Battery pack

Abstract

The utility model discloses a battery pack. The battery pack comprises a battery assembly, a battery box and a convergence assembly, and the first cooling flow channel on the bottom wall, the battery core cooling flow channel and the cooling confluence flow channel of the confluence assembly form a path for cooling the battery monomers entering and exiting the battery assembly, so that the cooling of the battery monomers is realized. The first cooling flow channel is formed on the bottom wall, so that the cooling flow channel is prevented from being arranged in the accommodating space of the battery box, the internal space of the battery box is maximized, the energy density of a battery pack can be improved, and the number of structural parts of the battery box is reduced; a large amount of gas released during thermal runaway of the single batteries can enter the gas confluence flow channel of the confluence assembly and then is discharged out of the battery pack, so that safety accidents such as fire and explosion of the whole battery pack are avoided. And the cooling medium in the cooling confluence flow channel has a cooling effect on the gas in the gas confluence flow channel, so that the temperature of the gas is reduced, and the diffusion of thermal runaway is delayed.

Description

TECHNICAL FIELD

[0001] The utility model relates to lithium battery technical field especially, relates to a battery pack. BACKGROUND

[0002] The new energy lithium battery industry of our country develops rapidly, especially in the new energy automobile field and energy storage field, and the demand along with the development increases, and the market expects high rate charge and discharge of the battery, and it is well known that the temperature rise rate of the battery cell is extremely fast during high rate charge and discharge, and the temperature safety threshold can be reached in a short time.

[0003] However, when high rate charge and discharge causes thermal runaway of the single battery cell, it is difficult to avoid heat diffusion. How to consider the design of the thermal management system and the heat discharge system becomes a difficulty of the battery pack. UTILITY MODEL CONTENT

[0004] The utility model provides a battery pack, and the battery pack comprises a battery assembly, a battery box and a current collection assembly.

[0005] The battery assembly comprises a plurality of battery monomers arranged along a first direction and / or a second direction, and a spacer is arranged between adjacent battery monomers, the spacer comprises opposite and spaced first and second end portions, the first and second end portions are clamped between adjacent battery monomers to form a battery cell cooling flow channel, or the spacer is provided with the battery cell cooling flow channel, wherein one of the first and second directions is the length direction of the battery box, and the other is the width direction of the battery box.

[0006] The battery box comprises a box body and a box cover sealingly connected to an opening of the box body, the battery assembly is arranged in the box body, a first cooling flow channel is arranged in the inner bottom wall of the box body, and one end of the first cooling flow channel is sealingly communicated with the battery cell cooling flow channel.

[0007] The current collection assembly is located between the battery assembly and the box cover, the current collection assembly is provided with a gas current collection flow channel and a cooling current collection flow channel, the gas current collection flow channel and the cooling current collection flow channel are independent of each other, the cooling current collection flow channel is sealingly communicated with the other end of the battery cell cooling flow channel, and the gas current collection flow channel is sealingly communicated with the explosion-proof valve of each battery monomer.

[0008] As an implementation manner, a plurality of first communication holes are arranged in the first cooling flow channel along the length extension direction of the first cooling flow channel, the first communication holes are located in the region between adjacent battery monomers, and the ports of the corresponding battery cell cooling flow channels are communicated.

[0009] As an implementation manner, a plurality of first cooling flow channels are arranged side by side in the bottom wall,

[0010] The side wall of the box is provided with a second cooling flow channel, which is in communication with the first cooling flow channel, or the side wall of the box is provided with at least two second cooling flow channels, and at least part of the second cooling flow channels are connected with the first cooling flow channels one by one.

[0011] As an implementation manner, the second cooling flow channel has a second communication hole extending along the length direction of the side wall,

[0012] In the orthographic projection of the bottom wall, each of the first cooling flow channels has a port located in the projection range of the second communication hole, and the port is in communication with the second communication hole.

[0013] As an implementation manner, a distribution bending part is protruded on the inner surface of the side wall, the distribution bending part and the inner surface of the side wall enclose a downward notch groove, and the notch of the groove is in sealing fit with the bottom wall to form the first cooling flow channel.

[0014] As an implementation manner, the distribution bending part is provided with an opening, an adapter passes through one end of the side wall and is in communication with the opening, the other end is in communication with one of a first joint and a second joint, the other of the first joint and the second joint is in communication with the cooling flow channel, and the first joint, the first cooling flow channel, the battery cell cooling flow channel, the cooling flow channel and the second joint form a path for circulating the cooling medium.

[0015] As an implementation manner, the cooling flow channel is provided with a plurality of first liquid holes spaced apart along the length extension direction thereof, each of the first liquid holes is located in the region between adjacent battery monomers, and is in communication with the port of the corresponding battery cell cooling flow channel.

[0016] As an implementation manner, the flow assembly includes a flow body and two first flow guides, the flow body is provided with a plurality of cooling flow channels side by side, the first flow guide has a fourth cooling flow channel,

[0017] The two first flow guides are respectively arranged on both sides of the flow body, so that each cooling flow channel has one port in communication with one fourth cooling flow channel and another port in communication with another fourth cooling flow channel.

[0018] As an implementation manner, the partition further includes a partition part connecting the first end part and the second end part, and the partition part divides the battery cell cooling flow channel into at least two battery cell sub-cooling flow channels.

[0019] As an implementation manner, a sealing fixing part is further included, and the sealing fixing part includes a first sealing fixing part and a second sealing fixing part.

[0020] The first sealing fixing member is clamped between the battery assembly and the bottom wall of the box body to enable the first cooling flow channel to be in sealed communication with one end of the cell cooling flow channel; and the second sealing fixing member is clamped between the battery assembly and the bus assembly to enable the cooling bus flow channel to be in sealed communication with the other end of the cell cooling flow channel.

[0021] The utility model also provides a battery pack heat management device, including heat management unit and above-mentioned battery pack, the heat management unit passes through adjusting the flow rate of cooling medium in the first cooling flow channel, cell cooling flow channel of battery pack, with adjusting the temperature of battery pack.

[0022] The above scheme, through the first cooling flow channel on the bottom wall, the cell cooling flow channel and the cooling bus flow channel of the bus assembly, the paths of the battery assembly into and out of the battery monomer are formed, and the cooling of the battery monomer is realized. The bottom wall itself forms the first cooling flow channel, which avoids the cooling flow channel in the accommodation space of the battery box, maximizes the space inside the battery box, improves the energy density of the battery pack, reduces the number of structural parts of the battery box, and helps to improve the assembly efficiency of the battery box. When the battery monomer is in thermal runaway, a large amount of gas released can enter the gas bus flow channel of the bus assembly and then be discharged outside the battery pack, avoiding safety accidents such as fire and explosion of the whole battery pack. In addition, the cooling medium in the cooling bus flow channel has a cooling effect on the gas in the gas bus flow channel, so that the temperature of the gas decreases, the spread of thermal runaway is delayed, and the possibility of fire or explosion of the battery pack is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0023] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments made with reference to the accompanying drawings:

[0024] Figure 1 A schematic view of the battery pack provided by the utility model embodiment is shown in the figure;

[0025] Figure 2 An explosion schematic view of the battery pack provided by the utility model embodiment is shown in the figure;

[0026] Figure 3 A partial explosion schematic view of the battery pack provided by the utility model embodiment is shown in the figure;

[0027] Figure 4 is Figure 3 A partial enlarged schematic view of the figure;

[0028] Figure 5 A cross-sectional schematic view of the battery pack provided by the utility model embodiment is shown in the figure;

[0029] Figure 6The utility model provides a schematic view of battery box provided by the embodiment of the utility model;

[0030] Figure 7 is Figure 6 A-A direction section view of

[0031] Figure 8 The utility model provides an explosion schematic view of battery box provided by the embodiment of the utility model;

[0032] Figure 9 The utility model provides a schematic view of right side wall provided by the embodiment of the utility model;

[0033] Figure 10 The utility model provides a schematic view of sub bottom wall provided by the embodiment of the utility model;

[0034] Figure 11 The utility model provides a schematic view of confluence subassembly provided by the embodiment of the utility model;

[0035] Figure 12 The utility model provides a bottom view schematic view of confluence subbody provided by the embodiment of the utility model;

[0036] Figure 13 The utility model provides a left view of sub confluence body provided by the embodiment of the utility model;

[0037] Figure 14 The utility model provides a schematic view between adjacent battery monomer provided by the embodiment of the utility model Figure 1 ;

[0038] Figure 15 The utility model provides a schematic view between adjacent battery monomer provided by the embodiment of the utility model Figure 2 ;

[0039] Battery box 10, box 11, box cover 12, first containing cavity 101, second containing cavity 102;

[0040] Right side wall 111, liquid separation bending part 1111, second communication hole 1111a, gap 11111, first mounting hole 1112, second mounting hole 1113, second cooling flow channel a1, back wall 112, front wall 113, left wall 114, third mounting hole 1141;

[0041] Bottom wall 115, sub bottom wall 11501, first cooling flow channel a2, first hollow structure 1151, first communication hole 1152, the port 1153 of first cooling flow channel, first partition plate 116, fourth hollow structure 1161, first exhaust channel b2, second communication hole 11611, second partition plate 117;

[0042] Battery assembly 20, battery cell 21, explosion-proof valve 211, cell cooling flow channel 201, cell sub-cooling flow channel 2011, separator 22, first end 221, second end 222, separation part 223;

[0043] Sealing fixture 30, first sealing fixture 31, second sealing fixture 32, third sealing fixture 33.

[0044] Busbar assembly 40, busbar body 41, busbar sub-body 401, second hollow structure 411 cooling busbar flow channel a3, third cooling flow channel 411, first liquid hole 4111, third hollow structure 412, gas busbar flow channel b1, first gas hole 4121, second gas hole 4122, first flow guide 42, fourth cooling flow channel a4, second flow guide 43, fifth cooling flow channel a5.

[0045] First joint 51, second joint 52, pressure relief valve 53, adapter 54. DETAILED DESCRIPTION

[0046] The application will be further described below in conjunction with the drawings and examples. It can be understood that the specific examples described herein are only used to explain the related utility model, and not to limit the utility model. In addition, it should be noted that only parts related to the utility model are shown in the drawings for ease of description.

[0047] It should be noted that the examples in the present application and the features in the examples can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in conjunction with the examples.

[0048] At least refer to Figures 1-15 As shown in the drawings, the utility model example provides a battery pack, comprising: a battery assembly 20, a battery box 10 and a busbar assembly 40.

[0049] The battery assembly 20 comprises a plurality of battery cells 21 arranged along a first direction or / and a second direction, and an electric cell cooling flow channel 201 is formed between adjacent battery cells 21, wherein one of the first direction and the second direction is the length direction of the battery box 10, and the other is the width direction of the battery box 10.

[0050] The battery box 10 comprises a box body 11 and a box cover 12 sealingly connected to the opening of the box body 11, and the battery assembly 20 is placed in the box body 11. The bottom wall 115 of the box body 11 is internally provided with a first cooling flow channel a2, and the first cooling flow channel a2 is sealingly communicated with one end of the electric cell cooling flow channel 201.

[0051] The current-converging assembly 40 is located between the battery assembly 20 and the box cover 12, and is provided with a gas current-converging flow channel b1 and a cooling current-converging flow channel a3, which are independent of each other. The cooling current-converging flow channel a3 is in sealed communication with the other end of the cell cooling flow channel 201. The gas current-converging flow channel b1 is in sealed communication with the explosion-proof valve 211 of each battery monomer 21.

[0052] The battery monomer 21 can be a square battery, a soft package battery or a cylindrical battery, and the following embodiments take the square battery as an example.

[0053] The plurality of battery monomers 21 can be arranged in a rectangular array, as shown in Figure 3 The plurality of battery monomers 21 are arranged in columns along a first direction, and 4 columns are arranged side by side along a second direction to form the above-mentioned rectangular array.

[0054] In each column, any two adjacent battery monomers 21 are provided with a cell cooling flow channel 201 for heat transfer with the battery monomer 21. For example, as shown in Figure 14 and Figure 15 The battery assembly 20 further comprises a partition 22 clamped between the adjacent two battery monomers 21. The partition 22 comprises opposite and spaced first and second end portions 221 and 222 clamped between the opposite surfaces of the adjacent battery monomers 21, and the first and second end portions 221 and 222 and the opposite surfaces of the two battery monomers 21 form the above-mentioned cell cooling flow channel 201.

[0055] Of course, it can be understood that if the partition 22 itself is a cavity structure, the cavity of the partition 22 is the above-mentioned cell cooling flow channel 201.

[0056] In this way, the battery monomer 21 itself serves as part of the cell cooling flow channel 201, so that the cooling medium in the cell cooling flow channel 201 can directly contact the outer surface of the battery monomer 21, forming a direct cooling type. In other words, as shown in Figure 3 The battery monomer 21 is immersed in the cooling medium in the cell cooling flow channel 201 on the left and right sides, which is equivalent to an immersion type cell cooling structure, and does not need to use a separate cooling plate to cooperate with the battery monomer 21, which not only makes the heat transfer efficiency higher, but also is suitable for high-rate charging and discharging use scenarios, and can also reduce the number of structural parts in the battery assembly 20, and improve the energy density of the battery pack.

[0057] In addition, as shown in Figure 14 and Figure 15As shown, the partition 22 further comprises a partition portion 223 connecting the first end portion 221 and the second end portion 222, and the partition portion 223 divides the cell cooling flow channel 201 into two cell sub-cooling flow channels 2011. The partition portion 223 can equally or unequally divide the cell cooling flow channel 201. In this way, when one of the two adjacent battery monomers 21 occurs thermal runaway, the partition portion 23 can prevent the thermal runaway battery monomer 21 from affecting the other battery monomer 21, and inhibit the spread of thermal runaway.

[0058] It should be noted that the first end portion 221, the second end portion 222 and the partition portion 223 can be but not limited to integrally formed, and the partition 22 can be but not limited to injection molded by using high-temperature-resistant insulating materials.

[0059] As shown in Figure 3 , the box body 11 has a receiving cavity, which includes a first receiving cavity 101 and a second receiving cavity 102, the first receiving cavity 101 is used to place the battery assembly 20, and the second receiving cavity 102 is used to place the battery management module, and each battery monomer 21 is electrically connected with the battery management module.

[0060] In specific embodiments, as shown in Figure 6 and Figure 8 , the box body 11 comprises a bottom wall 115 and a plurality of side walls arranged around the bottom wall 115. The side walls and the bottom wall 115 are welded to each other, so that the positions where the side walls and the bottom wall 115 are connected have good sealing performance. The plurality of side walls comprises a left side wall 114, a rear side wall 112, a right side wall 111 and a front side wall 113. The bottom wall 115 and the plurality of side walls can be but are not limited to hollow aluminum profiles, so that the weight of the entire box body 11 can be reduced. Considering the processing technology of the bottom wall 115, in order to reduce the processing difficulty and processing cost of the bottom wall 115, the bottom wall 115 is composed of a plurality of sub-bottom walls 11501 which are spliced and welded.

[0061] As shown in Figure 6 and Figure 8 , a second partition plate 117 is arranged in the box body 11, the length of the second partition plate 117 is arranged along the second direction, and the second partition plate 117 divides the receiving cavity into the first receiving cavity 101 and the second receiving cavity 102 which are independent of each other.

[0062] As shown in Figure 6 , Figure 8 and Figure 10As shown, since the sub-bottom wall 11501 is a hollow aluminum profile, a plurality of first hollow structures 1151 are arranged inside the sub-bottom wall 11501. One of the first hollow structures 1151 in the sub-bottom wall 11501 is taken as a first cooling flow channel a2, which extends in the first direction. A plurality of first communication holes 1152 are arranged on the surface of the sub-bottom wall 11501 in contact with the battery assembly 20, each first communication hole 1152 is arranged equidistantly along the length direction of the first cooling flow channel a2, and each first communication hole 1152 is in communication with the first cooling flow channel a2. The first communication hole 1152 is located in the region between two adjacent battery monomers 21, that is, the first communication hole 1152 is in communication with the lower port of the corresponding cell cooling flow channel 201. As shown in Figure 6 and Figure 7 Thus, the cooling medium in the first cooling flow channel a2 can enter the cell cooling flow channel 201 of the battery assembly 20 to realize heat transfer between the cooling medium and the battery monomer 21.

[0063] It should be noted that the bottom wall 115 itself forms the first cooling flow channel a2, which avoids arranging the cooling flow channel in the first accommodating cavity 101, maximizes the internal space of the battery box 10, improves the energy density of the battery pack, reduces the number of structural parts of the battery box 10, and helps to improve the assembly efficiency of the battery box 10.

[0064] As shown in Figure 11 and Figure 12 The current collecting assembly 40 can be but not limited to a plate shape. The current collecting assembly 40 is located above the battery assembly 20, the current collecting assembly 40 is orthographically projected on the battery assembly 20, and the projection of the current collecting assembly 40 covers at least the battery assembly 20. The current collecting assembly 40 is provided with a gas current collecting flow channel b1 and a cooling current collecting flow channel a3, which are independent of each other. The gas current collecting flow channel b1 and the cooling current collecting flow channel a3 both extend in the second direction,

[0065] As shown in Figure 12 A plurality of first liquid holes 4111 are arranged equidistantly along the length direction of the cooling current collecting flow channel a3, and each first liquid hole 4111 is in communication with the cooling current collecting flow channel a3. Each first liquid hole 4111 is located in the region between two adjacent battery monomers 21, that is, the first liquid hole 4111 is in communication with the upper port of the corresponding cell cooling flow channel 201. Thus, the cooling medium in the cell cooling flow channel 201 can enter the cooling current collecting flow channel a3 to realize the discharge of the cooling medium from the battery assembly 20.

[0066] A plurality of first gas holes 4121 are arranged on the gas collecting flow channel b1 at equal intervals along the length direction of the gas collecting flow channel b1, and each first gas hole 4121 is in communication with the gas collecting flow channel b1. The first gas hole 4121 is arranged in correspondence with the explosion-proof valve 211 of the battery monomer 21 in an up-down direction and is in communication with the explosion-proof valve 211. Thus, when the battery monomer 21 is in thermal runaway, a large amount of gas released by the battery monomer 21 can enter the gas collecting flow channel b1 and then be discharged to the outside of the battery pack, thereby avoiding safety accidents such as fire and explosion of the whole battery pack. At the same time, since the explosion-proof valve 211 of each battery monomer 21 is in communication with the gas collecting flow channel b1, when a certain battery monomer 21 is in thermal runaway, the gas discharged by the battery monomer 21 will not affect other battery monomers 21 and will not be in contact with the cooling medium, thereby realizing directional exhaust of the battery monomer 21 in thermal runaway.

[0067] In summary, the first cooling flow channel a2 on the bottom wall 115, the cell cooling flow channel 201, and the cooling collecting flow channel a3 of the collecting assembly 40 are combined with each other, thereby forming a path for cooling the battery monomers 21 entering and exiting the battery assembly 20, and realizing cooling of the battery monomers 21. The bottom wall 115 itself forms the first cooling flow channel a2, which avoids the need to provide a cooling flow channel in the accommodation space of the battery box 10, maximizes the space inside the battery box 10, improves the energy density of the battery pack, reduces the number of structural components of the battery box 10, and helps to improve the assembly efficiency of the battery box 10. When the battery monomers 21 are in thermal runaway, a large amount of gas released by the battery monomers 21 can enter the gas collecting flow channel b1 of the collecting assembly 40 and then be discharged to the outside of the battery pack, thereby avoiding safety accidents such as fire and explosion of the whole battery pack. In addition, the cooling medium in the cooling collecting flow channel a3 has a cooling effect on the gas in the gas collecting flow channel b1, so that the temperature of the gas decreases, the spread of thermal runaway is delayed, and the possibility of fire or even explosion of the battery pack is reduced.

[0068] As an implementation manner, a plurality of first cooling flow channels a2 are arranged side by side in the bottom wall 115. The side wall of the box body 11 is provided with a second cooling flow channel a1, and the second cooling flow channel a1 is in communication with each first cooling flow channel a2.

[0069] In specific embodiments, as shown in FIG. 1, Figure 6 , Figure 8 and Figure 9As shown, four first cooling flow channels a2 are arranged side by side on the bottom wall 115 in the front-rear direction. A distribution bending part 1111 is arranged on the inner surface of the right side wall 111, that is, the distribution bending part 1111 is located in the first accommodating cavity 101. The cross section of the distribution bending part 1111 can be L-shaped. The distribution bending part 1111 extends in the front-rear direction, and the front end of the distribution bending part 1111 is welded to the front side wall 113; the rear end of the distribution bending part 1111 is welded to the rear side wall 112. In this way, the distribution bending part 1111 and the inner surface of the right side wall 111 form a downwardly open long groove, and the opening of the groove is welded to the bottom wall 115, thereby forming the second cooling flow channel a1.

[0070] In the structure in which the second cooling flow channel a1 and each first cooling flow channel a2 are in communication, the second cooling flow channel a1 has a second communication hole 1111a extending along the length direction of the right side wall, the cross section of the second communication hole 1111a is rectangular, and the length of the second communication hole 1111a is equal to the length of the distribution bending part 1111. In the orthographic projection of the bottom wall 115, each first cooling flow channel a2 has a port 1153 located in the projection range of the second communication hole 1111a, and the port 1153 is in communication with the second communication hole 1111a. In this way, as shown in Figure 5 and Figure 7 each first cooling flow channel a2 can enter the cooling medium based on the second cooling flow channel a1 at the same time, so that each battery cell 21 in the battery module 20 is cooled, and the temperature of each battery cell 21 is substantially the same.

[0071] Of course, it can be understood that in some embodiments, at least two second cooling flow channels a1 can be arranged on the side wall of the box body 11, and at least part of the second cooling flow channels a1 are connected to each first cooling flow channel a2 one by one.

[0072] In addition, as shown in Figure 8 and Figure 9 an opening 11111 is arranged at the top of the distribution bending part 1111, and a first mounting hole 1112 is arranged on the right side wall 111. The adapter 54 passes through the first mounting hole 1112, and the adapter 54 is fixedly connected to the first mounting hole 1112. One end of the adapter 54 is in communication with the opening 1112, and the other end is in communication with the first joint 51. The first joint 51 can be a joint for introducing the cooling medium, and the cooling medium is introduced from the first joint 51 and is distributed to each first cooling flow channel a2 through the second cooling flow channel a1.

[0073] As an implementation manner, the cooling collecting flow channel a3 is provided with a plurality of first liquid holes 4111 along the length extension direction of the cooling collecting flow channel a3, each first liquid hole 4111 is located in the region between adjacent battery cells 21, and is in communication with the port of the corresponding cell cooling flow channel 201.

[0074] In specific embodiments, as shown in Figures 11-13 The bus assembly 40 includes a bus body 41, two first flow guides 42 and a second flow guide 43. The bus body 41 is plate-shaped and includes a plurality of bus sub-bodies 401, which can be but are not limited to hollow aluminum profiles, and the bus sub-bodies 401 are spliced and welded to form the bus body 41.

[0075] Figure 13 As shown in The bus sub-body 401 is provided with a plurality of second hollow structures 411 and a plurality of third hollow structures 412, one second hollow structure 411 being a cooling bus flow channel a3 and one third hollow structure 412 being a gas bus flow channel b1. The cooling bus flow channels a3 and the gas bus flow channels b1 are arranged alternately in the first direction. In this way, the cooling medium in the cooling bus flow channels a3 cools the gas in the gas bus flow channels b1, so that the temperature of the gas decreases, the spread of thermal runaway is delayed, and the possibility of fire or even explosion of the battery pack is reduced.

[0076] Figure 12 As shown in The cooling bus flow channels a3 are provided with a plurality of first liquid holes 4111 at equal intervals along the length extension direction thereof, each first liquid hole 4111 being located in the region between adjacent battery monomers 21 and being in communication with the upper port of the corresponding cell cooling flow channel 201. Thus, the cooling medium that has completed heat transfer with the battery assembly 20 can be discharged in time.

[0077] Figure 12 As shown in The gas bus flow channels b1 are provided with a plurality of first gas holes 4121 at equal intervals along the length extension direction thereof, each first gas hole 4121 being in communication with the explosion-proof valve 211 of the corresponding battery monomer 21.

[0078] Figure 11 As shown in The first flow guide 42 has a fourth cooling flow channel a4, the length direction of the first flow guide 42 is parallel to the length direction of the bus body 41, and the two first flow guides 42 are arranged on the front and rear sides of the bus body 41 respectively. The fourth cooling flow channel a4 of the first flow guide 42 located on the rear side is in communication with one port of each third cooling flow channel 411, and the fourth cooling flow channel a4 of the first flow guide 42 located on the front side is in communication with the other port of each third cooling flow channel 411.

[0079] The second flow guide 43 has a fifth cooling flow channel a5, the length direction of the second flow guide 43 is parallel to the width direction of the bus body 41, and the second flow guide 43 is located on the right side of the bus body 41. The two ports of the fifth cooling flow channel a5 of the second flow guide 43 are in communication with the fourth cooling flow channels a4 of the two first flow guides 42 respectively.

[0080] Figure 8 and Figure 11As shown, the third mounting hole 1141 is arranged on the left side wall 114, the second joint 52 passes through the third mounting hole 1141 and communicates with the second flow guide 43, and the second joint 52 is mounted on the left side wall 114. The second joint 52 can be a joint for discharging cooling medium, and the cooling medium in the current collector body 41 can enter the front first flow guide 42 or the rear first flow guide 42, and the two first flow guides 42 can accelerate the cooling medium to flow out of the current collector body 41, thereby avoiding affecting the outflow of the cooling medium in the cell cooling flow channel 201. Finally, the cooling medium enters the third flow guide 43 and is discharged from the battery pack from the second joint 52. In this way, the first joint 51, the first cooling flow channel a2, the cell cooling flow channel 201, the cooling current collector flow channel a3 and the second joint 52 form a path for circulating the cooling medium.

[0081] Of course, it can be understood that the second joint 52 can also be a joint for introducing cooling medium, and correspondingly, the first joint 51 can be a joint for discharging cooling medium.

[0082] In actual application, the service life of the battery monomer 21 will be affected by the temperature used by the battery monomer 21, and the battery monomer 21 is not suitable for working in high-temperature and low-temperature conditions. Based on this, the first joint 51 and the second joint 52 are respectively communicated with the thermal management unit, and the thermal management unit is used to adjust the flow rate of the cooling medium, so that the battery monomer 21 is in a suitable use temperature.

[0083] For example, the BMS can monitor the temperature change of the battery monomer 21 in the battery pack in real time, and can transmit data to the thermal management unit in real time. The thermal management unit starts to control the heating or cooling cycle to be started according to the feedback data of the BMS, and can control the flow rate of the cooling medium during the cycle process, so as to ensure that the battery monomer 21 is in the best working state, thereby improving the service life of the battery monomer 21, and the control strategy is as follows:

[0084] When the temperature of the battery monomer 21 is ≤15℃, it is judged that the battery monomer 21 is in a low-temperature working condition, at this time, the temperature of the battery monomer 21 should be increased, so the heating cycle is started, and the battery monomer 21 is configured with different cooling medium flow rates at different temperatures, for example, when the temperature is ≤10℃, the cooling medium flow rate is 10L / min, and when the temperature is ≤5℃, the cooling medium flow rate is 20L / min;

[0085] When the temperature of the battery monomer 21 is ≥40℃, it is judged that the battery monomer 21 is in a high-temperature working condition, at this time, the temperature of the battery monomer 21 should be reduced, so the cooling cycle is started, and the flow rate of the cooling medium is controlled according to the temperature of the battery monomer 21, for example, when the temperature is ≥45℃, the cooling medium flow rate is 10L / min, and when the temperature is ≥50℃, the cooling medium flow rate is 20L / min;

[0086] When the battery monomer 21 triggers thermal runaway, the battery monomer 21 will reach a high temperature of several hundred degrees Celsius. When the temperature of the battery monomer 21 is greater than or equal to 100°C, it is determined that the battery monomer 21 triggers thermal runaway. At this time, the flow rate of the cooling medium should be adjusted to an extreme speed, for example, 30 L / min or 50 L / min.

[0087] Optionally, in an embodiment, the battery box 10 comprises an exhaust member (not shown). The exhaust member can pass through the box body 11 and be mounted on the box body 11, or pass through the box cover 12 and be mounted on the box cover 12. The exhaust member is in communication with each gas confluence flow channel b1, and the exhaust member discharges the gas outside the battery box 10, thereby avoiding safety accidents such as fire and explosion of the entire battery pack.

[0088] Optionally, in another embodiment, at least one first partition plate 116 is arranged in the battery box 10, and a first exhaust channel b2 is arranged in the first partition plate 116, and the first exhaust channel b2 is in communication with each gas confluence flow channel b1.

[0089] In detail, as shown in Figure 6 , a first partition plate 116 is arranged in the box body 11, the length of the first partition plate 116 is arranged along the first direction, and the first partition plate 116 divides the second accommodating cavity 102 into mutually independent second sub-accommodating chambers, and the first partition plate 116 divides the first accommodating cavity 101 into a plurality of mutually independent first sub-accommodating chambers. For example, the first partition plate 116 divides the first accommodating cavity 101 into two mutually independent first sub-accommodating chambers. When the battery monomer 21 in the first sub-accommodating chamber on the front side triggers thermal runaway, the first partition plate 116 can play a blocking role to avoid the battery monomer 21 in the first sub-accommodating chamber on the rear side from being affected.

[0090] As shown in Figure 5 and Figure 6 , the first partition plate 116 can be but is not limited to a hollow aluminum profile, and the first partition plate 116 is provided with a plurality of fourth hollow structures 1161, and one fourth hollow structure 1161 serves as a first exhaust channel b2. A plurality of third communication holes 11611 are arranged on the surface of the first partition plate 116 facing the confluence assembly 40, each third communication hole 11611 is in communication with the first exhaust channel b2, and each third communication hole 11611 is arranged at equal intervals along the length direction of the first partition plate 116.

[0091] Each gas confluence flow channel b1 is also provided with a second gas hole 4122 located at the middle of the length direction of the gas confluence flow channel b1. The second gas hole 4122 is in communication with the third communication hole 11611, as shown in Figure 5The gas in the current-converging assembly 40 can enter the inside of the first partition plate 116 from the second gas hole 4122 and the third communication hole 11611, so that the gas in the current-converging assembly 40 can be discharged in time.

[0092] As shown in Figure 5 、 Figure 8 and Figure 9 , the right side wall 111 is provided with a second mounting hole 1113. The pressure relief valve 53 communicates with the first exhaust channel b2 through the second mounting hole 1113, and the pressure relief valve 53 is mounted on the right side wall 111. The gas is discharged from the battery pack through the pressure relief valve 53.

[0093] As an implementation manner, the battery pack further comprises a sealing fixing piece 30, which can be but is not limited to sealing glue. The sealing fixing piece 30 comprises a first sealing fixing piece 31, a second sealing fixing piece 32 and a third sealing fixing piece 33.

[0094] As shown in Figure 3 、 Figure 4 , the first sealing fixing piece 31 is clamped between the battery assembly 20 and the bottom wall 115 of the box body 11, so that the first cooling flow channel a2 is in sealed communication with the lower port of the cell cooling flow channel 201; the second sealing fixing piece 32 is clamped between the battery assembly 20 and the current-converging assembly 40, so that the first cooling flow channel a2 is in sealed communication with the upper port of the cell cooling flow channel 201; and the third sealing fixing piece 33 is clamped between the first partition plate 116 and the current-converging assembly 40, so that the gas current-converging flow channel b1 is in sealed communication with the explosion-proof valve 211 of the battery monomer 21.

[0095] The sealing fixing piece 30 has the functions of sealing and fixing the battery monomer 21, so that the battery monomers 21 are arranged in an array, the CTP group stacking mode is avoided, the number of parts is reduced, and the manufacturing cost is reduced.

[0096] The utility model example further provides a kind of battery pack thermal management device, and the device includes thermal management unit and above-mentioned battery pack, and thermal management unit passes through adjusting the flow rate of cooling medium in the first cooling flow channel a2 of battery pack, cell cooling flow channel 201, to adjust the temperature of battery pack. The battery pack thermal management device has the advantages of the above-mentioned battery pack, so it is not repeated.

[0097] It should be understood that the above-mentioned terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0098] The above description is only the preferred embodiment of the present application and the explanation of the technical principles applied. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the utility model. For example, the technical solutions formed by mutually replacing the above-mentioned features and the technical features disclosed in the present application (but not limited to) with similar functions.

Claims

1. A battery pack, characterized by, The battery pack comprises: a battery assembly (20) comprising a plurality of battery monomers (21) arranged along a first direction and / or a second direction, a separator (22) being arranged between adjacent battery monomers (21), the separator (22) comprising opposite and spaced first and second end portions (221, 222), the first and second end portions (221, 222) being clamped between adjacent battery monomers (21) to form a cell cooling flow channel (201), or the separator (22) being provided with the cell cooling flow channel (201); a battery box (10) comprising a box body (11) and a box cover (12) sealingly connected to an opening of the box body (11), the battery assembly (20) being arranged in the box body (11), a first cooling flow channel (a2) being arranged inside a bottom wall (115) of the box body (11), the first cooling flow channel (a2) being sealingly communicated with one end of the cell cooling flow channel (201), wherein one of the first and second directions is the length direction of the battery box (10), and the other is the width direction of the battery box (10); a current collection assembly (40) located between the battery assembly (20) and the box cover (12), the current collection assembly (40) being provided with a gas current collection flow channel (b1) and a cooling current collection flow channel (a3), the gas current collection flow channel (b1) and the cooling current collection flow channel (a3) being independent of each other, the cooling current collection flow channel (a3) being sealingly communicated with the other end of the cell cooling flow channel (201); the gas current collection flow channel (b1) is sealingly communicated with the explosion-proof valve (211) of each battery monomer (21).

2. The battery pack according to claim 1, wherein: a plurality of first communication holes (1152) are arranged in the first cooling flow channel (a2) along the length direction thereof, the first communication holes (1152) being located in the region between adjacent battery monomers (21) and being communicated with the ports of the corresponding cell cooling flow channel (201).

3. The battery pack of claim 2, wherein, a plurality of first cooling flow channels (a2) are arranged side by side in the bottom wall (115), a second cooling flow channel (a1) is arranged on the side wall of the box body (11), the second cooling flow channel (a1) being communicated with the first cooling flow channel (a2), or at least two second cooling flow channels (a1) are arranged on the side wall of the box body (11), at least part of the second cooling flow channels (a1) being connected one by one with the first cooling flow channels (a2).

4. The battery pack of claim 3, wherein, the second cooling flow channel (a1) has a second communication hole (1111a) extending along the length direction of the side wall, in the orthographic projection of the bottom wall (115), each first cooling flow channel (a2) has a port located in the projection range of the second communication hole (1111a), the port being communicated with the second communication hole (1111a).

5. The battery pack of claim 4, wherein, A liquid distribution bending part (1111) is protruded on the inner surface of the side wall, and the liquid distribution bending part (1111) and the inner surface of the side wall enclose a downward notch groove, and the notch of the groove is in sealing cooperation with the bottom wall (115) to form the first cooling flow channel (a2).

6. The battery pack of claim 5, wherein, The liquid distribution bending part (1111) is provided with an opening (11111), the adapter (54) passes through one end of the side wall and communicates with the opening (11111), the other end communicates with one of the first joint (51) and the second joint (52), and the other of the first joint (51) and the second joint (52) communicates with the cooling collecting flow channel (a3). The first joint (51), the first cooling flow channel (a2), the battery cell cooling flow channel (201), the cooling collecting flow channel (a3) and the second joint (52) form a path for circulating the cooling medium.

7. The battery pack of any one of claims 1-6, wherein, The cooling collecting flow channel (a3) is provided with a plurality of first liquid holes (4111) at intervals along the length extension direction thereof, each of the first liquid holes (4111) is located in the region between adjacent battery monomers (21), and communicates with the port of the corresponding battery cell cooling flow channel (201).

8. The battery pack of claim 7, wherein, The collecting assembly (40) comprises a collecting body (41) and two first flow guides (42), the collecting body (41) is provided with a plurality of cooling collecting flow channels (a3) side by side, the first flow guide (42) has a fourth cooling flow channel (a4), The two first flow guides (42) are respectively arranged on both sides of the collecting body (41), so that each cooling collecting flow channel (a3) has one port in communication with one fourth cooling flow channel (a4) and the other port in communication with another fourth cooling flow channel (a4).

9. The battery pack of any one of claims 1-6, wherein, The partition (22) further comprises a partition part (223) connecting the first end part (221) and the second end part (222), and the partition part (223) divides the battery cell cooling flow channel (201) into at least two battery cell sub-cooling flow channels (2011).

10. The battery pack of any one of claims 1-6, wherein, Further comprising a sealing fixing part (30), the sealing fixing part (30) comprises a first sealing fixing part (31) and a second sealing fixing part (32); The first sealing fixing part (31) is clamped between the battery assembly (20) and the bottom wall (115) of the box body (11), so that the first cooling flow channel (a2) and one end of the battery cell cooling flow channel (201) are in sealing communication; The second sealing fixing part (32) is clamped between the battery assembly (20) and the collecting assembly (40), so that the cooling collecting flow channel (a3) and the other end of the battery cell cooling flow channel (201) are in sealing communication.

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