Battery pack box body and battery pack

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery pack box body and a battery pack, the battery pack box body comprises a lower box body and protective end covers, the lower box body is provided with accommodating grooves, insulating colloid for fixing single batteries is filled between the accommodating grooves and the single batteries, and the protective end covers are in one-to-one correspondence with the accommodating grooves. The insulating colloid is connected with the protective end cover and the lower box body in a sealing manner, the failure temperature of the insulating colloid is smaller than the thermal runaway temperature of the single battery, the protective end cover is provided with a weakening structure, and the thickness of the weakening structure is smaller than that of other parts of the protective end cover. When thermal runaway occurs, high-temperature and high-pressure gas breaks through the weakening structure for pressure relief to achieve primary protection, and when the temperature is gradually increased to the failure temperature of the insulating colloid, the insulating colloid is melted, and the high-temperature and high-pressure gas breaks through the protection end cover for pressure relief to achieve secondary protection. And the safety during thermal runaway is ensured through double protection.

Description

Technical Field

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

[0002] The battery pack enclosure is the primary load-bearing component of the battery system, and its performance directly impacts the safety and stability of the battery system, as well as the performance of the entire vehicle. The battery pack enclosure must not only protect the internal components from external physical influences but also provide excellent sealing, typically meeting IP67 standards. This sealing effectively prevents moisture and dust intrusion, ensuring the battery's proper operation in a variety of environments.

[0003] However, after long-term cyclic charge and discharge use, the multiple batteries loaded in the battery pack will gradually produce high-temperature and high-pressure gas inside. In order to prevent the high-temperature and high-pressure gas from accumulating inside the battery and causing an explosion, an explosion-proof valve is usually installed on the battery so that the high-temperature and high-pressure gas inside the battery can break through the explosion-proof valve after accumulating to a certain level, thereby achieving the purpose of internal pressure relief of the battery.

[0004] However, since conventional battery pack cases have good sealing properties to prevent the intrusion of moisture and dust, when the high-temperature and high-pressure gas inside the battery breaks through the explosion-proof valve, the high-temperature and high-pressure gas will be directly discharged into the battery pack case and run around in the battery pack case, causing impact on other normally operating batteries in the battery pack case and the electronic control components inside the battery pack case, causing damage. Therefore, traditional battery pack cases have poor protection and safety when thermal runaway occurs. Utility Model Content

[0005] The purpose of the utility model is to provide a battery pack box and a battery pack with good protection and high safety.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In one aspect, a battery pack case is provided, wherein the battery pack case is used to install a plurality of single cells, and the battery pack case comprises:

[0008] A lower box body, wherein the lower box body is provided with a receiving groove, and the receiving groove and the single battery located in the receiving groove are filled with an insulating colloid for fixing the single battery;

[0009] A protective end cover, wherein the protective end cover corresponds to the accommodating groove one by one and closes the corresponding accommodating groove; the insulating colloid seals and connects the protective end cover and the lower box; the failure temperature of the insulating colloid is lower than the thermal runaway temperature of the single cell; the protective end cover is provided with a weakening structure; the thickness of the weakening structure is lower than the thickness of other parts of the protective end cover.

[0010] Optionally, the protective end cover includes a closing portion and an inserting portion, the closing portion is adhered to the lower box body and is used to close the receiving groove, and the inserting portion is inserted into the receiving groove and abuts against the single battery.

[0011] Optionally, the plug-in portion includes an annular protrusion extending from the surface of the closing portion in a direction approaching the single battery to form an exhaust channel on the inner side of the plug-in portion, and the weakening structure is provided in an area of ​​the closing portion surrounded by the exhaust channel.

[0012] Optionally, a limiting portion is further provided on the protective end cover, and the outer edge of the closing portion extends in a direction away from the central axis to form the limiting portion. A limiting groove is also provided on the surface where the lower box body and the closing portion are bonded, and the limiting portion is accommodated in the limiting groove.

[0013] Optionally, the protective end cover consisting of the closing portion, the plug-in portion and the limiting portion is integrally formed by an injection molding process.

[0014] Optionally, a protective fillet is provided at a corner of the limiting portion on a side away from the closing portion.

[0015] Optionally, there are multiple limiting portions, and the multiple limiting portions are evenly distributed on the outer edge of the closing portion.

[0016] Optionally, the weakening structure includes an annular groove formed on a side of the protective end cover facing the single battery cell.

[0017] Optionally, the cross-section of the annular groove is V-shaped or U-shaped.

[0018] On the other hand, a battery pack is provided, comprising a battery pack case as described in any one of the above items.

[0019] Beneficial effects of the utility model:

[0020] The utility model provides a battery pack case, which seals and connects the protective end cover and the lower case by utilizing an insulating colloid whose failure temperature is lower than the thermal runaway temperature of the single cell, and provides a weakening structure with a thickness less than that of other parts of the protective end cover, so that when thermal runaway occurs, due to the small thickness of the weakening structure, its structural strength is poor, so that the high-temperature and high-pressure gas can be discharged to the outside by breaking through the weakening structure, and the pressure is relieved once, thereby achieving a layer of protection. If the pressure relief requirement still cannot be met at this time, as the temperature gradually rises to the failure temperature of the insulating colloid, the insulating colloid melts, causing the bonding strength between the protective end cover and the lower case to gradually decrease, until the bonding force is less than the pressure of the high-temperature and high-pressure gas, the high-temperature and high-pressure gas will further break through the protective end cover and be discharged to the outside, and the pressure is relieved twice, thereby achieving double protection. The double pressure relief protection can ensure the smooth discharge of the high-temperature and high-pressure gas during thermal runaway, thereby improving the safety of the battery pack case.

[0021] The present utility model also provides a battery pack, which, by applying the above-mentioned battery pack case, can promptly discharge the high-temperature and high-pressure gas generated by thermal runaway to the outside when thermal runaway occurs, thereby avoiding the impact of thermal runaway on other components in the battery pack case, reducing the scope of damage, and reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is an assembly diagram of the battery pack box provided by the present utility model;

[0023] Figure 2 This is a structural exploded view of the battery pack box provided by the present invention;

[0024] Figure 3 This is a structural diagram of the lower box body in the battery pack box provided by the present invention;

[0025] Figure 4 This is a schematic structural diagram of the protective end cover in the battery pack box provided by the present invention;

[0026] Figure 5 It is a structural sectional view of the protective end cover in the battery pack box provided by the present invention.

[0027] In the picture:

[0028] 1. Lower box; 11. Accommodation slot; 12. Limiting slot;

[0029] 2. Protective end cover; 21. Weakened structure; 22. Closing part; 23. Connecting part; 24. Exhaust channel; 25. Limiting part; 26. Protective fillet. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0031] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0032] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0034] The battery pack enclosure is the primary load-bearing component of the battery system, and its performance directly impacts the safety and stability of the battery system, as well as the performance of the entire vehicle. The battery pack enclosure must not only protect the internal components from external physical influences but also provide excellent sealing, typically meeting IP67 standards. This sealing effectively prevents moisture and dust intrusion, ensuring the battery's proper operation in a variety of environments.

[0035] However, after long-term cyclic charge and discharge use, the multiple batteries loaded in the battery pack will gradually produce high-temperature and high-pressure gas inside. In order to prevent the high-temperature and high-pressure gas from accumulating inside the battery and causing an explosion, an explosion-proof valve is usually installed on the battery so that the high-temperature and high-pressure gas inside the battery can break through the explosion-proof valve after accumulating to a certain level, thereby achieving the purpose of internal pressure relief of the battery.

[0036] However, since conventional battery pack cases have good sealing properties to prevent the intrusion of moisture and dust, when the high-temperature and high-pressure gas inside the battery breaks through the explosion-proof valve, the high-temperature and high-pressure gas will be directly discharged into the battery pack case and run around in the battery pack case, causing impact on other normally operating batteries in the battery pack case and the electronic control components inside the battery pack case, causing damage. Therefore, traditional battery pack cases have poor protection and safety when thermal runaway occurs.

[0037] Therefore, in order to ensure protection and safety when thermal runaway occurs and reduce damage caused by thermal runaway, this embodiment provides a battery pack box, which is used to install multiple single cells.

[0038] like Figures 1 to 5 As shown, the battery pack case includes a lower case 1 and a protective end cover 2. The lower case 1 is provided with a receiving groove 11. The receiving groove 11 and the single battery located in the receiving groove 11 are filled with an insulating colloid for fixing the single battery. The protective end cover 2 corresponds to the receiving groove 11 one by one and closes the corresponding receiving groove 11. The insulating colloid seals the protective end cover 2 and the lower case 1. The failure temperature of the insulating colloid is lower than the thermal runaway temperature of the single battery. The protective end cover 2 is provided with a weakening structure 21. The thickness of the weakening structure 21 is less than the thickness of other parts of the protective end cover 2.

[0039] The protective end cover 2 and the lower box body 1 are sealed and connected by using an insulating colloid whose failure temperature is lower than the thermal runaway temperature of the single cell, and a weakening structure 21 with a thickness less than that of other parts of the protective end cover 2 is opened on the protective end cover 2. When thermal runaway occurs, due to the small thickness of the weakening structure 21, its structural strength is poor, so that the high-temperature and high-pressure gas is discharged to the outside by breaking through the weakening structure 21, and a pressure relief is performed once, thereby achieving a layer of protection. If the pressure relief requirement is still not met at this time, as the temperature gradually rises to the failure temperature of the insulating colloid, the insulating colloid melts, causing the bonding strength between the protective end cover 2 and the lower box body 1 to gradually decrease, until the bonding force is less than the pressure of the high-temperature and high-pressure gas, the high-temperature and high-pressure gas will further break through the protective end cover 2 and be discharged to the outside for a second pressure relief, thereby achieving double protection. The double pressure relief protection ensures the smooth discharge of high-temperature and high-pressure gas during thermal runaway, thereby improving the safety of the battery pack box.

[0040] The battery pack case can store various types of batteries. In this embodiment, it is primarily used to store large 12V cylindrical batteries. To ensure that the receiving slots 11 are compatible with the large cylindrical batteries, the cross-section of the receiving slots 11 is circular. The number of receiving slots 11 for storing single cells on the lower case 1 can be freely adjusted according to needs.

[0041] Alternatively, as Figure 3 、 Figure 4 As shown, the protective end cap 2 includes a sealing portion 22 and an inserting portion 23. The sealing portion 22 is bonded to the lower case 1 and is used to seal the receiving slot 11. The inserting portion 23 is inserted into the receiving slot 11 and abuts against the single battery. The sealing portion 22 and the inserting portion 23 constitute the protective end cap 2. On the one hand, it achieves a seal on the receiving slot 11. On the other hand, when the inserting portion 23 is inserted into the receiving slot 11 and abuts against the single battery, it can also limit and fix the single battery, preventing the single battery from shifting within the receiving slot 11. In this embodiment, since the cross-section of the receiving slot 11 is circular, the sealing portion 22 used to seal the receiving slot 11 is adapted thereto and also has a circular structure.

[0042] Alternatively, as Figure 4 As shown, the plug-in portion 23 includes an annular protrusion extending from the surface of the closure portion 22 in the direction toward the individual cells, forming a vent channel 24 inside the plug-in portion 23. The weakening structure 21 is located within the area of ​​the closure portion 22 enclosed by the vent channel 24. By forming the annular protrusion on the plug-in portion 23 extending from the surface of the closure portion 22 in the direction toward the individual cells, the vent channel 24 is formed inside the plug-in portion 23. Furthermore, the weakening structure 21 is provided within the area of ​​the closure portion 22 enclosed by the vent channel 24. This allows the vent channel 24 to guide high-temperature, high-pressure gas in the event of thermal runaway, allowing it to directly impact the weakening structure 21 of the closure portion 22, break through the weakening structure 21, and be discharged into the external environment. This prevents the high-temperature, high-pressure gas from roaming around within the battery pack and causing damage, thereby improving protection and safety during thermal runaway. In this embodiment, the explosion-proof valves for the individual cells are also contained within the area enclosed by the vent channel 24.

[0043] Alternatively, as Figure 3 、 Figure 4As shown, the protective end cover 2 is further provided with a limiting portion 25. The outer edge of the closing portion 22 extends in a direction away from the central axis to form the limiting portion 25. A limiting groove 12 is also provided on the surface of the lower case 1 where the closing portion 22 is bonded. The limiting portion 25 is accommodated in the limiting groove 12. By extending the outer edge of the closing portion 22 in a direction away from the central axis to form the limiting portion 25, when the protective end cover 2 is connected to the lower case 1, the limiting portion 25 and the limiting groove 12 provided on the lower case 1 are used to limit the protective end cover 2, thereby preventing the protective end cover 2 from shifting and affecting the sealing of the protective end cover 2 with the receiving groove 11.

[0044] Alternatively, as Figure 4 As shown, the protective end cap 2, which is composed of the closing portion 22, the plug portion 23, and the limit portion 25, is integrally formed by the injection molding process. By adopting the injection molding process to manufacture the protective end cap 2, the closing portion 22, the plug portion 23, and the limit portion 25 are conveniently formed at the same time, which reduces the number of processing steps and reduces the processing difficulty.

[0045] Alternatively, as Figure 4 As shown, a protective fillet 26 is provided at the corner of the limiting portion 25 on the side facing away from the closing portion 22. By providing the protective fillet 26 at the corner of the limiting portion 25 on the side facing away from the closing portion 22, the tip of the corner is prevented from damaging the limiting groove 12 when the limiting portion 25 is accommodated in the limiting groove 12, thereby affecting the sealing performance of the protective end cover 2 on the receiving groove 11.

[0046] Alternatively, as Figure 4 As shown, a plurality of limiting portions 25 are provided, and the plurality of limiting portions 25 are evenly distributed on the outer edge of the closing portion 22. By providing a plurality of limiting portions 25 on the outer edge of the closing portion 22, the limiting strength of the limiting portions 25 on the protective end cover 2 is enhanced, and the plurality of limiting portions 25 are evenly distributed, thereby ensuring that the force applied to each limiting portion 25 is uniform.

[0047] Alternatively, as Figure 4 、 Figure 5 As shown, the weakening structure 21 comprises an annular groove formed on the side of the protective end cap 2 facing the individual cells. By employing an annular groove as the weakening structure 21 formed on the sealing portion 22, the thickness of the sealing portion 22 is reduced, weakening the structural strength. This reduces the resistance of the sealing portion 22 to high-temperature, high-pressure gas during thermal runaway, allowing the gas to easily penetrate the weakening structure 21 on the sealing portion 22 and be discharged into the external environment. In this embodiment, the groove depth of the weakening structure 21 can be freely set according to design requirements.

[0048] Specifically, the cross-section of the annular groove is V-shaped or U-shaped. By adopting an annular groove with a V-shaped or U-shaped cross-section, the annular groove has a tendency to gather high-temperature and high-pressure gas at the bottom of the groove, so that the high-temperature and high-pressure gas is more concentrated after entering the annular groove, which is more conducive to breaking through the weakening structure 21 and being discharged into the external environment.

[0049] This embodiment also provides a battery pack comprising the aforementioned battery pack case. By utilizing the aforementioned battery pack case, the battery pack can promptly discharge the high-temperature, high-pressure gas generated by thermal runaway to the outside world in the event of thermal runaway, thereby preventing the thermal runaway from affecting other components within the battery pack case, minimizing the scope of damage, and reducing repair costs.

[0050] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A battery pack box, which is used to install multiple single batteries, characterized in that: The battery pack box includes: A lower box body (1), the lower box body (1) is provided with a receiving groove (11), and the receiving groove (11) and the single battery located in the receiving groove (11) are filled with an insulating colloid for fixing the single battery; A protective end cover (2) is provided, wherein the protective end cover (2) corresponds to the receiving groove (11) one by one and seals the corresponding receiving groove (11); the insulating colloid seals the protective end cover (2) and the lower box (1); the failure temperature of the insulating colloid is lower than the thermal runaway temperature of the single cell; the protective end cover (2) is provided with a weakening structure (21); the thickness of the weakening structure (21) is lower than the thickness of other parts of the protective end cover (2).

2. The battery pack case according to claim 1, characterized in that: The protective end cover (2) comprises a closing portion (22) and an inserting portion (23); the closing portion (22) is bonded to the lower box (1) and is used to close the receiving groove (11); and the inserting portion (23) is inserted into the receiving groove (11) and abuts against the single battery.

3. The battery pack case according to claim 2, characterized in that: The plug-in portion (23) includes an annular protrusion extending on the surface of the closing portion (22) in a direction close to the single battery, so as to form an exhaust channel (24) inside the plug-in portion (23), and the weakening structure (21) is provided in an area of ​​the closing portion (22) surrounded by the exhaust channel (24).

4. The battery pack case according to claim 2, characterized in that: The protective end cover (2) is further provided with a limiting portion (25), the outer edge of the closing portion (22) extends in a direction away from the central axis to form the limiting portion (25), and a limiting groove (12) is further provided on the surface where the lower box body (1) and the closing portion (22) are bonded, and the limiting portion (25) is accommodated in the limiting groove (12).

5. The battery pack case according to claim 4, characterized in that: The protective end cover (2) consisting of the closing portion (22), the plug-in portion (23) and the limiting portion (25) is integrally formed by an injection molding process.

6. The battery pack case according to claim 4, characterized in that: A protective fillet (26) is provided at the corner of the limiting portion (25) on the side facing away from the closing portion (22).

7. The battery pack case according to claim 4, characterized in that: There are a plurality of the limiting portions (25), and the plurality of limiting portions (25) are evenly distributed on the outer edge of the closing portion (22).

8. The battery pack case according to claim 1, characterized in that: The weakening structure (21) comprises an annular groove formed on a side of the protective end cover (2) facing the single battery.

9. The battery pack case according to claim 8, characterized in that: The cross section of the annular groove is V-shaped or U-shaped.

10. A battery pack, characterized in that: The battery pack includes the battery pack case according to any one of claims 1 to 9.

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