A battery pack

Abstract

The application discloses a battery pack, which belongs to the technical field of batteries and comprises a battery box, a battery module and heat-conducting structural glue. The battery module is located in the battery box. The battery module comprises at least two rows of battery rows and insulating plates. The at least two rows of battery rows are arranged side by side along an X direction. The insulating plates are respectively arranged on both sides of the battery rows along a Y direction. One insulating plate is shared by the same end of the at least two rows of battery rows arranged side by side. A first channel is surrounded by the junction of the two adjacent rows of battery rows and the insulating plate. The side of the insulating plate along the Y direction towards the battery row is provided with a second channel. The fluid inlet of the second channel is located on the side of the insulating plate along a Z direction close to the bottom surface of the battery box. The first channel is in communication with the fluid inlet. The heat-conducting structural glue is arranged between the battery module and the bottom surface of the battery box. When the battery module is assembled into the battery box, the gas in the heat-conducting structural glue can be discharged through the first channel and the second channel, and the overflowed heat-conducting structural glue can be accommodated.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery pack. Background Technology

[0002] Most battery packs adopt the CTP (Cell-to-Pack) solution, which involves stacking the cells and placing them directly into the battery pack. During the battery pack production process, the battery modules are fixed to the battery box with thermally conductive structural adhesive, and the cells are pre-fixed to the heat insulation material with double-sided adhesive. Therefore, the overall structural strength of the battery modules is relatively weak, and they are prone to vibration failure.

[0003] In related technologies, thermally conductive structural adhesive is applied to the bottom of the battery module or inside the mounting cavity of the battery housing, and a clamping device is used to hold the battery module in the mounting cavity. During the battery module insertion process, the battery module is first squeezed to a size smaller than the mounting cavity. After the battery module enters 1 / 3 to 1 / 2 of the mounting cavity, the clamping device is released, and the battery module is pressed in from top to bottom. Due to the large adhesive application area at the bottom of the battery module, coupled with the influence of the cold plate flatness, air exists between the bottom of the battery module and the adhesive interface during the pressing process. This air moves towards both ends as the adhesive spreads and flows during the pressing process, eventually settling at the end of the battery module near the frame beam of the battery housing. At the same time, a sealed space is formed between the bottom of the battery module and the mounting cavity. When the battery module is pressed open, air bubbles are formed in the adhesive, and the internal gas cannot escape, forming cavitation areas. The presence of numerous air bubbles not only reduces the adhesion strength between the thermally conductive structural adhesive and the battery housing but also increases the thermal resistance between the end cells and the cold plate, affecting thermal management performance. Summary of the Invention

[0004] The purpose of this invention is to provide a battery pack that solves the technical problem in the prior art where gas cannot be discharged during the cell module loading process, resulting in the formation of cavitation areas in the thermally conductive structural adhesive.

[0005] Based on the above concept, the technical solution adopted by this invention is as follows:

[0006] A battery pack, comprising:

[0007] Battery housing;

[0008] A battery module, located inside the battery housing, comprises:

[0009] The battery bank comprises at least two rows of battery bars and an insulating plate. The at least two rows of battery bars are arranged side-by-side along the X direction. The insulating plates are respectively disposed on both sides of the battery bars along the Y direction. The at least two rows of battery bars share a common insulating plate at the same end. A first channel is formed between the junction of two adjacent rows of battery bars and the insulating plate. A second channel is provided on the side of the insulating plate along the Y direction facing the battery bars. The fluid inlet of the second channel is located on the side of the insulating plate along the Z direction near the bottom surface of the battery housing. The first channel communicates with the fluid inlet.

[0010] Thermally conductive structural adhesive is applied between the bottom surface of the battery module and the battery housing to bond and fix the two together.

[0011] When the battery module is assembled into the battery housing, the gas in the thermally conductive structural adhesive can be discharged and the overflowing thermally conductive structural adhesive can be contained through the first channel and the second channel.

[0012] The X direction is the width direction of the battery module, the Y direction is the length direction of the battery module, and the Z direction is the height direction of the battery module.

[0013] Preferably, the fluid inlet extends along the X direction on the insulating plate and penetrates to at least one end of the insulating plate along the X direction.

[0014] Preferably, the second channel extends along the Z direction, and the height of the fluid inlet along the Z direction gradually increases on both sides of the second channel along the X direction away from the second channel.

[0015] Preferably, each row of battery packs is provided with a second channel, and the second channel is located at the middle position of the battery pack along the X direction.

[0016] Preferably, the battery module includes two rows of battery packs, the first channel is located between the two second channels, and the height of the fluid inlet along the Z direction gradually increases from the second channel to the first channel.

[0017] Preferably, each row of battery packs is provided with end heat insulation pads on both sides along the Y direction, and the end heat insulation pads are provided on the side of the insulating plate close to the battery pack;

[0018] The end heat insulation pad is spaced apart from the bottom surface of the battery box along the Z direction to avoid at least part of the fluid inlet, and the end heat insulation pads of two adjacent rows of battery bars are spaced apart to avoid the first channel.

[0019] Preferably, the battery pack includes multiple battery cells arranged along the Y direction, and a thermal protection structure is provided between each pair of adjacent battery cells. The thermal protection structure has a receiving groove on one side along the Z direction near the bottom surface of the battery box to receive the thermally conductive adhesive.

[0020] Preferably, the thermal protection structure includes a phase change material layer and a heat insulation material layer that are bonded together, wherein the phase change material layer is on one side of the battery cell along the Y direction, and the heat insulation material layer is on the other side of the battery cell along the Y direction.

[0021] Preferably, a buffer frame is provided around the outer periphery of the heat insulation material layer, and the buffer frame is open on one side of the bottom surface of the battery box along the Z direction to form the receiving groove.

[0022] Preferably, the phase change material layer includes an aluminum-plastic film shell and a phase change heat insulation material disposed within the aluminum-plastic film shell. At least a portion of the phase change material layer is stacked with a thermally conductive layer, which is attached to the battery cell. The thermally conductive layer has a receiving groove on one side along the Z direction near the bottom surface of the battery housing.

[0023] The beneficial effects of this invention are:

[0024] The battery pack proposed in this invention has a battery module located inside the battery box. The battery module includes at least two rows of battery bars and an insulating plate. The at least two rows of battery bars are arranged side by side along the X direction, and the insulating plates are respectively disposed on both sides of the battery bars along the Y direction. The same end of the at least two rows of battery bars arranged side by side shares a single insulating plate to reduce the number of insulating plates and increase structural strength. The junction of two adjacent rows of battery packs and the insulating plate form a first channel. A second channel is provided on the side of the insulating plate facing the battery pack along the Y direction. The fluid inlet of the second channel is located on the side of the insulating plate along the Z direction near the bottom surface of the battery box. The first channel is connected to the fluid inlet, making full use of the gap between the two adjacent rows of battery packs. Thermally conductive structural adhesive is placed between the bottom surface of the battery module and the battery box to bond and fix the two together. When the battery module is installed into the battery box, the gas in the thermally conductive structural adhesive can be discharged through the first and second channels, and the overflowing thermally conductive structural adhesive can be contained. This avoids the formation of air bubble cavities between the battery module and the battery box, improves the bonding strength between the thermally conductive structural adhesive and the battery box, and ensures the continuity of the heat conduction path within the battery pack, thereby improving the heat conduction efficiency. Attached Figure Description

[0025] Figure 1 This is a first schematic diagram of a portion of the battery pack structure provided in an embodiment of the present invention;

[0026] Figure 2This is a second schematic diagram of a portion of the battery pack structure provided in an embodiment of the present invention;

[0027] Figure 3 This is a third schematic diagram of a portion of the battery pack structure provided in an embodiment of the present invention;

[0028] Figure 4 yes Figure 3 Enlarged view of point A;

[0029] Figure 5 This is a partial exploded view of the battery pack structure provided in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the insulating plate provided in an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of the cooperation between the insulating plate and the end heat insulation pad provided in an embodiment of the present invention;

[0032] Figure 8 This is a partial structural side view of the battery pack provided in an embodiment of the present invention;

[0033] Figure 9 yes Figure 8 Enlarged view of point B;

[0034] Figure 10 This is a schematic diagram of the battery pack structure provided in an embodiment of the present invention;

[0035] Figure 11 This is a first structural schematic diagram of the thermal protection structure provided in an embodiment of the present invention;

[0036] Figure 12 This is a schematic diagram of the second structure of the thermal protection structure provided in an embodiment of the present invention;

[0037] Figure 13 This is an exploded structural diagram of the thermal protection structure provided in an embodiment of the present invention.

[0038] In the picture:

[0039] 100. Battery module;

[0040] 10. Battery pack; 101. First channel; 11. Battery cell; 12. Thermal protection structure; 121. Receptacle; 122. Phase change material layer; 123. Thermal insulation material layer; 124. Buffer frame; 125. Thermal conductive layer;

[0041] 20. Insulating plate; 21. Second channel; 211. Fluid inlet; 212. Fluid outlet;

[0042] 30. End heat insulation pad;

[0043] 200, thermally conductive structural adhesive; 300, central water-cooled plate; 400, bottom water-cooled plate. Detailed Implementation

[0044] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0045] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0047] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0048] See Figures 1 to 13 This embodiment provides a battery pack, including a battery housing, a battery module 100, and a thermally conductive structural adhesive 200. The battery module 100 is located inside the battery housing, and the thermally conductive structural adhesive 200 is disposed between the battery module 100 and the bottom surface of the battery housing to bond and fix the two together. Specifically, the battery housing has a mounting cavity, the thermally conductive structural adhesive 200 is disposed on the bottom wall of the mounting cavity, and the battery module 100 is disposed inside the mounting cavity.

[0049] The battery module 100 includes at least two rows of battery bars 10 and insulating plates 20. The at least two rows of battery bars 10 are arranged side by side along the X direction, and the insulating plates 20 are respectively disposed on both sides of the battery bars 10 along the Y direction. In this embodiment, the X direction is the width direction of the battery module 100, the Y direction is the length direction of the battery module 100, and correspondingly, the Z direction is the height direction of the battery module 100. Figure 1 and Figure 2 The arrows in the middle indicate the X, Y, and Z directions.

[0050] At least two rows of battery banks 10 arranged side-by-side share an insulating plate 20 at the same end to reduce the number of insulating plates 20 and increase structural strength. The junction of two adjacent rows of battery banks 10 and the insulating plate 20 form a first channel 101, as shown below. Figure 4 As shown, the gap between two adjacent rows of battery packs 10 is fully utilized. A second channel 21 is provided on the side of the insulating plate 20 facing the battery pack 10 along the Y direction, as shown... Figure 2 and Figure 6 As shown, the fluid inlet 211 of the second channel 21 is located on the side of the insulating plate 20 along the Z direction near the bottom surface of the battery box, and the first channel 101 is connected to the fluid inlet 211.

[0051] When the battery module 100 is installed into the battery housing, a sealed space is formed between the bottom of the battery module 100 and the battery housing. When the thermally conductive structural adhesive 200 is squeezed, the gas inside the battery module 100 is difficult to expel. By setting the first channel 101 and the second channel 21, the gas inside the thermally conductive structural adhesive 200 can be discharged and the overflowing thermally conductive structural adhesive 200 can be contained. This avoids the formation of air bubble cavities between the battery module 100 and the battery housing, improves the bonding strength between the thermally conductive structural adhesive 200 and the battery housing, and at the same time ensures the continuity of the heat conduction path inside the battery pack, thereby improving the heat conduction efficiency.

[0052] The number of battery rows 10 can be set according to actual needs. In some embodiments, the battery module 100 includes two rows of battery rows 10, which are arranged side by side along the X direction. Insulating plates 20 are respectively disposed on both sides of the battery rows 10 along the Y direction. There are two insulating plates 20, and the same end of the two rows of battery rows 10 shares one insulating plate 20. In some embodiments, the battery module 100 includes three rows of battery rows 10, which are arranged side by side along the X direction. Insulating plates 20 are respectively disposed on both sides of the battery rows 10 along the Y direction. There are two insulating plates 20, and the same end of the three rows of battery rows 10 shares one insulating plate 20. In some embodiments, the battery module 100 includes four rows of battery rows 10, which are arranged side by side along the X direction. Insulating plates 20 are respectively disposed on both sides of the battery rows 10 along the Y direction. There are four insulating plates 20, and the same end of every two rows of battery rows 10 shares one insulating plate 20.

[0053] The battery pack 10 includes multiple battery cells 11, which are arranged along the Y direction. For example... Figure 4 As shown, the corners of the casing of the battery cell 11 are usually rounded, so a gap is formed between the junction of two adjacent rows of battery packs 10 and the insulating plate 20. This gap is used as the first channel 101 to make full use of the existing structure for venting and glue overflow without affecting the structural strength of the insulating plate 20, thereby reducing costs.

[0054] Understandably, the first channel 101 extends in a straight line along the Z direction, with its bottom connected to the fluid inlet 211 and its top used for fluid discharge. When the thermally conductive structural adhesive 200 enters the first channel 101, it can bond adjacent battery packs 10 and insulating plates 20, making the connection stronger.

[0055] The number of second channels 21 provided on the insulating board 20 can be set according to actual needs. While ensuring air venting and adhesive overflow, the structural strength of the insulating board 20 should also be taken into account. Therefore, the number of second channels 21 should not be too large. The cross-sectional shape of the second channel 21 can be U-shaped, V-shaped, trapezoidal, semi-circular, or rectangular.

[0056] The fluid inlet 211 of the second channel 21 is located on the side of the insulating plate 20 along the Z direction near the bottom surface of the battery housing, so that the thermally conductive structural adhesive 200 between the bottom of the battery module 100 and the battery housing can enter the fluid inlet 211. One or more fluid inlets 211 can be provided. Exemplarily, the fluid inlet 211 extends along the X direction on the insulating plate 20 and penetrates to at least one end of the insulating plate 20 along the X direction. By having the fluid inlet 211 penetrate at least one end of the insulating plate 20 along the X direction, gas and adhesive can be discharged from the end of the insulating plate 20 along the X direction. The thermally conductive structural adhesive 200 overflowing from the end in the X direction can bond adjacent insulating plates 20 together, enhancing structural strength.

[0057] For example, the fluid inlet 211 extends along the X direction on the insulating plate 20 and penetrates to both ends of the insulating plate 20 along the X direction. The thermally conductive structural adhesive 200 between the bottom of the battery module 100 and the battery housing can enter through the fluid inlet 211 and exit from both ends of the insulating plate 20 along the X direction, and part of the thermally conductive structural adhesive 200 can enter the second channel 21 through the fluid inlet 211.

[0058] The second channel 21 has a fluid outlet 212, through which fluid can enter the second channel 21 from the fluid inlet 211 and flow along the second channel 21 to the fluid outlet 212. The fluid can be a gas or a colloid of the thermally conductive structural adhesive 200, which can flow in a liquid state before solidification.

[0059] The fluid outlet 212 can be located on the side of the insulating plate 20 away from the bottom surface of the battery box along the Z direction, or the fluid outlet 212 can be located on both sides of the insulating plate 20 along the X direction. Each second channel 21 can have one fluid outlet 212, or it can have two or more fluid outlets 212.

[0060] The second channel 21 can extend in a straight line, allowing for smoother airflow, lower airflow resistance, and easier rapid exhaust. In other embodiments, the second channel 21 can extend diagonally or curvedly to lengthen its path and accommodate more overflowing thermally conductive structural adhesive 200.

[0061] In this embodiment, the second channel 21 extends along the Z direction, as shown below. Figure 6 As shown, the second channel 21 extends in a straight line along the Z direction, and the fluid outlet 212 of the second channel 21 is located on the side of the insulating plate 20 away from the bottom surface of the battery box along the Z direction. By setting the second channel 21, combined with the fluid inlet 211 penetrating through the insulating plate 20 along the X direction to both ends of the insulating plate 20, it is possible to vent air and allow adhesive to overflow from both the top and both ends of the insulating plate 20.

[0062] Along the X-direction of the second channel 21, the height of the fluid inlet 211 gradually increases in the Z-direction, moving away from the second channel 21. When the battery module 100 is installed into the battery housing, the battery module 100 compresses the thermally conductive structural adhesive 200, causing the adhesive to flow to both sides. Therefore, the height of the fluid inlet 211 facilitates adhesive removal. In other embodiments, the height of the fluid inlet 211 along the Z-direction is uniform along the X-direction of the insulating plate 20, which is convenient for manufacturing.

[0063] For each row of battery packs 10, one or more second channels 21 can be provided. For example, one second channel 21 is provided for each row of battery packs 10, and the second channel 21 is located at the middle position of the battery pack 10 along the X direction. When the battery module 100 is installed into the battery housing, the battery module 100 compresses the thermally conductive structural adhesive 200, pushing the thermally conductive structural adhesive 200 in the middle area of ​​the battery module 100 to both sides. By positioning the second channel 21 at the middle position of the battery pack 10 along the X direction, it can maximize the exhaust of gas from both ends of the battery module 100 along the Y direction, while also accommodating the outflow of the thermally conductive structural adhesive 200. This solves the problem of a long exhaust path caused by the long length of the battery module 100.

[0064] For example, the battery module 100 includes two rows of battery bars 10, with a common insulating plate 20 at the same end of the two rows of battery bars 10. A first channel 101 is located between two second channels 21, and the height of the fluid inlet 211 along the Z-direction gradually increases from the second channel 21 to the first channel 101. The gradual increase in height of the fluid inlet 211 along the Z-direction from the second channel 21 to the first channel 101 facilitates the flow of the thermally conductive structural adhesive 200 from the middle region of the battery module 100 to both sides, preventing the accumulation of the thermally conductive structural adhesive 200 in the middle region.

[0065] With the cooperation of the fluid inlet 211, the first channel 101 and the second channel 21, when the battery module 100 is installed into the battery box, the thermally conductive structural adhesive 200 flows along the fluid inlet 211. Part of the thermally conductive structural adhesive 200 enters the first channel 101 and part of the thermally conductive structural adhesive 200 enters the second channel 21. This solves the problem of cavitation areas easily forming inside the thermally conductive structural adhesive 200, improves the bonding strength between the thermally conductive structural adhesive 200 and the battery box, and ensures the continuity of the heat conduction path inside the battery pack, thereby improving the heat transfer efficiency.

[0066] To further improve heat transfer efficiency, each row of battery packs 10 is equipped with end heat insulation pads 30 on both sides along the Y direction, as detailed below. Figure 4 and Figure 5 The end heat insulation pad 30 is disposed on the side of the insulating plate 20 near the battery pack 10. The end heat insulation pad 30 is used to block heat transfer, prevent thermal runaway, and play a role in mechanical buffering and electrical insulation.

[0067] See Figures 7 to 9 The end heat insulation pad 30 is spaced apart from the bottom surface of the battery box along the Z direction to avoid at least part of the fluid inlet 211. The end heat insulation pads 30 of adjacent rows of battery packs 10 are also spaced apart to avoid the first channel 101. While providing heat insulation, the end heat insulation pad 30 avoids the flow path of gas and colloid, and does not affect the venting and overflow of fluid inlet 211 and first channel 101. When the battery module 100 is installed into the battery box, the battery module 100 squeezes the thermally conductive structural adhesive 200 to flow into the fluid inlet 211. The thermally conductive structural adhesive 200 fills the bottom of the end heat insulation pad 30, and part of the thermally conductive structural adhesive 200 enters the first channel 101 and the second channel 21, improving the bonding strength of the end heat insulation pad 30, the insulating plate 20, the battery module 100, and the battery box.

[0068] See Figures 1 to 5 A central water-cooling plate 300 is provided between two adjacent rows of battery packs 10, and a bottom water-cooling plate 400 is provided at the bottom of the battery pack 10. The central water-cooling plate 300 and the bottom water-cooling plate 400 work together to dissipate heat from the battery pack 10, prevent the spread of thermal runaway, and improve battery life.

[0069] It should be noted that the bottom heights of the insulating plate 20 and the end heat insulation pad 30 are not the same. The bottom height of the end heat insulation pad 30 is less than that of the insulating plate 20. On the one hand, this is to ensure the path for the intermediate thermally conductive structural adhesive 200 to move towards the insulating plate 20 during the process of the battery module 100 being placed into the box. On the other hand, as the thermally conductive structural adhesive 200 flows towards the insulating plate 20, it fills the height difference between the bottom of the end heat insulation pad 30 and the bottom water-cooling plate 400 and the second channel 21 during the process of extruding air to move towards the sides and top of the battery pack 10. After the thermally conductive structural adhesive 200 has cured, it strengthens the connection between the insulating plate 20, the end heat insulation pad 30 and the battery box, thereby improving the structural strength of the battery module 100 and the battery pack.

[0070] In addition, to avoid the problem of air blockage caused by the thermally conductive structural adhesive 200 filling the sides of the battery pack 10 before the middle position during the extrusion and movement process, the fluid inlet 211 of the insulating plate 20 is designed as a "trumpet mouth" shape with a smaller inner part and a larger outer part. In this way, the thermally conductive structural adhesive 200 in the middle area pushes the air to move to both sides, which can improve the exhaust efficiency and improve the pressing effect of the thermally conductive structural adhesive 200.

[0071] See Figure 1 , Figure 2 , Figure 5 , Figures 10 to 13 The battery pack 10 includes multiple battery cells 11 arranged along the Y direction. A thermal protection structure 12 is provided between each pair of adjacent battery cells 11. The thermal protection structure 12 has a receiving groove 121 on the side of the battery pack near the bottom surface along the Z direction to accommodate thermally conductive structural adhesive 200. The thermal protection structure 12 is used to block heat transfer. When one battery cell 11 experiences thermal runaway, the thermal protection structure 12 can slow down the spread of heat to other battery cells 11. By providing the receiving groove 121 on the side of the thermal protection structure 12 near the bottom surface of the battery pack along the Z direction, the thermally conductive structural adhesive 200 can be accommodated, thereby improving the bonding strength between the battery module 100 and the battery pack.

[0072] In this embodiment, the thermal protection structure 12 includes a phase change material layer 122 and a heat insulation material layer 123 bonded together. The phase change material layer 122 is located on one side of the battery cell 11 along the Y direction, and the heat insulation material layer 123 is located on the other side of the battery cell 11 along the Y direction. The heat insulation material layer 123 provides thermal insulation, slowing the spread of heat to other battery cells 11 when one battery cell 11 experiences thermal runaway. The phase change material layer 122 rapidly absorbs heat, preventing the battery cell 11 from overheating. Simultaneously, the small amount of heat passing through the heat insulation material layer 123 is absorbed by the phase change material layer 122, further ensuring the safety performance of the battery module 100. Because the phase change material layer 122 can absorb heat passing through the heat insulation material layer 123, a thicker heat insulation material layer 123 is unnecessary, reducing costs.

[0073] The relevant battery pack only incorporates heat-insulating materials to prevent thermal runaway. During high-rate charging of the battery cells (reaching 4-6C), the heat generated by the cells cannot be quickly and completely dissipated through the bottom water-cooling plate, causing a rapid temperature rise and affecting fast-charging performance. The thermal protection structure 12 in this embodiment includes a phase change material layer 122 and a heat-insulating material layer 123, with the phase change material layer 122 and the heat-insulating material layer 123 located on both sides of the battery cell 11. This structure provides both heat insulation and rapid heat absorption, without affecting fast-charging performance.

[0074] For example, a buffer frame 124 is provided around the outer periphery of the heat insulation material layer 123. The buffer frame 124 is open on one side of the battery box near the bottom surface along the Z direction to form a receiving groove 121. The buffer frame 124 allows the heat insulation material layer 123 to fit tightly against the battery cell 11, achieving surface-to-surface contact with the battery cell 11 and improving the heat insulation effect. The buffer frame 124 is open on one side of the battery box near the bottom surface along the Z direction to form a receiving groove 121, which facilitates the filling of the thermally conductive structural adhesive 200 and allows the thermally conductive structural adhesive 200 to firmly bond the buffer frame 124 to the heat insulation material layer 123.

[0075] The heat insulation material layer 123 can be silicone foam or aerogel, and the buffer frame 124 can be a silicone frame.

[0076] For example, the phase change material layer 122 includes an aluminum-plastic film shell and a phase change heat insulation material disposed in the aluminum-plastic film shell. At least a portion of the phase change material layer 122 is stacked with a heat-conducting layer 125, which is attached to the battery cell 11. The heat-conducting layer 125 is provided with a receiving groove 121 on the side of the heat-conducting layer 125 along the Z direction near the bottom surface of the battery box.

[0077] Before the phase change temperature of the phase change insulation material is reached, heat is conducted through the material. When the temperature rises to the phase change temperature, the material absorbs a large amount of heat by changing its state of matter while maintaining a constant temperature, thus delaying heat spread. For example, the phase change temperature is between 90 and 130°C.

[0078] The aluminum-plastic film shell encapsulates the internal phase change insulation material through heat pressing. At the edges of the aluminum-plastic film shell, where the heat pressing process only involves the aluminum-plastic film, resulting in a relatively thin layer, a thermally conductive layer 125 is provided to facilitate heat exchange between the battery cell 11 and the edge area of ​​the aluminum-plastic film shell. By attaching the thermally conductive layer 125 to the battery cell 11, at least a portion of the heat from the battery cell 11 can be transferred to the aluminum-plastic film shell through the thermally conductive layer 125, ensuring effective heat exchange.

[0079] In some embodiments, a thermally conductive layer 125 is stacked at the outer peripheral edge of the phase change material layer 122. The thickness of the thermally conductive layer 125 plus the thickness of the edge of the aluminum-plastic film shell equals the thickness of the phase change material layer 122, ensuring that the phase change material layer 122 is fully bonded to the battery cell 11. In some embodiments, a thermally conductive layer 125 is stacked on the outer surface of the phase change material layer 122, and the thermally conductive layer 125 is bonded to the battery cell 11. Because the thermally conductive layer 125 has a certain degree of compressibility, the phase change material layer 122 can abut against the battery cell 11 over a large area, increasing the contact area and improving the heat exchange effect.

[0080] By providing a receiving groove 121 on one side of the thermally conductive layer 125 along the Z direction near the bottom surface of the battery box, it is easy to fill the thermally conductive structural adhesive 200, and the thermally conductive structural adhesive 200 can be used to firmly bond the thermally conductive layer 125 to the phase change material layer 122.

[0081] During production, multiple battery cells 11 are stacked, with a thermal protection structure 12 between adjacent battery cells 11. One side of each battery cell 11 along the Y direction is a phase change material layer 122, and the other side along the Y direction is a heat insulation material layer 123. After setting end heat insulation pads 30 on both sides of the battery pack 10 along the Y direction, an insulating plate 20 is attached to the side of the end heat insulation pads 30 away from the battery pack 10. Then, the battery module 100 is clamped and pressed into the battery box by grippers. The outer side of the insulating plate 20 can abut against the crossbeam or frame of the battery box to constrain the multiple battery cells 11.

[0082] When the battery module 100 is installed into the battery box, a sealed space is formed between the bottom of the battery module 100 and the battery box. When the battery module 100 compresses the thermally conductive structural adhesive 200, the thermally conductive structural adhesive 200 flows through the fluid inlet 211 to the first channel 101, the second channel 21 and both ends of the insulating plate 20, discharging the gas in the thermally conductive structural adhesive 200 and accommodating the overflowing thermally conductive structural adhesive 200. At the same time, the thermally conductive structural adhesive 200 fills the side of the end heat insulation pad 30 along the Z direction near the bottom surface of the battery box, as well as the receiving groove 121 of the thermal protection structure 12.

[0083] For example, when one of the battery cells A experiences thermal runaway, on the one hand, the phase change material layer 122 on one side of battery cell A absorbs the heat released by the thermal runaway, thus cooling down the thermally runaway battery cell A; on the other hand, the heat insulation material layer 123 on the other side of battery cell A blocks the heat from the thermal runaway from being transferred to the normal battery cell B. At the same time, since there is a heat insulation material layer 123 and a phase change material layer 122 between battery cell B and battery cell A, the small amount of thermal runaway energy through the heat insulation material layer 123 will be absorbed again by the phase change material layer 122, further ensuring the safety performance of the normal battery cell B.

[0084] When in normal fast charging mode, most of the heat generated by fast charging is quickly stored in the phase change material layer 122, and a small portion of the heat is exchanged with the bottom thermally conductive structural adhesive 200 and the bottom water cooling plate 400, which reduces the temperature of the battery cell 11 under fast charging.

[0085] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above embodiments. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A battery pack, characterized in that, include: Battery housing; A battery module (100) is located inside the battery housing, and the battery module (100) includes: At least two rows of battery banks (10) and an insulating plate (20) are provided. The at least two rows of battery banks (10) are arranged side by side along the X direction. The insulating plates (20) are respectively provided on both sides of the battery banks (10) along the Y direction. The same end of the at least two rows of battery banks (10) arranged side by side shares an insulating plate (20). The junction of two adjacent rows of battery banks (10) and the insulating plate (20) form a first channel (101). A second channel (21) is provided on the side of the insulating plate (20) facing the battery banks (10) along the Y direction. The fluid inlet (211) of the second channel (21) is located on the side of the insulating plate (20) along the Z direction near the bottom surface of the battery box. The first channel (101) is connected to the fluid inlet (211). Thermally conductive structural adhesive (200) is disposed between the bottom surface of the battery module (100) and the battery housing to bond and fix the two together; When the battery module (100) is installed into the battery housing, the gas in the thermally conductive structural adhesive (200) can be discharged and the overflowing thermally conductive structural adhesive (200) can be contained through the first channel (101) and the second channel (21). The X direction is the width direction of the battery module (100), the Y direction is the length direction of the battery module (100), and the Z direction is the height direction of the battery module (100). The fluid inlet (211) extends along the X direction on the insulating plate (20) and penetrates to at least one end of the insulating plate (20) along the X direction; The second channel (21) extends along the Z direction, and the height of the fluid inlet (211) gradually increases along the Z direction on both sides of the second channel (21) along the X direction away from the second channel (21).

2. The battery pack according to claim 1, characterized in that, A second channel (21) is provided for each row of battery packs (10), and the second channel (21) is located at the middle position of the battery packs (10) along the X direction.

3. The battery pack according to claim 2, characterized in that, The battery module (100) includes two rows of battery bars (10), the first channel (101) is located between two second channels (21), and the height of the fluid inlet (211) gradually increases along the Z direction from the second channel (21) to the first channel (101).

4. The battery pack according to claim 1, characterized in that, Each row of battery packs (10) is provided with end heat insulation pads (30) on both sides along the Y direction. The end heat insulation pads (30) are provided on the side of the insulating plate (20) close to the battery pack (10). The end heat insulation pad (30) is spaced apart from the bottom surface of the battery box along the Z direction to avoid at least part of the fluid inlet (211), and the end heat insulation pads (30) of two adjacent rows of battery bars (10) are spaced apart to avoid the first channel (101).

5. The battery pack according to any one of claims 1-4, characterized in that, The battery pack (10) includes multiple battery cells (11), which are arranged along the Y direction. A thermal protection structure (12) is provided between each two adjacent battery cells (11). The thermal protection structure (12) is provided with a receiving groove (121) on one side of the bottom surface of the battery box along the Z direction to receive the thermally conductive adhesive (200).

6. The battery pack according to claim 5, characterized in that, The thermal protection structure (12) includes a phase change material layer (122) and a heat insulation material layer (123) that are attached to each other. The phase change material layer (122) is on one side of the battery cell (11) along the Y direction, and the heat insulation material layer (123) is on the other side of the battery cell (11) along the Y direction.

7. The battery pack according to claim 6, characterized in that, The outer periphery of the heat insulation material layer (123) is fitted with a buffer frame (124), and the buffer frame (124) is open on one side of the bottom surface of the battery box along the Z direction to form the receiving groove (121).

8. The battery pack according to claim 6, characterized in that, The phase change material layer (122) includes an aluminum-plastic film shell and a phase change heat insulation material disposed in the aluminum-plastic film shell. At least a portion of the phase change material layer (122) is stacked with a thermal conductive layer (125). The thermal conductive layer (125) is attached to the battery cell (11). The thermal conductive layer (125) has the receiving groove (121) disposed on the side of the thermal conductive layer (125) along the Z direction near the bottom surface of the battery box.

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