range of 50 to 500 μS / cm.

[0127] According to the test data, when the total voltage of the fully charged battery increases from 900V to 1500V, in order to maintain the situation where the leaked coolant does not cause fire or explosion until the battery pack power is reduced to 0, the threshold value of the coolant conductivity is set to gradually decrease.

[0128] In addition, when setting the conductivity of the coolant, the conductivity can be set as low as possible to improve the safety of the battery; it can also be set higher within the range of not catching fire or exploding to extend the replacement cycle of the coolant. As a specific example, when designing and manufacturing a battery, for a battery with a voltage of 900V when fully charged, the conductivity of the coolant injected into the heat exchange plate can be set lower, for example, the conductivity does not exceed 5μS / cm, and the threshold value of the coolant conductivity is set to 500μS / cm. Once the conductivity of the coolant exceeds 500μS / cm, the condition for replacing the coolant is met, that is, for the battery, in its normal use state, the conductivity of the coolant does not exceed 500μS / cm.

[0129] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 500 μS / cm for batteries with a total voltage of 900V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0130] According to some embodiments of the present application, when the total voltage of the battery in a fully charged state is in the range of 1000V to 1500V, the threshold value may be in the range of 50 to 250 μS / cm.

[0131] According to some embodiments of the present application, when the total voltage of the battery is 1200V to 1500V in a fully charged state, the threshold value may be in the range of 50 to 200 μS / cm.

[0132] For a battery with a further higher total voltage in a fully charged state, the threshold value of the conductivity of its liquid heat exchange medium can be further reduced.

[0133] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 200 μS / cm for batteries with a total voltage of 1200V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0134] According to some embodiments of the present application, when the total voltage of the battery in a fully charged state is in the range of 900V to 1500V, the threshold value is in the range of 50 to 100 μS / cm.

[0135] In order to further improve the safety of the battery, the conductivity of the coolant can also be designed to be lower.

[0136] By setting the threshold value of the conductivity of the liquid heat exchange medium in the range of 50 to 100 μS / cm for batteries with a total voltage of 900V to 1500V in the fully charged state, good battery thermal management performance can be provided, and the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be further reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0137] In order to compare the above tests, a group of tests without an insulating layer were conducted. The test was conducted under the following conditions: the liquid heat exchange medium used ethylene glycol coolant, the temperature was 25°C, the atmospheric pressure at sea level, the voltage of the battery in a fully charged state was 900V, and the battery was fully charged. The leakage location was the liquid inlet pipe 4 and / or the liquid discharge pipe 5, the coolant leakage was 20L, and the leakage rate was 0.5L / min. The battery 100 is tilted 20° toward the side of the high-voltage device 21 (such as a bar piece) of the battery. After the coolant leaked inside the sealed box 3 of the battery, it gathered in a corner of the sealed box 3. At least a portion of the high-voltage device 21 (such as a bar piece) can be immersed in the leaked coolant. Here, immersion includes partial or complete immersion of the high-voltage device 21 (such as a bar piece).

[0138] The test was conducted using coolants with conductivity of 500 μS / cm, 400 μS / cm, 300 μS / cm, and 200 μS / cm. The test results are shown in Table 2.

[0139] Table 2

[0140]

[0141]

[0142] It can be seen from Table 2 above that when no insulating layer is provided on the inner wall of the high-voltage area 31, under the same total voltage, the conductivity of the coolant will not explode unless it is ≤300μS / cm. Compared with Table 1, it can be seen that when no insulating layer is provided, a lower conductivity is required to achieve the overall safety protection of the battery after the coolant leaks. It also proves that the provision of an insulating layer reduces the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 due to the coolant conduction, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0143] In order to explore the matching relationship between the total voltage and conductivity of the battery in a fully charged state and to improve the safety performance of the battery, a battery with a total voltage of 1500V in a fully charged state was used as a test device for testing. The test environment was a coolant temperature of 25°C, sea level atmospheric pressure, a total battery voltage of 1500V, and a fully charged battery. During the test, the leakage position was the inlet pipe 4 and / or the drain pipe 5, the coolant leakage was 20L, the leakage rate was 0.5L / min, and an insulating layer was set on the inner wall of the high-voltage area 31 of the sealed box 3. The battery is tilted 20° toward the side of the high-voltage device 21 to ensure that the coolant will gather in a corner of the sealed box 3 after leaking inside the battery, and the high-voltage device 21 in the battery can be immersed.

[0144] The conductivity of the coolant used in the test is 300μS / cm, 200μS / cm, 100μS / cm, and 50μS / cm. The test results are shown in Table 3 below.

[0145] Table 3

[0146]

[0147] It can be seen from Table 3 above that when the total voltage of the battery is increased to 1500V and the battery uses a coolant with a conductivity of 300μS / cm and 200μS / cm, the battery arcs and catches fire in the high-voltage area 31 after the coolant leaks for a period of time. When the battery uses a coolant of 100μS / cm and 50μS / cm, the battery does not catch fire or explode. That is, after the battery with a coolant of 50μS / cm≤conductivity≤100μS / cm fails due to coolant leakage, the battery does not catch fire or explode until the battery power is reduced to 0 due to a short circuit. This ensures that even if the coolant accidentally leaks and contacts the high-voltage components of the battery, it will not cause battery safety failure.

[0148] In order to further explore the threshold value of the conductivity of the water coolant corresponding to the battery with a total voltage between 900V and 1500V, the same experimental method and judgment criteria as the battery experiment with a total voltage of 900V are used. The test environment is a coolant temperature of 25°C and atmospheric pressure at sea level. The battery is fully charged. During the test, the leakage location is the inlet pipe 4 and / or the drain pipe 5, the coolant leakage is 20L, the leakage rate is 0.5L / min, and an insulating layer is set on the inner wall of the high-voltage area 31 of the sealed box 3. The battery is tilted 20° toward the side of the high-voltage device 21 to ensure that the coolant leaks inside the battery and gathers in a corner of the sealed box 3, which can submerge the high-voltage device 21 in the battery. Test pass standard: The battery does not catch fire or explode until the battery power is reduced to 0 due to a short circuit.

[0149] The test was conducted using a battery connection experimental device with voltages of 1000V, 1100V, 1200V, 1300V, and 1400V. The battery of each voltage was tested with coolants having conductivity of 300μS / cm, 250μS / cm, 200μS / cm, 150μS / cm, 100μS / cm, and 50μS / cm. The maximum conductivity of the coolant that can pass the test was obtained, and the results are summarized in Table 4 below.

[0150] Table 4

[0151]

[0152] It can be seen from Table 4 above that as the total voltage of the battery increases in a fully charged state, the safety threshold of the conductivity of the liquid heat exchange medium tends to decrease.

[0153] Based on the test results with total voltages of 900V, 1500V and 1000V-1400V, it can be seen that, under the premise that the battery does not catch fire or explode, the total voltage of the battery in a fully charged state and the threshold value of the conductivity of the liquid heat exchange medium are inversely correlated, that is, as the total voltage increases, the required threshold value of conductivity decreases.

[0154] In some embodiments, when the liquid heat exchange medium is in contact with the insulating layer of the sealed box body 3, the battery does not spontaneously combust until the power of the fully charged battery drops to a minimum power level, wherein the minimum power level includes a power level of 0.

[0155] Through such measurement conditions, the threshold value of the allowable conductivity of the coolant with lower safety risk under a certain total battery voltage can be determined, so that the coolant can be properly selected and the conditions for coolant replacement can be set, which solves the problem that the existing method of determining whether the coolant meets the requirements by measuring the length of the fire time cannot solve.

[0156] Therefore, even if the liquid heat exchange medium leaks and accumulates in the sealed box 3, the risk of short circuit between the sealed box 3 and the internal high-voltage device 21 caused by the liquid heat exchange medium can be effectively reduced, thereby effectively reducing the risk of battery fire and explosion while providing good battery thermal management performance.

[0157] According to some embodiments of the present application, optionally, the detection element includes a conductivity sensor 6, and the conductivity sensor 6 is disposed in the flow path of the liquid heat exchange medium to detect the conductivity of the liquid heat exchange medium.

[0158] The conductivity sensor 6 is a component for detecting the conductivity of the liquid heat exchange medium. When performing the detection, the conductivity sensor 6 needs to be in full contact with the liquid heat exchange medium. Therefore, it is set in the flow path of the liquid heat exchange medium. Specifically, the conductivity sensor 6 can be set in the internal channel of the liquid inlet pipe 4 or the liquid outlet pipe 5, so as to accurately detect the conductivity of the liquid heat exchange medium. Of course, the conductivity sensor 6 can also be set in other suitable positions.

[0159] By setting up a conductivity sensor, it is possible to accurately determine whether the conductivity of the liquid heat exchange medium exceeds the threshold value. If it exceeds the threshold value, a prompt to replace the liquid heat exchange medium is given in time, thereby effectively reducing the risk of short circuit between the sealed box body 3 and the internal high-voltage device 21 due to the conduction of the liquid heat exchange medium. This can effectively reduce the risk of battery fire and explosion while providing good battery thermal management performance, thereby improving the safety of the battery and even the electrical device using the battery.

[0160] The conductivity sensor may be an existing or commercially available one, and the present application has no particular limitation thereto.

[0161] According to some embodiments of the present application, the conductivity sensor 6 can detect the conductivity of the liquid heat exchange medium periodically every 12 hours, and convert it into an electrical signal and transmit it to the battery management system. When the detected conductivity exceeds the threshold, the battery management system will control the vehicle user interface to send an alarm signal, prompting the user to replace the liquid heat exchange medium with a qualified conductivity through a formal channel.

[0162] Through the cooperation between the battery management system and the conductivity sensor 6, the conductivity is automatically judged to be qualified or not, and the user is reminded conveniently and timely. Moreover, it is also convenient to send the reminder information to the power-consuming device so as to reliably remind the user.

[0163] According to some embodiments of the present application, optionally, an insulating layer is provided on the inner wall by pasting an insulating film on the inner wall.

[0164] The insulating film is attached to the inner wall of at least the high voltage area 31 of the sealed box 3 by an adhesive, so that the insulating film forms an insulating layer. When attached, the insulating film deforms adaptively with the shape of the inner wall, so that the insulating film fits tightly to the inner wall, forming an insulating layer with the same shape as the inner wall surface.

[0165] An insulating layer is formed on the inner wall by pasting an insulating film.

[0166] According to some embodiments of the present application, optionally, the insulating film includes at least one of a ceramic insulating composite tape, mica paper, and a polymer insulating film.

[0167] Ceramic insulation composite tape is an insulating material composed of ceramic fiber, resin and other materials. It has excellent insulation properties, high temperature resistance and corrosion resistance. Ceramic fiber has high electrical insulation properties, which makes the ceramic insulation composite tape have excellent insulation properties. The ceramic insulation composite tape can maintain good insulation properties in high temperature environments, thereby improving the high insulation properties of the insulation layer.

[0168] Mica paper, also known as mica insulation paper, is an insulating material made of mica sheets as the main material, with appropriate amounts of adhesives and fillers added, and made through processes such as dipping, coating, and drying. It has excellent insulation and mechanical properties and is an important insulating material for electrical equipment such as motors, transformers, and cables.

[0169] The polymer insulating film is a film made of polymer materials, including insulating films made of at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, polymer polypropylene, polyethylene and nylon.

[0170] According to some embodiments of the present application, optionally, an insulating layer is provided on the inner wall by spraying an insulating coating on the inner wall.

[0171] The insulating coating is sprayed on the inner wall of at least the high-voltage area of ​​the sealed box 3 by a spraying device, thereby forming an insulating layer on the inner wall. The insulating coating is directly sprayed on the inner wall, and its shape is formed according to the shape of the inner wall, forming an insulating layer with the same shape as the inner wall surface.

[0172] An insulating layer is formed on the inner wall by spraying an insulating coating.

[0173] According to some embodiments of the present application, optionally, the insulating coating includes an epoxy resin insulating material coating.

[0174] Epoxy resin is a high molecular polymer, which refers to a class of polymers containing more than two epoxy groups in the molecule. It is the polycondensation product of epichlorohydrin and bisphenol A or polyol. Due to the chemical activity of the epoxy group, it can be opened with a variety of compounds containing active hydrogen, cured and cross-linked to form a network structure, so it is a thermosetting resin. Epoxy resin has excellent physical, mechanical and electrical insulation properties, bonding properties with various materials, and the flexibility of its use process is not possessed by other thermosetting plastics. It can be made into coatings, composite materials, casting materials, adhesives, molding materials and injection molding materials.

[0175] The insulating layer is formed by spraying epoxy resin, so that the insulating layer has higher electrical insulation performance and physical mechanical properties.

[0176] According to some embodiments of the present application, optionally, an insulating layer is provided on the inner wall by installing an insulating liner on the inner wall.

[0177] The insulating liner is a structure made according to the shape of the inner wall of the sealed box body 3 and has the same shape as the inner wall of the sealed box body 3. The insulating liner is assembled on the inner wall of the sealed box body 3 to form an insulating layer with the same shape as the inner wall surface.

[0178] An insulating layer is formed on the inner wall by arranging an insulating liner.

[0179] According to some embodiments of the present application, optionally, the insulating liner includes an liner made of engineering plastic.

[0180] Engineering plastics are plastics that can be used as engineering materials and replace metals to manufacture machine parts. Engineering plastics have excellent comprehensive properties, high rigidity, low creep, high mechanical strength, good heat resistance, good electrical insulation, can be used for a long time in harsh chemical and physical environments, and can replace metals as engineering structural materials.

[0181] The insulating liner made of engineering plastics not only has high insulation performance, but also has strong mechanical properties.

[0182] According to some embodiments of the present application, optionally, the engineering plastic includes at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, high molecular weight polypropylene, polyethylene and nylon.

[0183] The above lists three ways to form the insulating layer. The insulating layer can be formed by any one or more of them.

[0184] According to some embodiments of the present application, optionally, the heat exchange plate 1 is bonded to the surface of at least one battery cell 2 by an adhesive. The adhesive includes a thermally conductive adhesive.

[0185] The adhesive is a preparation used to bond the heat exchange plate 1 and the battery cell 2 together, and examples thereof include epoxy resin adhesive, polyurethane adhesive, organic silicone adhesive, and the like.

[0186] The heat exchange plate 1 is connected to the battery cell 2 by bonding, which improves the stability of the contact between the two, thereby ensuring sufficient heat exchange. The adhesive includes a thermally conductive adhesive, which improves the sufficiency of heat exchange between the heat exchange plate and the battery cell, thereby improving the cooling effect.

[0187] See also Figure 1 and Figures 3 to 7 The surface of the battery cell 2 includes at least any one of the large surface of the battery cell 2 , the side surface of the battery cell 2 , the bottom surface of the battery cell 2 , and the top surface of the battery cell 2 .

[0188] in, Figure 1 and Figure 7The middle heat exchange plate 1 contacts the bottom surface of the battery cell 2; Figure 3 The middle heat exchange plate 1 contacts the top surface of the battery cell 2; Figure 4 The top and bottom surfaces of the middle battery cell 2 are both in contact with the heat exchange plate 1; Figure 5 and Figure 6 The middle heat exchange plate 1 is disposed between adjacent battery cells 2 and contacts the large surface of the battery cells 2 .

[0189] The contact surface between the heat exchange plate 1 and the battery cell 2 can be determined according to the structural layout in the sealed box 3, and the layout is diverse, which improves the rationality of the layout.

[0190] The surface of the heat exchange plate 1 contacting the battery cell 2 is the large surface of the heat exchange plate 1 , which improves the efficiency of heat exchange between the two.

[0191] According to some embodiments of the present application, optionally, Figure 1 and Figure 7 As shown, a plurality of heat exchange plates 1 are arranged side by side on the same plane and adhered to the bottom surface of the battery cell 2 .

[0192] According to some embodiments of the present application, optionally, Figure 3 As shown, a plurality of heat exchange plates 1 are arranged side by side on the same plane and adhered to the bottom surface of the battery cell 2 .

[0193] According to some embodiments of the present application, optionally, Figure 4 As shown, multiple heat exchange plates 1 are divided into two groups, multiple heat exchange plates 1 in the same group are arranged side by side on the same plane, and the two groups are respectively attached to the top and bottom surfaces of the battery cell 2. Both the top and bottom surfaces exchange heat with the heat exchange plates 1, which improves the cooling efficiency.

[0194] According to some embodiments of the present application, optionally, Figure 5 and Figure 6 As shown, a plurality of heat exchange plates 1 and a plurality of battery cells 2 are alternately arranged in sequence, so that, except for the two battery cells 2 at the two ends, the remaining battery cells 2 have two surfaces contacting the heat exchange plates 1, thereby improving the cooling efficiency.

[0195] According to some embodiments of the present application, optionally, the heat exchange plate 1 is bonded to the inner wall surface of the sealing box 3 by an adhesive.

[0196] The heat exchange plate 1 is bonded to the inner wall surface of the sealing box body 3 , and the two are fixedly connected, thereby achieving the fixation of the heat exchange plate 1 .

[0197] According to some embodiments of the present application, optionally, the adhesive includes thermally conductive glue.

[0198] The adhesive is a preparation for bonding the heat exchange plate 1 and the battery cell 2 and a preparation for bonding the heat exchange plate 1 and the sealing box 3 .

[0199] The adhesive includes a heat-conducting glue, which improves the adequacy of heat exchange between the heat exchange plate 1 and the battery cell 2, thereby improving the cooling effect.

[0200] According to some embodiments of the present application, optionally, the heat exchange plate 1 is a hollow and flat liquid cooling plate, and the liquid heat exchange medium flowing in the hollow inner cavity of the liquid cooling plate is a coolant.

[0201] The coolant is a liquid used to cool the battery cells 2, and it takes away the excess heat in the battery through its flow.

[0202] The heat exchange plate 1 is set as a hollow structure, which can accommodate as much coolant as possible, thereby improving the cooling effect. The heat exchange plate 1 is set as a flat structure, which is convenient for arrangement in the narrow space of the sealed box 3, and the flat structure makes the large surface larger, increasing the contact area between the heat exchange plate 1 and the battery cell 2, and improving the cooling effect.

[0203] According to some embodiments of the present application, optionally, a plurality of heat exchange plates 1 are provided, and the plurality of heat exchange plates 1 are arranged in parallel between the liquid inlet pipe 4 and the liquid discharge pipe 5 .

[0204] The plurality of heat exchange plates 1 are arranged in parallel with each other, and one end of each heat exchange plate 1 is connected to the liquid inlet pipe 4, and the other end is connected to the liquid outlet pipe 5, forming a parallel connection mode.

[0205] The parallel connection mode makes the temperature of the coolant in each heat exchange plate 1 more balanced, thereby improving the balance of cooling the multiple battery cells 2 .

[0206] According to some embodiments of the present application, optionally, one end of the liquid inlet pipe 4 connected to the heat exchange plate 1 is located inside the sealed box 3, and the other end passes through the outside of the sealed box 3, and this end is a reserved interface for connecting to the liquid outlet interface of an external water cooling circulation system, and the one end of the liquid discharge pipe 5 connected to the heat exchange plate 1 is located inside the sealed box 3, and the other end passes through the outside of the sealed box 3, and this end is a reserved interface for connecting to the liquid inlet interface of an external water cooling circulation system.

[0207] According to some embodiments of the present application, optionally, see Figure 5 The liquid inlet pipe 4 and the liquid discharge pipe 5 can pass through the same side of the sealed box 3, see Figure 6 The liquid inlet pipe 4 and the liquid discharge pipe 5 can also pass through the opposite sides of the sealed box body 3 respectively.

[0208] According to some embodiments of the present application, the present application further provides an electrical device, which includes the battery described in any one of the above schemes, and the battery is used to provide electrical energy to the electrical device.

[0209] The power-consuming device can be any of the above-mentioned devices or systems using batteries, such as Figure 8As shown, it may be a vehicle 1000 .

[0210] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application is described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery, characterized in that: include: Sealed box; At least one battery cell is disposed in the sealed box; A heat exchange plate is disposed in the sealed box and is arranged to contact the surface of at least one of the battery cells, and a liquid heat exchange medium flows in the heat exchange plate; A detection element, disposed in the heat exchange plate, for detecting the real-time conductivity of the liquid heat exchange medium; The controller is connected to the detection element for obtaining the real-time conductivity and alarming when the real-time conductivity exceeds a threshold value.

2. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state does not exceed 900 V, the threshold value does not exceed 500 μS / cm.

3. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state does not exceed 1500 V, the threshold value does not exceed 100 μS / cm.

4. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state is in the range of 900 V to 1500 V, the threshold value is in the range of 50 to 500 μS / cm.

5. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state is in the range of 1000V to 1500V, the threshold value is in the range of 50 to 250 μS / cm.

6. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state is in the range of 1200V to 1500V, the threshold value is in the range of 50 to 200 μS / cm.

7. The battery according to claim 1, characterized in that When the total voltage of the battery in a fully charged state is in the range of 900 V to 1500 V, the threshold value is in the range of 50 to 100 μS / cm.

8. The battery according to any one of claims 1 to 7, characterized in that: The detection element includes a conductivity sensor, which is arranged in the flow path of the liquid heat exchange medium and is used to detect the real-time conductivity of the liquid heat exchange medium.

9. The battery according to any one of claims 1 to 8, characterized in that: At least the inner wall of the high-voltage area of ​​the sealed box is provided with an insulating layer.

10. The battery according to claim 9, characterized in that In a state where the liquid heat exchange medium is in contact with the insulating layer of the sealed box, the battery does not spontaneously ignite until the power of the fully charged battery drops to a minimum power level, wherein the minimum power level includes a power level of 0.

11. The battery according to claim 9, characterized in that The insulating layer is provided on the inner wall by pasting an insulating film on the inner wall, or, The insulating layer is provided on the inner wall by spraying an insulating coating on the inner wall, or, The insulating layer is provided on the inner wall by installing an insulating liner on the inner wall.

12. The battery according to claim 11, characterized in that The insulating film includes at least one of a ceramic insulating composite tape, mica paper, and a polymer insulating film.

13. The battery according to claim 11, characterized in that The insulating liner includes an liner made of engineering plastics.

14. The battery according to claim 11, characterized in that The insulating coating comprises an epoxy resin insulating material coating.

15. The battery according to claim 12, characterized in that The polymer insulating film includes an insulating film made of at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, polymer polypropylene, polyethylene and nylon.

16. The battery according to claim 13, characterized in that The engineering plastic includes at least one of polyimide, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, polydimethylsiloxane, polyurethane, polyvinyl chloride, high molecular weight polypropylene, polyethylene and nylon.

17. The battery according to any one of claims 1 to 16, characterized in that The heat exchange plate is bonded to the surface of at least one of the battery cells by an adhesive. The adhesive includes thermally conductive glue.

18. The battery according to any one of claims 1 to 17, characterized in that The heat exchange plate is bonded to the inner wall surface of the sealed box body by an adhesive.

19. The battery according to any one of claims 1 to 18, characterized in that The heat exchange plate is a hollow and flat liquid cooling plate, and the liquid heat exchange medium flowing in the hollow inner cavity of the liquid cooling plate is a coolant.

20. The battery according to any one of claims 1 to 19, characterized in that The battery further includes a liquid inlet pipe and a liquid discharge pipe. A plurality of heat exchange plates are provided, and the plurality of heat exchange plates are connected in parallel between the liquid inlet pipe and the liquid discharge pipe.

21. An electrical device, characterized in that: The electrical device comprises the battery according to any one of claims 1 to 20 for providing electrical energy.

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