Soft package battery

Abstract

The utility model relates to the field of new energy automobiles, and discloses a soft package battery. The soft package battery comprises a shell, a battery module and a heat insulation piece, wherein the shell is provided with a pressure relief hole, the heat insulation part and the battery module are both arranged in the shell, the shell is divided into a containing cavity and a pressure relief cavity by the heat insulation part, the containing cavity is used for containing the battery module, the heat insulation part is provided with a first vent hole, and the pressure relief cavity is connected with the pressure relief hole. High-temperature gas and jet can flow into the pressure relief cavity through the first vent hole in the heat insulation piece and then are discharged out of the soft package battery through the pressure relief opening. The heat insulation piece comprises a mica heat insulation plate, so that the high temperature and impact of thermal runaway are effectively separated from the battery module, and the battery module is not influenced by thermal runaway products to explode. At least the part of the shell, which is opposite to the first vent hole, is made of a mica material, so that the impact of thermal runaway products can be effectively prevented, and the service life of the soft package battery is further prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, in particular to a soft-pack battery. Background Art

[0002] Pure electric new energy vehicles are the main direction of the future development of the world's automobiles, providing support for energy conservation, emission reduction and sustainable development. Soft-pack batteries are widely used due to their advantages of light weight and high energy density. However, when soft-pack batteries collide and experience thermal runaway, due to their own structure and composition, they are prone to combustion and explosion, resulting in the failure of the battery and the entire vehicle. Therefore, it is crucial to develop a soft-pack protection design that can effectively isolate heat propagation.

[0003] At present, an exhaust channel is designed inside the soft-pack battery to discharge hot air and ejecta from the exhaust channel when the battery module experiences thermal runaway, avoiding the combustion or explosion of the soft-pack battery. However, the temperature inside the exhaust channel is too high, easily synchronizing the high temperature to the battery module, resulting in the thermal runaway of the battery module and even the entire battery pack, and the explosion of the soft-pack battery; there will also be problems that the exhaust channel cannot withstand high temperature, high pressure and high impact when hot air and ejecta spray towards the exhaust channel. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a soft-pack battery, which can solve the problem that the existing design of the exhaust channel of the soft-pack battery cannot withstand the impact caused by thermal runaway and explodes, ensuring the stability of the soft-pack battery during thermal runaway.

[0005] With the above concept, the technical solution adopted by the utility model is as follows:

[0006] A soft-pack battery, comprising:

[0007] A housing, provided with a pressure relief port thereon;

[0008] A heat insulation member, disposed inside the housing, for dividing the inside of the housing into a containing cavity and a pressure relief cavity. The heat insulation member is provided with a first ventilation hole, and the pressure relief cavity is communicated with the pressure relief port;

[0009] A battery module, disposed in the containing cavity;

[0010] The heat insulation member includes a mica heat insulation board, and / or at least a part of the housing opposite to the first ventilation hole is made of mica material.

[0011] As a preferred technical solution of the soft-pack battery, the battery module includes a battery cell and an outer coating film covering the battery cell. The outer coating film includes a first thickness region and a second thickness region. The first thickness region is opposite to the first ventilation hole, and the thickness of the first thickness region is thinner than the thickness of the second thickness region.

[0012] As a preferred technical solution of the soft-pack battery, the housing includes a detachable upper cover and a lower cover. The heat insulation member and the lower cover enclose the pressure relief cavity, and the lower cover is made of mica material.

[0013] As a preferred technical solution of the soft-pack battery, the upper cover is made of mica material.

[0014] As a preferred technical solution of the soft-pack battery, the accommodation cavity and the pressure relief cavity are arranged along a first direction, the tabs of the battery module extend along a second direction, and the first direction is perpendicular to the second direction.

[0015] As a preferred technical solution of the soft-pack battery, the soft-pack battery further includes a heat dissipation assembly. The heat dissipation assembly is disposed between the battery module and the heat insulation member and is used for dissipating heat from the battery module.

[0016] A second ventilation hole is provided at a position corresponding to the first ventilation hole of the heat dissipation assembly, and the second ventilation hole is communicated with the first ventilation hole.

[0017] As a preferred technical solution of the soft-pack battery, the heat dissipation assembly includes a liquid cooling plate. A heat exchange flow channel is provided inside the liquid cooling plate for accommodating a heat exchange medium, and the liquid cooling plate is in heat exchange cooperation with the battery module.

[0018] As a preferred technical solution of the soft-pack battery, the heat dissipation assembly further includes a thermal conductive adhesive layer, and the thermal conductive adhesive layer bonds the battery module and the liquid cooling plate.

[0019] As a preferred technical solution of the soft-pack battery, pressure relief ports are provided at both ends of the housing.

[0020] As a preferred technical solution of the soft-pack battery, the soft-pack battery further includes pressure relief valves. The pressure relief valves correspond to the pressure relief ports one by one, and the pressure relief valves are disposed at the pressure relief ports.

[0021] The beneficial effects of the present utility model are as follows:

[0022] When a thermal runaway occurs in the soft-pack battery proposed by the present utility model, the high-temperature gas and ejecta ejected from the battery module are sprayed into the pressure relief cavity formed by the heat insulation member and the housing through the first ventilation hole. The heat insulation member can insulate the temperature between the pressure relief cavity and the accommodation cavity, avoiding the problem of the soft-pack battery explosion caused by synchronously transmitting the pressure relief cavity temperature to the accommodation cavity; the heat insulation member includes a mica heat insulation board, which can not only insulate the accommodation cavity during the thermal runaway of the soft-pack battery, but also resist the impact of the high-temperature gas and ejecta generated by the thermal runaway on the heat insulation member, extending the service life of the heat insulation member; the part of the housing facing the first ventilation hole is made of mica material, which can have stronger anti-impact ability when the thermal runaway products are sprayed into the pressure relief cavity through the first ventilation hole, avoiding the problem of shortening the service life of the soft-pack battery due to the poor anti-impact ability of the housing material. Description of the Drawings

[0023] Figure 1 This is the front view of the soft-pack battery provided by the present utility model.

[0024] In the figure:

[0025] 1. Upper cover; 2. Battery module; 3. Thermal conductive adhesive layer; 4. Liquid cooling plate; 5. Heat insulation part; 6. Lower cover; 7. First ventilation hole; 8. Second ventilation hole; 9. Pressure relief valve. Specific embodiments

[0026] To make the technical problems solved by the present utility model, the technical solutions adopted and the achieved technical effects clearer, the technical solutions of the present invention will be further described below with reference to the accompanying drawings and through specific embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only the parts related to the present invention are shown in the drawings, rather than all of them.

[0027] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication 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 present invention can be understood according to specific circumstances.

[0028] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the non-direct contact between the first and second features but through other features therebetween. Moreover, the first feature being "above", "above and over", and "on the top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "below and under", and "under the bottom of" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0029] In the description of the present embodiment, the orientation or positional relationship such as "above", "below", "left", and "right" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0030] The technical solution of the present utility model will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0031] As Figure 1 shown, this embodiment provides a soft-pack battery including a housing, a heat insulation member 5, and a battery module 2. The heat insulation member 5 is disposed inside the housing, dividing the housing into a receiving cavity and a pressure relief cavity. The battery module 2 is placed in the receiving cavity. The heat insulation member 5 is provided with a first ventilation hole 7, and the housing is provided with a pressure relief port. The pressure relief cavity is communicated with the pressure relief port. When the battery module 2 undergoes thermal runaway, the high-temperature gas and ejecta generated by the battery module 2 can be discharged into the pressure relief cavity through the first ventilation hole 7, and then flow from the pressure relief cavity to the pressure relief hole. Finally, the high-temperature gas and ejecta generated by the thermal runaway of the soft-pack battery are discharged from the pressure relief hole to the outside of the soft-pack battery, avoiding explosion caused by the diffusion of the thermal runaway products around the battery module 2. The heat insulation member 5 includes a mica heat insulation board, which can separate the heat transfer between the receiving cavity and the pressure relief cavity, so as to prevent the heat in the pressure relief cavity into which the high-temperature gas and ejecta are discharged from being transferred back to the battery module 2 again, causing the battery module 2 to undergo thermal runaway again, resulting in continuous expansion of the soft-pack battery, or even explosion of the soft-pack battery. At the same time, because the mica board has good impact resistance, the heat insulation member 5 includes a mica heat insulation board, which will not be easily damaged when the high-temperature gas and ejecta are sprayed into the pressure relief cavity, thereby protecting the safety of the battery module 2, and can also ensure the integrity of the structure of the pressure relief cavity, enabling the pressure relief cavity to flow normally, thereby extending the service life of the soft-pack battery.

[0032] Since the spraying intensity is relatively large when the high-temperature gas and ejecta are sprayed from the inside of the battery module 2 into the pressure relief cavity, at least the part of the housing facing the first ventilation hole 7 can be made of a high-temperature resistant and impact-resistant material to resist the impact of the high-temperature gas and ejecta. The high-temperature resistant and impact-resistant material is generally a high-silica oxygen glass fiber material, but in this embodiment, mica material is selected. Using mica material to make this part can achieve the protection effect with a thinner thickness compared to using high-silica oxygen glass fiber material to make this part, resist the impact of the high-temperature gas and ejecta generated by thermal runaway, and protect the safety of the soft-pack battery.

[0033] Preferably, the mica material of at least the part of the housing facing the first ventilation hole 7 can be an impact-resistant mica board. The impact-resistant mica board is a mica board with a mechanical impact strength above 15 KJ / ㎡. To make the impacted part have higher impact resistance, the mica material of at least the part of the housing facing the first ventilation hole 7 in this embodiment can be an impact-resistant mica board with a mechanical impact strength reaching 20 KJ / ㎡.

[0034] In other embodiments, it is possible to only provide that the heat insulation member 5 includes a mica heat insulation board, or only make at least the part of the housing facing the first ventilation hole 7 from a high-temperature resistant and impact-resistant material.

[0035] As Figure 1As shown, the battery module 2 includes battery cells and an outer film covering the battery cells. The outer film includes a first thickness region and a second thickness region, and the first thickness region is aligned with the first vent hole 7. The thickness of the first thickness region is thinner than that of the second thickness region. By setting the battery module 2 in this way, when thermal runaway occurs in the battery module, the first thickness region will be first broken open, and the high-temperature gas and ejecta generated by thermal runaway can directly enter the pressure relief chamber through the first vent hole 7, avoiding the situation that the second thickness region is broken open first during thermal runaway, resulting in excessive high-temperature gas and ejecta in the accommodation chamber, causing secondary thermal runaway and even explosion of the soft-pack battery.

[0036] Optionally, the housing can be a detachable housing or a non-detachable housing. For more convenient detection of the parts inside the soft-pack battery in the future, in this embodiment, the housing is preferably a detachable housing.

[0037] Specifically, as Figure 1 shown, the housing includes an upper cover 1 and a lower cover 6 that are detachably connected. The lower cover 6 and the heat insulation member 5 enclose a pressure relief chamber. The lower cover 6 can be made of materials with high temperature resistance and impact resistance. Usually, high-silica glass fiber materials are used. However, in this embodiment, the lower cover 6 of the housing is made of mica material. Using mica material to make the lower cover 6 can achieve the protection effect with a thinner thickness than the lower cover 6 made of high-silica glass fiber material, resist the impact of high-temperature gas and ejecta generated by thermal runaway, and protect the safety of the soft-pack battery.

[0038] Preferably, the mica material selected for the lower cover can be impact-resistant mica board. In this embodiment, the lower cover 6 can be a mica board with a mechanical impact resistance of up to 20 KJ / ㎡.

[0039] Optionally, the material of the upper cover 1 of the housing also needs to be selected from materials with certain high temperature resistance and impact resistance, such as polyether ketone, high-silica glass fiber, and mica, etc., to prevent the situation where the heat insulation member 5 fails and high-temperature gas and ejecta flow into the entire housing. In this embodiment, mica is selected as the material of the upper cover 1 of the housing.

[0040] Specifically, as Figure 1 shown, the accommodation chamber and the pressure relief chamber are arranged along the first direction, the tabs of the battery module 2 extend along the second direction, the first direction is perpendicular to the second direction, and the heat insulation member 5 extends along the second direction to the inner wall of the housing, which can separate the accommodation chamber and the pressure relief chamber. Once thermal runaway occurs in the battery module, it can be quickly discharged in a specified direction through the optimal channel.

[0041] Specifically, as Figure 1As shown in the figure, in order to dissipate heat from the battery module 2, the soft-pack battery further includes a heat dissipation component, which is disposed between the battery module 2 and the heat insulation plate. To ensure that when the battery module 2 undergoes thermal runaway, high-temperature gases and ejecta can be sprayed into the pressure relief chamber, a second ventilation hole 8 is provided at a position corresponding to the first ventilation hole 7 of the heat dissipation component, and the second ventilation hole 8 is communicated with the first ventilation hole 7.

[0042] More specifically, as Figure 1 shown, the number of the first ventilation holes 7 provided in the heat insulation member 5 and the number of the second ventilation holes 8 provided in the heat dissipation component are not limited, but should not be set too many or too few. If the first ventilation holes 7 and the second ventilation holes 8 are set too many, the heat insulation function of the heat insulation member 5 and the heat dissipation function of the heat dissipation component will fail due to too many holes provided in the heat insulation member 5 and the heat dissipation component; if the first ventilation holes 7 and the second ventilation holes 8 are set too few, a large amount of high-temperature gases and ejecta accumulated in the battery module 2 cannot be discharged through the first ventilation holes 7 and the second ventilation holes 8, resulting in the expansion and explosion of the battery module 2 and even the entire soft-pack battery. To ensure that the heat insulation member 5 and the heat dissipation component do not fail and to avoid the explosion of the soft-pack battery, in this embodiment, two first ventilation holes 7 are provided in the heat insulation member 5 along the second direction, and two second ventilation holes 8 are provided in the heat dissipation component at positions corresponding to the above two first ventilation holes 7, and each corresponding ventilation hole is communicated, providing a channel for the high-temperature gases and ejecta generated after thermal runaway to be sprayed into the pressure relief chamber.

[0043] Optionally, the heat dissipation component includes a cooling plate for heat exchange cooperation with the battery module 2. The cooling plate can be an air-cooled plate, a liquid-cooled plate 4, etc. In this embodiment, the liquid-cooled plate 4 is selected to dissipate heat from the battery module 2.

[0044] Further, a heat exchange flow channel is provided in the liquid-cooled plate 4 for accommodating a heat exchange medium. The cooling medium is introduced into the heat exchange flow channel from the heat exchange flow channel inlet. After the battery module 2 is cooled through the heat exchange between the liquid-cooled plate 4 and the battery module 2, the cooling medium in the heat exchange flow channel will be pushed out of the heat exchange flow channel by the subsequent cooling medium introduced into the heat exchange flow channel, and thus the cooling medium is continuously introduced to perform heat exchange cooperation with the battery module 2.

[0045] Optionally, both the heat exchange flow channel inlet and the heat exchange flow channel outlet are provided on the housing, so that the staff can control the liquid-cooled plate 4 outside the housing.

[0046] Optionally, as Figure 1 shown, the heat dissipation component further includes a thermal conductive adhesive layer 3, which bonds the battery module 2 and the liquid-cooled plate 4. By providing the thermal conductive adhesive layer 3 between the liquid-cooled plate 4 and the battery module 2, the effect of improving the heat transfer between the battery module 2 and the liquid-cooled plate 4 is achieved, which is more beneficial to dissipating heat from the battery module 2.

[0047] Optionally, in order to enable the high-temperature gas and ejecta in the pressure relief chamber to be discharged outside the soft-pack battery more quickly, a pressure relief port is provided at each end of the housing for discharging the thermal runaway products.

[0048] In order to enable the soft-pack battery to selectively discharge the gas in the pressure relief chamber, the soft-pack battery further includes a pressure relief valve 9. The pressure relief valve 9 can be a spring-loaded pressure valve, a lever-type pressure valve, a pilot-operated pressure valve, and so on.

[0049] Furthermore, as Figure 1 described above, the number of the pressure relief valves 9 is equal to the number of the pressure relief ports, and the pressure relief valves 9 are arranged at the pressure relief ports and cooperate with the pressure relief ports.

[0050] When the battery module 2 has a thermal runaway, the high-temperature gas and ejecta generated by the thermal runaway are sprayed into the pressure relief chamber through the first ventilation hole 7 and the second ventilation hole 8. Due to the provision of the heat dissipation component and the heat insulation member 5, the battery module 2 will not be affected by the high heat in the pressure relief chamber. Moreover, the heat dissipation component even cools the battery module 2 to weaken the intensity of the thermal runaway. When the thermal runaway products are sprayed into the pressure relief chamber, the pressure relief valves 9 at the pressure relief ports are opened, and the pressure relief products will be discharged outside the soft-pack battery through the pressure relief ports. Also, due to the impact resistance of the material of the pressure relief chamber, the service life of the battery is guaranteed.

[0051] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill 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 enumerate all the implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A soft pack battery, characterized in that: include: A housing, wherein a pressure relief port is provided on the housing; A heat insulating member (5) is arranged in the shell, the heat insulating member (5) is used to separate the shell into a containing chamber and a pressure relief chamber, the heat insulating member (5) is provided with a first vent hole (7), and the pressure relief chamber is connected to the pressure relief port; A battery module (2) is arranged in the accommodating cavity; The thermal insulation member (5) comprises a mica thermal insulation board, and / or, At least the portion of the shell directly facing the first vent hole (7) is made of mica material.

2. The soft pack battery according to claim 1, characterized in that: The battery module (2) comprises a battery cell and an outer film covering the battery cell, the outer film comprising a first thickness region and a second thickness region, the first thickness region is directly opposite to the first vent hole (7), and the thickness of the first thickness region is thinner than the thickness of the second thickness region.

3. The soft pack battery according to claim 1, characterized in that: The shell comprises a detachable upper cover (1) and a lower cover (6); the heat insulating member (5) and the lower cover (6) enclose the pressure relief chamber; and the lower cover (6) is made of mica material.

4. The soft pack battery according to claim 3, characterized in that: The upper cover (1) is made of mica material.

5. The soft pack battery according to any one of claims 1 to 4, characterized in that: The accommodating cavity and the pressure relief cavity are arranged along a first direction, the pole ear of the battery module (2) extends along a second direction, and the first direction is perpendicular to the second direction.

6. The soft pack battery according to any one of claims 1 to 4, characterized in that: The soft-pack battery further comprises a heat dissipation component, which is arranged between the battery module (2) and the heat insulation component (5) and is used to dissipate heat from the battery module (2); A second vent hole (8) is provided at a position of the heat dissipation component corresponding to the first vent hole (7), and the second vent hole (8) is communicated with the first vent hole (7).

7. The soft pack battery according to claim 6, characterized in that: The heat dissipation component comprises a liquid cooling plate (4), a heat exchange channel is provided in the liquid cooling plate (4), the heat exchange channel is used to accommodate a heat exchange medium, and the liquid cooling plate (4) cooperates with the battery module (2) in heat exchange.

8. The soft pack battery according to claim 7, characterized in that: The heat dissipation component further comprises a heat conductive adhesive layer (3), and the heat conductive adhesive layer (3) is bonded to the battery module (2) and the liquid cooling plate (4).

9. The soft pack battery according to any one of claims 1 to 4, characterized in that: The pressure relief ports are disposed at both ends of the shell.

10. The soft pack battery according to claim 9, characterized in that: The soft-pack battery further comprises a pressure relief valve (9), the pressure relief valve (9) corresponds to the pressure relief port one by one, and the pressure relief valve (9) is arranged at the pressure relief port.

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