Battery packs and energy storage devices

Abstract

The present application provides a battery pack and an energy storage device. The battery pack includes a housing, a battery cell assembly, a first circuit board, a first heat dissipation channel, a first guide channel, a first guide member and a fan. The housing includes a peripheral side wall, a front wall and a rear wall. The front wall has a first vent. The rear wall has a second vent. The battery cell assembly includes a battery cell. The battery cell includes a battery cell housing and two electrode terminals. The electrode terminal includes a welding portion. At least one welding portion of each battery cell is connected to the first circuit board. The first heat dissipation channel is located between the peripheral side wall and the battery cell housing. The first circuit board and the welding portion are exposed to the first heat dissipation channel. Along the first direction, the first guide channel is located on one side of the battery cell assembly. The first guide channel connects the first heat dissipation channel and the second vent. The first guide member serves as at least a partial component forming the first guide channel. The fan is connected to the housing. The fan is configured to pass the refrigerant through the first vent, the first heat dissipation channel, the first guide channel and the second vent.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery pack and an energy storage device. Background Art

[0002] A battery pack is a device that can be used to activate the active materials by charging after the battery cell is discharged. The battery pack can be used for energy storage devices. In the development of battery technology, how to ensure the safety of battery packs is one of the research directions in battery technology. Summary of the invention

[0003] In view of the above problems, the present application provides a battery pack and an energy storage device, which are beneficial to improving the safety of the battery pack.

[0004] The present application provides a battery pack, which includes a shell, a battery cell assembly, a first circuit board, a first heat dissipation channel, a first guide channel, a first guide member and a fan. The shell includes a peripheral side wall, a front wall and a rear wall spaced apart along a first direction. The front wall has a first vent. The rear wall has a second vent. The battery cell assembly includes a plurality of battery cells. Each battery cell includes a battery cell shell and two electrode terminals. Each electrode terminal includes a welding portion. At least one welding portion of each battery cell is connected to the first circuit board. The first heat dissipation channel is located between the peripheral side wall and the battery cell shell. The first circuit board and the welding portion connected to the first circuit board are exposed to the first heat dissipation channel. Along the first direction, the first guide channel is located on one side of the battery cell assembly. The first guide channel connects the first heat dissipation channel and the second vent. The first guide member serves as at least a partial component for forming the first guide channel. The fan is connected to the shell. The fan is configured to pass the refrigerant through the first vent, the first heat dissipation channel, the first guide channel and the second vent.

[0005] The battery pack of the embodiment of the present application can circulate the refrigerant outside and inside the battery pack through the fan, the first vent, the first heat dissipation channel, the first guide channel and the second vent. The welding part and the first circuit board are exposed in the first heat dissipation channel. When the refrigerant flows through the first heat dissipation channel, the refrigerant can take away the heat generated by the welding part and the first circuit board to cool the welding part and the first circuit board, reduce the possibility of the first circuit board malfunctioning due to the excessive temperature of the welding part and the first circuit board, and help improve the safety of the battery pack.

[0006] In one or more optional embodiments above, the rear wall is used as a partial component to form the first flow guiding channel. The refrigerant flowing through the first flow guiding channel can directly contact the rear wall. The rear wall itself can dissipate heat, which is beneficial to improve the heat dissipation efficiency.

[0007] In one or more optional embodiments above, the rear wall and the first flow guide member form a first flow guide channel. The rear wall and the first flow guide member may contact each other to reduce leakage of the refrigerant from the first flow guide channel to the outside.

[0008] In one or more optional embodiments above, the battery pack includes a first buffer member located between the first flow guide and the battery cell assembly, and the first buffer member covers a side of the first flow guide close to the battery cell assembly. The first heat dissipation channel is located on one side of the battery cell assembly along the second direction, and the first direction is perpendicular to the second direction.

[0009] When the battery cell is in working state, the battery cell may expand. The first buffer member may provide expansion buffer space for the battery cell. When the battery cell expands, the battery cell may squeeze the first buffer member, and the first buffer member absorbs the expansion force by deformation, so as to reduce the possibility of excessive squeezing between the battery cells when the battery cell expands, and also reduce the possibility of the battery cell crushing the first flow guide member when the battery cell expands, which is beneficial to improve the safety of the battery pack.

[0010] In one or more of the above optional embodiments, the first buffer member has a first receiving groove facing the rear wall, and the first flow guide member is located in the first receiving groove.

[0011] The first buffer member covers the first flow guide member. The first buffer member can provide good protection for the first flow guide member, further reducing the possibility that the battery core will crush the first flow guide member when expansion occurs.

[0012] In one or more optional embodiments above, the first buffer member includes a first base, a first upper wall and a first lower wall, the first upper wall and the first lower wall are spaced apart along the third direction, the first upper wall and the first lower wall are both in contact with the rear wall, the first direction, the second direction and the third direction are perpendicular to each other, and at least a portion of the first flow guide member is located between the first upper wall and the first lower wall.

[0013] The first base covers the side of the first flow guide close to the battery core assembly. The first upper wall and the first lower wall are respectively in contact with the rear wall, which is beneficial to reduce the possibility of leakage of the refrigerant from between the first buffer and the rear wall, and is beneficial to improve the utilization rate of the refrigerant.

[0014] In one or more optional embodiments above, the battery cell housing includes a main body and at least one top seal portion, the electrode terminal extends from the top seal portion, and one top seal portion of each battery cell is exposed to the first heat dissipation channel. The first circuit board includes a plurality of openings and a plurality of conductive sheets, and at least one welding portion of each battery cell passes through one of the openings and is connected to one of the conductive sheets.

[0015] The refrigerant can dissipate heat to the back side of the first circuit board and other parts of the electrode terminal, which is beneficial to further improve the heat dissipation efficiency and enhance the heat dissipation effect.

[0016] In one or more optional embodiments above, the battery cell assembly includes a heat sink, which is located between two adjacent battery cells. The heat sink includes a hollow plate body and a phase change material filled in the hollow plate body, and the phase change material is exposed in the first heat dissipation channel.

[0017] When the battery cell assembly is in working state, the heat generated by the battery cell can be transferred to the hollow plate and the phase change material. The phase change material performs phase change heat storage and absorbs the heat generated by the battery cell, which is beneficial to reduce the possibility of overheating of the battery cell and improve the safety of the battery pack.

[0018] In one or more of the above optional embodiments, along the first direction, the projection of the first vent and the projection of the second vent are located on both sides of the projection of the first guide channel.

[0019] In one or more optional embodiments above, the peripheral side wall includes a right side wall and a left side wall spaced apart in the second direction, and a bottom wall and a top wall spaced apart in the third direction. The top wall connects the right side wall and the left side wall, and the bottom wall connects the right side wall and the left side wall.

[0020] In one or more of the above optional embodiments, the first circuit board is configured to collect parameters of the battery cell.

[0021] In one or more of the above optional embodiments, the refrigerant includes air.

[0022] In one or more of the above optional embodiments, the first buffer member includes an adhesive member provided on the first upper wall and the first lower wall, and the adhesive member bonds the first upper wall and the rear wall and bonds the first lower wall and the rear wall, which is beneficial to reduce the leakage of the refrigerant.

[0023] In one or more optional embodiments above, the battery pack includes a second heat dissipation channel and a second flow guide channel, the second heat dissipation channel is located between the peripheral side wall and the battery cell shell, in the second direction, the second heat dissipation channel and the first heat dissipation channel are respectively located on both sides of the battery cell assembly, the first direction is perpendicular to the second direction, the second heat dissipation channel is connected to the second vent, along the first direction, the second flow guide channel and the first flow guide channel are respectively located on both sides of the battery cell assembly, and the second flow guide channel is connected to the first vent and the second heat dissipation channel. The battery pack includes a second flow guide member, along the first direction, the battery cell assembly is located on one side of the second flow guide member, and the second flow guide member serves as at least a partial component for forming the second flow guide channel. The battery pack includes a second circuit board, a welding portion of one electrode terminal is welded to the first circuit board, and a welding portion of another electrode terminal is welded to the second circuit board. The second circuit board and the welding portion connected to the second circuit board are exposed in the second heat dissipation channel.

[0024] The second heat dissipation channel is configured as a space through which a coolant can pass. The welding portion of the second circuit board and the electrode terminal is exposed in the second heat dissipation channel. When the coolant flows through the second heat dissipation channel, the coolant can take away the heat generated by the welding portion and the second circuit board to cool the welding portion and the second circuit board, thereby reducing the possibility of the welding portion and the second circuit board being overheated.

[0025] In one or more of the above optional embodiments, the end wall serves as a partial component for forming the second flow guiding channel.

[0026] The refrigerant flowing through the second flow guide channel can directly contact the end wall. The end wall itself can dissipate heat, which is beneficial to improving the heat dissipation efficiency.

[0027] In one or more of the above optional embodiments, the end wall and the second flow guide member form a second flow guide channel.

[0028] The end wall can be in contact with the second flow guide member to reduce leakage of the refrigerant from the second flow guide channel to the outside.

[0029] In one or more of the above optional embodiments, the battery pack further includes a second buffer member, and the second buffer member is located between the second flow guide member and the battery cell assembly.

[0030] When the battery cell is in working state, it is possible that the battery cell will expand. The second buffer can provide expansion buffer space for the battery cell. When the battery cell expands, the battery cell can squeeze the second buffer, and the second buffer absorbs the expansion force by deformation, so as to reduce the possibility of excessive squeezing between the battery cells when the expansion occurs, and also reduce the possibility of the battery cell crushing the second flow guide when the expansion occurs, which is beneficial to improve the safety of the battery pack.

[0031] In one or more optional embodiments above, the second buffer member has a second receiving groove, the second receiving groove is arranged facing the end wall, and the second flow guide member is located in the second receiving groove.

[0032] The second buffer member covers the second flow guide member. The second buffer member can provide good protection for the second flow guide member, further reducing the possibility that the battery core will crush the second flow guide member when expansion occurs.

[0033] In one or more optional embodiments above, the second buffer member includes a second base, a second upper wall and a second lower wall. The second lower wall and the second upper wall are spaced apart along the third direction. The second upper wall and the second lower wall are both in contact with the end wall. At least part of the second flow guide member is located between the second upper wall and the second lower wall.

[0034] The second base covers the side of the second flow guide member close to the battery core assembly. The second upper wall and the second lower wall are respectively in contact with the end wall, which is beneficial to reduce the possibility of leakage of the refrigerant from between the second buffer member and the end wall, and is beneficial to improve the utilization rate of the refrigerant.

[0035] In one or more optional embodiments above, the second buffer member includes an adhesive member provided on the second upper wall and the second lower wall, and the adhesive member bonds the second upper wall and the end wall and bonds the second lower wall and the end wall, which is beneficial to reduce the leakage of the refrigerant.

[0036] In one or more optional embodiments above, the second flow guide is entirely located between the second upper wall and the second lower wall, so that the second buffer covers the entire second flow guide.

[0037] In one or more optional embodiments above, the battery cell housing includes a main body and two top seals, one top seal of each battery cell is exposed to the first heat dissipation channel, and the other top seal is exposed to the second heat dissipation channel. The second circuit board includes a plurality of openings and a plurality of conductive sheets, and a welding portion of each battery cell passes through one of the openings and is connected to one of the conductive sheets.

[0038] The coolant can dissipate heat on the back of the second circuit board and other parts of the electrode terminal, which is beneficial to further improve the heat dissipation efficiency and the heat dissipation effect. The coolant flowing through the second heat dissipation channel can dissipate heat on the welding part and the conductive sheet.

[0039] In one or more optional embodiments above, the battery pack includes an insulating sheet, which is disposed between the main body and the peripheral side wall, and the side edge of the main body is bonded to the insulating sheet.

[0040] There is no gap between the main body and the insulating sheet, so that the refrigerant will not flow between the main body and the insulating sheet, which is beneficial to improving the heat dissipation efficiency of the refrigerant to the welding part and the circuit board.

[0041] In one or more optional embodiments above, the battery pack includes a battery management circuit board and an end wall. Along the first direction, the battery management circuit board is located between the end wall and the front wall.

[0042] The battery management circuit board is separately arranged from the first circuit board. The battery management circuit board is provided with electronic components. The refrigerant does not contact the electronic components on the battery management circuit board, thereby reducing the possibility of the refrigerant adversely affecting the working state of the electronic components.

[0043] An embodiment of the present application provides an energy storage device, which includes the above-mentioned battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0045] Figure 1 is a schematic structural diagram of a battery pack provided in one embodiment of the present application;

[0046] Figure 2 is a schematic diagram of a partial cross-sectional structure of a battery pack provided in one embodiment of the present application;

[0047] Figure 3 is a schematic diagram of a partial exploded structure of a battery pack provided in one embodiment of the present application;

[0048] Figure 4 is a schematic diagram of the structure of a battery cell provided in one embodiment of the present application;

[0049] Figure 5 is a schematic diagram of a partial exploded structure of a battery pack provided in one embodiment of the present application;

[0050] Figure 6 is a partial structural schematic diagram of a battery pack provided in one embodiment of the present application;

[0051] Figure 7 yes Figure 6 The enlarged schematic diagram of the M in the middle;

[0052] Figure 8 yes Figure 5 The enlarged schematic diagram of P in the middle;

[0053] Fig. 9 is a schematic structural diagram of a heat sink provided by an embodiment of the present application;

[0054] Fig.10 yes Figure 6 Enlarged schematic diagram of point W in the middle.

[0055] Description of reference numerals:

[0056] 10. Battery pack;

[0057] 20. Shell; 21. Side wall; 211. Left side wall; 212. Right side wall; 213. Top wall; 214. Bottom wall; 22. Front wall; 221. First vent; 23. Rear wall; 231. Second vent; 24. End wall;

[0058] 30. Battery cell components;

[0059] 31. battery cell; 311. battery cell shell; 3111. main body; 3112. top seal; 312. electrode terminal; 3121. welding part;

[0060] 32. heat sink; 321. hollow plate; 322. phase change material;

[0061] 40. a first circuit board;

[0062] 50. A first heat dissipation channel;

[0063] 60. A first diversion channel;

[0064] 70. A first flow guide;

[0065] 80. Fan;

[0066] 90, first buffer member; 901, first receiving groove; 91, first base; 92, first upper wall; 93, first lower wall;

[0067] 110. Open your mouth;

[0068] 120. Conductive sheet;

[0069] 130. A second heat dissipation channel;

[0070] 140. Second diversion channel

[0071] 150, second flow guide;

[0072] 160. a second circuit board;

[0073] 170, second buffer member; 1701, second receiving groove; 171, second base; 172, second upper wall; 173, second lower wall;

[0074] 200. Battery management circuit board;

[0075] X, first direction;

[0076] Y, second direction;

[0077] Z. The third direction. DETAILED DESCRIPTION

[0078] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0079] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0080] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0081] In addition, the technical terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0082] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0083] See also Figures 1 to 4 As shown, the embodiment of the present application provides a battery pack 10 , which includes a housing 20 and a battery cell assembly 30 . The battery cell assembly 30 is located in the housing 20 .

[0084] In some achievable embodiments, the housing 20 includes a peripheral side wall 21 , a front wall 22 , and a rear wall 23 . The front wall 22 has a first vent 221 , and the rear wall 23 has a second vent 231 .

[0085] In some achievable embodiments, the peripheral side wall 21 is formed into a cylindrical structure. Two sides of the peripheral side wall 21 are respectively connected to the front wall 22 and the rear wall 23. Along the first direction X, the battery cell assembly 30 is located between the front wall 22 and the rear wall 23.

[0086] In some examples, the peripheral sidewall 21 includes a right sidewall 212 and a left sidewall 211 spaced apart along the second direction Y, and a bottom wall 214 and a top wall 213 spaced apart along the third direction Y. The top wall 213 connects the right sidewall 212 and the left sidewall 211, and the bottom wall 214 connects the right sidewall 212 and the left sidewall 211.

[0087] The battery cell assembly 30 includes a plurality of battery cells 31 . Each battery cell 31 includes a battery cell case 311 and two electrode terminals 312 , and each electrode terminal 312 includes a welding portion 3121 .

[0088] In some achievable embodiments, the battery cell 31 may be a soft-pack battery cell 31. The battery cell housing 311 includes an aluminum-plastic film.

[0089] In some achievable embodiments, the battery cell housing 311 includes a main body 3111 and at least one top seal 3112 connected to the main body 3111. Each electrode terminal 312 extends from the top seal 3112. The battery cell 31 includes an electrode assembly (not shown in the figure), which is disposed in the main body 3111. The electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator located between the positive electrode sheet and the negative electrode sheet.

[0090] In some possible implementations, see Figure 4 , Figure 6 and Figure 7 As shown, the cell housing 311 includes two top sealing portions 3112. Along the second direction Y, the two top sealing portions 3112 are respectively located on both sides of the main body 3111, and the two electrode terminals 312 extend from different top sealing portions 3112. In other embodiments, the cell housing 311 includes one top sealing portion 3112, and the two electrode terminals 312 extend from the same top sealing portion 3112.

[0091] In some achievable ways, at least one welding portion 3121 of each battery cell 31 is welded to the first circuit board 40. The welding portion 3121 is welded to the first circuit board 40. When the battery pack 10 is in operation, the welding portion 3121 and the first circuit board 40 themselves generate heat. The welding portion 3121 and the first circuit board 40 need to dissipate heat well so that the connection state between the welding portion 3121 and the first circuit board 40 is stable and the first circuit board 40 can work normally.

[0092] The first circuit board 40 is configured to collect parameters of the battery cell 31. The battery management system can monitor the operating status of the battery cell 31 through the first circuit board 40. For example, when the first circuit board 40 collects parameters of the battery cell 31 to indicate the possibility of thermal runaway of the battery cell 31, the battery management system can control the battery pack 10 to power off or perform firefighting and cooling treatment on the battery cell 31 to reduce the possibility of safety hazards in the battery pack 10 and improve the safety of the battery pack 10. In some examples, the first circuit board 40 is configured to collect parameters such as voltage and temperature of the battery cell 31. In some examples, the first circuit board 40 can be a printed circuit board (PCB).

[0093] In some achievable embodiments, the battery pack 10 includes a first heat dissipation channel 50, which is located between the peripheral side wall 21 and the battery cell housing 311. The first circuit board 40 and the welding portion 3121 connected to the first circuit board 40 are exposed in the first heat dissipation channel 50. The first heat dissipation channel 50 is configured as a space through which a refrigerant can pass. The first circuit board 40 and the electrode terminal 312 are exposed in the first heat dissipation channel 50. When the refrigerant flows through the first heat dissipation channel 50, the refrigerant can take away the heat generated by the welding portion 3121 and the first circuit board 40, dissipate the heat of the welding portion 3121 and the first circuit board 40, and reduce the possibility of the welding portion 3121 and the first circuit board 40 being overheated.

[0094] In some achievable embodiments, the battery pack 10 includes a first guide channel 60, and in the first direction X, the first guide channel 60 is located on one side of the battery cell assembly 30. The first guide channel 60 is connected to the first heat dissipation channel 50 and the second vent 231. The first guide channel 60 is configured as a space through which the refrigerant can pass. The first guide channel 60 can guide the refrigerant through the first heat dissipation channel 50 and the second vent 231 to improve the refrigerant transportation efficiency.

[0095] In some achievable embodiments, the battery pack 10 includes a first flow guide 70, and the first flow guide 70 is located on one side of the battery cell assembly 30 along the first direction X. The first flow guide 70 serves as at least a partial component forming the first flow guide channel 60. The first flow guide 70 serving as at least a partial component forming the first flow guide channel 60 means that the first flow guide 70 as a whole can serve as a component forming the first flow guide channel 60, or a part of the first flow guide 70 can serve as a component forming the first flow guide channel 60.

[0096] In some achievable embodiments, the battery pack 10 includes a fan 80, which is connected to the housing 20. The fan 80 is configured to pass the refrigerant of the battery pack 10 through the first vent 221, the first heat dissipation channel 50, the first guide channel 60, and the second vent 231. The fan 80 is configured to provide power to drive the refrigerant to flow, so that the refrigerant circulates outside the battery pack 10 and inside the battery pack 10, thereby improving the refrigerant transportation efficiency.

[0097] In some achievable ways, the first vent 221 can be used as a refrigerant inlet, and the second vent 231 can be used as a refrigerant outlet. Under the driving action of the fan 80, the refrigerant can flow through the first vent 221, the first heat dissipation channel 50, the first guide channel 60, and the second vent 231 in sequence.

[0098] In some achievable ways, the first vent 221 can be used as a refrigerant outlet. The second vent 231 can be used as a refrigerant inlet. Under the driving action of the fan 80, the refrigerant can flow through the second vent 231, the first guide channel 60, the first heat dissipation channel 50 and the second vent 231 in sequence. In some achievable ways, the fan 80 can be arranged at the first vent 221. Alternatively, the fan 80 can be arranged at the second vent 231.

[0099] The battery pack 10 of the embodiment of the present application can circulate the refrigerant outside the battery pack 10 and inside the battery pack 10 through the fan 80, the first vent 221, the first heat dissipation channel 50, the first guide channel 60 and the second vent 231. The welding part 3121 and the first circuit board 40 are exposed in the first heat dissipation channel 50. When the refrigerant flows through the first heat dissipation channel 50, the refrigerant can take away the heat generated by the welding part 3121 and the first circuit board 40 to cool the welding part 3121 and the first circuit board 40, reduce the possibility of the first circuit board 40 malfunctioning due to the excessive temperature of the welding part 3121 and the first circuit board 40, and help improve the safety of the battery pack 10.

[0100] In some embodiments, the refrigerant includes air.

[0101] In some practicable embodiments, the rear wall 23 is used as a partial component to form the first flow guiding channel 60. The refrigerant flowing through the first flow guiding channel 60 can directly contact the rear wall 23. The rear wall 23 itself can dissipate heat, which is beneficial to improve the heat dissipation efficiency.

[0102] In some examples, the rear wall 23 and the first guide 70 may contact each other, with no gap between them. In some examples, the rear wall 23 and the first guide 70 may not contact each other, with a small gap between them.

[0103] In some examples, the rear wall 23 and the first flow guide 70 form the first flow guide channel 60. The rear wall 23 and the first flow guide 70 each serve as a partial component forming the first flow guide channel 60. The rear wall 23 can contact the first flow guide 70 to reduce the leakage of the refrigerant from the first flow guide channel 60 to the outside.

[0104] In some possible implementations, see Figure 5 and Figure 6 As shown, the battery pack 10 includes a first buffer 90 located between the first guide 70 and the battery cell assembly 30. The first buffer 90 covers the side of the first guide 70 close to the battery cell assembly 30. The first heat dissipation channel 50 is located on one side of the battery cell assembly 30 along the second direction Y, and the first direction X is perpendicular to the second direction Y.

[0105] When the battery cell 31 is in working state, the battery cell 31 may expand. The first buffer member 90 may provide expansion buffer space for the battery cell 31. When the battery cell 31 expands, the battery cell 31 may squeeze the first buffer member 90. The first buffer member 90 absorbs the expansion force by deformation, so as to reduce the possibility of excessive squeezing between the battery cells 31 when expanding, and also reduce the possibility of the battery cell 31 crushing the first flow guide member 70 when expanding, which is beneficial to improve the safety of the battery pack 10.

[0106] In some examples, the first buffer member 90 may be foam. The first flow guide member 70 may be a metal member.

[0107] In some possible implementations, see Figure 5 As shown, the first buffer member 90 has a first receiving groove 901. The first receiving groove 901 is disposed facing the rear wall 23. The first flow guide member 70 is located in the first receiving groove 901.

[0108] The first buffer member 90 covers the first flow guide member 70. The first buffer member 90 can provide good protection for the first flow guide member 70, further reducing the possibility that the battery cell 31 may crush the first flow guide member 70 when it expands.

[0109] In some possible implementations, see Figure 5 As shown, the first buffer member 90 includes a first base 91, a first upper wall 92 and a first lower wall 93. The first lower wall 93 and the first upper wall 92 are spaced apart along the third direction Z. The first upper wall 92 and the first lower wall 93 are both in contact with the rear wall 23. At least a portion of the first flow guide member 70 is located between the first upper wall 92 and the first lower wall 93. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0110] The first base 91 covers the side of the first flow guide 70 close to the battery cell assembly 30. The first upper wall 92 and the first lower wall 93 are respectively in contact with the rear wall 23, which is conducive to reducing the possibility of leakage of the refrigerant from between the first buffer 90 and the rear wall 23, and is conducive to improving the utilization rate of the refrigerant.

[0111] In some examples, the first buffer member 90 includes an adhesive member (not shown) provided on the first upper wall 92 and the first lower wall 93 , and the adhesive member bonds the first upper wall 92 and the rear wall 23 and bonds the first lower wall 93 and the rear wall 23 , which helps to reduce leakage of the refrigerant.

[0112] In some examples, the first air guide 70 is entirely located between the first upper wall 92 and the first lower wall 93 , so that the first buffer 90 covers the entire first air guide 70 .

[0113] In some achievable ways, a top seal portion 3112 of each battery cell 31 is exposed to the first heat dissipation channel 50. The top seal portion 3112 and the first circuit board 40 are arranged at intervals, and the back side of the first circuit board 40 is exposed to the first heat dissipation channel 50. The refrigerant can dissipate heat from the back side of the first circuit board 40 and other parts of the electrode terminal 312, which is conducive to further improving the heat dissipation efficiency and the heat dissipation effect. Among them, the back side of the first circuit board 40 refers to the surface of the first circuit board 40 close to the main body 3111.

[0114] In some achievable embodiments, the first circuit board 40 includes a plurality of openings 110 and a plurality of conductive sheets 120. At least one welding portion 3121 of each battery cell 31 passes through one of the openings 110 and is connected to one of the conductive sheets 120. The coolant flowing through the first heat dissipation channel 50 can dissipate heat from the welding portion 3121 and the conductive sheet 120. For example, the welding portion 3121 is welded to the conductive sheet 120.

[0115] For some examples, see Figure 8 As shown, one of the welding portions 3121 of each battery cell 31 passes through one of the openings 110 to be connected to one of the conductive sheets 120. In other embodiments, two welding portions 3121 of each battery cell 31 pass through at least one of the openings 110 to be connected to different conductive sheets 120. For example, two welding portions 3121 of each battery cell 31 pass through the same opening 110, or two welding portions 3121 of each battery cell 31 pass through different openings 110.

[0116] In some possible implementations, see Figure 8 and Fig. 9 As shown, the battery cell assembly 30 includes a heat sink 32. The heat sink 32 is located between two adjacent battery cells 31. The heat sink 32 includes a hollow plate 321 and a phase change material 322 filled in the hollow plate 321. The phase change material 322 is exposed in the first heat dissipation channel 50. The first heat dissipation channel 50 dissipates heat from the phase change material 322.

[0117] When the battery cell assembly 30 is in operation, the heat generated by the battery cell 31 can be transferred to the hollow plate 321 and the phase change material 322. The phase change material 322 performs phase change heat storage and absorbs the heat generated by the battery cell 31, which is beneficial to reduce the possibility of the battery cell 31 being overheated and improve the safety of the battery pack 10.

[0118] In some possible implementations, see Figures 2 to 6 , Fig.10As shown, the battery pack 10 includes a second heat dissipation channel 130 and a second guide channel 140. The second heat dissipation channel 130 is located between the peripheral side wall 21 and the battery cell housing 311. Along the second direction Y, the second heat dissipation channel 130 and the first heat dissipation channel 50 are respectively located on both sides of the battery cell assembly 30. The second heat dissipation channel 130 is connected to the second vent 231. Along the first direction X, the second guide channel 140 and the first guide channel 60 are respectively located on both sides of the battery cell assembly 30. The second guide channel 140 is connected to the first vent 221 and the second heat dissipation channel 130.

[0119] In some achievable embodiments, the cell housing 311 includes two top seals 3112, and along the second direction Y, the two top seals 3112 are respectively located on both sides of the main body 3111, and the two electrode terminals 312 extend from different top seals 3112. The battery pack 10 includes a second circuit board 160. The welding portion 3121 of one electrode terminal 312 is welded to the first circuit board 40, and the welding portion 3121 of the other electrode terminal 312 is welded to the second circuit board 160. The second circuit board 160 and the welding portion 3121 connected to the second circuit board 160 are exposed in the second heat dissipation channel 130.

[0120] The second circuit board 160 is configured to collect parameters of the battery cell 31. The battery management system can monitor the operating status of the battery cell 31 through the second circuit board 160. For example, when the second circuit board 160 collects parameters of the battery cell 31 to indicate the possibility of thermal runaway of the battery cell 31, the battery management system can control the battery pack 10 to power off or perform firefighting cooling and fire extinguishing treatment on the battery cell 31 to reduce the possibility of safety hazards in the battery pack 10 and improve the safety of the battery pack 10. In some examples, the second circuit board 160 is configured to collect parameters such as voltage and temperature of the battery cell 31. In some examples, the second circuit board 160 can be a printed circuit board (PCB).

[0121] The soldering portion 3121 and the second circuit board 160 need to dissipate heat well so that the connection between the soldering portion 3121 and the second circuit board 160 is stable and the second circuit board 160 can work normally.

[0122] The second heat dissipation channel 130 is configured as a space through which the refrigerant can pass. The second circuit board 160 and the welding portion 3121 are exposed in the second heat dissipation channel 130. When the refrigerant flows through the second heat dissipation channel 130, the refrigerant can take away the heat generated by the welding portion 3121 and the second circuit board 160 to cool the welding portion 3121 and the second circuit board 160, thereby reducing the possibility of the welding portion 3121 and the second circuit board 160 being overheated.

[0123] The second guide channel 140 is configured as a space through which the refrigerant can pass. The second guide channel 140 can guide the refrigerant to flow between the second heat dissipation channel 130 and the first vent 221. The second guide channel 140 can guide the refrigerant through the second heat dissipation channel 130 and the second vent 231 to improve the refrigerant transportation efficiency.

[0124] In some achievable embodiments, the battery pack 10 includes a second flow guide 150. Along the first direction X, the battery cell assembly 30 is located on one side of the second flow guide 150. The second flow guide 150 serves as at least a partial component forming the second flow guide channel 140. Along the first direction X, the second flow guide 150 and the first flow guide 70 are located on both sides of the battery cell assembly 30. The second flow guide 150 serving as at least a partial component forming the second flow guide channel 140 means that the second flow guide 150 as a whole can serve as a component forming the second flow guide channel 140, or a part of the second flow guide 150 can serve as a component forming the second flow guide channel 140.

[0125] The fan 80 is configured to pass the refrigerant outside the battery pack 10 through the first vent 221 , the first heat dissipation channel 50 , the second heat dissipation channel 130 , the first guide channel 60 , the second guide channel 140 and the second vent 231 .

[0126] In some achievable embodiments, the end wall 24 of the housing 20 is used as a partial component to form the second flow guiding channel 140. The refrigerant flowing through the second flow guiding channel 140 can directly contact the end wall 24. The end wall 24 itself can dissipate heat, which is beneficial to improve the heat dissipation efficiency.

[0127] In some examples, the end wall 24 and the second flow guide 150 form the second flow guide channel 140. The end wall 24 and the second flow guide 150 each serve as a partial component forming the second flow guide channel 140. The end wall 24 can contact the second flow guide 150 to reduce the leakage of the refrigerant from the second flow guide channel 140 to the outside.

[0128] For some examples, see Figure 5 and Figure 6 As shown, the battery pack 10 further includes a second buffer 170. The second buffer 170 is located between the second flow guide 150 and the battery cell assembly 30. The second buffer 170 covers the side of the second flow guide 150 close to the battery cell assembly 30.

[0129] When the battery cell 31 is in working state, the battery cell 31 may expand. The second buffer 170 may provide expansion buffer space for the battery cell 31. When the battery cell 31 expands, the battery cell 31 may squeeze the second buffer 170, and the second buffer 170 absorbs the expansion force by deformation, so as to reduce the possibility of excessive squeezing between the battery cells 31 when expanding, and also reduce the possibility of the battery cell 31 crushing the second guide member 150 when expanding, which is beneficial to improve the safety of the battery pack 10.

[0130] In some examples, the second buffer member 170 may be foam. The second flow guide member 150 may be a metal member.

[0131] In some achievable embodiments, the second buffer member 170 has a second receiving groove 1701 . The second receiving groove 1701 is disposed facing the end wall 24 . The second flow guide member 150 is located in the second receiving groove 1701 .

[0132] The second buffer 170 covers the second flow guide 150. The second buffer 170 can provide good protection for the second flow guide 150, further reducing the possibility that the battery cell 31 will crush the second flow guide 150 when it expands.

[0133] In some achievable embodiments, the second buffer member 170 includes a second base 171, a second upper wall 172, and a second lower wall 173. The second lower wall 173 and the second upper wall 172 are spaced apart from each other along the third direction Z. The second upper wall 172 and the second lower wall 173 are both in contact with the end wall 24. At least a portion of the second flow guide member 150 is located between the second upper wall 172 and the second lower wall 173.

[0134] The second base 171 covers the side of the second flow guide 150 close to the battery cell assembly 30. The second upper wall 172 and the second lower wall 173 are respectively in contact with the end wall 24, which is conducive to reducing the possibility of leakage of the refrigerant from between the second buffer 170 and the end wall 24, and is conducive to improving the utilization rate of the refrigerant.

[0135] In some examples, the second buffer member 170 includes an adhesive member (not shown) disposed on the second upper wall 172 and the second lower wall 173 , the adhesive member bonds the second upper wall 172 and the end wall 24 and bonds the second lower wall 173 and the end wall 24 , which helps to reduce leakage of the refrigerant.

[0136] In some examples, the second air guide 150 is entirely located between the second upper wall 172 and the second lower wall 173 , so that the second buffer 170 covers the entire second air guide 150 .

[0137] In some possible implementations, see Figure 4 and Fig.10As shown, the battery cell housing 311 includes a main body 3111 and two top seals 3112. One top seal 3112 of each battery cell 31 is exposed to the first heat dissipation channel 50, and the other top seal 3112 is exposed to the second heat dissipation channel 130. The top seal 3112 and the second circuit board 160 are arranged at intervals, and the back of the second circuit board 160 is exposed to the second heat dissipation channel 130. The refrigerant can dissipate heat to the back of the second circuit board 160 and other parts of the electrode terminal 312, which is conducive to further improving the heat dissipation efficiency and enhancing the heat dissipation effect. Among them, the back of the second circuit board 160 refers to the surface of the second circuit board 160 close to the main body 3111.

[0138] In some examples, the second circuit board 160 includes a plurality of openings 110 and a plurality of conductive sheets 120. A welding portion 3121 of each battery cell 31 passes through one of the openings 110 and is connected to one of the conductive sheets 120. The coolant flowing through the second heat dissipation channel 130 can dissipate heat from the welding portion 3121 and the conductive sheet 120.

[0139] In some achievable embodiments, the phase change material 322 is exposed in the second heat dissipation channel 130 . The second heat dissipation channel 130 dissipates heat from the phase change material 322 .

[0140] In some possible implementations, see Figure 3 As shown, the battery pack 10 includes a battery management circuit board 200 and an end wall 24. Along the first direction X, the battery management circuit board 200 is located between the front wall 22 and the end wall 24.

[0141] The battery management circuit board 200 is separately arranged from the first circuit board 40. Electronic components are arranged on the battery management circuit board 200. The refrigerant does not contact the electronic components on the battery management circuit board 200, thereby reducing the possibility of the refrigerant adversely affecting the working state of the electronic components.

[0142] In some achievable embodiments, along the first direction X, the projection of the first vent 221 and the projection of the second vent 231 are located on both sides of the projection of the first guide channel 60 , which is beneficial to the flow of the refrigerant.

[0143] According to some embodiments of the present application, an energy storage device is further provided, comprising a battery pack 10 according to any of the above schemes, and the battery pack 10 is used to provide electrical energy to the energy storage device.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery pack, characterized in that: include: The housing comprises a peripheral side wall, a front wall and a rear wall spaced apart along a first direction, wherein the front wall has a first vent and the rear wall has a second vent; A battery cell assembly, comprising a plurality of battery cells, each of the battery cells comprising a battery cell housing and two electrode terminals, each of the electrode terminals comprising a welding portion; a first circuit board, wherein at least one welding portion of each of the battery cells is connected to the first circuit board; A first heat dissipation channel is located between the peripheral side wall and the battery cell housing, and the first circuit board and the welding portion connected to the first circuit board are exposed in the first heat dissipation channel; A first guide channel, along the first direction, the first guide channel is located on one side of the battery core assembly, and the first guide channel is connected to the first heat dissipation channel and the second vent; a first flow guide member, the first flow guide member serving as at least a partial component forming the first flow guide channel; A fan is connected to the housing, and the fan is configured to pass the refrigerant through the first vent, the first heat dissipation channel, the first guide channel and the second vent.

2. The battery pack according to claim 1, characterized in that: The rear wall serves as a partial component for forming the first flow guiding channel.

3. The battery pack according to claim 2, characterized in that: The rear wall and the first flow guide member form the first flow guide channel.

4. The battery pack according to any one of claims 1 to 3, characterized in that: The battery pack includes a first buffer member located between the first flow guide member and the battery cell assembly, wherein the first buffer member covers a side surface of the first flow guide member close to the battery cell assembly; The first heat dissipation channel is located on one side of the battery core assembly along a second direction, and the first direction is perpendicular to the second direction.

5. The battery pack according to claim 4, characterized in that: The first buffer member has a first receiving groove facing the rear wall, and the first flow guide member is located in the first receiving groove.

6. The battery pack according to claim 4 or 5, characterized in that: The first buffer member includes a first base, a first upper wall and a first lower wall, the first upper wall and the first lower wall are spaced apart along a third direction, the first upper wall and the first lower wall are both in contact with the rear wall, and the first direction, the second direction and the third direction are perpendicular to each other; At least a portion of the first flow guide is located between the first upper wall and the first lower wall.

7. The battery pack according to any one of claims 1 to 6, characterized in that: The battery cell housing comprises a main body and at least one top sealing portion, the electrode terminal extends from the top sealing portion, and one top sealing portion of each battery cell is exposed to the first heat dissipation channel; The first circuit board includes a plurality of openings and a plurality of conductive sheets, and at least one welding portion of each of the battery cells passes through one of the openings and is connected to one of the conductive sheets.

8. The battery pack according to claim 7, characterized in that: The battery core assembly includes a heat sink, which is located between two adjacent battery cores. The heat sink includes a hollow plate body and a phase change material filled in the hollow plate body, and the phase change material is exposed in the first heat dissipation channel.

9. The battery pack according to any one of claims 1 to 8, characterized in that: Along the first direction, a projection of the first vent and a projection of the second vent are located on both sides of a projection of the first guide channel.

10. An energy storage device, characterized in that: A battery pack comprising the battery pack according to any one of claims 1 to 9.

Images