Battery pack and powered device

Abstract

The application provides a battery pack, comprising a box, a battery monomer and a heat insulation pad, the box comprises a bottom plate and a support arranged on the bottom plate; the battery monomer is arranged in the box, the end of the battery monomer is arranged on the support, and the first main body part of the battery monomer comprises a first side wall facing the bottom plate; the heat insulation pad is arranged on the first side wall, and a first channel is arranged between the heat insulation pad and the bottom plate, and the heat conductivity coefficient of the heat insulation pad is less than 0.1 W / (m.K). By arranging the heat insulation pad on the first side wall of the battery monomer, and the heat conductivity coefficient of the heat insulation pad being less than 0.1 W / (m.K), when thermal runaway occurs in a certain battery monomer, the high-temperature gas of the thermal runaway enters the first channel, and when the high-temperature gas of the thermal runaway flows in the first channel and contacts the battery monomer adjacent thereto, the heat transfer is blocked by the heat insulation pad, so that the temperature of the battery monomer adjacent thereto does not sharply rise to cause thermal runaway, thereby avoiding the spread of thermal runaway.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment, specifically providing a battery pack and an electrical device. Background Technology

[0002] New energy vehicles have seen rapid development in recent years due to their environmental friendliness and low energy consumption, attracting many automakers to join the research and development of new energy vehicles. However, the battery, as the most crucial component of new energy vehicles, has a significant impact on their development, particularly regarding safety. Reports of spontaneous combustion and fires in new energy vehicles are frequent, which can seriously endanger personal safety and cause major fires.

[0003] In the field, it is common practice to install some venting channels inside the battery pack to allow the high-temperature gases from thermal runaway to escape from the pack. However, the problem of controlled thermal propagation still exists, which can lead to the entire battery pack spontaneously combusting. Summary of the Invention

[0004] To address the problem of thermal runaway propagation in existing technologies, this invention provides a battery pack comprising: a housing, battery cells, and a thermal insulation pad. The housing includes a base plate and a support member disposed on the base plate. The battery cells are disposed within the housing, with their ends disposed on the support member. The first main body of the battery cells includes a first sidewall facing the base plate. The thermal insulation pad is disposed on the first sidewall, and a first channel is provided between the thermal insulation pad and the base plate. The thermal conductivity of the thermal insulation pad is less than 0.1 W / (mK).

[0005] By setting a heat insulation pad on the first sidewall of the battery cell, and the heat insulation pad has a thermal conductivity of less than 0.1 W / (mK), when a battery cell experiences thermal runaway, the high-temperature gas from the thermal runaway enters the first channel. When the high-temperature gas from the thermal runaway flows in the first channel and comes into contact with the adjacent battery cell, it is blocked from heat transfer by the heat insulation pad. Therefore, the temperature of the adjacent battery cell will not rise sharply and cause thermal runaway, thus avoiding the spread of thermal runaway.

[0006] In an optional embodiment of the present invention, the flame retardant rating of the aforementioned heat insulation pad is V0, and the melting point of the aforementioned heat insulation pad is greater than 1000°C. In the event of spontaneous combustion of a battery cell due to thermal runaway, the heat insulation pad can prevent the fire from spreading to adjacent battery cells, thereby preventing the entire battery pack from igniting.

[0007] In an optional embodiment of the present invention, a plurality of spaced weak points are provided on the heat insulation pad along the length of the battery cell. A battery cell experiencing thermal runaway can release the runaway gas into the first channel through these weak points. Three to seven weak points can be spaced apart along the length of a heat insulation pad. The ends of the heat insulation pad and the support member overlap, ensuring that the first sidewall of the battery cell 2 is completely covered by the heat insulation pad, thus preventing the spread of thermal runaway.

[0008] In an optional embodiment of the present invention, the heat insulation pad includes a second main body and a weak portion, wherein the thickness of the weak portion is less than the thickness of the second main body. By setting the thickness of the weak portion to be less than the thickness of the second main body, thermal runaway gas can break through the weak portion and enter the first channel.

[0009] In an optional technical solution of the present invention, the thickness H1 of the weak part and the thickness H2 of the second main body of the heat insulation pad satisfy: 1mm≤H2≤5mm, 0≤H1≤1mm.

[0010] In an optional embodiment of the present invention, the heat insulation pad includes a second main body and a weak portion, wherein the weak portion is a through hole. By providing a through hole for the weak portion, thermal runaway gas can directly enter the first channel through the through hole.

[0011] In an optional technical solution of the present invention, the shape of the through hole can be rectangular, circular, triangular, hexagonal or irregular.

[0012] In an optional technical solution of the present invention, the through hole is rectangular, and the length L1 and width L2 of the through hole satisfy: 20mm≤L1≤40mm, 0.1mm≤L2≤2mm. Designing the through hole as a slender rectangular hole allows high-pressure, high-temperature gas to easily enter the first channel after thermal runaway of a battery cell. Once in the larger first channel, the thermal runaway gas is diluted, thus preventing it from contacting adjacent battery cells through the through hole.

[0013] In an optional embodiment of the present invention, the heat insulation pad comprises an aerogel and an outer film encapsulating the aerogel, the outer film being insulating. The aerogel has excellent heat insulation and electrical insulation properties, and a high melting point; therefore, when disposed on the first sidewall of the battery cell, it can prevent thermal runaway from spreading to adjacent battery cells.

[0014] In an optional embodiment of the present invention, an adhesive strip is provided between the heat insulation pad and the first sidewall. The heat insulation pad can be bonded to the first sidewall of the battery cell using the adhesive strip.

[0015] In an optional technical solution of the present invention, the battery cell includes a sealing edge, and at least two adhesive strips are disposed between the heat insulation pad and the first sidewall, with the adhesive strips disposed on both sides of the sealing edge. By providing adhesive strips on both sides of the sealing edge to bond the heat insulation pad and the battery cell, accommodating space can be provided for the sealing edge. A heat insulation pad can be used to cover the first sidewall under two adjacent battery cells, with the sealing edges of the two battery cells disposed between the two adhesive strips, and the sealing edges of the two battery cells facing each other.

[0016] In an optional embodiment of the present invention, a fireproof layer is provided on the base plate, and the fireproof layer comprises a carbon ceramic material. After the thermal runaway gas enters the first channel, it will contact the base plate. The presence of the fireproof layer on the base plate prevents it from being damaged by the high-temperature gas during thermal runaway.

[0017] In an optional technical solution of the present invention, the aforementioned support member is provided with an air inlet and a second channel; the side wall of the aforementioned housing is provided with a third channel and a first explosion-proof valve; the aforementioned air inlet, the aforementioned second channel, the aforementioned third channel, and the aforementioned explosion-proof valve are sequentially connected. Thermal runaway gas enters the first channel and contacts the support member, then enters the second channel through the air inlet on the support member, then passes through the third channel connected to the second channel, and finally is discharged from the battery pack by the explosion-proof valve.

[0018] In an optional embodiment of the present invention, the air inlet is located on the side of the support member facing the bottom plate. This ensures that only when the gas pressure inside the chamber reaches a certain level, impacting the bottom plate and exposing the air inlet on the support member facing the bottom plate, can the thermal runaway gas enter the second channel for exhaust, thus avoiding the risk of exhaust in non-thermal runaway situations.

[0019] In an optional embodiment of the present invention, a second explosion-proof valve is provided on the housing, and the second explosion-proof valve is connected to the first channel. Thermal runaway gas entering the first channel can also be directly discharged from the battery pack through the second explosion-proof valve on the housing.

[0020] The present invention also provides an electrical device, which includes the battery pack described in the optional technical solutions above. By configuring the battery pack, the propagation of thermal runaway can be avoided. Attached Figure Description

[0021] Figure 1 It is a 3D view of the inside of the battery pack;

[0022] Figure 2 yes Figure 1 A bottom view excluding the base plate and supporting components;

[0023] Figure 3 yes Figure 1 The front view excluding the base plate and supporting components;

[0024] Figure 4 This is a schematic diagram of the heat insulation pad and the adhesive strip.

[0025] List of reference numerals in the attached diagram:

[0026] Box body 1, bottom plate 1.1, supporting component 1.2;

[0027] Battery cell 2, first sidewall 2.1, edge sealing 2.2;

[0028] Heat insulation pad 3, weak part 3.1, second main body part 3.2,

[0029] First Channel 4;

[0030] Thermal management component 5;

[0031] Buffer 6;

[0032] 7. Adhesive strip;

[0033] First adhesive 8. Detailed Implementation

[0034] The following describes optional embodiments of the present invention with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0035] In the description of this invention, it should be understood that the terms "distance", "width", "thickness", "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0036] In the description of this invention, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly defined.

[0037] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] To prevent the spread of thermal runaway in the battery pack, such as Figure 1-4As shown, the present invention provides a battery pack, including: a housing 1, a battery cell 2, and a heat insulation pad 3. The housing 1 includes a base plate 1.1 and a support member 1.2 disposed on the base plate 1.1; the battery cell 2 is disposed inside the housing 1, and the end of the battery cell 2 is disposed on the support member 1.2. The first main body of the battery cell 2 includes a first side wall 2.1 facing the base plate; the heat insulation pad 3 is disposed on the first side wall 2.1, and a first channel 4 is provided between the heat insulation pad 3 and the base plate 1.1. The thermal conductivity of the heat insulation pad 3 is less than 0.1 W / (mK). By setting a heat insulation pad 3 on the first sidewall 2.1 of the battery cell 2, and the thermal conductivity of the heat insulation pad 3 is less than 0.1 W / (mK), when a battery cell 2 experiences thermal runaway, the high-temperature gas from the thermal runaway enters the first channel 4. When the high-temperature gas from the thermal runaway flows in the first channel 4 and comes into contact with the adjacent battery cell 2, it is blocked from heat transfer by the heat insulation pad 3. Therefore, the temperature of the adjacent battery cell 2 will not rise sharply and cause thermal runaway, thereby avoiding the spread of thermal runaway.

[0039] In an optional embodiment of the present invention, the heat insulation pad 3 has a flame retardant rating of V0 and a melting point greater than 1000°C. In the event of spontaneous combustion of a thermally runaway battery cell 2, the heat insulation pad 3 can prevent the fire from spreading to adjacent battery cells 2, thereby preventing the entire battery pack from igniting.

[0040] In optional embodiments of the present invention, such as Figure 1 and Figure 3 As shown, the battery pack includes multiple battery cells 2 arranged along a first direction. The battery cells 2 can be pouch, prismatic, blade, or other types. The battery pack also includes a thermal management component 5 and a buffer component 6. The thermal management component 5 is disposed between two adjacent battery cells 2, improving the heat transfer efficiency of the battery cells 2. The surface with the largest area of ​​the battery cell 2 can be bonded to the thermal management component 5 using thermally conductive adhesive. The above arrangement of "battery cell-thermal management component-battery cell" is considered a cell group. A buffer component 6 is disposed between two adjacent cell groups, bonding the battery cell 2 and the buffer component 6. By setting the buffer component 6 and pre-setting a pre-tightening force, the expansion problem of the battery cell 2 can be solved. The battery cell 2, thermal management component 5, and buffer component 6 are all arranged along a first direction. Figure 1 Extending in the second direction, multiple battery cells 2 can also be arranged along the second direction and electrically connected. The thermal management component 5 can be a one-piece long cold plate, or it can be composed of multiple cold plates spliced ​​together. Along Figure 1 and Figure 3 The thermal management component 5 extends beyond the battery cell 2, so that when the battery cell 2 experiences thermal runaway, the thermal management component 5 can provide guidance for the runaway gas.

[0041] In optional embodiments of the present invention, such as Figure 4As shown, along the length of the battery cell 2, the heat insulation pad 3 has multiple spaced weak points 3.1. In the event of thermal runaway, the battery cell 2 can release the runaway gas into the first channel 4 through these weak points 3.1. Three to seven weak points 3.1 can be spaced apart along the length of the heat insulation pad 3. The ends of the heat insulation pad 3 overlap with the support member 1.2, ensuring that the first sidewall of the battery cell 2 is completely covered by the heat insulation pad, thus preventing the spread of thermal runaway.

[0042] In an optional embodiment of the present invention, the heat insulation pad 3 includes a second main body portion 3.2 and a weak portion 3.1, wherein the thickness of the weak portion 3.1 is less than the thickness of the second main body portion 3.2. By setting the thickness of the weak portion 3.1 to be less than the thickness of the second main body portion 3.2, thermal runaway gas can break through the weak portion 3.1 and enter the first channel 4.

[0043] In an optional embodiment of the present invention, the thickness H1 of the weak portion 3.1 and the thickness H2 of the second main body portion 3.2 of the heat insulation pad 3 satisfy: 1mm ≤ H2 ≤ 5mm, 0

[0044] In optional embodiments of the present invention, such as Figure 4 As shown, the heat insulation pad 3 includes a second main body 3.2 and a weak part 3.1, where the weak part 3.1 is a through hole. By making the weak part 3.1 a through hole, thermal runaway gas can directly enter the first channel 4 through the through hole. The shape of the through hole can be rectangular, circular, triangular, hexagonal, or irregular. When the through hole is rectangular, the length L1 and width L2 of the through hole satisfy: 20mm≤L1≤40mm, 0.1mm≤L2≤2mm. Designing the through hole as a slender rectangular hole allows high-pressure, high-temperature gas to easily enter the first channel 4 after thermal runaway of the battery cell 2. Upon entering the larger space of the first channel, the thermal runaway gas is diluted, thus preventing it from contacting adjacent battery cells 2 through the through hole. L2 can be 0.1mm, 0.5mm, 1mm, or 2mm, and L1 can be 20mm, 25mm, 30mm, 35mm, or 40mm.

[0045] In an optional embodiment of the invention, the heat insulation pad 3 includes an aerogel and an outer film encapsulating the aerogel. The outer film is insulating, for example, it can be PET. The aerogel has excellent heat insulation and electrical insulation properties and a high melting point. Therefore, when disposed on the first sidewall 2.1 of the battery cell 2, it can prevent thermal runaway from spreading to adjacent battery cells 2.

[0046] In optional embodiments of the present invention, such as​ Figure 4 As shown, an adhesive strip 7 can be provided between the heat insulation pad 3 and the first sidewall 2.1. The heat insulation pad 3 can be bonded to the first sidewall 2.1 of the battery cell 2 through the adhesive strip 7.

[0047] In optional embodiments of the present invention, such as Figure 3 As shown, the battery cell 2 includes a sealing edge 2.2, a heat insulation pad 3, and at least two adhesive strips 7 are disposed between the first sidewall 2.1 and the sealing edge 2.2. The adhesive strips 7 are located on both sides of the sealing edge 2.2. By using adhesive strips 7 on both sides of the sealing edge 2.2 to bond the heat insulation pad 3 and the battery cell 2, a space is provided for the sealing edge 2.2. A heat insulation pad 3 can be used to cover the first sidewall 2.1 under two adjacent battery cells 2. A buffer 6 is disposed between these two battery cells 2. The sealing edges 2.2 of the two battery cells 2 are disposed between the two adhesive strips 7, and the sealing edges 2.2 of the two battery cells 2 are arranged opposite each other, that is, the sealing edges 2.2 of the two battery cells 2 are bent towards each other onto the first sidewall 2.1 of the battery cell 2. Figure 2 As shown, the "battery cell 2-buffer 6-battery cell 2" covered by two heat insulation pads is set as a whole on the support 1.2. Specifically, it can be bonded to the support 1.2 by the first adhesive 8.

[0048] In an optional embodiment of the present invention, a fireproof layer is provided on the base plate 1.1. The fireproof layer comprises a carbon ceramic material and can be sprayed onto the base plate 1.1. After the thermal runaway gas enters the first channel 4, it will come into contact with the base plate 1.1. The fireproof layer on the base plate 1.1 can prevent the base plate 1.1 from being damaged by the high-temperature gas of thermal runaway.

[0049] In an optional embodiment of the present invention, the support member 1.2 is provided with an air inlet and a second channel; the side wall of the housing 1 is provided with a third channel and a first explosion-proof valve; the air inlet, the second channel, the third channel, and the explosion-proof valve are connected in sequence. After thermal runaway gas enters the first channel 4, it contacts the support member 1.2, enters the second channel through the air inlet on the support member 1.2, then passes through the third channel connected to the second channel, and finally exits the battery pack through the explosion-proof valve. After the thermal runaway gas passes through the above three channels, the temperature can be reduced, preventing the battery pack from being discharged with an open flame or excessively hot gas, thereby avoiding injury to the user.

[0050] In an optional embodiment of the present invention, the air inlet is located on the side of the support member 1.2 facing the bottom plate 1.1. This way, only when the air pressure inside the housing 1 reaches a certain level, impacting the bottom plate 1.1 and exposing the air inlet of the support member 1.2 facing the bottom plate 1.1, can the thermal runaway gas enter the second channel 4 for exhaust, thus avoiding the risk of exhaust in non-thermal runaway situations.

[0051] In an optional embodiment of the present invention, a second explosion-proof valve is provided on the housing 1, and the second explosion-proof valve is connected to the first channel 4. Thermal runaway gas entering the first channel 4 can also be directly discharged from the battery pack through the second explosion-proof valve on the housing 1.

[0052] The present invention also provides an electrical device, which includes the battery pack described in the optional embodiments above. The battery pack helps prevent thermal runaway propagation in the electrical device. This electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., while spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0053] The technical solutions of the present invention have been described in conjunction with the optional embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A battery pack, comprising: The housing includes a base plate and supporting members disposed on the base plate; A battery cell is disposed inside the housing, with its end disposed on the support member, and the first main body of the battery cell includes a first sidewall facing the bottom plate; A heat insulation pad is disposed on the first side wall, and a first channel is provided between the heat insulation pad and the base plate. The thermal conductivity of the heat insulation pad is less than 0.1 W / (mK). The support member is provided with an air inlet and a second channel; The air inlet is located on the side of the support member facing the base plate; The side wall of the enclosure is provided with a third channel and a first explosion-proof valve; The air inlet, the second channel, the third channel, and the explosion-proof valve are connected in sequence.

2. The battery pack as described in claim 1, characterized in that, The flame retardant rating of the heat insulation pad is V0.

3. The battery pack as described in claim 2, characterized in that, The heat insulation pad has a melting point greater than 1000℃.

4. The battery pack as described in any one of claims 1-3, characterized in that, Along the length of the battery cell, the heat insulation pad has multiple spaced weak points.

5. The battery pack as described in any one of claims 1-3, characterized in that, The heat insulation pad includes a second main body and a weak part, wherein the thickness of the weak part is less than the thickness of the second main body.

6. The battery pack as described in claim 5, characterized in that, The thickness H1 of the weak portion and the thickness H2 of the second main body portion satisfy: 1mm ≤ H2 ≤ 5mm, 0 <H1≤1mm。 7. The battery pack as described in any one of claims 1-3, characterized in that, The heat insulation pad includes a second main body and a weak part, wherein the weak part is a through hole.

8. The battery pack as described in claim 7, characterized in that, The through hole can be rectangular, circular, triangular, hexagonal, or irregular in shape.

9. The battery pack as described in claim 8, characterized in that, The through hole is rectangular, and the length L1 and width L2 of the through hole satisfy: 20mm≤L1≤40mm, 0.1mm≤L2≤2mm.

10. The battery pack according to any one of claims 1-3, characterized in that, The heat insulation pad includes an aerogel and an outer film encapsulating the aerogel, the outer film being insulating.

11. The battery pack as described in any one of claims 1-3, characterized in that, An adhesive strip is provided between the heat insulation pad and the first sidewall.

12. The battery pack as claimed in claim 11, characterized in that, The battery cell includes an edge seal, and at least two adhesive strips are provided between the heat insulation pad and the first sidewall, with the adhesive strips located on both sides of the edge seal.

13. The battery pack according to any one of claims 1-3, characterized in that, The base plate is provided with a fireproof layer, which contains carbon ceramic material.

14. The battery pack as claimed in claim 13, characterized in that, The enclosure is equipped with a second explosion-proof valve, which is connected to the first channel.

15. An electrical device comprising a battery pack as claimed in any one of claims 1 to 14.

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