Battery pack

Abstract

This invention discloses a battery pack comprising: at least one battery module, the battery module including a plurality of electrically connected battery cells; a bracket made of a thermally conductive material, the bracket including a plurality of mounting portions and connecting portions, the connecting portions connecting the plurality of mounting portions together in a relatively fixed manner; the mounting portions forming a receiving cavity for accommodating the battery cells; a plurality of passages pre-set inside the bracket, the plurality of passages being distributed between adjacent mounting portions; and a shell covering the bracket, the shell having airflow holes that communicate with the plurality of passages. This invention optimizes and improves the battery pack, improving the cooling efficiency of the battery cells during the battery cell discharge process, and effectively reducing the temperature of the battery cells and the bracket that directly contacts the battery cells.

Description

Technical Field

[0001] This invention relates to the field of power tool technology, and in particular to a battery pack. Background Technology

[0002] A battery pack is generally a battery module composed of multiple battery cells connected in series or parallel. Furthermore, multiple battery modules can also be connected in series or parallel to form a cell group with a certain voltage and capacity. During discharge, the cells within a battery pack rapidly generate a large amount of heat. If this heat is not dissipated in time before the battery pack is connected to a charger, the charger will not be able to charge the battery pack normally. This is because chargers typically have circuit protection programs; they only activate the charging circuit to perform charging when the battery pack's temperature reaches a predetermined low temperature. Therefore, if the battery pack does not have good heat dissipation performance, the heat generated during discharge cannot be dissipated quickly enough, requiring a significant amount of time to cool down before the next charge. Alternatively, if the charger lacks circuit protection programs, connecting the battery pack to the charger before it has cooled down can damage the battery cells, weaken the battery pack's discharge capacity, shorten its lifespan, and may even lead to safety accidents.

[0003] In the prior art, one way to dissipate heat from the battery pack is to install a battery bracket with heat dissipation function on the outside of the battery pack. The battery bracket is at least partially made of a thermally conductive material so that the heat generated in the battery can be conducted to the battery bracket and then dissipated into the air by the bracket.

[0004] Although the battery holder can dissipate some of the heat generated in the battery into the air, the rapid heat generation during discharge means that, without auxiliary cooling devices such as fans, most of the heat remains on the battery holder, preventing it from quickly dissipating into the air. Furthermore, because the battery cell is in direct contact with the inside of the battery holder, and the cell's temperature is transferred outwards, once the cell and battery holder temperatures reach a similar level, the battery holder will not transfer heat further, meaning the cell surface temperature will not decrease further, thus failing to achieve the desired heat dissipation effect. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention provides a battery pack that can improve the cooling efficiency of the battery cells during the discharge process of the battery cells, and effectively reduce the temperature of the battery cells and the brackets that are in direct contact with the battery cells.

[0006] The above-mentioned objectives of the present invention can be achieved by the following technical solutions:

[0007] A battery pack includes: at least one battery module, the battery module including a plurality of electrically connected battery cells; a bracket made of a thermally conductive material, the bracket including a plurality of mounting portions and connecting portions, the connecting portions connecting the plurality of mounting portions together in a relatively fixed manner, the mounting portions forming a receiving cavity for accommodating the battery cells, the bracket having a plurality of passages pre-set inside the bracket, the plurality of passages being distributed between adjacent mounting portions; and a housing covering the bracket, the housing having airflow holes that can communicate with the plurality of passages.

[0008] Furthermore, the plurality of pathways are independent of the accommodating cavity.

[0009] Furthermore, the battery pack also includes a heat storage element that is at least partially attached to the outside of the bracket, the heat storage element having a specific heat capacity greater than that of the bracket.

[0010] Furthermore, the heat storage element is made of a material with a specific heat capacity greater than 2.6 J / (gK).

[0011] Furthermore, the thermal conductivity of the thermally conductive material is greater than 0.3 W / mk.

[0012] Furthermore, the bracket is provided with a deformable part on the side wall of the mounting part, the outer diameter of the battery cell is smaller than the aperture of the receiving cavity, and after the battery cell is received in the receiving cavity, it is clamped and attached to the receiving cavity by the elastic deformation of the deformable part.

[0013] Furthermore, the deformable portion is at least one protrusion formed inward from the sidewall of the mounting portion.

[0014] Furthermore, the outer diameter of the battery cell is larger than the aperture of the receiving cavity, and the battery cell is set in the receiving cavity of the mounting part by means of thermal compression.

[0015] Furthermore, the battery cell has opposing first end faces and second end faces, as well as a side surface surrounding the first end faces and second end faces, wherein the contact area between the side surface and the mounting portion accounts for at least 80% of the side surface.

[0016] Furthermore, the passages are distributed between the outer walls of adjacent mounting parts, and the minimum spacing between the passages is greater than 1.5 mm.

[0017] Furthermore, the passage extends upward along an axis perpendicular to the battery cell.

[0018] Furthermore, heat sinks are respectively provided on the side walls of the mounting portion on both sides of the passage. The heat sinks are distributed at intervals along the axial direction of the battery cell, and the length of the heat sinks accounts for 3 / 4 of the total axial length of the battery cell.

[0019] Furthermore, the battery pack also includes a heat storage component that is at least partially attached to the outside of the bracket. The heat storage component has a first opening that communicates with the passage and the airflow hole. The outer casing includes an upper cover and a lower cover, and the airflow hole includes an upper opening on the upper cover and a lower opening on the lower cover. The passage extends through the bracket along an axial direction perpendicular to the battery cell.

[0020] Furthermore, the battery pack also includes a clamping member, which presses against the outside of the heat storage element to apply a clamping force to the heat storage element and clamp the bracket. The clamping member is provided with a second opening that communicates with the first opening and the airflow hole. Along the axial direction perpendicular to the battery cell, the first opening and the second opening are distributed on both sides of the passage in order from the inside to the outside. The upper opening, the lower opening, the passage, and the first opening and the second opening cooperate to form a heat dissipation channel.

[0021] Furthermore, the outer casing includes an upper cover and a lower cover, and the airflow hole includes an upper opening on the upper cover and a lower opening on the lower cover; the bracket has an end cap along the axial direction of the battery cell, and the end cap has a third opening; the passage passes through the bracket along the axial direction of the battery cell, and along the axial direction of the battery cell, the lower opening, the upper opening, the third opening, and the passage cooperate to form a heat dissipation channel.

[0022] A battery pack includes: at least one battery module, the battery module including a plurality of electrically connected cells; a bracket made of a thermally conductive material, the bracket including a plurality of mounting portions and a connecting portion, the connecting portion connecting the plurality of mounting portions together in a relatively fixed manner, the mounting portions forming a receiving cavity for accommodating the cells, the bracket having a plurality of passages extending through the bracket along an axial direction perpendicular to the cells; and a housing having airflow holes that communicate with the plurality of passages.

[0023] Furthermore, the plurality of pathways are independent of the accommodating cavity.

[0024] The battery pack provided in this application embodiment improves the structure of the battery pack by forming an independent heat dissipation channel inside the battery pack. This allows for efficient heat dissipation of the bracket and the battery cells that are attached to the bracket inside the battery pack. As a result, the battery pack can be connected to the charger for charging immediately after discharging, thereby saving charging time for users and effectively protecting the battery cells, while improving the discharge capacity and lifespan of the battery pack.

[0025] Specifically, by setting up a bracket with high surface adhesion to the battery cell and made of thermally conductive material, the heat generated by the battery cell during use can be efficiently conducted outward through this heat dissipation channel.

[0026] Furthermore, a heat storage element made of a high specific heat capacity material is attached to the outside of the bracket. This heat storage element can efficiently absorb heat from the bracket, thereby reliably ensuring that the battery cell and the bracket attached to the battery cell do not exceed the temperature limit.

[0027] The improved battery pack extends its operating time and enhances its discharge capacity, making it particularly suitable for harsh high-temperature environments.

[0028] The battery pack of this application has a bracket, a heat storage component and a shell that work together to form a multi-channel parallel direct-blowing heat dissipation channel, which can dissipate heat from the battery cells and the bracket, thereby further controlling the temperature of the inner surface of the battery pack and the bracket. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] Figure 1 This is a schematic diagram of the structure of a battery pack provided in one embodiment of this application;

[0031] Figure 2 yes Figure 1 The battery pack is shown in AA cross-sectional view provided in the document.

[0032] Figure 3 yes Figure 1 The image provided shows a close-up of the battery pack.

[0033] Figure 4 yes Figure 1 The main view of the battery components in the battery pack provided in the image;

[0034] Figure 5 yes Figure 1 An exploded view of the battery components in the battery pack provided in the image;

[0035] Figure 6 This is a schematic diagram of the distribution of heat sinks on the bracket provided in the embodiments of this application;

[0036] Figure 7 yes Figure 1 A structural diagram showing the mating positions of the bracket, seals, and end caps in the battery pack.

[0037] Figure 8 yes Figure 7 A magnified view of a section at point M;

[0038] Figure 9 yes Figure 7 A magnified view of a portion of point N in the middle;

[0039] Figure 10This is a schematic diagram of the structure of a battery pack provided in one embodiment of this application;

[0040] Figure 11 yes Figure 10 The battery pack BB cross-sectional view provided in the document;

[0041] Figure 12 yes Figure 10 The exploded view of the battery pack provided in the image;

[0042] Figure 13 yes Figure 10 Exploded view of the battery components in the battery pack;

[0043] Figure 14 yes Figure 13 A schematic diagram of the structure of the battery pack support;

[0044] Figure 15 yes Figure 14 Front view of the middle support;

[0045] Figure 16 yes Figure 10 A structural diagram showing the mating positions of the bracket, seals, and end caps in the battery pack.

[0046] Figure 17 yes Figure 16 A magnified view of a section at point H.

[0047] Explanation of reference numerals in the attached figures:

[0048] 100. Battery components;

[0049] 1. Battery cell; 11. Conductive sheet; 12. Power supply board;

[0050] 2. Bracket; 20. Mounting part; 21. Receiving cavity; 22. Passage; 23. Deformable part; 24. Connecting part; 241. Heat sink; 25. Sealing end; 251. Extrusion part; 252. Second mounting groove; 26. Abutment part;

[0051] 3. Heat storage component; 31. First opening;

[0052] 4. Outer shell; 42. Top cover; 420. Top opening; 43. Bottom cover; 430. Bottom opening; 44. First side panel; 45. Second side panel; 46. First side cover; 47. Second side cover;

[0053] 5. Clamping component; 51. Second opening;

[0054] 6. Heat dissipation channels;

[0055] 7. Sealing element; 71. First sealing part; 72. Second sealing part;

[0056] 8. End cap; 80. First mounting slot; 81. Third opening; 82. Third mounting slot. Detailed Implementation

[0057] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

[0058] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0059] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0060] This application specification provides an improved battery pack that, compared with the prior art, can improve the cooling efficiency of the battery cells during the discharge process, effectively reduce the temperature of the battery cells and the brackets that are in direct contact with the battery cells, and improve the discharge capacity of the battery pack.

[0061] Please refer to the following for comprehensive information. Figures 1 to 12 This application specification provides a battery pack, which mainly includes: a battery cell 1, a bracket 2, a housing 4, a sealing device, and some components for installation. Among them, for example... Figure 5 or Figure 10 As shown, at least the battery cell 1, the bracket 2, and the sealing device can form a battery assembly 100 installed in the housing 4.

[0062] In this specification, the number of battery cells 1 and the series / parallel connection method between battery cells 1 can be adjusted according to the voltage of the battery cell 1 itself and different nominal voltages, and this application does not make specific limitations here. Specifically, the battery cells 1 can be connected in series, in parallel, or in a combination of series and parallel connections through conductive sheets 11 to form a battery module. The number of battery modules can be one, two, or more.

[0063] Please refer to the following: Figure 2 In one implementation, there can be two battery modules (one on the left and one on the right). Each battery module has eight battery cells (e.g., ...). Figure 5 As shown, another battery module has 7 cells. Furthermore, the two battery modules are connected in series via a 12-phase power supply board to output 60V voltage.

[0064] Please refer to the following: Figure 9 In another embodiment, the number of battery modules is also two. The two battery modules can be connected in parallel via a 12-phase power supply board. Each battery module can contain 15 4-volt cells 1, which are connected in series to form a cell group with a nominal voltage of 60 volts. The two battery modules are then connected in parallel, so the output voltage remains 60V, but the current is twice that of the 15 cells connected in series.

[0065] Specifically, the outer casing 4 may include an upper cover 42, a lower cover 43, and a first side plate 44, a second side plate 45, a first side cover 46, and a second side cover 47 disposed between the upper cover 42 and the lower cover 43. The first side plate 44 and the second side plate 45 are disposed opposite to each other, and the first side cover 46 and the second side cover 47 are disposed opposite to each other.

[0066] The outer casing 4 is provided with airflow holes for introducing and expelling outside air from the battery pack. Specifically, the airflow holes may include an upper opening 420 on the upper cover 42 and a lower opening 430 on the lower cover 43. In use, the airflow holes of the outer casing 4, together with other structures in the battery pack, form a heat dissipation channel 6 to cool the battery cells 1 and the support 2.

[0067] The battery cell 1 has a first end face and a second end face facing each other, as well as side surfaces surrounding the first end face and the second end face. The battery cell 1 can be cylindrical; however, its shape can be adapted to actual needs, for example, it can be a cuboid, a near-cuboid, or even other irregular shapes. This application does not specifically limit the shape or structure of the battery cell 1. In this specification, a cylindrical shape is mainly used as an example; the shapes of other battery cells can be compared analogously to this application.

[0068] In the prior art, a typical battery cell 1 has a skin on its surface, which is generally made of an insulating material with poor thermal conductivity (e.g., plastic). Furthermore, when the battery cell 1 has a skin, because the skin is wrapped around the outer surface of the battery cell 1, it cannot be completely fitted to the battery cell 1. This results in at least some air gaps easily forming between the skin and the battery cell 1. These air gaps, along with the poor thermal conductivity of the skin, affect the outward heat conduction of the battery cell 1.

[0069] In this specification, in order to conduct heat away from the battery cell 1 as efficiently as possible, the outer surface of the battery cell 1 is peeled off, i.e., no outer skin is installed. Subsequently, the peeled battery cell 1 is directly attached and installed in the bracket 2 to improve heat conduction efficiency.

[0070] In this specification, the bracket 2 is mainly used to mount the battery cell 1. The bracket 2 is made of a thermally conductive material, which can conduct heat from the battery cell 1 to the outside in a timely manner. Specifically, in order to ensure that the bracket 2 has good thermal conductivity, the thermal conductivity of the thermally conductive material is greater than 0.3 W / mK.

[0071] To improve the stability of the bracket 2 structure and reduce installation difficulty, the bracket 2 can be an integral bracket, which can be integrally molded or made into parts and then assembled together. Of course, this specification does not exclude the possibility of the bracket 2 being a separate structure. The specific heat capacity of the bracket 2 is greater than 1.8 J / (gK) to ensure that the bracket 2 can absorb heat from the battery cell 1 with high efficiency. Combined with its high thermal conductivity, it can quickly conduct the absorbed heat outwards. Specifically, the material of the bracket 2 can be polypropylene (PP), high-density polyethylene (HDPE), low-density polyethylene (LDPE), etc.

[0072] In this specification, the bracket 2 may include a plurality of mounting portions 20, each mounting portion 20 having a receiving cavity 21 formed inside for accommodating the battery cell 1. Specifically, the number of mounting portions 20 may be the same as or greater than the number of battery cells 1. The battery cell 1 is at least partially fitted and mounted in the receiving cavity 21.

[0073] This specification primarily uses an integral bracket 2 as an example for illustration; other types of brackets 2 can be described by analogy. The integral bracket 2 has multiple mounting portions 20, which can be arranged in a predetermined order. For example, multiple mounting portions 20 can be arranged at intervals in a first direction to form a row of mounting portions 20; in a second direction perpendicular to the first direction, multiple rows of mounting portions 20 can be arranged at intervals to form an array of mounting portions 20. Of course, the mounting portions 20 can also be arranged in other orders according to actual usage needs; this application does not impose a unique limitation.

[0074] The bracket 2 has several pre-set passages 22 running through it, distributed between adjacent mounting portions 20. The "inside" of the bracket 2 refers to the area enclosed by the center lines connecting the outermost cells 1 of the battery module. These passages 22 are independent of the receiving cavity 21. When the passages 22 used for airflow and heat dissipation are independent and not connected to the receiving cavity 21 for housing the cells 1, the cells 1 can utilize the heat-conducting bracket 2 itself to conduct heat, resulting in high thermal conductivity.

[0075] Compared to the case where the airflow passage 22 and the receiving cavity 21 are not independent of each other, i.e., the airflow passage 22 and the receiving cavity 21 are connected, the airflow passage 22 mainly utilizes air for heat conduction, and the thermal conductivity of air is not as high as that of the heat-conducting support 2, resulting in poor heat conduction. Furthermore, when the passage 22 and the receiving cavity 21 are independent of each other, it is also beneficial for the subsequent installation of the waterproof sealing structure. Compared to the case where the passage 22 and the receiving cavity 21 are not independent of each other, it is less likely to interfere with the waterproof sealing structure.

[0076] Specifically, the mounting part 20 can be a cavity with a certain wall thickness. The hollow portion of the cavity is the receiving cavity 21. The mounting part 20 includes a side wall, a positioning port, and a mounting port opposite to the positioning port.

[0077] In one embodiment, the outer diameter of the battery cell 1 is larger than the aperture of the receiving cavity 21, and the battery cell 1 can be disposed in the receiving cavity 21 of the mounting part 20 by means of thermal compression.

[0078] When the battery cell 1 is placed in the receiving cavity 21 by thermo-pressing, the outer diameter of the battery cell 1 is larger than the aperture of the receiving cavity 21. The initial surface area of ​​the receiving cavity 21 in the bracket 2 is smaller than the outer surface area of ​​the battery cell 1. After the battery cell 1 is installed into the receiving cavity 21 by thermo-pressing, the outer surface of the battery cell 1 can be directly and completely attached to the side wall inside the mounting part 20. The percentage of the attached area to the side area (i.e., the degree of attachment) can be close to 100%.

[0079] In another embodiment, the bracket 2 is provided with a deformable part 23 on the side wall of the mounting part 20, the outer diameter of the battery cell 1 is smaller than the aperture of the receiving cavity 21, and the battery cell 1 is clamped in the receiving cavity 21 after elastic deformation through the mounting part 20 provided with the deformable part 23.

[0080] Specifically, the deformable portion 23 can be at least one protrusion formed inward from the side wall of the mounting portion 20. When the battery cell 1 undergoes elastic deformation through the deformable portion 23 on the side wall of the mounting portion 20 and is clamped in the receiving cavity 21, the initial surface area of ​​the receiving cavity 21 in the bracket 2 is larger than the outer surface area of ​​the battery cell 1. After the battery cell 1 is installed into the receiving cavity 21 by pressing the deformable portion 23, the outer surface of the battery cell 1 can be mostly directly attached to the side wall inside the mounting portion 20, with a fitting degree of more than 80%.

[0081] like Figure 4 As shown, one or two protrusions are used as examples. The protrusion can be located on the side relatively close to the mounting opening. When the battery cell 1 is inserted through the mounting opening, the protrusion undergoes elastic deformation, securing the battery cell 1 within the mounting portion 20 simultaneously, ensuring that the outer surface of the battery cell 1 fits snugly against the receiving cavity 21 of the mounting portion 20. Furthermore, even if the battery pack vibrates during use, the elastic deformation of the protrusion ensures that each battery cell 1 remains tightly fitted within the receiving cavity 21 of the mounting portion 20.

[0082] Furthermore, the deformable portion 23 can also be an opening provided on the side wall of the mounting portion 20. By providing this opening, the mounting portion can be deformed, thereby allowing it to fit better with the battery cell 1. Of course, the form of the deformable portion 23 is not limited to the examples described above.

[0083] Overall, regardless of the installation method used, it is necessary to ensure that the contact area between the side surface of each battery cell 1 and the mounting part 20 accounts for at least 80% of the side surface, so as to ensure that the heat generated by the battery cell 1 during operation can be quickly conducted to the bracket 2.

[0084] In this specification, the battery pack may further include a heat storage element 3 that is at least partially attached to the outside of the bracket 2. The heat storage element 3 may be made of a material with high heat absorption capacity and large specific heat capacity. Specifically, the specific heat capacity of the heat storage element 3 is greater than that of the bracket 2, and the heat storage element 3 is at least partially attached to the outside of the bracket 2, enabling it to efficiently absorb heat from the bracket 2, thereby ensuring that the temperature of the bracket 2 and the battery cell 1 attached to the bracket 2 does not exceed the limit. When the battery pack is placed on the charger, the large amount of heat accumulated in the heat storage element 3 can be cooled by activating the charger's fan.

[0085] Specifically, the heat storage element 3 is made of a high specific heat capacity heat storage material with a specific heat capacity greater than 2.6 J / (gK). This high specific heat capacity material is a non-phase change material, for example, any of the following: polymer materials, high thermal conductivity materials, or silicone; of course, the high specific heat capacity material can also be a phase change material. When the heat storage element 3 is a non-phase change high specific heat capacity material, it can absorb heat with a stable specific heat capacity parameter during the heat absorption process, and no phase change will occur during the heat absorption process. When the heat storage element 3 does not undergo a phase change during the heat absorption process, it can not only maintain high heat absorption efficiency, but also simplify the overall structure of the battery pack. When a phase change material is used as the main material of the heat storage element 3, since it will undergo a state change during use, for example, from a solid to a molten state, the structure needs to provide a cavity to accommodate the phase change material, or the phase change material needs to be sealed.

[0086] In this application specification, a connecting portion 24 is provided between two adjacent mounting portions 20 in the bracket 2. Specifically, the connecting portion 24 is integrally formed with the sealing end 25. The connecting portion 24 is located at the end near the mounting portion 20. The ends of the plurality of mounting portions 20 form the two ends of the bracket 2.

[0087] To ensure the waterproof sealing performance of the battery cell 1 in the battery pack, sealing devices are provided at both ends of the bracket 2. Specifically, the ends of the plurality of mounting portions 20 form the two ends (i.e., sealing ends 25) of the bracket 2. The sealing device includes a sealing element 7 and an end cap 8. The sealing element 7 is disposed between the sealing end 25 and the end cap 8 to reliably seal the battery cell 1. The shape and structure of the sealing element 7 are mainly determined based on the shape of the receiving space formed after the end cap 8 and the sealing end 25 are engaged and the position to be sealed. The sealing end 25 can be an annular protrusion at the end of the bracket 2, which can be integrally formed with the bracket 2, or the protrusion can be fixed to the end of the bracket 2 by a detachable connection. Figure 5 As shown, when the end cap 8 does not have an opening, the sealing element 7 can be in the form of a sealing ring with a certain wall thickness. Figure 13 As shown, when the end cap 8 has an opening, the sealing element 7 can be in the form of a sealing sheet with an opening.

[0088] The battery pack contains heat dissipation channels 6. Please refer to the relevant documentation. Figures 1 to 6 In some embodiments, the airflow direction in the heat dissipation channel 6 can be perpendicular to the axial direction of the battery cell 1. In this embodiment, a passage 22 is formed between the outer walls of two adjacent mounting portions 20 with a predetermined gap. The passage 22 extends along an axial direction perpendicular to the battery cell 1, and a first opening 31 communicating with the predetermined passage 22 and the airflow hole is provided on the side wall of the heat storage member 3.

[0089] The heat storage component 3 may include a first part and a second part, which can be detachably connected or fixed to the outside of the bracket 2 by means of other limiting methods. The inner surfaces of the first and second parts can match the outer surfaces of the bracket 2. The first and second parts are provided with a first opening 31 that communicates with the passage 22.

[0090] The passage 22 is used to cooperate with the first opening 31 of the heat storage element 3 in the battery pack and the airflow holes of the outer casing 4, thereby forming a heat dissipation channel 6. The connecting part 24 is located near the end face of the cell 1. Along the axial direction of the cell 1, except for the location of the connecting part 24, the passage 22 between the two connecting parts 24 at the ends can be used for airflow. When a relatively long passage 22 is formed between the cells 1 of the battery pack, it is beneficial to ensure that the battery pack has a better heat dissipation effect during use.

[0091] In this embodiment, the passages are distributed between the outer walls of adjacent mounting parts, and the minimum spacing between the passages is greater than 1.5 mm in order to meet the heat dissipation requirements.

[0092] like Figure 6 As shown, furthermore, to ensure good heat dissipation effect of the heat dissipation channel on the bracket 2, heat sinks 241 are respectively provided on the side walls of the mounting portions 20 located between the connecting portions 24. The heat sinks are distributed at intervals along the axial direction of the battery cell 1. The heat sinks 241 of two adjacent mounting portions 20 are arranged facing each other to form a central heat dissipation area. The heat sinks 241 are mainly used to quickly transfer the heat conducted from the battery cell 1 to the bracket 2 outward through the heat dissipation channel 6. In order to maximize the heat dissipation effect of the heat sinks 241, the length of the heat sinks 241 is 3 / 4 of the total axial length of the battery cell 1.

[0093] Furthermore, considering that the heat sink 241 is installed within the space where the passage 22 is located, in order to ensure that the central heat dissipation area where the heat sink 241 is located has a better cooling effect on the bracket 2 during airflow, the distance between the outer walls of the two mounting parts 20 should not be too small, generally not less than 5 mm. Considering that the overall size of the battery pack should not be too large, especially due to the limitation of installation space, the outer shell size of the battery pack should not be too large. Generally, the distance between the outer walls of the two mounting parts 20 should not be too large, generally not greater than 15 mm. Overall, with the heat sink 241 installed, the distance of the passage 22 along the axis perpendicular to the battery cell 1 is between 5 mm and 15 mm.

[0094] like Figure 5As shown, in some embodiments, the battery pack may also be provided with a clamping member 5. The clamping member 5 presses against the outside of the heat storage member 3 to apply a clamping force to the heat storage member 3 to secure the bracket 2.

[0095] In this embodiment, the clamping member 5 can be made of a rigid material. The clamping member 5 can adhere to the outer surface of the heat storage member 3, thereby reliably fitting the heat storage member 3 to the support 2 and ensuring efficient heat absorption by the heat storage member onto the support 2. Specifically, the clamping member 5 has an inner side relatively close to the heat storage member 3 and an outer side relatively far from the heat storage member 3. The inner side of the clamping member 5 and the outer side of the heat storage member 3 can have similar shapes, ensuring that the clamping member 5 can reliably act on the outer surface of the heat storage member 3, preventing clamping failure due to vibration or other uncontrollable factors during use.

[0096] Specifically, the clamping member 5 can be divided into two interlocking parts, which can be fixed together by a detachable connection. The detachable connection can be a bolt, screw, or other feasible connection method, and this application does not make a specific limitation here.

[0097] When the heat storage component 3 is attached and fixed to the outside of the bracket 2 by the clamping component 5, the clamping component 5 may be provided with a second opening 51 that communicates with the first opening 31 and the airflow hole.

[0098] like Figure 2 and Figure 5 As shown, specifically, along the axial direction perpendicular to the cell 1, the first opening 31 and the second opening 51 are distributed on both sides of the mounting portion 20 in an order from the inside to the outside. The upper opening 420, the lower opening 430, and the passage 22 cooperate with the first opening 31 and the second opening 51 to form a heat dissipation channel 6. After entering the battery pack through the lower opening 430, outside air flows sequentially through the second opening 51, the first opening 31, the passage 22, the first opening 31, and the second opening 51, and then flows out of the battery pack through the upper opening 420.

[0099] The second opening 51 can be directly opposite the first opening 31. The airflow hole is directly opposite the passage 22 between the mounting part 20. The external airflow passes through the airflow hole on the outer shell 4, flows through the second opening 51 and the first opening 31, and is directly guided to the central heat dissipation area corresponding to the passage 22. Then it flows outward from the outer shell 4 through the first opening 31 and the second opening 51, forming the heat dissipation channel 6. Overall, the heat dissipation channel 6 is a multi-path parallel direct-blowing heat dissipation channel 6 formed by multiple parallel short-path flow channels, which can directly and efficiently act on each mounting part 20 of the bracket 2, thereby enabling efficient heat dissipation of the bracket 2 and the battery cell 1 located in the bracket 2.

[0100] In some embodiments, the battery pack may not require a separate clamping member 5. The outer casing 4 can be directly pressed against the heat storage member 3, thereby attaching the heat storage member 3 to the outer surface of the bracket 2. Furthermore, the heat dissipation channel 6 is mainly formed by the airflow holes on the outer casing 4, the first opening 31 on the heat storage member 3, and the central heat dissipation area between the mounting portion 20.

[0101] This specification also provides a battery pack, which may include: at least one battery module, the battery module including: a plurality of electrically connected battery cells 1; a bracket 2 made of thermally conductive material, the bracket 2 including a plurality of mounting portions 20 and a connecting portion 24, the connecting portion 24 connecting the plurality of mounting portions 20 together in a relatively fixed manner, the mounting portions 20 forming a receiving cavity 21 for accommodating the battery cells 1, the bracket 2 having a plurality of passages 22 extending through the bracket 2 along an axial direction perpendicular to the battery cells 1; and a housing 4, the housing 4 having airflow holes that can communicate with the plurality of passages 22.

[0102] In this embodiment, the specific shape, structure, and relative position of the battery cell 1, the support 2 made of thermally conductive material, and the outer casing 4 contained in the battery are described in detail in the above embodiments, and will not be repeated here.

[0103] In this embodiment, the battery pack has a passage formed in the support 2 that extends along the axial direction of the vertical cell 1. This passage is used to cooperate with the airflow holes on the outer casing 4 to form a heat dissipation channel 6 for cooling the support 2 and the cell 1 disposed within the support 2. Since the heat dissipation channel 6 and the sealing devices located at both ends of the support 2 are spatially independent and do not affect each other, the difficulty of setting the sealing device can be reduced, and the sealing device can reliably seal the cell 1.

[0104] like Figure 7 As shown, the sealing device is respectively disposed on both sides of the sealing end 25 of the bracket 2. The sealing device includes an end cap 8 and a sealing element 7. Wherein, as... Figure 8As shown, when the conductive sheet 11 does not need to be led out on one side of the bracket 2, a compression part 251 can be provided at the sealing end 25. Specifically, the compression part 251 can be an annular protrusion formed on the outer surface of the sealing end 25. Of course, the compression part 251 can also be other shapes or other arrangements, which are not specifically limited here. A first mounting groove 80 for installing the sealing element 7 is provided on the end cover 8. During assembly, the sealing element 7 is installed in the first mounting groove 80 of the end cover 8, and then the end cover 8 with the sealing element 7 can be connected to the sealing end 25 of the bracket 2 through a connector. The compression part 251 at the sealing end 25 can contact the sealing element 7, and under the extrusion force formed after the end cover 8 and the bracket 2 cooperate, the sealing element 7 undergoes elastic deformation, thereby achieving a seal.

[0105] like Figure 9 As shown, when the conductive sheet 11 needs to be led out of the end cap on the other side of the bracket 2, in order to improve the sealing at the point where the conductive sheet 11 protrudes, a second mounting groove 252 can be formed at the sealing end 25, and an abutment 26 with elastic deformation capability can be provided in the second mounting groove 252. Specifically, one end of the abutment 26 extends into the second mounting groove 252, and the other end contacts the sealing element 7. Under the squeezing force formed after the end cap 8 and the bracket 2 are engaged, both the abutment 26 and the sealing element 7 undergo elastic deformation. Compared with non-deformable or rigid abutments, the elastic abutment 26 can better eliminate the gap between the end cap 8 and the bracket 2. Specifically, the abutment 26 can be in the form of EVA foam, O-ring, heat shrink tubing, etc. Of course, it can also be in other forms with elastic deformation capability, and this application does not make specific limitations here.

[0106] Furthermore, to ensure the sealing of the mating positions, such as to better guarantee the sealing of the protruding part of the conductive sheet 11 and achieve waterproofing, the abutment 26 can be formed by injecting adhesive into the second mounting groove 252. Additionally, seals can also be formed at other mating positions by injecting adhesive to ensure the reliability of the seal at the desired location.

[0107] like Figures 10 to 15 As shown, in some embodiments, the airflow direction in the heat dissipation channel 6 can be parallel to the axial direction of the battery cell 1. A third opening 81 is provided on the end cap 8. Specifically, as... Figure 14 and Figure 15 As shown, the passage 22 extends through the bracket along the axial direction of the battery cell 1. Specifically, the passage 22 can be located in the area enclosed by four adjacent mounting portions 20, and the passage 22 is not connected to the receiving cavity between the mounting portion 20, thereby ensuring the sealing of the battery cell 1.

[0108] like Figure 13As shown, when the end cap 8 is provided with a third opening 81, the sealing member 7 includes a first sealing part 71 for matching with the third opening 81 of the end cap 8 and the passage 22 of the bracket 2, and a second sealing part 72 for matching with the sealing end 25 of the end cap 8 and the bracket 2.

[0109] Specifically, the first sealing part 71 can be annular, disposed between the passage 22 of the bracket 2 and the third opening 81 of the end cap 8. It serves two purposes: firstly, to provide a circumferential seal between the passage 22 of the bracket 2 and the mounting part 20; and secondly, to act as an intermediate connecting part, connecting the third opening 81 and the passage 22. The inner diameter of the first sealing part 71 can be equal to or slightly larger than the diameters of the third opening 81 and the passage 22. The second sealing part 72 can be a sealing ring with a certain wall thickness, disposed between the sealing end cap 8 and the sealing end 25 of the bracket 2 to achieve a seal. The first sealing part 71 and the second sealing part 72 can be integrally formed or separately disposed; this application does not impose any specific limitations on this.

[0110] Along the axial direction of the battery cell 1, the third opening 81 is distributed at both ends of the battery cell 1. The lower opening 430, the upper opening 420, the third opening 81, and the passage 22 cooperate to form a heat dissipation channel 6. Outside air can enter the battery pack through the lower opening 430, flow through the third opening 81, the passage 22, and out of the battery pack through the upper opening 420.

[0111] In this embodiment, the heat dissipation channel 6 is also a multi-path parallel direct-blowing heat dissipation channel formed by multiple parallel short-path flow channels. The difference from the above embodiment is that the gas flow direction in the heat dissipation channel 6 is generally parallel to the axial direction of the battery cell 1. Overall, the heat dissipation channel 6 is a multi-path parallel direct-blowing heat dissipation channel, and the airflow flowing through it can directly and efficiently act on each mounting portion 20 of the bracket 2, thereby efficiently dissipating heat from the bracket 2 and the battery cell 1 located within it.

[0112] Please refer to the following: Figure 16 and Figure 17 The passage 22 formed in the bracket 2 is parallel to the axial direction of the battery cell 1. Therefore, the sealing device provided at the sealing end 25 of the bracket 2 not only needs to have a sealing function, but also needs to cooperate with the passage 22 of the bracket 2 and the outer shell 4 to form a heat dissipation channel 6.

[0113] Specifically, a first mounting groove 80 is formed on the inner surface of the outer periphery of the end cap 8 that mates with the bracket 2. The first mounting groove 80 is used to install the second sealing part 72. A pressing part 251 is provided on the outer surface of the sealing end 25 of the bracket 2 that faces the first mounting groove 80. Specifically, the pressing part 251 can be an annular protrusion formed on the outer surface of the sealing end 25. Of course, the pressing part 251 can also be other shapes or other arrangements, which are not specifically limited here.

[0114] Furthermore, the third opening 81 on the end cap 8 is directly opposite the passage 22 of the bracket 2. A third mounting groove 82 is formed on the inner side of the end cap 8 that mates with the bracket 2; this third mounting groove 82 is used to mount the first sealing part 71. Correspondingly, a pressing part 251 is also provided on the outer surface of the sealing end 25 of the bracket 2 that faces the third mounting groove 82. Specifically, the pressing part 251 can also be an annular protrusion formed on the outer surface of the sealing end 25.

[0115] During assembly, the first sealing part 71 and the second sealing part 72 are respectively installed in the third mounting groove 82 and the first mounting groove 80 of the end cover 8. Then, the end cover 8 with the sealing element 7 can be connected to the sealing end 25 of the bracket 2 through the connector. The pressing part 251 at the sealing end 25 can contact the sealing element 7. Under the pressing force formed after the end cover 8 and the bracket 2 are engaged, the sealing element 7 undergoes elastic deformation. This not only achieves waterproof sealing of the sealing end 25 of the bracket 2, but also does not affect the connectivity between the passage 22 in the bracket 2 and the airflow hole of the outer shell 4.

[0116] In a specific application scenario, such as for high-power DC tools in high-temperature environments, the ambient temperature is high, and the tool itself has high power and generates a lot of heat. At this time, the heat generated in the battery pack cannot be dissipated in time, resulting in insufficient battery pack discharge capacity, which cannot meet the usage requirements of high-function DC tools under high temperatures.

[0117] The battery pack provided in this application, by incorporating a support 2 made of thermally conductive material with high surface adhesion to the battery cell 1, can efficiently conduct the heat generated by the battery cell 1 during use outwards. Furthermore, a heat storage element 3 made of a high specific heat capacity material is attached to the outer side of the support 2. This heat storage element 3 can efficiently absorb the heat in the support 2, thereby reliably ensuring that the battery cell 1 and the support 2 attached to the battery cell 1 do not exceed the temperature limit. This improved battery pack can extend the battery pack's operating time and improve its discharge capacity during use.

[0118] Furthermore, the battery pack bracket 2, heat storage component 3 and outer casing 4 of this application cooperate to form a multi-channel parallel direct-blowing heat dissipation channel, which can dissipate heat from the battery cell 1, thereby further controlling the temperature of the inner surface of the battery pack and bracket 2.

[0119] It should be noted that in the description of this application, the terms "first," "second," etc., are used only for descriptive purposes and to distinguish similar objects; there is no order between them, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "multiple" means two or more.

[0120] The various embodiments described in this specification are presented in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0121] The above descriptions are merely a few embodiments of the present invention. Although the embodiments disclosed in the present invention are as described above, the content is only for the purpose of facilitating understanding of the present invention and is not intended to limit the present invention. Any person skilled in the art to which this invention pertains may make any modifications and changes in the form and details of the embodiments without departing from the spirit and scope disclosed in the present invention. However, the patent protection scope of the present invention shall still be determined by the scope defined in the appended claims.

Claims

1. A battery pack, characterized in that, It includes: At least one battery module, the battery module comprising a plurality of electrically connected cells; A bracket made of thermally conductive material includes multiple mounting parts and connecting parts. The connecting parts connect the multiple mounting parts together in a relatively fixed manner. Each mounting part forms a receiving cavity for accommodating one of the battery cells. The bracket has several passages pre-set inside the bracket, and the several passages are distributed between adjacent mounting parts. An outer shell covering the support is provided with airflow holes that can communicate with the plurality of passages.

2. The battery pack as described in claim 1, characterized in that, The plurality of pathways are independent of the cavity.

3. The battery pack as described in claim 1, characterized in that, It also includes a heat storage element that is at least partially attached to and installed on the outside of the bracket, wherein the specific heat capacity of the heat storage element is greater than that of the bracket.

4. The battery pack as described in claim 3, characterized in that, The heat storage element is made of a material with a specific heat capacity greater than 2.6 J / (g·K).

5. The battery pack as described in claim 1, characterized in that, The thermal conductivity of the thermally conductive material is greater than 0.3 W / mk.

6. The battery pack as described in claim 1, characterized in that, The bracket has a deformable part on the side wall of the mounting part. The outer diameter of the battery cell is smaller than the aperture of the receiving cavity. After the battery cell is received in the receiving cavity, it is clamped and attached to the receiving cavity by the elastic deformation of the deformable part.

7. The battery pack as described in claim 6, characterized in that, The deformable portion is at least one protrusion formed inward from the side wall of the mounting portion.

8. The battery pack as claimed in claim 1, characterized in that, The outer diameter of the battery cell is larger than the aperture of the receiving cavity, and the battery cell is set in the receiving cavity of the mounting part by means of thermal compression.

9. The battery pack as described in claim 6 or 8, characterized in that, The battery cell has a first end face and a second end face opposite to each other, and a side surface surrounding the first end face and the second end face, wherein the contact area between the side surface and the mounting portion accounts for at least 80% of the side surface.

10. The battery pack as claimed in claim 1, characterized in that, The passages are distributed between the outer walls of adjacent mounting parts, and the minimum spacing between the passages is greater than 1.5 mm.

11. The battery pack as claimed in claim 1, characterized in that: The passage extends upward along an axis perpendicular to the cell.

12. The battery pack as claimed in claim 11, characterized in that: Heat sinks are respectively provided on the side walls of the mounting portion on both sides of the passage. The heat sinks are distributed at intervals along the axial direction of the battery cell, and the length of the heat sinks accounts for 3 / 4 of the total axial length of the battery cell.

13. The battery pack as claimed in claim 11, characterized in that: It also includes a heat storage component that is at least partially attached to the outside of the bracket, and the heat storage component is provided with a first opening that communicates with the passage and the airflow hole; The outer casing includes an upper cover and a lower cover opposite to each other, and the airflow hole includes: an upper opening provided on the upper cover and a lower opening provided on the lower cover; The passage runs through the bracket along an axis perpendicular to the cell.

14. The battery pack as claimed in claim 13, characterized in that, It also includes a clamping member, which presses against the outside of the heat storage member to apply a clamping force to the heat storage member to hold the bracket in place. The clamping member is provided with a second opening that communicates with the first opening and the airflow hole. Along the axial direction perpendicular to the battery cell, the first opening and the second opening are distributed on both sides of the passage in order from the inside to the outside; the upper opening, the lower opening, the passage, and the first opening and the second opening cooperate to form a heat dissipation channel.

15. The battery pack as claimed in claim 1, characterized in that, The housing includes an upper cover and a lower cover, and the airflow hole includes an upper opening on the upper cover and a lower opening on the lower cover. The bracket has an end cap along the axial direction of the battery cell, and the end cap has a third opening. The passage extends through the bracket along the axial direction of the battery cell. Along the axial direction of the battery cell, the lower opening, the upper opening, the third opening, and the passage cooperate to form a heat dissipation channel.

16. A battery pack, characterized in that, It includes: At least one battery module, the battery module comprising a plurality of electrically connected cells; A bracket made of thermally conductive material includes multiple mounting parts and connecting parts. The connecting parts connect the multiple mounting parts together in a relatively fixed manner. Each mounting part forms a receiving cavity for accommodating one of the battery cells. The bracket has a plurality of passages that pass through it, and the plurality of passages extend along an axis perpendicular to the battery cell. An outer shell covering the support is provided with airflow holes that can communicate with the plurality of passages.

17. The battery pack as claimed in claim 16, characterized in that, The plurality of pathways are independent of the cavity.

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