Battery pack and new energy vehicle

Abstract

The invention relates to a battery pack and a new energy vehicle. The battery pack comprises a box body, and a battery pack module, an insulating spacer and a liquid cooling plate are sequentially arranged in the box body; a flue and a liquid cooling flow channel are arranged in the liquid cooling plate; a first smoke outlet and a second smoke outlet which are communicated with the flue are respectively formed in the upper surface and the lower surface of the liquid cooling plate; after the explosion-proof valve is opened, gas in the battery cell enters the flue through the first smoke outlet and is discharged outwards along a pressure relief path at the bottom of the battery pack through the second smoke outlet; the pressure relief valve is ingenious in design, it is ensured that gas is effectively discharged in the pressure relief process, and accumulation of internal pressure is reduced; the flue and the liquid cooling flow channel are arranged in the liquid cooling plate at the same time, so that the liquid cooling plate has dual functions of pressure relief and heat dissipation, forced cooling can be performed through cooling liquid while the battery cell is subjected to pressure relief, coordination of thermal runaway suppression and thermal management is realized, and the service life of the battery cell is prolonged; and the battery pack module does not generate short circuit through the insulating sheet when the battery cell is in thermal runaway, so that the smoothness of the pressure relief channel and the electrical safety are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy batteries, and more specifically, to a battery pack and a new energy vehicle. Background Art

[0002] With the rapid development of new energy vehicles, the safety and thermal management performance of power battery packs have become key technical challenges. When the battery is overcharged, short-circuited or thermally out of control, a large amount of high-temperature gas and combustible substances will be generated. If they cannot be discharged in time, it may cause an explosion or a fire.

[0003] The utility model with patent number CN219457928U discloses a battery pack and a vehicle including the battery pack, which includes a bottom plate, a plurality of support plates and battery cells. The support plates are arranged on the bottom plate, the battery cells are arranged on the support plates, the support plates are located between the bottom plate and the battery cells, and the support plates have a certain height so that there is a certain height difference between the battery cells and the bottom plate. An exhaust hole is arranged on the bottom plate, and an explosion-proof valve is arranged at the exhaust hole. In the battery pack of this solution, the battery cells are supported by profile support plates, so that there is a certain height difference between the battery cells and the bottom plate. When the battery cells are thermally out of control, the high-temperature and high-pressure gas breaks through the explosion-proof valve and quickly discharges from the bottom exhaust hole to solve the problem that the hot air spreads in the battery pack during thermal runaway of the existing battery pack, resulting in danger. However, this solution still has the following problems:

[0004] 1. The battery cells rely only on the bottom exhaust hole for pressure relief and do not integrate a heat dissipation function. When thermally out of control, the high-temperature gas is directly discharged, and there is no active cooling mechanism during the exhaust process of the battery pack, which cannot suppress thermal spread or reduce the gas temperature, and there is a risk of secondary ignition.

[0005] 2. During the process of pressure relief and exhaust of the battery cells, the metal fragments of the explosion-proof valve may contact the side wall of the exhaust hole, resulting in a risk of short circuit and unsafe use. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a battery pack and a new energy vehicle in view of the above-mentioned defects of the prior art.

[0007] On the one hand, the technical solution adopted by the present invention to solve its technical problems is: a battery pack, including a box body, wherein a battery pack module and a liquid cooling plate are sequentially arranged in the box body from top to bottom; the battery pack module includes at least one battery cell; a pressure relief port and an explosion-proof valve are arranged at the bottom of the battery cell; a flue for cooperating with the explosion-proof valve to relieve the internal pressure of the battery pack module and a liquid cooling flow path for cooling the battery pack module are arranged in the liquid cooling plate; a first smoke exhaust port communicated with the flue and corresponding to the explosion-proof valve is arranged on the upper surface of the liquid cooling plate, and a second smoke exhaust port communicated with the flue is arranged on the lower surface; an insulating gasket for preventing the fragments when the explosion-proof valve opens from contacting the side wall of the first smoke exhaust port is further arranged between the battery pack module and the liquid cooling plate; after the explosion-proof valve opens, the gas in the battery cell enters the flue below through the first smoke exhaust port and is discharged outwards along the pressure relief path at the bottom of the battery pack through the second smoke exhaust port;

[0008] In the battery pack of the present invention, wherein a plurality of the flues are arranged at intervals, and the liquid cooling flow path sequentially winds around the plurality of flues;

[0009] In the battery pack of the present invention, wherein a plurality of the second smoke exhaust ports are arranged along the length of the flue; a plurality of fusible sheets corresponding to the flues one by one are arranged below the liquid cooling plate; the fusible sheets are used for covering all the second smoke exhaust ports corresponding to the flues;

[0010] In the battery pack of the present invention, wherein a plurality of the battery cells are arranged, and the plurality of battery cells are sequentially arranged along the length direction of the flue, and the explosion-proof valves of the plurality of battery cells are all within the coverage range of the flue; a plurality of the first smoke exhaust ports are arranged, and the plurality of explosion-proof valves correspond to the plurality of first smoke exhaust ports one by one;

[0011] In the battery pack of the present invention, wherein the explosion-proof valve includes at least one fragment covering the pressure relief port; the root of the fragment is fixedly connected with the battery cell, and the fragment can be folded towards the direction of the first smoke exhaust port with its root as the axis;

[0012] In the battery pack of the present invention, wherein a plurality of through holes communicated with the flue and for the plurality of fragments to fold through are arranged on the insulating gasket; the pressure relief port on the battery cell is communicated with the flue through the through hole;

[0013] In the battery pack of the present invention, wherein the area of the through hole is smaller than the area of the first smoke exhaust port;

[0014] In the battery pack of the present invention, wherein a battery drive module and a battery management module electrically connected to the battery drive module are further arranged on one side of the battery pack module in the box body; the battery drive module is electrically connected to the battery pack module;

[0015] For the battery pack of the present invention, a partition is fixedly installed inside the box body; the partition separates the battery module from the battery management module and the battery drive module;

[0016] On the other hand, the present aspect also provides a new energy vehicle, which includes a vehicle body; the above-mentioned battery pack as described in any one of the above is provided on the vehicle body.

[0017] The beneficial effects of the present invention are as follows: The battery pack with bottom exhaust and the new energy vehicle are ingeniously designed. When a thermal runaway occurs in the battery cell, the gas inside the battery cell can enter the flue through the first smoke exhaust port and be discharged from the pressure relief port, ensuring the effective discharge of gas during the pressure relief process and reducing the accumulation of internal pressure; by simultaneously arranging a flue and a liquid cooling flow channel in the liquid cooling plate, the liquid cooling plate has the dual functions of pressure relief and heat dissipation. When the battery cell relieves pressure, it can be forced to cool down by the coolant at the same time, realizing the coordination of thermal runaway suppression and thermal management and prolonging the service life of the battery cell; by arranging an insulating gasket between the battery module and the liquid cooling plate and using physical isolation to prevent the fragments from contacting the side wall of the smoke exhaust port, no short circuit will occur when a thermal runaway occurs in the battery cell, ensuring the smoothness of the pressure relief channel and electrical safety, and thus significantly improving the safety and environmental adaptability of the battery pack, which is applicable to high energy density scenarios. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will further explain the present invention in conjunction with the drawings and embodiments. The drawings in the following description are only partial embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts:

[0019] Figure 1 It is a schematic structural diagram of a battery pack in Embodiment 1 of the present invention;

[0020] Figure 2 is Figure 1 the three-dimensional exploded view of the battery pack in

[0021] Figure 3 is Figure 1 the sectional view at A-A in

[0022] Figure 4 is Figure 3 the enlarged view at D in

[0023] Figure 5 It is the internal partial structure of the battery pack in Embodiment 1 Figure 1 (state where the fragment is not folded).

[0024] Figure 6 It is the internal partial structure of the battery pack in Embodiment 1 Figure 2(Fragment folding state).

[0025] Figure 7 is Figure 1 An exploded perspective view of the liquid cooling plate 13 in it. Specific embodiments

[0026] The terms "first", "second", "third", "fourth", etc. in the description and claims of the present invention and the accompanying drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0027] Referring to "embodiment" herein means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0028] "Plurality" means two or more. "And / or" describes the association relationship of associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0029] Moreover, the orientation terms "upper, lower, front, rear, left, right, upper end, lower end, longitudinal", etc. are all referenced based on the attitude position of the device or equipment described in this solution when it is in normal use.

[0030] In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are partial embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] 1. Embodiment 1:

[0032] A battery pack according to a preferred embodiment of the present invention, as Figure 1-7As shown in the figure, it includes a box body 11, and a battery pack module 12 and a liquid cooling plate 13 are successively arranged in the box body 11 from top to bottom; the battery pack module 12 includes at least one battery cell 121; a pressure relief port 122 and an explosion-proof valve are arranged at the bottom of the battery cell 121, and when the internal pressure of the battery cell 121 rises abnormally, the pressure can be quickly released outward through the explosion-proof valve; a flue 131 for cooperating with the explosion-proof valve to relieve the internal pressure of the battery pack module 12 and a liquid cooling flow channel 132 for cooling the battery pack module 12 are arranged in the liquid cooling plate 13; a first smoke exhaust port 133 communicated with the flue 131 and corresponding to the explosion-proof valve is arranged on the upper surface of the liquid cooling plate 13, and a second smoke exhaust port 134 communicated with the flue 131 is arranged on the lower surface; an insulating gasket 14 for preventing the fragment 123 when the explosion-proof valve opens from contacting the side wall of the first smoke exhaust port 133 is further arranged between the battery pack module 12 and the liquid cooling plate 13, so as to prevent short circuit when the battery cell relieves pressure, and further improve the safety performance of the battery pack; after the explosion-proof valve opens, the gas in the battery cell 121 enters the lower flue 131 through the first smoke exhaust port 133 and is discharged outward along the pressure relief path at the bottom of the battery pack through the second smoke exhaust port 134; when the battery has a thermal runaway, the above structure can respond quickly, and quickly discharge heat and gas through the explosion-proof valve, the flue on the liquid cooling plate 13 and the pressure relief path, reducing the risk brought by the thermal runaway.

[0033] The battery pack with bottom exhaust and the new energy vehicle are ingeniously designed. When the battery cell has a thermal runaway, the gas in the battery cell can enter the flue through the first smoke exhaust port and be discharged from the pressure relief port, ensuring the effective discharge of gas during the pressure relief process and reducing the accumulation of internal pressure; by simultaneously arranging a flue and a liquid cooling flow channel in the liquid cooling plate, the liquid cooling plate has the dual functions of pressure relief and heat dissipation. When the battery cell relieves pressure, it can be forced to cool down by the coolant at the same time, realizing the coordination of thermal runaway suppression and thermal management and prolonging the service life of the battery cell; by arranging an insulating gasket between the battery pack module and the liquid cooling plate, the fragment is physically isolated from contacting the side wall of the smoke exhaust port, and no short circuit will occur when the battery cell has a thermal runaway, ensuring the smoothness of the pressure relief channel and electrical safety, and thus significantly improving the safety and environmental adaptability of the battery pack, and being applicable to high energy density scenarios.

[0034] Further, a plurality of flues 131 are arranged at intervals, and the liquid cooling flow channel 132 successively winds around the plurality of flues 131. The plurality of flues can quickly discharge the internal high-pressure gas of a plurality of battery cells, reduce the internal pressure, and prevent battery explosion or fire accidents; the area of the liquid cooling flow channel is large, which can not only cool the battery cell, but also cool the high-temperature gas pressure in the flue. Optionally, the liquid cooling flow channel is serpentine; in one embodiment, the head and tail of the liquid cooling flow channel are connected to form a reflux cooling channel, making the heat distribution more uniform and avoiding local overheating; optionally, an inlet and outlet 135 communicated with the liquid cooling plate body is further arranged on the liquid cooling plate body.

[0035] In one embodiment, asFigure 7 As shown in Figure 7 , the liquid cooling plate body 13 includes a liquid cooling flow channel plate 1301 and a liquid cooling flat plate 1302 fixedly connected to the liquid cooling flow channel plate 1301; the liquid cooling flat plate 1302 and the liquid cooling flow channel plate 1301 are arranged one above the other; the liquid cooling flow channel plate 1301 is responsible for forming the flow path of the coolant, and the liquid cooling flat plate 1302 serves as the main surface for heat exchange with the battery pack; the flue 131 and the liquid cooling flow channel 132 are both integrally arranged on the liquid cooling flow channel plate 1301. In this embodiment, the liquid cooling flow channel plate and the liquid cooling flat plate are closely attached, and heat can be more directly transferred from the liquid cooling flat plate to the liquid cooling flow channel and then taken away by the coolant, improving the heat conduction efficiency. The first smoke exhaust port 133 is arranged on the liquid cooling flat plate 1302; the second smoke exhaust port 134 is arranged on the liquid cooling flow channel plate 1301.

[0036] Furthermore, a plurality of second smoke exhaust ports 134 are arranged along the length of the flue 131; a plurality of fusible sheets 15 corresponding to the flue 131 one by one are arranged below the liquid cooling plate 13; the fusible sheet 15 can be a fusible material such as a film or a thin sheet in the prior art. The fusible sheet 15 is used to cover all the second smoke exhaust ports 134 of the corresponding flue 131. The fusible sheet 15 usually remains closed to prevent external gas of the battery from entering; for example, when the battery pack has a thermal runaway, the gas ejected outward has a temperature of about 300 °C or above, which melts or softens the fusible sheet 15, so that the second smoke exhaust port 134 is opened, and the gas is discharged outward along the lower pressure relief path.

[0037] Furthermore, a plurality of battery cells 121 are provided, and adjacent two battery cells 121 are electrically connected by electrode plates; the plurality of battery cells 121 are arranged in sequence along the length direction of the flue 131, and the explosion-proof valves of the plurality of battery cells 121 are all within the coverage range of the flue 131; a plurality of first smoke exhaust ports 133 are arranged, and the plurality of explosion-proof valves correspond to the plurality of first smoke exhaust ports 133; the structure is compact and the volume is small.

[0038] Furthermore, as Figure 5-6 , the explosion-proof valve includes at least one fragment 123 covering the pressure relief port 122; the root of the fragment 123 is fixedly connected to the battery cell 121, and the fragment 123 can be folded towards the first smoke exhaust port 133 with its root as the axis, with a fast response. Once the pressure exceeds the set value, the fragment can act immediately, effectively preventing the battery from exploding due to excessive internal pressure. In one embodiment, a plurality of fragments 123 can be provided; the fragments 123 extend from the edge of the pressure relief port 122 towards the middle of the pressure relief port 122; the plurality of fragments can disperse the impact force during pressure relief, reduce the stress borne by a single fragment, and reduce the risk of fragment damage. The plurality of fragments can also quickly fold outward, and the pressure relief is faster; alternatively, the fragment 123 can also be provided as one, the root of the fragment 123 is fixedly connected to the battery cell, and the other end can be separated from the battery cell. When the battery cell has high heat, the other end of the fragment 123 folds outward under the influence of high pressure.

[0039] Furthermore, a plurality of through holes 141 communicating with the flue 131 and allowing a plurality of fragments 123 to fold and pass through are provided on the insulating gasket 14; the pressure relief port 122 on the battery cell 121 is connected to the flue 131 through the through holes 141. As Figure 6 shown, when the fragment 123 is folded in place, the free end of the fragment 123 passes through the through hole 141 and extends into the first smoke exhaust port 133. At this time, the fragment 123 does not contact the side wall of the first smoke exhaust port 133, effectively avoiding short circuit. Furthermore, when the fragment 123 is folded in place, the end of the fragment 123 connected to the battery cell abuts against the inner side wall of the through hole 141 or presses the edge of the through hole 141 to make it concave towards the smoke exhaust port 121.

[0040] Optionally, the insulating gasket 14 is made of a deformable soft material, such as a foam sheet, etc.; furthermore, the soft material also has heat resistance properties, such as silicone, which is both a soft material and has heat resistance; for example, it can maintain stable physical properties in the range of 0°C to 600°C. When the battery cell generates high heat, the insulating sheet will not melt, effectively preventing the fragment from contacting the side wall of the first smoke exhaust port; furthermore, the insulating gasket 14 can also fill the gap between the liquid cooling plate and the battery pack module 12, leaving a buffer gap between the liquid cooling plate and the battery pack module 12, maintaining the structural stability of the entire battery pack.

[0041] Furthermore, the area of the through hole 141 is smaller than the area of the first smoke exhaust port 133. Optionally, the center line of the through hole 141 coincides with the center line of the first smoke exhaust port, which can ensure that the fragment will not contact the side wall of the first smoke exhaust port due to excessive folding during folding, thus avoiding the risk of short circuit and being safer to use.

[0042] In one embodiment, a battery management module 16 and a battery drive module 17 are further provided on one side of the battery pack module 12 in the box 11. Among them, one side of the battery drive module 17 is electrically connected to the battery management module 16, and the other side is electrically connected to the battery pack module 12. Through the battery management module (BMS), the charge and discharge status of the battery pack module can be monitored and adjusted to ensure that the battery operates under the best working conditions and improve the energy utilization efficiency. The battery drive module 17 (BDU) is usually responsible for converting the electrical energy of the battery pack into an electrical energy form suitable for vehicle use and interfacing with the vehicle's drive system. Integrated with the BMS, more efficient power management can be achieved.

[0043] Furthermore, a partition 18 is fixedly installed inside the box body 11; the partition 18 separates the battery pack module 12 from the battery management module 16 and the battery drive module 17, thereby isolating the electromagnetic interference between the battery pack module and the electronic components (the battery management module 16 and the battery drive module 17), ensuring the stable operation of the electronic components of the battery management module and the battery drive module; and the partition can also prevent the battery pack module from damaging the electronic module in extreme cases (such as short circuit and thermal runaway), thereby improving the safety of the entire battery pack.

[0044] 2. Embodiment 2:

[0045] The present invention provides a new energy vehicle, which includes a vehicle body; a battery pack as described in Embodiment 1 is provided on the vehicle body.

[0046] The design of this new energy vehicle is ingenious. When a thermal runaway occurs in the battery cell, the gas inside the battery cell can enter the flue through the first smoke exhaust port and be discharged from the pressure relief port, ensuring the effective discharge of gas during the pressure relief process and reducing the accumulation of internal pressure; by simultaneously arranging a flue and a liquid cooling channel in the liquid cooling plate, the liquid cooling plate has the dual functions of pressure relief and heat dissipation. When the battery cell is under pressure relief, it can be forced to cool down through the coolant, realizing the coordination of thermal runaway suppression and thermal management, and extending the service life of the battery cell; by setting an insulating gasket between the battery pack module and the liquid cooling plate, the fragment is physically isolated from the side wall of the smoke exhaust port, and no short circuit will occur when a thermal runaway occurs in the battery cell, ensuring the smoothness of the pressure relief channel and electrical safety, and thus significantly improving the safety and environmental adaptability of the battery pack, and being applicable to high energy density scenarios.

[0047] It should be understood that those of ordinary skill in the art can make improvements or changes according to the above description, and all such improvements and changes should fall within the protection scope of the appended claims of the present invention.

Claims

1. A battery pack, comprising a box, characterized in that: A battery pack module and a liquid cooling plate are sequentially arranged in the box from top to bottom; the battery pack module includes at least one battery cell; a pressure relief port and an explosion-proof valve are arranged at the bottom of the battery cell; a flue is arranged in the liquid cooling plate for cooperating with the explosion-proof valve to relieve the internal pressure of the battery pack module, and a liquid cooling flow channel for dissipating heat from the battery pack module; a first smoke exhaust port connected to the flue and corresponding to the explosion-proof valve is arranged on the upper surface of the liquid cooling plate, and a second smoke exhaust port connected to the flue is arranged on the lower surface; an insulating gasket is also arranged between the battery pack module and the liquid cooling plate to prevent the fragments of the explosion-proof valve from contacting the side wall of the first smoke exhaust port when the explosion-proof valve is opened; after the explosion-proof valve is opened, the gas in the battery cell enters the flue below through the first smoke exhaust port and is discharged outwardly through the second smoke exhaust port along the pressure relief path at the bottom of the battery pack.

2. The battery pack according to claim 1, characterized in that: A plurality of flues are arranged at intervals, and the liquid cooling channel passes through the plurality of flues in sequence.

3. The battery pack according to claim 2, characterized in that: A plurality of the second smoke exhaust ports are arranged along the length of the flue; a plurality of fusible sheets corresponding to the flue are arranged below the liquid cooling plate; the fusible sheets are used to cover all the second smoke exhaust ports corresponding to the flue.

4. The battery pack according to claim 1, characterized in that: There are multiple battery cells, which are arranged in sequence along the length direction of the flue, and the explosion-proof valves of the multiple battery cells are all within the coverage range of the flue; there are multiple first smoke exhaust ports, and the multiple explosion-proof valves correspond one-to-one to the multiple first smoke exhaust ports.

5. The battery pack according to any one of claims 1 to 4, characterized in that: The explosion-proof valve includes at least one broken piece covering the pressure relief port; the root of the broken piece is fixedly connected to the battery core, and the broken piece can be folded toward the first smoke exhaust port with its root as the axis.

6. The battery pack according to claim 5, characterized in that: The insulating gasket is provided with a plurality of through holes which are connected with the flue and through which the plurality of broken pieces can be folded and passed; the pressure relief port on the battery core is connected with the flue through the through holes.

7. The bottom vented battery pack according to claim 6, characterized in that: The area of ​​the through hole is smaller than the area of ​​the first smoke exhaust port.

8. The bottom vented battery pack according to claim 1, characterized in that: A battery driving module and a battery management module electrically connected to the battery driving module are also provided in the box at one side of the battery pack module; the battery driving module is electrically connected to the battery pack module.

9. The bottom-scheduled battery pack according to claim 8, characterized in that: A partition is also fixedly installed in the box; the partition separates the battery pack module from the battery management module and the battery driving module.

10. A new energy vehicle, characterized in that: It comprises a vehicle body; the vehicle body is provided with a battery pack as described in any one of claims 1-9.

Images