Battery pack and energy storage device

Abstract

The invention discloses a battery pack and an energy storage device. The battery pack comprises a shell, N battery cells arranged in the first direction, first heat-conducting glue, a first heating piece, a second heating piece and a heat dissipation piece. The housing includes a bottom wall. The N battery cells are located in the shell and arranged on the bottom wall. N is an integer greater than or equal to 5, and along the first direction, the N battery cells comprise a first battery cell and an Nth battery cell which are positioned on the outermost side, a second battery cell and an (N-1) th battery cell, and a middle battery cell positioned between the second battery cell and the (N-1) th battery cell. The first heat-conducting glue is connected with the middle battery cell and the bottom wall; the first heating piece is connected with the first battery cell, and the first heating piece is configured to heat the first battery cell; the second heating piece is connected with the Nth battery cell, and the second heating piece is configured to heat the Nth battery cell. The heat dissipation piece is located on the side, away from the battery cells, of the bottom wall, and the heat dissipation piece is configured to dissipate heat of the middle battery cell.

Description

Technical Field

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

[0002] With the continuous updating and development of battery technology, the application areas of batteries are also expanding. The resulting battery safety issues are receiving more and more public attention. When the battery is in use, due to the difference in heat generation during charging and discharging and the difference in heat dissipation environment of each battery cell in the battery, there is a temperature difference between the cells, increasing safety risks. Summary of the invention

[0003] In view of this, it is necessary to provide a battery pack and an energy storage device that can reduce the temperature difference between battery cells and improve safety.

[0004] An embodiment of the present application provides a battery pack, comprising a shell, N battery cells arranged along a first direction, a first thermally conductive adhesive, a first heating element, a second heating element and a heat sink. The shell comprises a bottom wall. The N battery cells are located in the shell and are arranged on the bottom wall. N is an integer greater than or equal to 5. Along the first direction, the N battery cells include a first battery cell and an Nth battery cell located on the outermost sides, a second battery cell and an N-1th battery cell, and an intermediate battery cell located between the second battery cell and the N-1th battery cell. The first thermally conductive adhesive connects the intermediate battery cell and the bottom wall. The first heating element is connected to the first battery cell, and the first heating element is configured to heat the first battery cell. The second heating element is connected to the Nth battery cell, and the second heating element is configured to heat the Nth battery cell. The heat sink is located on the side of the bottom wall away from the battery cell, and the heat sink is configured to dissipate heat from the intermediate battery cell. The middle battery cell is surrounded by adjacent battery cells, and the heat is mainly transferred to the outside through the first thermally conductive adhesive. The heat dissipation path is long. The present application transfers the heat of the middle battery cell to the bottom wall through the first thermally conductive adhesive, and dissipates the heat of the middle battery cell through the heat dissipation element, thereby improving the heat dissipation efficiency of the middle battery cell. The first battery cell and the Nth battery cell are located on the outermost side, and the heat dissipates faster than the middle battery cell. There is a temperature difference between the middle battery cell and the first battery cell, and there is a temperature difference between the middle battery cell and the Nth battery cell. The first heating element heats the first battery cell, and the second heating element heats the Nth battery cell, thereby reducing the temperature difference between the outermost battery cell and the middle battery cell, thereby improving safety.

[0005] In one or more optional embodiments above, the heat sink includes a heat sink fin, and the heat sink fin is connected to the bottom wall. Along the second direction, the bottom wall is located above the heat sink fin, the heat sink fin is separated from the first battery cell, and the heat sink fin is separated from the Nth battery cell, and the second direction is perpendicular to the first direction. When the heat sink dissipates heat to the middle battery cell, the heat dissipation effect of the heat sink on the first battery cell and the Nth battery cell can be reduced, which is conducive to reducing the temperature difference between the first battery cell and the middle battery cell and reducing the temperature difference between the Nth battery cell and the middle battery cell.

[0006] In one or more of the above optional embodiments, the heat dissipation fins are provided with heat dissipation channels. The battery pack includes an air inlet channel located below the first battery cell and an air outlet channel located below the Nth battery cell. The air inlet channel is communicated with the heat dissipation channel, and the air outlet channel is communicated with the heat dissipation channel. This is beneficial for guiding the airflow blown by the fan, reducing the airflow backflow, and the airflow blown by the fan can also dissipate heat from the first battery cell, the second battery cell, the (N - 1)th battery cell, and the Nth battery cell, which is beneficial for reducing the temperature difference between the N battery cells.

[0007] In one or more of the above optional embodiments, the battery pack includes an insulating member, and the insulating member connects the first thermal conductive adhesive to the bottom wall. Each battery cell includes a battery cell housing. Along the second direction, the projection of each battery cell housing is located within the projection of the insulating member. The first thermal conductive adhesive bonds the insulating member and the battery cell housing of the middle battery cell. Through the insulating member, the risk of short circuit caused by the contact between the metal layer in the battery cell housing and the bottom wall is reduced.

[0008] In one or more of the above optional embodiments, the thermal conductivity of the first thermal conductive adhesive is 0.8 W / (m·K) - 2 W / (m·K), which is beneficial for improving the heat dissipation effect of the middle battery cell and reducing the temperature difference between the outermost battery cell and the middle battery cell.

[0009] In one or more of the above optional embodiments, the battery pack includes a first end plate. Along the first direction, the first battery cell includes a first wall located on the outermost side. The first heating member is connected to the first wall, and a first heat insulation member is provided between the first end plate and the first heating member. The thermal conductivity of the first heat insulation member is less than 0.5 W / (m·K). When the first heating member heats the first battery cell, through the first heat insulation member, the heat loss of the first battery cell is slowed down, and part of the heat of the first battery cell can be transferred to the second battery cell. When the first battery cell dissipates heat, the first heat insulation member can slow down the heat dissipation speed, which is beneficial for reducing the temperature difference between the outermost battery cell and the middle battery cell.

[0010] In one or more of the above optional embodiments, the battery pack includes a second end plate. Along the first direction, the Nth battery cell includes a second wall located on the outermost side. The second heating member is connected to the second wall, and a second heat insulation member is provided between the second end plate and the second heating member. The thermal conductivity of the second heat insulation member is less than 0.5 W / (m·K). When the second heating member heats the Nth battery cell, through the second heat insulation member, the heat loss of the Nth battery cell is slowed down, and part of the heat of the Nth battery cell can be transferred to the (N - 1)th battery cell. When the Nth battery cell dissipates heat, the second heat insulation member can slow down the heat dissipation speed, which is beneficial for reducing the temperature difference between the outermost battery cell and the middle battery cell.

[0011] In one or more of the above optional embodiments, the battery pack includes a first temperature detector, a second temperature detector, and a third temperature detector. The first temperature detector detects the temperature of the first battery cell, the second temperature detector detects the temperature of the Nth battery cell, and the third temperature detector detects the temperature of the intermediate battery cell. When the heat dissipating member dissipates heat from the intermediate battery cell and the temperature difference between the first battery cell and the intermediate battery cell is greater than the first threshold, the first heating member heats the first battery cell, which helps to reduce the temperature difference between the first battery cell 201 and the intermediate battery cell 205. When the heat dissipating member dissipates heat from the intermediate battery cell and the temperature difference between the Nth battery cell and the intermediate battery cell is greater than the second threshold, the second heating member heats the Nth battery cell, which helps to reduce the temperature difference between the Nth battery cell and the intermediate battery cell.

[0012] In one or more of the above optional embodiments, the first threshold is greater than 3°C and the second threshold is greater than 3°C.

[0013] In one or more of the above optional embodiments, along the third direction, bending portions are provided on both sides of the bottom wall, and the heat dissipation fins are arranged along the third direction between the two bending portions. The battery pack includes a first flow guide member, and along the second direction, the first flow guide member overlaps with the first battery cell. The first flow guide member connects the two bending portions, and the first flow guide member and the bottom wall form an air inlet channel.

[0014] In one or more of the above optional embodiments, along the second direction, a part of the heat dissipation fins is located between the bottom wall and the first flow guide member, which is convenient for fixing the heat dissipation fins.

[0015] In one or more of the above optional embodiments, the battery pack includes a second flow guide member, and along the second direction, the second flow guide member overlaps with the Nth battery cell. The second flow guide member connects the two bending portions, and the second flow guide member and the bottom wall form an air outlet channel.

[0016] In one or more of the above optional embodiments, along the second direction, a part of the heat dissipation fins is located between the bottom wall and the second flow guide member, which is convenient for fixing the heat dissipation fins.

[0017] An embodiment of the present application provides an energy storage device, including a cabinet body, a plurality of battery packs arranged along the second direction in any one of the above embodiments, and a fan. The cabinet body includes a first door body and a second door body. The first door body is provided with an air inlet, and the second door body is provided with an air outlet. The plurality of battery packs are arranged in the cabinet body. The fan is configured to blow air towards the heat dissipating member.

[0018] The above energy storage device transfers the heat of the middle battery cell to the bottom wall through the first thermal conductive adhesive, and dissipates the heat of the middle battery cell through the heat dissipation component, improving the heat dissipation efficiency of the middle battery cell. The first battery cell and the Nth battery cell are located on the outermost side, and the heat dissipates faster than that of the middle battery cell. There is a temperature difference between the middle battery cell and the first battery cell, and there is also a temperature difference between the middle battery cell and the Nth battery cell. The first heating component heats the first battery cell, and the second heating component heats the Nth battery cell, reducing the temperature difference between the outermost battery cells and the middle battery cell and improving safety. Brief Description of the Drawings

[0019] Figure 1 Shows a schematic structural diagram of a battery pack in some embodiments.

[0020] Figure 2 Shows an exploded schematic diagram of a battery pack in some embodiments.

[0021] Figure 3 Shows a schematic structural diagram of a part of a battery pack in some embodiments.

[0022] Figure 4 Shows a partial schematic structural diagram of a battery pack in some embodiments.

[0023] Figure 5 Shows a schematic structural diagram of a battery cell in some embodiments.

[0024] Figure 6 Shows a schematic structural diagram of a battery pack from another perspective in some embodiments.

[0025] Figure 7 Shows Figure 6 an exploded schematic diagram of the battery pack in

[0026] Figure 8 Shows a partial schematic structural diagram of a battery pack in some embodiments.

[0027] Figure 9 Shows a partial schematic structural diagram of a battery pack in some embodiments.

[0028] Figure 10 Shows a schematic structural diagram of an energy storage device in some embodiments.

[0029] Figure 11 Shows a schematic structural diagram of an energy storage device from another perspective in some embodiments.

[0030] Figure 12 Shows a partial schematic structural diagram of an energy storage device in some embodiments.

[0031] Description of the Main Component Symbols: Battery Pack 100 Housing 10 Bottom Wall 11 Bending part 111 Top wall 12 First side wall 13 Second side wall 14 Third side wall 15 Fourth side wall 16 Electric core 20 First electric core 201 First wall 2011 Nth electric core 202 Second wall 2021 Second electric core 203 (N - 1)th electric core 204 Intermediate electric core 205 Electric core housing 21 Fifth side wall 211 Sixth side wall 212 Electrode terminal 22 First thermal conductive adhesive 30 First heating element 40 Second heating element 50 Heat dissipation component 60 Heat dissipation fin 61 Heat dissipation channel 611 Second thermal conductive adhesive 70 Insulating component 80 Air inlet channel 101 Air outlet channel 102 First flow guiding component 103 Second flow guiding component 104 Fixing component 105 First end plate 106 Second end plate 107 First circuit board 108 Second circuit board 109 First heat preservation component 110 Second heat preservation component 120 First temperature detection component 130 Second temperature detection component 140 Third temperature detection component 150 Wire 160 Second circuit board 109 Energy storage device 200 Cabinet 210 First door 210A Second door 210B Air inlet 2101 Air outlet 2102 Fan 220 First direction X Second direction Y Third direction Z The following specific embodiments will further illustrate the present application in conjunction with the above-mentioned drawings. Specific embodiments

[0032] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments.

[0033] When a component is considered to be "provided on" another component, it may be directly provided on the other component or there may be an intermediate component at the same time. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be an intermediate component at the same time.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "or / and" used herein includes any and all combinations of one or more of the related listed items.

[0035] It can be understood that the term "vertical" is used to describe the ideal state between two components. In the actual production or use state, there may be a state approximately vertical or equal between two components. For example, in combination with numerical descriptions, vertical can refer to the included angle range between two straight lines being between 90°±10°, vertical can also refer to the dihedral angle range between two planes being between 90°±10°, and vertical can also refer to the included angle range between a straight line and a plane being between 90°±10°. The two components described as "vertical" may not be absolute straight lines or planes, and may also be approximately straight lines or planes. From a macroscopic perspective, as long as the overall extension direction is a straight line or a plane, the components can be considered as "straight lines" or "planes".

[0036] The term "parallel" is used to describe the ideal state between two components. In the actual production or use state, there can be a state approximate to parallel between two components. For example, in combination with numerical description, parallel can refer to the included angle range between two straight lines being within 180° ± 10°, parallel can also refer to the dihedral angle range between two planes being within 180° ± 10°, and parallel can further refer to the included angle range between a straight line and a plane being within 180° ± 10°. The two components described as "parallel" may not be absolute straight lines or planes, and can also be approximately straight lines or planes. From a macroscopic perspective, as long as the overall extension direction is a straight line or a plane, the components can be considered as "straight lines" or "planes".

[0037] Unless otherwise defined, the term "a plurality of" in this article, when used to describe the quantity of components, specifically refers to two or more of such components.

[0038] The following will describe in detail some embodiments of the present application with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0039] Please refer to Figures 1 to 4 , an embodiment of the present application provides a battery pack 100, including a housing 10 and N battery cells 20 arranged along a first direction X. The housing 10 includes a bottom wall 11, and the N battery cells 20 are located inside the housing 10 and are disposed on the bottom wall 11.

[0040] In some embodiments, N is an integer greater than or equal to 5. Along the first direction X, the N battery cells 20 include a first battery cell 201 and an Nth battery cell 202 located on the outermost sides, a second battery cell 203 and an (N - 1)th battery cell 204 located on the second outermost sides, and an intermediate battery cell 205 located between the second battery cell 203 and the (N - 1)th battery cell 204.

[0041] In some embodiments, along the first direction X, the first battery cell 201 is adjacent to the second battery cell 203, and the (N - 1)th battery cell 204 is adjacent to the Nth battery cell 202. The number of intermediate battery cells 205 can be one or more.

[0042] For example, when N is equal to 5, along the first direction X, the first battery cell is the first battery cell 20, the fifth battery cell is the Nth battery cell, the second battery cell is the second battery cell 203, the fourth battery cell is the (N - 1)th battery cell 204, and the third battery cell is the intermediate battery cell 205.

[0043] For example, when N is equal to 6, along the first direction X, the first battery cell is the first battery cell 20, the sixth battery cell is the Nth battery cell, the second battery cell is the second battery cell 203, the fifth battery cell is the (N - 1)th battery cell 204, and the third battery cell and the fourth battery cell are the intermediate battery cells 205.

[0044] In some embodiments, the battery pack 100 includes a first thermal conductive adhesive 30, and the first thermal conductive adhesive 30 connects the intermediate battery cell 205 and the bottom wall 11. The first thermal conductive adhesive 30 conducts the heat of the intermediate battery cell 205 to the bottom wall 11.

[0045] In some embodiments, the battery pack 100 includes a first heating element 40, and the first heating element 40 connects to the first battery cell 201. The first heating element 40 is configured to heat the first battery cell 201.

[0046] In some embodiments, the battery pack 100 includes a second heating element 50, and the second heating element 50 connects to the Nth battery cell 202. The second heating element 50 is configured to heat the Nth battery cell 202.

[0047] In some embodiments, the battery pack 100 includes a heat dissipation element 60, and the heat dissipation element 60 is located on the side of the bottom wall 11 away from the battery cells 20. The heat dissipation element 60 is configured to dissipate heat from the intermediate battery cell 205. Herein, the heat dissipation element 60 dissipating heat from the intermediate battery cell 205 means that the intermediate battery cell 205 transfers heat to the bottom wall 11 through the first thermal conductive adhesive 30, transfers heat to the heat dissipation element 60 through the bottom wall 11, and transfers heat to the outside through the heat dissipation element 60.

[0048] The intermediate battery cell 205 is surrounded by adjacent battery cells, and heat is mainly transferred to the outside through the first thermal conductive adhesive 30, with a long heat dissipation path. In this application, the heat of the intermediate battery cell 205 is transferred to the bottom wall 11 through the first thermal conductive adhesive 30, and the heat dissipation element 60 dissipates heat from the intermediate battery cell 205, improving the heat dissipation efficiency of the intermediate battery cell 205. The first battery cell 201 and the Nth battery cell 202 are located on the outermost side, and heat dissipates faster than the intermediate battery cell 205. There is a temperature difference between the intermediate battery cell 205 and the first battery cell 201, and there is a temperature difference between the intermediate battery cell 205 and the Nth battery cell 202. By heating the first battery cell 201 with the first heating element 40 and heating the Nth battery cell 202 with the second heating element 50, the temperature difference between the outermost battery cells and the intermediate battery cell 205 is reduced, improving safety.

[0049] Please refer to Figure 2 In some embodiments, the housing 10 includes a top wall 12, and the bottom wall 11 and the top wall 12 are arranged along the second direction Y. The first direction X is perpendicular to the second direction Y. The battery pack 100 includes a second thermal conductive adhesive 70, and the second thermal conductive adhesive 70 connects the intermediate battery cell 205 and the top wall 12. Part of the heat of the intermediate battery cell 205 is transferred to the top wall 12 through the second thermal conductive adhesive 70 and transferred from the top wall 12 to the outside of the battery pack 100.

[0050] In some embodiments, the thermal conductivity of the first thermal conductive adhesive 30 is 0.8 W / (m·K) - 2 W / (m·K), which is beneficial to improving the heat dissipation effect of the intermediate battery cell 205 and reducing the temperature difference between the outermost battery cells and the intermediate battery cell 205.

[0051] Optionally, the thermal conductivity of the first thermal conductive adhesive 30 can be any value within the range composed of any one or any two of 0.8 W / (m·K), 0.9 W / (m·K), 1 W / (m·K), 1.1 W / (m·K), 1.2 W / (m·K), 1.3 W / (m·K), 1.4 W / (m·K), 1.5 W / (m·K), 1.6 W / (m·K), 1.7 W / (m·K), 1.8 W / (m·K), 1.9 W / (m·K), 2 W / (m·K).

[0052] In some embodiments, the thermal conductivity of the second thermal conductive adhesive 70 is 0.8 W / (m·K) - 2 W / (m·K), which is beneficial to improving the heat dissipation effect of the middle battery cell 205 and reducing the temperature difference between the outermost battery cell and the middle battery cell 205. Optionally, the thermal conductivity of the second thermal conductive adhesive 70 can be any value within the range composed of any one or any two of 0.8 W / (m·K), 0.9 W / (m·K), 1 W / (m·K), 1.1 W / (m·K), 1.2 W / (m·K), 1.3 W / (m·K), 1.4 W / (m·K), 1.5 W / (m·K), 1.6 W / (m·K), 1.7 W / (m·K), 1.8 W / (m·K), 1.9 W / (m·K), 2 W / (m·K).

[0053] In some embodiments, the housing 10 includes a first side wall 13, a second side wall 14, a third side wall 15, and a fourth side wall 16. The first side wall 13 and the second side wall 14 are arranged along the first direction X, and the third side wall 15 and the fourth side wall 16 are arranged along the third direction Z. The first side wall 13 connects the third side wall 15 and the fourth side wall 16, and the second side wall 14 connects the third side wall 15 and the fourth side wall 16. The top wall 12 connects the first side wall 13, the second side wall 14, the third side wall 15, and the fourth side wall 16, and the bottom wall 11 connects the first side wall 13, the second side wall 14, the third side wall 15, and the fourth side wall 16 to form a receiving space. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other in pairs.

[0054] Please refer to Figure 2 and Figure 5 , in some embodiments, the battery cell 20 includes a battery cell housing 21, an electrode assembly (not shown in the figure), and an electrode terminal 22. The electrode assembly is disposed inside the battery cell housing 21, and the electrode terminal 22 connects the electrode assembly and extends out of the battery cell housing 21. That is, the battery cell 20 is a soft-pack battery cell. In other embodiments, the battery cell 20 can also be a hard-shell battery cell.

[0055] Please refer to Figure 2 and Figure 5, the battery cell 20 includes two electrode terminals 22, one of the electrode terminals 22 extends from one end of the battery cell housing 21, and the other electrode terminal 22 extends from the other end of the battery cell housing 21. Optionally, the battery cell 20 includes two electrode terminals 22, and the two electrode terminals 22 extend from the same end of the battery cell housing 21.

[0056] In some embodiments, along the second direction Y, the battery cell housing 21 includes a fifth side wall 211 facing the bottom wall 11, and the first thermal conductive adhesive 30 connects the bottom wall 11 and the fifth side wall 211.

[0057] In some embodiments, the battery pack 100 includes an insulating member 80, and the insulating member 80 connects the first thermal conductive adhesive 30 to the bottom wall 11. Along the second direction Y, the projection of each battery cell housing 21 is located within the projection of the insulating member 80, and the first thermal conductive adhesive 30 bonds the insulating member 80 and the battery cell housing 21 of the intermediate battery cell 205. Through the insulating member 80, the risk of short circuit caused by the contact between the metal layer in the battery cell housing 21 and the bottom wall 11 is reduced. Optionally, the insulating member 80 includes a polycarbonate film.

[0058] Please refer to Figure 3 and Figure 4 , in some embodiments, the heat dissipation member 60 includes heat dissipation fins 61, and the heat dissipation fins 61 are connected to the bottom wall 11. Along the second direction Y, the bottom wall 11 is located above the heat dissipation fins 61. Along the second direction Y, the heat dissipation fins 61 are separated from the first battery cell 201, the heat dissipation fins 61 are separated from the Nth battery cell 202, the heat dissipation fins 61 do not extend below the first battery cell 201 and the Nth battery cell 202, the heat dissipation fins 61 do not overlap with the first battery cell 201 in the second direction Y, and the heat dissipation fins 61 do not overlap with the Nth battery cell 202 in the second direction Y. When the heat dissipation member 60 dissipates heat from the intermediate battery cell 205, the heat dissipation effect of the heat dissipation member 60 on the first battery cell 201 and the Nth battery cell 202 can be reduced, which is beneficial to reducing the temperature difference between the first battery cell 201 and the intermediate battery cell 205 and reducing the temperature difference between the Nth battery cell 202 and the intermediate battery cell 205.

[0059] In some embodiments, along the second direction Y, the heat dissipation fins 61 are separated from the second battery cell 203, the heat dissipation fins 61 are separated from the (N - 1)th battery cell 204, along the first direction X, the heat dissipation fins 61 do not extend below the second battery cell 203 and the (N - 1)th battery cell 204, the heat dissipation fins 61 do not overlap with the second battery cell 203 in the second direction Y, and the heat dissipation fins 61 do not overlap with the (N - 1)th battery cell 204 in the second direction Y. When the heat dissipation member 60 dissipates heat from the intermediate battery cell 205, the heat dissipation effect of the heat dissipation member 60 on the second battery cell 203 and the (N - 1)th battery cell 204 can be reduced, which is beneficial to reducing the temperature difference between the second battery cell 203 and the intermediate battery cell 205 and reducing the temperature difference between the (N - 1)th battery cell 204 and the intermediate battery cell 205.

[0060] In other embodiments, the heat dissipation member 60 includes a liquid cooling plate, and the intermediate battery cell 205 is cooled by the flowing coolant within the liquid cooling plate.

[0061] The heat dissipation member 60 dissipating heat from the intermediate battery cell 205 refers to the heat dissipation member 60 actively dissipating heat from the intermediate battery cell 205. For example, when the heat dissipation member 60 is a heat dissipation fin 61, an external fan blows air towards the heat dissipation fin 61, and the heat of the intermediate battery cell 205 is taken away by air cooling. Another example is that when the heat dissipation member 60 is a liquid cooling plate, an external device drives the coolant within the liquid cooling plate to circulate, and the heat of the intermediate battery cell 205 is taken away by liquid cooling.

[0062] Please refer to Figure 3 and Figure 4 In some embodiments, the heat dissipation fin 61 is provided with a heat dissipation channel 611. The battery pack 100 includes an air inlet channel 101 located below the first battery cell 201 and an air outlet channel 102 located below the Nth battery cell 202. The air inlet channel 101 communicates with the heat dissipation channel 611, and the air outlet channel 102 communicates with the heat dissipation channel 611. The air inlet channel 101 and the heat dissipation channel 611 are beneficial for guiding the airflow blown by the fan, reducing the airflow backflow, and the airflow blown by the fan can also dissipate heat from the first battery cell 201, the second battery cell 203, the (N - 1)th battery cell 204, and the Nth battery cell 202, which is beneficial for reducing the temperature difference between the N battery cells 20. Optionally, the heat dissipation channel 611 extends along the first direction X.

[0063] Please refer to together Figures 6 to 9 In some embodiments, along the third direction Z, both sides of the bottom wall 11 are provided with bending portions 111, and the heat dissipation fins 61 are arranged between the two bending portions 111 along the third direction Z. The battery pack 100 includes a first flow guiding member 103, and along the second direction Y, the first flow guiding member 103 overlaps with the first battery cell 201. The first flow guiding member 103 connects the two bending portions 111, and the first flow guiding member 103 and the bottom wall 11 form the air inlet channel 101.

[0064] In some embodiments, along the second direction Y, a part of the heat dissipation fin 61 is located between the bottom wall 11 and the first flow guiding member 103, which is convenient for fixing the heat dissipation fin 61.

[0065] In some embodiments, the battery pack 100 includes a second flow guiding member 104, and along the second direction Y, the second flow guiding member 104 overlaps with the Nth battery cell 202. The second flow guiding member 104 connects the two bending portions 111, and the second flow guiding member 104 and the bottom wall 11 form the air outlet channel 102.

[0066] In some embodiments, along the second direction Y, a part of the heat dissipation fin 61 is located between the bottom wall 11 and the second flow guiding member 104, which is convenient for fixing the heat dissipation fin 61.

[0067] In some embodiments, the battery pack 100 includes a fixing member 105 which is located between the first current guiding member 103 and the second current guiding member 104 along the first direction X. The fixing member 105 connects two bent portions 111, further facilitating the fixing of the heat dissipation fins 61.

[0068] Please refer to Figures 2 to 4 , in some embodiments, the battery pack 100 includes a first end plate 106. Along the first direction X, the first battery cell 201 includes a first wall 2011 located on the outermost side. The first heating member 40 is connected to the first wall 2011, and a first heat insulation member 110 is provided between the first end plate 106 and the first heating member 40. When the first heating member 40 heats the first battery cell 201, through the first heat insulation member 110, the heat loss of the first battery cell 201 is slowed down, and part of the heat of the first battery cell 201 can be transferred to the second battery cell 203. When the first battery cell 201 dissipates heat, the first heat insulation member 110 can slow down the heat dissipation speed, which is beneficial to reducing the temperature difference between the outermost battery cell and the intermediate battery cell 205.

[0069] In some embodiments, the thermal conductivity of the first heat insulation member 110 is less than 0.5 W / (m·K), which is further beneficial to reducing the temperature difference between the outermost battery cell and the intermediate battery cell 205. Optionally, the first heat insulation member 110 includes foam.

[0070] In some embodiments, the battery pack 100 includes a second end plate 107. Along the first direction X, the Nth battery cell 202 includes a second wall 2021 located on the outermost side, and the second heating member 50 is connected to the second wall 2021. A second heat insulation member 120 is provided between the second end plate 107 and the second heating member 50. When the second heating member 50 heats the Nth battery cell 202, through the second heat insulation member 120, the heat loss of the Nth battery cell 202 is slowed down, and part of the heat of the Nth battery cell 202 can be transferred to the (N - 1)th battery cell 204. When the Nth battery cell 202 dissipates heat, the second heat insulation member 120 can slow down the heat dissipation speed, which is beneficial to reducing the temperature difference between the outermost battery cell and the intermediate battery cell 205.

[0071] In some embodiments, the thermal conductivity of the second heat insulation member 120 is less than 0.5 W / (m·K), which is further beneficial to reducing the temperature difference between the outermost battery cell and the intermediate battery cell 205. Optionally, the second heat insulation member 120 includes foam.

[0072] In some embodiments, the first heat insulation member 110 and the second heat insulation member 120 are in a compressed state, and the first end plate 106 and the second end plate 107 can apply a pre-pressure to the battery cells 20 through the first heat insulation member 110 and the second heat insulation member 120.

[0073] Please refer to Figure 2, in some embodiments, the battery pack 100 includes a first temperature detector 130 that detects the temperature of the first battery cell 201.

[0074] In some embodiments, the battery pack 100 includes a second temperature detector 140 that detects the temperature of the Nth battery cell 202.

[0075] In some embodiments, the battery pack 100 includes a third temperature detector 150 that detects the temperature of the middle battery cell 205. When N is odd, there is one middlemost battery cell, and the third temperature detector 150 is disposed close to the electrode terminal 22 of the middlemost battery cell. For example, when N = 5, the temperature of the middlemost battery cell is the temperature of the third battery cell. When N is even, there are two middlemost battery cells, and each middlemost battery cell has the third temperature detector 150 disposed close to the electrode terminal 22 of the battery cell. The average value of the temperatures detected by the two third temperature detectors 150 is the temperature of the middle battery cell. For example, when N = 8, the temperature of the middle battery cells is the average value of the temperatures of the fourth battery cell and the fifth battery cell.

[0076] In some embodiments, the battery pack 100 includes a first circuit board 108 that is arranged with the battery cell housing 21 along the third direction Z. The electrode terminals 21 of adjacent battery cells pass through the first circuit board 108 and are stacked, and the electrode terminal 22 is electrically connected to the first circuit board 108.

[0077] In some embodiments, the first temperature detector 130 is connected to the first circuit board 108 and is disposed close to the electrode terminal 22 of the first battery cell 201. Optionally, along the second direction Y, the distance between the first temperature detector 130 and the electrode terminal 22 of the first battery cell 201 does not exceed 3 mm, which is beneficial to accurately detecting the temperature of the first battery cell 201. It can be understood that the first temperature detector 130 can also be placed at other positions on the first circuit board 108 as long as the distance from the electrode terminal 22 of the first battery cell 201 is not more than 3 mm.

[0078] In some embodiments, the second temperature detector 140 is connected to the first circuit board 108 and is disposed close to the electrode terminal 22 of the Nth battery cell 202. Optionally, along the second direction Y, the distance between the second temperature detector 140 and the electrode terminal 22 of the Nth battery cell 202 does not exceed 3 mm, which is beneficial to accurately detecting the temperature of the Nth battery cell 202. It can be understood that the second temperature detector 140 can also be placed at other positions on the first circuit board 108 as long as the distance from the electrode terminal 22 of the Nth battery cell 202 is not more than 3 mm.

[0079] In some embodiments, the third temperature detector 150 is connected to the first circuit board 108 and is disposed close to the electrode terminal 22 of the middle battery cell 205. At this time, the middle battery cell 205 refers to the battery cell closest to the middle position among the N battery cells 20, which is conducive to accurately detecting the temperature of the battery cell at the middlemost position.

[0080] Optionally, along the second direction Y, the distance between the third temperature detector 150 and the electrode terminal 22 of the middlemost battery cell does not exceed 3 mm, which is conducive to accurately detecting the temperature of the middlemost battery cell. It can be understood that the third temperature detector 150 can also be placed at other positions of the first circuit board 108 as long as the distance from the electrode terminal 22 of the middlemost battery cell does not exceed 3 mm.

[0081] Optionally, the first circuit board 108 includes a BMS component (Battery Management System), and the BMS component includes a plurality of electronic components, and the plurality of electronic components can implement functions such as control, protection, communication, power calculation, signal transmission, and power transmission of the battery cells 20.

[0082] Optionally, the first circuit board 108 includes a flexible printed circuit (FPC, Flexible Printed Circuit). Optionally, the first circuit board 108 includes a printed circuit board (PCB, Printed Circuit Board).

[0083] When the heat dissipating member 60 dissipates heat from the middle battery cell 205 and the temperature difference between the first battery cell 201 and the middle battery cell 205 is greater than the first threshold value, the first heating member 40 heats the first battery cell 201, which is conducive to reducing the temperature difference between the first battery cell 201 and the middle battery cell 205.

[0084] In some embodiments, the first threshold value is greater than 3 °C.

[0085] When the heat dissipating member 60 dissipates heat from the middle battery cell 205 and the temperature difference between the Nth battery cell 202 and the middle battery cell 205 is greater than the second threshold value, the second heating member 50 heats the Nth battery cell 202, which is conducive to reducing the temperature difference between the Nth battery cell 202 and the middle battery cell 205.

[0086] In some embodiments, the second threshold value is greater than 3 °C.

[0087] In some embodiments, the battery pack 100 includes a second circuit board 109, and the first heating member 40 and the second heating member 50 are electrically connected to the second circuit board 109 through a wire 160. The second circuit board 109 supplies electric energy to the first heating member 40 and the second heating member 50.

[0088] Optionally, the second circuit board 109 includes a BMS component (Battery Management System), and the BMS component includes a plurality of electronic components, and the plurality of electronic components can implement functions such as control, protection, communication, power calculation, signal transmission, and power transmission of the battery cells 20.

[0089] Optionally, the second circuit board 109 includes a flexible printed circuit (FPC, Flexible Printed Circuit). Optionally, the second circuit board 109 includes a printed circuit board (PCB, Printed Circuit Board).

[0090] Please refer to Figures 10 to 12 , this application provides an energy storage device 200, which includes a cabinet 210, a fan 220, and a plurality of battery packs 100 in any one of the above embodiments. The plurality of battery packs 100 are arranged in the cabinet 210.

[0091] In some embodiments, the cabinet 210 includes a first door 210A and a second door 210B. The first door 210A is provided with an air inlet 2101, and the second door 210B is provided with an air outlet 2102. The plurality of battery packs 100 are located between the first door 210A and the second door 210B. The fan 220 is configured to blow air towards the heat dissipation member 60, and the air flow blows through the heat dissipation member 60, takes away the heat, and is discharged to the outside of the energy storage device 200 through the air outlet 2102.

[0092] In some embodiments, the energy storage device 200 of this application may be, but is not limited to, a backup power supply, a large battery module, etc.

[0093] Those of ordinary skill in the art of this technology should recognize that the above embodiments are only used to illustrate this application, rather than to limit this application. As long as appropriate changes and variations are made to the above embodiments within the scope of the spirit of this application, they fall within the scope of the disclosure of this application.

Claims

1. A battery pack, characterized in that: include a housing including a bottom wall; N battery cells arranged along a first direction are located in the housing and disposed on the bottom wall, N is an integer greater than or equal to 5, and along the first direction, the N battery cells include a first battery cell and an Nth battery cell located at the outermost sides, a second battery cell and an N-1th battery cell, and an intermediate battery cell located between the second battery cell and the N-1th battery cell; A first thermally conductive adhesive, connecting the middle battery core and the bottom wall; a first heating element, connected to the first battery core, and configured to heat the first battery core; a second heating element connected to the Nth battery cell, wherein the second heating element is configured to heat the Nth battery cell; A heat sink is located on a side of the bottom wall away from the battery core, and is configured to dissipate heat for the middle battery core.

2. The battery pack according to claim 1, wherein: The heat sink comprises heat dissipation fins, and the heat dissipation fins are connected to the bottom wall; Along the second direction, the bottom wall is located above the heat dissipation fins, the heat dissipation fins are separated from the first battery cell, the heat dissipation fins are separated from the Nth battery cell, and the second direction is perpendicular to the first direction.

3. The battery pack according to claim 2, characterized in that: The heat dissipation fins are provided with heat dissipation channels; The battery pack includes an air inlet channel located below the first battery cell and an air outlet channel located below the Nth battery cell, the air inlet channel is connected to the heat dissipation channel, and the air outlet channel is connected to the heat dissipation channel.

4. The battery pack according to any one of claims 1 to 3, characterized in that: The battery pack includes an insulating member, and the insulating member connects the first thermal conductive adhesive to the bottom wall; Each of the battery cells includes a battery cell shell, and along the second direction, a projection of each of the battery cell shells is located within a projection of the insulating member. The first thermally conductive adhesive bonds the insulating component and the cell shell of the middle cell.

5. The battery pack according to any one of claims 1 to 4, characterized in that: The thermal conductivity of the first thermally conductive adhesive is 0.8W / (m·K)‌-2W / (m·K)‌.

6. The battery pack according to any one of claims 1 to 5, characterized in that: The battery pack includes a first end plate, and along the first direction, the first battery cell includes a first wall located at the outermost side; The first heating element is connected to the first wall. A first heat-insulating element is provided between the first end plate and the first heating element. The thermal conductivity of the first heat-insulating element is less than 0.5 W / (m·K).

7. The battery pack according to any one of claims 1 to 6, characterized in that: The battery pack includes a second end plate. Along the first direction, the Nth battery cell includes a second wall located on the outermost side. The second heating element is connected to the second wall. A second thermal insulation element is provided between the second end plate and the second heating element. The thermal conductivity of the second thermal insulation element is less than 0.5 W / (m·K).

8. The battery pack according to any one of claims 1 to 7, characterized in that: The battery pack comprises a first temperature detection member, a second temperature detection member and a third temperature detection member, wherein the first temperature detection member detects the temperature of the first battery cell, the second temperature detection member detects the temperature of the Nth battery cell, and the third temperature detection member detects the temperature of the middle battery cell; When the heat dissipation element dissipates heat for the middle battery cell and the temperature difference between the first battery cell and the middle battery cell is greater than a first threshold, the first heating element heats the first battery cell; When the heat dissipating element dissipates heat from the middle battery cell, and the temperature difference between the Nth battery cell and the middle battery cell is greater than a second threshold, the second heating element heats the Nth battery cell.

9. The battery pack according to claim 8, characterized in that: The first threshold is greater than 3°C, and the second threshold is greater than 3°C.

10. An energy storage device, characterized in that: include: The cabinet comprises a first door body and a second door body, wherein the first door body is provided with an air inlet, and the second door body is provided with an air outlet; A plurality of battery packs arranged along the second direction as claimed in any one of claims 1 to 9, wherein the plurality of battery packs are arranged in the cabinet; The fan is configured to blow air toward the heat sink.

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