Lithium ion battery explosion protection device

Abstract

The present invention provides a lithium ion battery explosion protection device, which relates to the technical field of lithium ion batteries and is arranged on the periphery of the lithium ion battery, comprising a perforated heat-conducting metal layer arranged on the outer side of the lithium ion battery, the outer sides of the perforated heat-conducting metal layer are a heat-conducting flame-retardant layer and an outer heat-conducting layer in sequence, and the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer are connected by a low-melting-point heat-conducting metal, and a fluid flame-retardant material is stored in the heat-conducting flame-retardant layer; when the lithium ion battery is operating normally, the heat-conducting material provides a good heat dissipation channel for it; when the lithium ion battery explodes, after the low-melting-point heat-conducting metal between the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer melts, the fluid flame-retardant material flows to the surface of the lithium ion battery to prevent the lithium ion battery from further burning; after the fluid flame-retardant material flows out, it forms a heat-insulating air layer at its original position in the heat-conducting flame-retardant layer to prevent heat from being transferred from the lithium ion battery to the outermost layer, thereby preventing the outer heat-conducting layer from causing loss or damage due to high temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium ion batteries, and more specifically, to a lithium ion battery explosion protection device. Background Art

[0002] Energy storage is a key supporting technology for promoting energy transformation and carbon neutrality. Among them, lithium battery energy storage has the advantages of high energy density, low self-discharge, no memory effect, wide operating temperature range, fast charging and discharging, long battery life, low environmental pollution, and not restricted by natural conditions such as terrain. Industries such as new energy vehicles and consumer electronics have driven the rapid development of the lithium battery industry, laying a solid foundation for the development of the lithium battery energy storage industry.

[0003] As the most commonly used new energy storage method, lithium batteries have brought great convenience to people's production and life. However, the risk of lithium batteries exploding is relatively high. Electric vehicles and electric bicycle batteries exploding incidents occur from time to time. After the battery spontaneously ignites, it will generate a lot of heat and smoke, causing harm to people nearby. It may also cause fires and cause great losses. Factors that cause lithium batteries to explode include electrical factors such as overvoltage and overcurrent, mechanical factors such as impact causing thermal runaway, or lithium precipitation causing the risk of explosion. At present, the explosion protection of lithium batteries is mainly based on the principle of lithium batteries. Balanced control is used to prevent lithium batteries from overcurrent and overvoltage, and mechanical protection and other measures are used to prevent thermal runaway. However, these protection methods cannot completely prevent lithium batteries from exploding. Therefore, the prior art proposes a lithium-ion battery separator, including a separator substrate, a high-temperature resistant polymer layer arranged on the separator substrate, an inorganic nanoparticle layer and a flame retardant layer. The inorganic nanoparticle layer is arranged on the surface of the separator substrate and is in direct contact with the separator substrate. The flame retardant layer is located on the outermost layer of the lithium-ion battery separator, has good thermal stability and excellent flame retardant properties, and can effectively improve the safety of the battery. However, this method still has problems such as poor thermal insulation effect and easy to cause high temperature loss or damage. Summary of the invention

[0004] In order to solve the problem that the thermal insulation effect is poor and high temperature damage is easily caused during the flame retardant process of current lithium-ion batteries, the present invention proposes a lithium-ion battery explosion protection device. After the fluid flame retardant material flows to the surface of the lithium ions, an insulating air layer is formed at the original position to prevent the high heat generated by the explosion of the lithium-ion battery from being transmitted to the outside world, thereby suppressing further combustion of the lithium battery and preventing losses and damage caused by high temperature as much as possible.

[0005] In order to achieve the above technical effects, the technical solution of the present invention is as follows:

[0006] A lithium-ion battery explosion protection device is arranged on the periphery of the lithium-ion battery, comprising a perforated heat-conducting metal layer arranged on the outer side of the lithium-ion battery, the outer sides of the perforated heat-conducting metal layer are a heat-conducting flame-retardant layer and an outer heat-conducting layer in sequence, and the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer are connected by a low-melting-point heat-conducting metal, and a fluid flame-retardant material is stored in the heat-conducting flame-retardant layer; after the low-melting-point heat-conducting metal is melted, the fluid flame-retardant material flows to the surface of the lithium-ion battery, and the heat-conducting flame-retardant layer is converted into a heat-insulating air layer.

[0007] The technical solution is through sequentially connected perforated heat-conducting metal layer, heat-conducting flame-retardant layer and outer heat-conducting layer; when the lithium-ion battery is working normally, the heat-conducting material provides it with a good heat dissipation channel; when the lithium-ion battery explodes, after the low-melting-point heat-conducting metal between the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer melts, the fluid flame-retardant material flows to the surface of the lithium-ion battery to prevent the lithium-ion battery from further burning; after the fluid flame-retardant material flows out, it forms an insulating air layer at its original position in the heat-conducting flame-retardant layer to prevent heat from being transferred from the lithium-ion battery to the outermost layer, thereby preventing the high temperature of the outer heat-conducting layer from causing loss or damage.

[0008] Preferably, the low-melting-point thermally conductive metal is disposed between the perforated thermally conductive metal layer and the thermally conductive flame-retardant layer, or the low-melting-point thermally conductive metal is encapsulated in the holes of the perforated thermally conductive metal layer.

[0009] Here, when the lithium-ion battery explodes, the low-melting-point thermally conductive metal layer melts and flows into the holes of the perforated thermally conductive metal, or the low-melting-point thermally conductive metal in the holes melts, and the fluid flame retardant material loses the obstruction of the low-melting-point thermally conductive metal layer and flows through the perforated thermally conductive metal layer to the surface of the lithium-ion battery, preventing the lithium-ion battery from further burning.

[0010] Preferably, the perforated heat-conducting metal layer is wrapped around at least one outer side of the lithium-ion battery, thereby providing multi-directional protection against explosion of the lithium-ion battery and improving safety.

[0011] Preferably, a plurality of holes are provided on one side of the perforated heat-conducting metal layer connected to the heat-conducting flame-retardant layer, and the holes are interconnected to form a flow area for accommodating the fluid flame-retardant material.

[0012] Preferably, the perforated heat-conducting metal layer is provided with a jet port for releasing flames and high-temperature gases generated by the explosion of the lithium-ion battery.

[0013] Here, the flame and high-temperature gas generated by the explosion of the lithium-ion battery can be released through the designated nozzles, and the flame and high-temperature gas nozzles can be aimed at the ground or other open uninhabited areas.

[0014] Preferably, the fluid flame retardant material is a heat-conducting flame retardant liquid, or a heat-conducting flame-retardant gas, or a mixture of a heat-conducting flame retardant liquid and a heat-conducting flame-retardant gas; when a lithium-ion battery explodes, the low-melting-point thermally conductive metal melts, and the fluid flame retardant material passes through the holes of the perforated thermally conductive metal layer under the action of gravity and covers the surface of the lithium-ion battery, preventing the lithium-ion battery from further burning.

[0015] Preferably, a pressurizing device is also provided for applying pressure to the inside of the thermally conductive flame retardant layer when the lithium ion battery explodes, thereby accelerating the flow of the fluid flame retardant material to the surface of the lithium ion battery.

[0016] Preferably, the fluid flame retardant material is thermally conductive silicone, and the thermally conductive metal material can be steel, aluminum alloy, etc.

[0017] Here, since the thermally conductive silicone has good thermal conductivity and electrical insulation properties, when the lithium-ion battery is working normally, the thermally conductive silicone can form a heat dissipation channel together with the perforated thermally conductive metal layer and the outer thermally conductive layer, and conduct heat from the inside to the outside; when the lithium-ion battery explodes, the thermally conductive silicone, under the action of gravity, passes through the holes in the perforated thermally conductive metal layer and covers the surface of the lithium-ion battery, preventing the lithium-ion battery from further burning while blocking the current.

[0018] The present invention further provides a lithium ion battery, wherein the lithium ion battery explosion protection device is provided on the periphery of the lithium ion battery.

[0019] The present invention also proposes a vehicle with a battery, wherein the vehicle uses a lithium-ion battery for energy storage, and the lithium-ion battery is provided with the above-mentioned lithium-ion battery explosion protection device on the periphery.

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0021] The present invention provides a lithium ion battery explosion protection device, which is arranged on the periphery of the lithium ion battery, comprising a perforated heat-conducting metal layer arranged on the outer side of the lithium ion battery, the outer sides of the perforated heat-conducting metal layer are successively a heat-conducting flame-retardant layer and an outer heat-conducting layer, and the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer are connected by a low-melting-point heat-conducting metal, and a fluid flame-retardant material is stored in the heat-conducting flame-retardant layer; when the lithium ion battery works normally, the heat-conducting material provides a good heat dissipation channel for it; when the lithium ion battery explodes, after the low-melting-point heat-conducting metal between the perforated heat-conducting metal layer and the heat-conducting flame-retardant layer melts, the fluid flame-retardant material flows to the surface of the lithium ion battery to prevent the lithium ion battery from further burning; after the fluid flame-retardant material flows out, it forms a heat-insulating air layer at its original position in the heat-conducting flame-retardant layer to prevent heat from being transferred from the lithium ion battery to the outermost layer, thereby preventing the outer heat-conducting layer from causing loss or damage due to high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A schematic diagram showing the structure of a lithium-ion battery explosion protection device proposed in Example 1 of the present invention;

[0023] Figure 2 A schematic diagram showing the structure of another lithium-ion battery explosion protection device proposed in Example 1 of the present invention;

[0024] Figure 3 A schematic diagram showing the heat dissipation of the lithium-ion battery explosion protection device in Embodiment 2 of the present invention when the lithium-ion battery is operating normally;

[0025] Figure 4 A schematic diagram showing heat conduction of the lithium-ion battery explosion protection device in Example 2 of the present invention when the lithium-ion battery explodes;

[0026] In the figure: 1. lithium-ion battery; 2. thermally conductive metal layer with holes; 21. injection nozzle; 3. thermally conductive flame-retardant layer; 4. outer thermally conductive layer; 5. low-melting-point thermally conductive metal. DETAILED DESCRIPTION

[0027] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0028] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated. For those skilled in the art, it is understandable that some well-known content descriptions in the drawings may be omitted.

[0029] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0030] Example 1

[0031] The present embodiment proposes a lithium-ion battery explosion protection device, which is arranged on the periphery of the lithium-ion battery 1, comprising: a perforated thermally conductive metal layer 2 arranged on the outer side of the lithium-ion battery 1, the outer sides of the perforated thermally conductive metal layer 2 are respectively a thermally conductive flame-retardant layer 3 and an outer thermally conductive layer 4, and the perforated thermally conductive metal layer 2 and the thermally conductive flame-retardant layer 3 are connected by a low-melting-point thermally conductive metal 5; the perforated thermally conductive metal layer 2 and the outer thermally conductive layer 4 are both made of thermally conductive metal materials, and the thermally conductive metal materials can be steel, aluminum alloy, etc.; the thermally conductive flame-retardant layer 3 contains a fluid flame-retardant material; the melting point of the low-melting-point thermally conductive metal 5 needs to be significantly lower than the above-mentioned thermally conductive metal, and the specific material is determined according to the temperature at which protection is expected to start after the lithium-ion battery 1 explodes; after the low-melting-point thermally conductive metal 5 melts, the fluid flame-retardant material flows to the surface of the lithium-ion battery 1, and the thermally conductive flame-retardant layer 3 is converted into a thermally insulating air layer.

[0032] As an example, Figure 1 As shown, the low-melting-point thermally conductive metal 5 can be a layer of low-melting-point thermally conductive metal. When the lithium-ion battery explodes, the low-melting-point thermally conductive metal layer melts and flows into the holes of the thermally conductive metal with holes. As another embodiment, the low-melting-point thermally conductive metal 5 can also be encapsulated in the holes of the thermally conductive metal layer 2 with holes.

[0033] like Figure 2 As shown, as a preferred embodiment, the perforated heat-conducting metal layer is wrapped on at least one outer side of the lithium-ion battery 1, and a hole is provided on the side connected to the heat-conducting flame-retardant layer 3, so as to form a multi-directional protection against the explosion of the lithium-ion battery and improve safety. Furthermore, a plurality of holes can be provided, and the holes are interconnected to form a whole flow area for accommodating the fluid flame-retardant material.

[0034] The perforated heat-conducting metal layer 2 is provided with a jet port 21 for releasing the flame and high-temperature gas generated by the explosion of the lithium-ion battery 1. The flame and high-temperature gas generated by the explosion of the lithium-ion battery 1 can be released through the designated jet port 21. In this embodiment, the flame and high-temperature gas jet port 21 can be aimed at the ground or other open uninhabited areas to improve safety.

[0035] In actual application, the fluid flame retardant material can be a heat-conducting flame retardant liquid or a heat-conducting flame-retardant gas; as an embodiment, the fluid flame retardant material is selected to be thermally conductive silicone. The thermally conductive silicone is mainly composed of organic silicone, and is added with fillers, thermally conductive materials and other polymer materials. The silicone is mixed and has good thermal conductivity and electrical insulation properties. When the lithium ion battery 1 is working normally, the thermally conductive silicone can form a heat dissipation channel together with the perforated thermally conductive metal layer 2 and the outer thermally conductive layer 4, and conduct heat from the inside to the outside; when the lithium ion battery 1 explodes, the low-melting-point thermally conductive metal 5 melts, and the thermally conductive silicone in the thermally conductive flame retardant layer 2 passes through the holes of the perforated thermally conductive metal layer 2 under the action of gravity and covers the surface of the lithium ion battery 1, on the one hand preventing the lithium ion battery 1 from further burning, and on the other hand acting as an insulating material to block the current; in addition, the thermally conductive flame retardant liquid can also be selected to be silicone oil or other composite materials. As another embodiment, the fluid flame retardant material is a heat-conductive and flame-retardant gas. When the lithium-ion battery 1 explodes, the low-melting-point heat-conductive metal 5 melts, and the concentration of the heat-conductive and flame-retardant gas in the heat-conductive and flame-retardant layer 3 decreases, thereby preventing the high heat generated by the explosion of the lithium-ion battery 1 from being transmitted to the outside. As yet another embodiment, the fluid flame retardant material may also be a mixture of a heat-conductive and flame-retardant liquid and a heat-conductive and flame-retardant gas.

[0036] As a preferred embodiment, the lithium-ion battery explosion protection device is also provided with a pressurizing device connected to the interior of the thermally conductive flame-retardant layer 3. The pressurizing device can be a gas pressure pump, which is used to apply pressure to the interior of the thermally conductive flame-retardant layer 3 when the lithium-ion battery 1 explodes, thereby accelerating the flow of fluid flame-retardant material to the surface of the lithium-ion battery 1.

[0037] Example 2

[0038] In this embodiment, based on the lithium-ion battery explosion protection device described in Embodiment 1, the situations of lithium-ion batteries in different states are described.

[0039] When the lithium-ion battery 1 is operating normally, Figure 3 As shown, since the perforated thermally conductive metal layer 2, the thermally conductive flame-retardant layer 3 and the outer thermally conductive layer 4 of the lithium-ion battery explosion protection device are all made of thermally conductive metal materials such as steel, aluminum alloy, etc., the perforated thermally conductive metal layer 2, the thermally conductive flame-retardant layer 3 and the outer thermally conductive layer 4 provide a good heat dissipation channel, and the lithium-ion battery explosion protection device conducts heat from the inside to the outside and dissipates heat, preventing the lithium-ion battery 1 from malfunctioning due to excessive temperature rise.

[0040] When the lithium-ion battery 1 explodes, Figure 4As shown, the low-melting-point thermally conductive metal between the perforated thermally conductive metal layer 2 and the thermally conductive flame-retardant layer 3 melts 5 and flows out from the holes of the perforated thermally conductive metal 2; at this time, the fluid flame-retardant material in the thermally conductive flame-retardant layer 2 loses the obstruction of the low-melting-point thermally conductive metal 5, and passes through the holes of the perforated thermally conductive metal layer 2 under the action of gravity and covers the surface of the lithium-ion battery 1, preventing the lithium-ion battery 1 from further burning; further, pressure can be applied to the inside of the thermally conductive flame-retardant layer 2 by a pressurizing device, and the air pressure inside the thermally conductive flame-retardant layer 2 increases, so that the fluid flame-retardant material is simultaneously affected by gravity and pressure, and is accelerated to flow to the surface of the lithium-ion battery 1.

[0041] After the fluid flame retardant material flows out of the thermally conductive flame retardant layer 3, it forms an insulating air layer at its original position in the thermally conductive flame retardant layer 3, preventing heat from being transferred from the lithium ion battery 1 to the outermost layer, thereby preventing the outer thermally conductive layer 4 from being damaged or caused by high temperature.

[0042] In addition, the lithium-ion battery 1 will generate high temperature, heat and flames after combustion and explosion, causing the vehicle to burn. In this case, the flames and high-temperature gases generated by the combustion and explosion of the lithium-ion battery 1 are released through the designated injection port 21 on the perforated thermal conductive metal layer 2, such as Figure 2 As shown; in this embodiment, the flame and high-temperature gas injection port 21 can be aimed at the ground or other open uninhabited areas to further improve safety.

[0043] Example 3

[0044] The present embodiment provides a vehicle with a battery, wherein the vehicle uses a lithium-ion battery 1 for energy storage, and the lithium-ion battery 1 is provided with the above-mentioned lithium-ion battery explosion protection device on the periphery thereof, including a perforated heat-conducting metal layer 2 arranged on the outer side of the lithium-ion battery 1, and the outer sides of the perforated heat-conducting metal layer 2 are successively provided with a heat-conducting flame-retardant layer 3 and an outer heat-conducting layer 4, and the perforated heat-conducting metal layer 2 and the heat-conducting flame-retardant layer 3 are connected by a low-melting-point heat-conducting metal 5; the perforated heat-conducting metal layer 2 and the outer heat-conducting layer 4 are both made of heat-conducting metal materials, and the heat-conducting metal materials can be selected from steel, aluminum alloy, etc. etc.; there is fluid flame retardant material in the thermal conductive flame retardant layer 3; when the lithium ion battery 1 is working normally, the thermal conductive material provides it with a good heat dissipation channel; when the lithium ion battery 1 explodes, after the low-melting-point thermal conductive metal 5 between the perforated thermal conductive metal layer 2 and the thermal conductive flame retardant layer 3 melts, the fluid flame retardant material flows to the surface of the lithium ion battery 1 to prevent the lithium ion battery 1 from further burning; after the fluid flame retardant material flows out, it forms an insulating air layer at its original position in the thermal conductive flame retardant layer 3, preventing heat from being transferred from the lithium ion battery 1 to the outermost layer, preventing the high temperature of the outer thermal conductive layer 4 from causing loss or damage.

[0045] In this embodiment, the vehicle may be a vehicle that uses lithium-ion batteries for energy storage, including electric bicycles, electric motorcycles, electric cars, electric buses, super trams, etc.

[0046] This embodiment further provides a lithium-ion battery, and the lithium-ion battery explosion protection device mentioned above is arranged on the periphery of the lithium-ion battery.

[0047] In addition, the lithium-ion battery explosion protection device can also be applied to other batteries that may explode or vehicles with batteries to achieve similar battery explosion protection effects, which are not listed one by one here.

[0048] Obviously, the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A lithium-ion battery explosion protection device, arranged on the periphery of a lithium-ion battery (1), characterized in that: The invention comprises a perforated heat-conducting metal layer (2) arranged on the outer side of a lithium-ion battery (1), the outer sides of the perforated heat-conducting metal layer (2) are a heat-conducting flame-retardant layer (3) and an outer heat-conducting layer (4) in sequence, and the perforated heat-conducting metal layer (2) and the heat-conducting flame-retardant layer (3) are connected via a low-melting-point heat-conducting metal (5), and a fluid flame-retardant material is stored in the heat-conducting flame-retardant layer (3); The low-melting-point heat-conducting metal (5) is arranged between the perforated heat-conducting metal layer (2) and the heat-conducting flame-retardant layer (3), or the low-melting-point heat-conducting metal (5) is encapsulated in the holes of the perforated heat-conducting metal layer (2); the perforated heat-conducting metal layer (2) is wrapped around at least one outer side of the lithium-ion battery (1); a plurality of holes are arranged on a side of the perforated heat-conducting metal layer (2) connected to the heat-conducting flame-retardant layer (3), the holes are interconnected and form a flow area for accommodating a fluid flame-retardant material; the fluid flame-retardant material is a heat-conducting flame-retardant liquid, or a heat-conducting flame-retardant gas, or a mixture of a heat-conducting flame-retardant liquid and a heat-conducting flame-retardant gas; The lithium ion battery explosion protection device is also provided with a pressurizing device, which is used to apply pressure to the inside of the heat-conducting flame-retardant layer (3) when the lithium ion battery (1) explodes, thereby accelerating the flow of the fluid flame-retardant material to the surface of the lithium ion battery.

2. The lithium-ion battery explosion protection device according to claim 1, characterized in that: The perforated heat-conducting metal layer (2) is provided with a jet port (21) for releasing the flame and high-temperature gas generated by the explosion of the lithium-ion battery (1).

3. The lithium-ion battery explosion protection device according to claim 1, characterized in that: The fluid flame retardant material is thermally conductive silicone.

4. A lithium ion battery, characterized in that: The lithium-ion battery is provided with a lithium-ion battery explosion protection device as described in any one of claims 1 to 3 on the periphery of the lithium-ion battery.

5. A vehicle with a battery, wherein the vehicle uses a lithium-ion battery for energy storage, characterized in that: The lithium-ion battery is provided with a lithium-ion battery explosion protection device as described in any one of claims 1 to 3 on the periphery of the lithium-ion battery.

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