Energy storage device

Abstract

The invention provides energy storage equipment. The energy storage equipment comprises a shell, a heat exchanger and a plurality of battery modules, the plurality of battery modules are arranged in the shell. The shell comprises a first wall and a second wall, the multiple battery modules and the first wall are arranged in the first direction, and the heat exchanger is fixed to the second wall. The heat exchanger is configured in such a manner that gas inside the housing exchanges heat with gas outside the housing through the heat exchange member. The heat exchanger comprises a first air inlet, a first air outlet and a first channel. The first air inlet and the first air outlet are located in the side, away from the battery modules, of the heat exchanger, and the first air outlet is closer to the first wall than the first air inlet in the first direction. The first air inlet communicates with the first exhaust port through the first channel, and the first exhaust port and the first air inlet communicate with the outside of the shell. According to the energy storage equipment, heat generated by the multiple battery modules is transferred to the outside of the shell through the heat exchanger, the temperature in the shell is reduced, the performance of the battery cells in the battery modules is improved, and the service life of the battery cells in the battery modules is prolonged.

Description

Technical Field

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

[0002] The battery cells or other electrical components inside the energy storage device generate heat during operation. If the heat is not dissipated in time, the internal temperature of the energy storage device will be too high, thereby affecting the performance and service life of the battery cells. Summary of the invention

[0003] The purpose of this application is to provide an energy storage device, aiming to improve the temperature inside the energy storage device, thereby improving the performance and service life of the battery cell.

[0004] The present application provides an energy storage device, which includes a shell, a heat exchanger and a plurality of battery modules. The plurality of battery modules are arranged in the shell. The shell includes a first wall and a second wall, the plurality of battery modules are arranged along a first direction with the first wall, and the heat exchanger is fixed to the second wall. The heat exchanger includes a heat exchange element, and the heat exchange element is configured so that the gas inside the shell exchanges heat with the gas outside the shell through the heat exchange element. The heat exchanger includes a first air inlet, a first exhaust port and a first channel. The first air inlet and the first exhaust port are located on a side of the heat exchanger away from the plurality of battery modules, and along the first direction, the first exhaust port is closer to the first wall than the first air inlet. The first channel connects the first air inlet with the first exhaust port, and the first exhaust port and the first air inlet are both connected to the outside of the shell. The energy storage device of the present application transfers the heat generated by the plurality of battery modules to the outside of the shell through the heat exchanger, reduces the temperature inside the shell, and improves the performance and service life of the battery cells in the battery module.

[0005] As an optional implementation, the first channel is configured to guide the first gas to be discharged from the first exhaust port and away from the first air inlet. The angle between the discharge direction of the first gas and the first direction is an acute angle. The first gas is defined as the gas that enters the heat exchanger from the outside of the shell. With this arrangement, on the one hand, the discharge of the first gas is less hindered by the inner wall of the outer shell, and the discharge path of the first gas is relatively smooth; on the other hand, the discharge direction of the first gas is inclined outward, and the first gas is further away from the energy storage device after being discharged, so that the total amount of higher temperature gas falling back to the first air inlet is reduced, and the external circulation cooling effect of the energy storage device is further improved.

[0006] As an optional implementation, the heat exchanger includes a box and a first fan. The box is fixed to the second wall, the heat exchange element is arranged in the box, and the first fan is arranged on a side of the heat exchanger away from the multiple battery modules. Wherein, along the first direction, the first fan is closer to the first air inlet than the first exhaust port. Arranging the first fan at the air inlet improves the premature formation of condensed water droplets in the box, reduces the risk of frost in a cooling environment, and prolongs the service life of the energy storage device.

[0007] As an optional implementation, the heat exchanger includes a second fan, a second air inlet, a second exhaust port and a second channel. The second channel is separated from the first channel, and the second channel connects the second air inlet with the second exhaust port. The second air inlet and the second exhaust port are both connected to the interior of the shell. The second fan, the second air inlet and the second exhaust port are arranged on a side of the heat exchanger close to the multiple battery modules. Along the first direction, the second exhaust port is farther away from the first wall than the second air inlet, and the second fan is closer to the second air inlet than the second exhaust port. The second fan is arranged at the exhaust, and when the second fan is in working state, the first gas is accelerated to enter the heat exchanger, thereby improving the heat exchange efficiency.

[0008] As an optional implementation, the second channel is configured to guide the second gas to be discharged from the second exhaust port and away from the second air inlet. The angle between the discharge direction of the second gas and the first direction is an obtuse angle. The second gas is defined as the gas located inside the shell. In this way, the discharge of the second gas is less obstructed by the inner shell, and the discharge path of the second gas is relatively smooth.

[0009] As an optional implementation, the housing includes a third wall, and along a second direction perpendicular to the first direction, the second wall, a plurality of battery modules and the third wall are arranged at intervals. The energy storage device includes a first gap, a second gap, a third gap and a fourth gap. Among them, the first gap is located between the first wall and the plurality of battery modules. The second gap is located between the second wall and the plurality of battery modules. The third gap is located between the third wall and the plurality of battery modules. Along the first direction, the plurality of battery modules are arranged at intervals. The fourth gap is located between adjacent and spaced battery modules. The first fan is configured to drive the first gas into the heat exchanger from the first air inlet and discharged from the first exhaust port. The second fan is configured to drive the second gas into the heat exchanger from the second air inlet and discharged from the second exhaust port to flow in the second gap, the fourth gap, the third gap and the first gap.

[0010] As an optional implementation, the battery module includes a plurality of battery cells. The plurality of battery cells are arranged along a second direction perpendicular to the first direction. Along the second direction, the battery module includes a first end and a second end. The thermal resistance between the battery cell and the first end is greater than the thermal resistance between the battery cell and the second end. The first end is defined as an end of the battery module close to the heat exchanger, and the second end is defined as an end of the battery module away from the heat exchanger. In the present application, the heat exchanger is arranged on the second wall. Along the second direction, the temperature of a part of the area close to the heat exchanger in the outer shell is relatively low, while the temperature of a part of the area away from the heat exchanger in the outer shell is relatively high. This is reflected in a single battery module, where the temperature of the first end is relatively low and the temperature of the second end is relatively high. While reducing the heat dissipation capacity of the first end, the heat dissipation capacity of the second end is increased, the temperature difference of each battery cell arranged along the second direction is balanced, the temperature consistency between the battery cells is improved, and the service life of the battery module is extended.

[0011] As an optional implementation, the battery module includes a top wall and a bottom wall. A plurality of battery cells are located between the top wall and the bottom wall. The top wall and the bottom wall each include a first portion close to one end of the heat exchanger and a second portion away from one end of the heat exchanger. Along a first direction, a distance between the first portion and the battery cell is greater than a distance between the second portion and the battery cell.

[0012] As an optional implementation, the second portion includes a recessed portion. Along the first direction, a distance between the first portion and the battery cell is greater than a distance between the recessed portion and the battery cell.

[0013] As an optional implementation, the battery module includes an elastic member, which is arranged between the first part and the battery cell. When the battery cell expands, the elastic member absorbs the expansion force of the battery cell and reduces the expansion force on the first part.

[0014] As an optional implementation, the elastic member includes foam. The thermal conductivity of the foam is less than 0.5 W / m·K, which reduces heat exchange between the battery core and the first part.

[0015] As an optional implementation, the battery module includes a thermally conductive adhesive, which is disposed between the second portion and the battery cell. The thermal conductivity of the thermally conductive adhesive 25 is greater than 0.5 W / m·K, which facilitates heat exchange between the battery cell 21 and the second portion 2202 .

[0016] As an optional implementation, the number of battery modules is N1, and the N1 battery modules are divided into M1 battery module sets, and two adjacent battery module sets share one battery module. Among them, M1 and N1 satisfy: 2≤M1<N1, and N1 is a positive integer greater than or equal to 3. Each battery module set includes at least two battery modules. Along the first direction, adjacent battery modules of each battery module set are arranged at intervals to form a fourth gap. The M2th battery module set to the M3th battery module set are arranged along the first direction. The fourth gap between adjacent battery modules in the M3th battery module set is greater than the fourth gap between adjacent battery modules in the M2th battery module set. Among them, M1, M2 and M3 satisfy: 1≤M2<M3≤M1, and M1, M2 and M3 are all positive integers. The present application optimizes the arrangement of the battery modules, and the fourth gap located in the M2 group of battery modules becomes smaller, thereby increasing the resistance of the first gas passing through the fourth gap located in the M2 group of battery modules, and the fourth gap 1b located in the M3 group of battery modules becomes larger, thereby reducing the resistance of the first gas passing through the fourth gap located in the M3 group of battery modules, so as to balance the temperature difference between the upper and lower areas in the outer casing, and make the heat dissipation speeds of the battery modules located in the upper and lower areas tend to be consistent, which is beneficial to maintaining the temperature balance of each battery module 20 and improving the reliability of the energy storage device.

[0017] As an optional implementation manner, along the first direction, the fourth gaps between adjacent battery modules in the N1 battery modules gradually increase.

[0018] As an optional implementation, when 2<M1<N1, the fourth gaps between adjacent battery modules in each battery module set are equal.

[0019] As an optional implementation, when M1=2, the two battery module sets include a first battery module set and a second battery module set. Along the first direction, the first battery module set and the second battery module set are arranged. The first battery module set includes N2 battery modules. The second battery module set includes N3 battery modules. In the first battery module, the first battery module is the bottom battery module to the N2 battery module, and the fourth gap between adjacent battery modules is L1 mm.

[0020] In the N2-th battery module to the N3-th battery module, the fourth gap between adjacent battery modules is L2 mm. Among them, N1, N2, and N3 satisfy: N2+N3=N1, N2 and N3 are both positive integers; and L1 and L2 satisfy: L1<L2.

[0021] As an optional implementation, 5≤L1≤20.

[0022] As an optional implementation, L1≤5×K1≤L2≤20×K2; wherein, 1.2≤K1≤1.5, 1.2≤K2≤1.5.

[0023] As an optional implementation, the energy storage device includes a windshield. The windshield is arranged in the third gap and is inclined relative to the third wall. Along the first direction, the windshield includes a third end and a fourth end. The third end is farther away from the third wall than the fourth end. In this way, the windshield is arranged obliquely, so that along the first direction, the flow rate of the first gas in the third gap decreases as the distance between the multiple battery modules and the windshield gradually increases, further making the heat dissipation speed of each battery module located in the upper and lower areas tend to be consistent.

[0024] As an optional implementation, the energy storage device includes a pipeline. The pipeline extends from the first gap toward the heat exchanger and is connected to the heat exchanger. The pipeline connects the second air inlet to the first gap. In the present application, the setting of the pipeline allows the first gas to flow unidirectionally in the shell, reducing the flow resistance of backflow and / or mixed flow, and improving the heat exchange efficiency of the heat exchanger.

[0025] As an optional implementation, the energy storage device includes a pressure relief portion, which is disposed on the first wall and is configured to discharge the second gas through the pressure relief space. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of an energy storage device in a closed state provided in an embodiment of the present application;

[0027] Figure 2 for Figure 1 An exploded view of the structure of the energy storage device shown;

[0028] Figure 3 A schematic diagram of the structure of an energy storage device in an open state provided in an embodiment of the present application;

[0029] Figure 4 It is a partial structural schematic diagram of an embodiment of the present application;

[0030] Figure 5 for Figure 1 A partial cutaway view of the energy storage device shown at another angle;

[0031] Figure 6a for Figure 1 The local enlarged view obtained after cutting along the AA line;

[0032] Figure 6b for Figure 1 One of the cross-sectional views along line AA shows the path of heat exchange between the internal and external gases of the energy storage device;

[0033] Figure 6c for Figure 1 Another section view along line AA;

[0034] Figure 6d for Figure 1 Another section view along line AA;

[0035] Figure 7a for Figure 6c A schematic diagram of one arrangement of the battery modules along a first direction;

[0036] Figure 7b for Figure 6c A schematic diagram of another arrangement of the battery modules along the first direction;

[0037] Figure 7c for Figure 6c A schematic diagram of another arrangement of the battery modules along the first direction;

[0038] Figure 8 for Figure 2 A schematic structural diagram of a heat exchanger of an energy storage device is shown;

[0039] Fig. 9 for Figure 8 A cross-sectional view of the heat exchanger along line BB is shown;

[0040] Fig.10 for Figure 2 A schematic diagram of the structure of a battery module of an energy storage device shown;

[0041] Fig.11 for Fig.10 A cross-sectional view of the battery module along line CC is shown;

[0042] Reference numerals:

[0043] 10. housing; 10a. housing opening; 11. first wall; 111. second opening; 12. second wall; 121. first opening; 13. third wall; 14. fourth wall; 15. fifth wall; 16. sixth wall;

[0044] 20, battery module; 2, battery module set; 2', first battery module set; 2", second battery module set; 201, first end; 202, second end; 21, battery cell; 221, top wall; 222, bottom wall; 2201, first part; 22021, recess; 24, elastic member; 25, thermal conductive adhesive;

[0045] 30, heat exchanger; 30a, first channel; 30b, second channel; 31, heat exchange element; 32, housing; 32a, first cavity; 32b, second cavity; 321, inner housing; 322, outer housing; 323, connecting flange; 30c, first air inlet; 30d, first air outlet; 33, first fan; 30e, second air inlet; 30f, second air outlet; 34, second fan;

[0046] 40. Pressure relief unit;

[0047] 50, receiving space; 50aa, first chamber; 50ab, second chamber;

[0048] 60. Liang;

[0049] 70. Partition;

[0050] 1a, first gap; 1b, fourth gap; 1c, second gap; 1d, third gap;

[0051] 80. Windshield;

[0052] 90. Pipeline;

[0053] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0054] In this document, the terms "first", "second", etc. are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or order. For example, the first application, the second application, etc. are used to distinguish different applications, rather than to describe a specific order of applications. Features defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0055] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, unless otherwise specified, "plurality" means two or more.

[0056] In addition, in this article, directional terms such as "upper" and "lower" are defined relative to the orientation of the structure schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to the change of the orientation of the structure.

[0057] The technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0058] Figure 1 This is a schematic diagram of the structure of an energy storage device in a closed state provided in an embodiment of the present application. Figure 2 for Figure 1 An exploded diagram of the structure of the energy storage device is shown.

[0059] Please also see Figure 1 and Figure 2The energy storage device includes a housing 10 and a plurality of battery modules 20 , and the plurality of battery modules 20 are disposed in the housing 10 .

[0060] The energy storage device includes a heat exchanger 30 , which is fixedly connected to the housing 10 .

[0061] In some embodiments, the heat exchanger 30 is in communication with the inside of the housing 10 and the outside of the housing 10. The second gas G2 exchanges heat with the first gas G1 through the heat exchanger 30 to dissipate heat from the plurality of battery modules 20.

[0062] In some embodiments, the first gas G1 is the gas entering the heat exchanger 30 from the outside of the housing 10, and the second gas G2 is the gas located inside the housing 10. It is understandable that when the temperature of the first gas G1 is lower than the temperature of the second gas G2, the heat exchanger 30 is used to perform heat exchange between the first gas G1 and the second gas G2 to reduce the temperature of the second gas G2, and then the second gas G2 is used to dissipate heat from the battery module 20.

[0063] The energy storage device of the present application transfers the heat generated by the multiple battery modules 20 to the outside of the housing 10 through the heat exchanger 30, thereby reducing the temperature inside the housing 10, maintaining the operating stability of the multiple battery modules 20, and improving the operating efficiency of the energy storage device.

[0064] Continue as Figure 1 and Figure 2 As shown, in some embodiments, the energy storage device includes a pressure relief portion 40, which is disposed on the housing 10, and the second gas G2 is released to the outside of the housing 10 through the pressure relief portion 40. In some embodiments, the second gas G2 includes gas released when the battery module 20 is depressurized.

[0065] Figure 3 This is a schematic diagram of the structure of the energy storage device in an open state provided in an embodiment of the present application. Please refer to Figure 1 and Figure 3 In some embodiments, the energy storage device includes a receiving space 50a. The heat exchanger 30, the pressure relief portion 40 and the housing 10 together define the receiving space 50a, and the plurality of battery modules 20 are located in the receiving space 50a.

[0066] Figure 4 This is a partial structural diagram of an embodiment of the present application. Please refer to Figure 2-Figure 4 In some embodiments, the housing 10 includes a housing opening 10a, and the housing opening 10a is communicated with the receiving space 50a.

[0067] In some specific implementations, the housing 10 includes a first wall 11, a second wall 12, a third wall 13, a fourth wall 14, a fifth wall 15, and a sixth wall 16. Along the first direction X, the sixth wall 16 is disposed opposite to the first wall 11, along the second direction Y, the second wall 12 is disposed opposite to the third wall 13, and along the third direction Z, the fourth wall 14 is disposed opposite to the fifth wall 15.

[0068] The second wall 12 and the third wall 13 are respectively connected to the first wall 11 , the fourth wall 14 , the fifth wall 15 and the sixth wall 16 to form a frame structure, namely, the housing 10 of the energy storage device.

[0069] The frame structure includes a housing opening 10a, such as Figure 2 As shown, when the second wall 12 is in the open state, the housing opening 10 a is observed along the second direction Y. It can be understood that when the second wall 12 is in the closed state, the second wall 12 covers the housing opening 10 a.

[0070] Generally, when the energy storage device is in operation, the second wall 12 is closed relative to the frame structure, and the receiving space 50a is isolated from the external environment of the energy storage device to form a closed space. The closed space is isolated from the external environment, which reduces the entry of debris such as dust, conductive materials, water vapor, salt spray, etc. into the battery module 20, reduces the corrosion of water vapor and salt spray to the battery module 20 and other electrical components, reduces the risk of short circuit of electrical components, and improves the safety performance of the energy storage device.

[0071] When the energy storage device is being repaired, the second wall 12 is in an open state, and the receiving space 50a is in communication with the external environment.

[0072] In some embodiments, the first direction X is the height direction of the energy storage device, the second direction Y is the depth direction of the energy storage device, and the third direction Z is the width direction of the energy storage device, wherein any two of the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0073] Continue as Figure 3 As shown, in some embodiments, the heat exchanger 30 closes a portion of the housing opening 10a.

[0074] Continue as Figure 2 As shown, in some embodiments, the second wall 12 includes a first opening 121, and the heat exchanger 30 closes the first opening 121. It can be understood that, in this embodiment, the heat exchanger 30 and the second wall 12 together close the housing opening 10a.

[0075] In some optional embodiments, the energy storage device includes a plurality of beams 60 , and the plurality of beams 60 extend along the second direction Y. The plurality of beams 60 are located in the housing 10 and are used to carry the battery module 20 .

[0076] Continue as Figure 2As shown, in some embodiments, the first wall 11 includes a second opening 111 , the pressure relief portion 40 closes the second opening 111 , and along the first direction X, the sixth wall 16 is disposed opposite to the pressure relief portion 40 and the first wall 11 , respectively.

[0077] Please continue to see Figure 2 In some embodiments, the energy storage device includes a partition 70, which is disposed in the frame structure. The partition 70 divides the receiving space 50a into a first chamber 50aa and a second chamber 50ab arranged along the third direction Z.

[0078] The energy storage device includes an electrical component, the electrical component is located in one of the first compartment 50aa and the second compartment 50ab, the multiple battery modules 20 are located in the other of the first compartment 50aa and the second compartment 50ab, and the electrical component is electrically connected to the multiple battery modules 20. The electrical component and the battery module 20 are arranged in different compartments, respectively, and the heat emitted by the electrical component is isolated from the heat emitted by the multiple battery modules 20, thereby reducing the superposition effect of the heat generated by the electrical component and the heat generated by the multiple battery modules 20.

[0079] In some specific implementations, the first compartment 50aa includes a housing opening 10a, a plurality of battery modules 20 are located in the first compartment 50aa, and the electrical components are located in the second compartment 50ab.

[0080] In some specific implementations, the combined structure of the second wall 12 and the heat exchanger 30 , the plurality of battery modules 20 and the third wall 13 are arranged along the second direction Y, and the fourth wall 14 , the partition 70 and the fifth wall 15 are arranged along the third direction Z.

[0081] In some embodiments, the electrical component includes a battery management system (BMS), which is electrically connected to the plurality of battery modules 20 and is used to control the charging and discharging of each battery module 20. It is understandable that the BMS is presented in the form of a printed circuit board, which includes electronic components such as a microcontroller unit, resistors, capacitors, and electrical switches.

[0082] In some embodiments, the electrical component includes a power conversion system (PCS), which is electrically connected to a plurality of battery modules 20 to perform AC and DC conversion.

[0083] In some embodiments, the electrical component includes a controller, and the controller controls the heat exchanger 30 to dissipate heat for the multiple battery modules 20. Exemplarily, the controller that controls the heat exchanger 30 and the controller that controls the charging and discharging of the battery module 20 are the same electronic device, such as a microcontroller unit provided on a battery management system. It is understandable that the controller that controls the heat exchanger 30 and the controller that controls the charging and discharging of the battery module 20 are different electronic devices.

[0084] See also Figure 4 , Figure 6c and Figure 6d In some embodiments, along the first direction X, a plurality of battery modules 20 are arranged at intervals from the first wall 11 .

[0085] In some specific implementations, along the first direction X, there is a first gap 1a between the plurality of battery modules 20 and the first wall 11, and there is a fourth gap 1b between adjacent battery modules 20. Under the internal circulation of the heat exchanger 30, the second gas G2 takes away the heat emitted by the battery module 20 when passing through the fourth gap 1b. Afterwards, the second gas G2 carrying the heat flows into the heat exchanger 30 through the first gap 1a, and exchanges heat with the first gas G1 to reduce the temperature of the second gas G2. The cooled second gas G2 is blown toward the battery module 20 to reduce the temperature of the battery module 20. It is understandable that the fourth gap 1b mentioned here specifically refers to the gap between two adjacent battery modules 20, and may also refer to the gap between multiple battery modules 20 and battery modules 20 adjacent to multiple battery modules 20.

[0086] Please continue to see Figure 6a-6d In some embodiments, along the second direction Y, the second wall 12 , the plurality of battery modules 20 , and the third wall 13 are arranged at intervals.

[0087] In some specific implementations, along the second direction Y, there is a second gap 1c between the second wall 12 and the plurality of battery modules 20, and a third gap 1d between the plurality of battery modules 20 and the third wall 13. Along the second direction Y, the second gap 1c, the first gap 1a, the plurality of fourth gaps 1b, and the third gap 1d are connected. Under the internal circulation of the heat exchanger 30, the second gas G2 circulates in the plurality of fourth gaps 1b, the third gap 1d, the first gap 1a, the heat exchanger 30, and the second gap 1c, wherein the second gas G2 carrying heat enters the heat exchanger 30 to exchange heat with the first gas G1, thereby reducing the temperature of the second gas G2, and the cooled second gas G2 is blown toward the battery module 20 to reduce the temperature of the battery module 20. The second gas G2 is depressurized to the outside of the housing 10 through the first gap 1c and the pressure relief portion 40.

[0088] In some specific implementations, the gas released when the battery module 20 is depressurized is released to the outside of the housing 10 through the second gap 1 c and the pressure relief portion 40 .

[0089] In some optional embodiments, the heat exchanger 30 serves as the second wall 12 of the energy storage device, and along the second direction Y, the heat exchanger 30 , the plurality of battery modules 20 , and the third wall 13 are arranged at intervals.

[0090] See also Figure 7a In some embodiments, the number of battery modules 20 is N1, and the N1 battery modules 20 are divided into M1 battery module sets 2, and two adjacent battery module sets 2 share the same battery module 20. Each battery module set 2 includes at least two battery modules 20, and along the first direction X, the adjacent battery modules 20 of each battery module set 2 are arranged at intervals to form a fourth gap 1b;

[0091] The M2 th battery module set 2 to the M3 th battery module set 2 are arranged along the first direction X. The M2 th battery module set 2 is closer to the sixth wall 16 than the M3 th battery module set 2 , and the M3 th battery module set 2 is closer to the first wall 11 than the M2 th battery module set 2 .

[0092] The fourth gaps 1 b between adjacent battery modules 20 in the M3-th battery module set 2 are greater than the fourth gaps 1 b between adjacent battery modules 20 in the M2-th battery module set 2 .

[0093] Among them, M1 and N1 satisfy: 2≤M1<N1; M1, M2 and M3 satisfy: 1≤M2<M3≤M1, M1, M2, M3 are all positive integers, and N1 is a positive integer greater than or equal to 3.

[0094] The present application optimizes the arrangement of the battery modules 20, and the fourth gap 1b located in the M2 battery module set 2 becomes smaller, thereby increasing the resistance of the first gas G1 passing through the fourth gap 1b in the M2 battery module set 2, and the fourth gap 1b located in the M3 battery module set 2 becomes larger, thereby reducing the resistance of the first gas G1 passing through the fourth gap 1b in the M3 battery module set 2, so as to balance the temperature difference between the upper and lower areas in the outer casing 10, and make the heat dissipation speeds of the battery modules 20 located in the upper and lower areas tend to be consistent, which is beneficial to maintaining the temperature balance of each battery module 20 and improving the reliability of the energy storage device.

[0095] like Figure 7cAs shown, in some embodiments, when M1 is 2, the two battery module sets 2 include a first battery module set 2' and a second battery module set 2". Along a first direction X, the first battery module set 2' and the second battery module set 2" are arranged, the first battery module set 2' is closer to the sixth wall 16 than the second battery module set 2", and the second battery module set 2" is closer to the first wall 11 than the first battery module set 2'. The first battery module set 2' includes N2 battery modules 20, and the second battery module set 2 includes N3 battery modules 20.

[0096] In the first battery module 20 to the N2th battery module 20, the fourth gap 1b between adjacent battery modules 20 is L1 mm. In the N2th battery module 20 to the N3th battery module 20, the fourth gap 1b between adjacent battery modules 20 is L2 mm, and L1 and L2 satisfy: L1<L2.

[0097] In some specific implementations, 5≤L1≤20. Exemplarily, L1 is 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20 or a numerical range between any two thereof. Within this value range, L1 increases the resistance of the first gas G1 passing through the fourth gap 1b between adjacent battery modules 20 in the first battery module set 2'.

[0098] In some specific implementations, L1≤5×K1≤L2≤20×K2. Among them, 1.2≤K1≤1.5, 1.2≤K2≤1.5. It can be understood that K1 and K2 take the same value or different values ​​according to the actual situation, and no specific limitation is made here. For example, when K1 and K2 are both 1.2, L2 is 6, 8, 10, 12, 14, 16, 18, 20, 22, 24 or a numerical range between any two of them. For another example, when K1 takes 1.2 and K2 takes 1.5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30 or a numerical range between any two of them.

[0099] Alternatively, if Figure 7b As shown, in some other embodiments, when 2<M1<N1, the fourth gaps 1b between adjacent battery modules 20 in each battery module set 2 are all equal.

[0100] Alternatively, if Figure 7a As shown, in some other embodiments, along the first direction X, the fourth gap 1 b between adjacent battery modules 20 in the N1 battery modules 20 gradually increases.

[0101] Figure 6d for Figure 1Another cross-sectional view along the AA line is shown in FIG6. In some embodiments, the energy storage device includes a windshield 80, which is arranged in the third gap 1d and is inclined relative to the third wall 13. Along the first direction X, the windshield 80 includes a third end 801 and a fourth end 802, and the third end 801 is farther away from the third wall 13 than the fourth end 802. In this way, on the basis of the fourth gap 1b in the M2 battery module set 2 becoming smaller, the windshield 80 is arranged as follows: Figure 6d The inclined arrangement shown makes the flow rate of the first gas G1 in the third gap 1d along the first direction X decrease as the distance between the multiple battery modules 20 and the wind shield 80 gradually increases, further making the heat dissipation speed of each battery module 20 located in the upper and lower areas tend to be consistent.

[0102] Please combine Fig. 9 Return together Figure 6a-6d In some embodiments, the heat exchanger 30 includes a first channel 30a and a second channel 30b, and the first channel 30a and the second channel 30b are separated. It is understandable that the separation of the first channel 30a and the second channel 30b mentioned here means that the first channel 30a and the second channel 30b are not connected to each other, blocking the mutual flow between the first gas G1 and the second gas G2, so that the first gas G1 in the first channel 30a and the second gas G2 in the second channel 30b are not directly exchanged, which is conducive to reducing the temperature of the second gas G2 and improving the cooling effect of the second gas G2.

[0103] In some specific implementations, the heat exchanger 30 includes a heat exchange element 31, at least a portion of the first channel 30a and at least a portion of the second channel 30b are located in the heat exchange element 31, the first channel 30a is communicated with the outside of the housing 10, and the second channel 30b is communicated with the inside of the housing 10. The second gas G2 enters the second channel 30b, and the first gas G1 enters the first channel 30a, and heat exchange is performed through the heat exchange element 31 to transfer the heat generated by the multiple battery modules 20 to the outside of the housing 10.

[0104] In some specific implementations, the heat exchange element 31 includes a multi-fin structure, which has a stirring effect on the first gas G1 and / or the second gas G2, thereby increasing the heat transfer coefficient of the heat exchange element 31.

[0105] In some specific implementations, the end of the first channel 30a of the heat exchange element 31 adjacent to the first exhaust port 30d is closed to reduce the first gas G1 from escaping from the first channel 30a to the outside of the housing. The end of the second channel 30b of the heat exchange element 31 adjacent to the second exhaust port 30f is closed to reduce the second gas G2 from escaping from the second channel 30b to the outside of the housing 10.

[0106] Please combine Figure 6a-6d See also Figure 1 or Figure 2 In some embodiments, the heat exchanger 30 includes a box body 32, the box body 32 is fixedly connected to the second wall 12, and the heat exchange element 31 is disposed in the box body 32. Among them, as such a fixed connection method, welding, clamping, threaded connection, etc. can be listed.

[0107] In some embodiments, the housing 32 includes an inner housing 321, an outer housing 322, and a connecting flange 323. The inner housing 321 and the outer housing 322 are connected and enclosed to form a receiving chamber (not shown). At least a portion of the heat exchange element 31 is disposed in the receiving chamber, and the receiving chamber is divided into a first chamber 32a and a second chamber 32b along the first direction X. The connecting flange 323 is connected to one of the inner housing 321 or the outer housing 322. Both the inner housing 321 and the outer housing 322 are fixedly connected to the second wall 12 through the connecting flange 323.

[0108] In some specific implementations, the outer shell 322 protrudes from the second wall 12 in the opposite direction of the second direction Y and is disposed away from the battery module 20 . In the second direction Y, the inner shell 321 protrudes from the second wall 12 and is disposed toward the battery module 20 .

[0109] In some embodiments, the first air inlet 30c, the first air outlet 30d and the first fan 33 are located on a side of the heat exchanger 30 away from the plurality of battery modules 20, for example, the first air inlet 30c, the first air outlet 30d and the first fan 33 are disposed on the outer shell 322. The second fan 34, the second air inlet 30e and the second air outlet 30f are disposed on a side of the heat exchanger 30 close to the plurality of battery modules 20, for example, the second fan 34, the second air inlet 30e and the second air outlet 30f are disposed on the inner shell 321.

[0110] In some specific implementations, the connecting flange 323 is connected to the outer shell 322 .

[0111] In some specific implementations, the first cavity 32a is substantially as follows: Figure 6b The regular rectangular space shown, and / or, the second cavity 32b is substantially as follows Figure 6b Alternatively, the first cavity 32a is substantially an L-shaped or Z-shaped space, and / or the second cavity 32b is substantially an L-shaped or Z-shaped space.

[0112] Please combine Figure 6b See also Figure 1 or Figure 2 In some embodiments, the heat exchanger 30 includes a first air inlet 30c and a first exhaust port 30d, the first channel 30a connects the first air inlet 30c with the first exhaust port 30d, and the first exhaust port 30d and the first air inlet 30c are both connected to the outside of the housing 10.

[0113] In some specific implementations, the first air inlet 30c, the first air outlet 30d, and the first channel 30a are located on a side of the heat exchange element 31 away from the plurality of battery modules 20. Along the first direction X, the first air outlet 30d is closer to the first wall 11 than the first air inlet 30c. Under the external circulation of the heat exchanger 30, after the first air inlet 30c inhales the first gas G1 with a lower temperature, the first gas G1 is converted into a gas with a higher temperature through the heat exchange of the heat exchange element 31 and discharged from the first exhaust port 30d. At this time, the density of the gas with a higher temperature is smaller, which reduces the amount of the gas with a higher temperature falling back to the first air inlet 30c, and the external circulation cooling effect of the energy storage device is improved.

[0114] In some specific implementations, the first air inlet 30c and the first air outlet 30d are both disposed in the outer shell 322. Along the first direction X, the first air inlet 30c is adjacent to the end wall of the heat exchange element 31 close to the first channel 30a. Along the second direction Y, the projection of the first air outlet 30d at least partially overlaps with the projection of the heat exchange element 31.

[0115] In some specific implementations, the first air inlet 30c is communicated with one end of the first channel 30a through the first cavity 32a, and the second air inlet 30e is communicated with one end of the second channel 30b through the second cavity 32b.

[0116] In some specific implementations, along the second direction Y, the projection of the first exhaust port 30d is located within the projection of the heat exchange element 31. The first air inlet 30c is connected to the heat exchange element 31 through the first channel 30a, and the first exhaust port 30d is connected to the heat exchange element 31. Under the external circulation of the heat exchanger 30, the first gas G1 passes through the first air inlet 30c, the first channel 30a and the heat exchange element 31 in sequence and is discharged from the housing 10 from the first exhaust port 30d. The flow path length of the first gas G1 is short, which improves the heat exchange efficiency of the heat exchanger 30.

[0117] Please return to Figure 6b In some embodiments, the first channel 30a guides the first gas G1 to be discharged from the first exhaust port 30d and away from the first air inlet 30c, and the angle α between the discharge direction of the first gas G1 and the first direction X is an acute angle. With this arrangement, on the one hand, the discharge of the first gas G1 is less hindered by the inner wall of the outer shell 322, and the discharge path of the first gas G1 is relatively smooth; on the other hand, the discharge direction of the first gas G1 is inclined outward, and the first gas G1 is further away from the energy storage device after being discharged, so that the total amount of high-temperature gas falling back to the first air inlet 30c is reduced, and the external circulation cooling effect of the energy storage device is further improved.

[0118] In some specific implementations, α is one of 10°, 15°, 20°, 24°, 28°, 32°, 36°, 38°, 40°, 45°, 48°, 65°, 72°, 76°, 78°, 80°, 85°, and the range between any two of the angles.

[0119] Please return to Figure 6a-6d In some embodiments, the heat exchanger 30 includes a first fan 33, which is electrically connected to the controller. The first fan 33 is located on a side of the heat exchange element 31 away from the plurality of battery modules 20, and along the first direction X, the first fan 33 is closer to the first air inlet 30c than the first exhaust port 30d. Placing the first fan 33 at the air inlet improves the premature formation of condensed water droplets in the box 32, reduces the risk of frost in a cooling environment, and prolongs the service life of the energy storage device.

[0120] In some specific implementations, the first fan 33 is disposed in the first chamber 32a, and the first fan 33 guides the first gas G1 to flow into the first channel 30a.

[0121] In some specific implementations, the first fan 33 is used to drive the flow of the first gas G1. When the first fan 33 is in operation, the flow of the first gas G1 into the heat exchange element 31 is accelerated. The heat exchange element 31 realizes heat exchange between the first gas G1 outside the energy storage device and the second gas G2 inside the energy storage device, thereby reducing the temperature of the second gas G2. Exemplarily, the first fan 33 includes a volute-free centrifugal fan, which reduces the volume and weight of the first fan 33.

[0122] Alternatively, in some other embodiments, the first fan 33 is arranged inside the housing 10 or outside the housing 10, as long as the first fan 33 is used to drive the first gas G1 to flow.

[0123] Please combine Figure 8 and Figure 3 See also Figure 6b In some embodiments, the heat exchanger 30 includes a second air inlet 30e and a second air outlet 30f, the second channel 30b connects the second air inlet 30e with the second air outlet 30f, and the second air outlet 30f and the second air inlet 30e are both connected to the interior of the housing 10.

[0124] In some embodiments, the second air inlet 30e, the second air outlet 30f, and the second channel 30b are located on a side of the heat exchange element 31 close to the plurality of battery modules 20. Along the first direction X, the second air outlet 30f is farther away from the first wall 11 than the second air inlet 30e. Under the internal circulation of the heat exchanger 30, after the second air inlet 30e inhales the second gas G2 with a higher temperature, the second gas G2 exchanges heat with the first gas G1 through the heat exchange element 31, and is converted into the second gas G2 with a lower temperature and discharged from the second air outlet 30f.

[0125] In some embodiments, the second air inlet 30e and the second air outlet 30f are both disposed in the inner shell 321. Along the first direction X, the second air inlet 30e is adjacent to the end wall of the heat exchange element 31 close to the second channel 30b. Along the second direction Y, the projection of the second air outlet 30f at least partially overlaps with the projection of the heat exchange element 31.

[0126] In some specific implementations, along the second direction Y, the projection of the second exhaust port 30f is located within the projection of the heat exchange element 31. The second air inlet 30e is connected to the heat exchange element 31 through the second channel 30b, and the second exhaust port 30f is connected to the heat exchange element 31. Under the internal circulation of the heat exchanger 30, the second gas G2 passes through the second air inlet 30e, the second channel 30b and the heat exchange element 31 in sequence and is discharged from the first exhaust port 30d, and flows in the second gap 1c, the plurality of fourth gaps 1b, the third gap 1d and the first gap 1a. The plurality of flow paths of the second gas G2 are parallel, which accelerates the heat dissipation of the plurality of battery modules 20 and improves the heat exchange efficiency of the heat exchanger 30.

[0127] Please return to Figure 6b In some embodiments, the second channel 30b guides the second gas G2 to be discharged from the second exhaust port 30f and away from the second air inlet 30e, and the included angle β between the discharge direction of the second gas G2 and the first direction X is an obtuse angle. In this way, the discharge of the second gas G2 is less hindered by the inner shell 321, and the discharge path of the second gas G2 is relatively smooth.

[0128] In some specific implementations, β is one of 100°, 115°, 120°, 124°, 128°, 132°, 136°, 138°, 140°, 145°, 148°, 165°, 172°, 176°, 178°, and the range between any two of the angles.

[0129] Please return to Figure 6a-6dIn some embodiments, the heat exchanger 30 includes a second fan 34, which is electrically connected to the controller. The second fan 34 is used to drive the second gas G2 to flow. The second fan 34 is located on a side of the heat exchange element 31 close to the plurality of battery modules 20. Along the first direction X, the second fan 34 is closer to the second air inlet 30e than the second exhaust port 30f. The second fan 34 is arranged at the exhaust position. When the second fan 34 is in working state, the first gas G1 is accelerated to enter the heat exchanger 30, thereby improving the heat exchange efficiency. Exemplarily, the second fan 34 includes a volute-free centrifugal fan, which reduces the volume and weight of the second fan 34.

[0130] In some specific implementations, the second fan 34 is disposed in the second chamber 32b, and the second fan 34 guides the second gas G2 to flow into the second channel 30b.

[0131] Alternatively, in some other embodiments, the second fan 34 is arranged inside the housing 10 or outside the housing 10, as long as the second fan 34 is used to drive the second gas G2 to flow.

[0132] Please combine Figure 6b-6d See also Figure 2 or Figure 3 In some embodiments, the energy storage device includes a pipeline 90. The pipeline 90 extends from the first gap 1a to the heat exchanger 30 and is connected to the heat exchanger 30. The pipeline 90 connects the second air inlet 30e with the first gap 1a.

[0133] In some specific implementations, one end of the pipe 90 is fixed to the inner shell 321. Along the second direction Y, the projection of the second gas inlet 30e is located within the projection of the pipe 90. The other end of the pipe 90 covers one side of the first gap 1a, so that the second gas G2 unidirectionally circulates in the plurality of fourth gaps 1b, the third gap 1d, the first gap 1a, the pipe 90, the heat exchanger 30, and the second gap 1c.

[0134] In the present application, the arrangement of the pipeline 90 allows the first gas G1 to flow unidirectionally in the housing 10 , thereby reducing the flow resistance of backflow and / or mixed flow and improving the heat exchange efficiency of the heat exchanger 30 .

[0135] Fig.10 for Figure 2 The schematic diagram of the structure of the battery module of the energy storage device shown is as follows: Fig.10As shown, in some embodiments, the battery module 20 includes a plurality of battery cells 21 arranged along the second direction Y. Along the second direction Y, the battery module 20 includes a first end 201 and a second end 202. The thermal resistance between the battery cell 21 and the first end 201 is greater than the thermal resistance between the battery cell 21 and the second end 202. The thermal resistance between the battery cell 21 and the first end 201 represents: when the battery module 20 is in operation (charging or discharging), the heat generated by the plurality of battery cells 21 is conducted to the first end 201. The thermal resistance between the battery cell 21 and the second end 202 represents: when the battery module 20 is in operation (charging or discharging), the heat generated by the plurality of battery cells 21 is conducted to the second end 202.

[0136] In some embodiments, the first end 201 is an end of the battery module 20 close to the heat exchanger 30 , and the second end 202 is an end of the battery module 20 away from the heat exchanger 30 .

[0137] In the present application, the heat exchanger 30 is arranged on the second wall 12. Along the second direction Y, the temperature of the partial area of ​​the housing 10 close to the heat exchanger 30 is relatively low, while the temperature of the partial area of ​​the housing 10 far from the heat exchanger 30 is relatively high. This is reflected in the single battery module 20, where the temperature of the first end 201 is relatively low and the temperature of the second end 202 is relatively high. While reducing the heat dissipation capacity of the first end 201, the heat dissipation capacity of the second end 202 is increased, the temperature difference of each battery cell 21 arranged along the second direction Y is balanced, the temperature consistency of the battery cells is improved, and the service life of the battery module 20 is extended.

[0138] like Fig.11 As shown, in some embodiments, the battery module 20 includes a top wall 221 and a bottom wall 222. Along the first direction X, the bottom wall 222, the plurality of battery cells 21 and the bottom wall 222 are arranged in an array, and the plurality of battery cells 21 are located between the bottom wall 222 and the top wall 221. The top wall 221 and the bottom wall 222 each include a first portion 2201 close to one end of the heat exchanger 30 and a second portion 2202 away from one end of the heat exchanger 30. Along the first direction X, the spacing L3 between the first portion 2201 and the battery cell 21 is greater than the spacing L4 between the second portion 2202 and the battery cell 21. Exemplarily, the second portion 2202 includes a recess 22021. Along the first direction X, the spacing L3 between the first portion 2201 and the battery cell 21 is greater than the spacing L4 between the recess 22021 and the battery cell 21.

[0139] In some optional embodiments, the battery module 20 includes an elastic member 24, and the elastic member 24 is disposed between the first part 2201 and the battery cell 21. When the battery cell 21 expands, the elastic member 24 absorbs the expansion force of the battery cell 21, reducing the expansion force on the first part 2201. As such an elastic member 24, at least one of foam, polyurethane, epoxy resin, aerogel, and foam can be listed. Exemplarily, the elastic member 24 includes foam, and the thermal conductivity of the foam is less than 0.5W / m·K, which reduces the heat exchange between the battery cell 21 and the first part 2201.

[0140] In some optional embodiments, the battery module 20 includes a thermally conductive adhesive 25 disposed between the second portion 2202 and the battery cell 21. The thermal conductivity of the thermally conductive adhesive 25 is greater than 0.5 W / m·K, which facilitates heat exchange between the battery cell 21 and the second portion 2202.

[0141] In order to enable those skilled in the art to realize or use the present application content, description herein is provided. For those skilled in the art, various modifications to the application are apparent, and without departing from the scope of the application, the overall away from defined herein can be applied to other deformations. Therefore, the content of the application is not limited to the examples and designs described herein, but is given the widest range consistent with the away from and novel features disclosed herein.

Claims

1. An energy storage device, characterized in that: include: a housing comprising a first wall and a second wall; A plurality of battery modules are disposed in the housing, and the plurality of battery modules and the first wall are arranged along a first direction; a heat exchanger fixed to the second wall, the heat exchanger comprising a heat exchange element, the heat exchange element being configured so that the gas inside the shell exchanges heat with the gas outside the shell through the heat exchange element; The heat exchanger comprises a first air inlet, a first air outlet and a first channel, wherein the first air inlet and the first air outlet are located on a side of the heat exchanger away from the plurality of battery modules, and along the first direction, the first air outlet is closer to the first wall than the first air inlet; The first passage connects the first air inlet with the first air outlet, and both the first air outlet and the first air inlet are connected with the outside of the housing.

2. The energy storage device according to claim 1, characterized in that: The first channel is configured to guide the first gas to be discharged from the first exhaust port and away from the first inlet port, and the angle between the exhaust direction of the first gas and the first direction is an acute angle; The first gas is defined as the gas entering the heat exchanger from outside the shell.

3. The energy storage device according to claim 1 or 2, characterized in that: The heat exchanger comprises a box body and a first fan; The box is fixed to the second wall, the heat exchange element is arranged in the box, and the first fan is arranged on a side of the heat exchanger away from the plurality of battery modules; Wherein, along the first direction, the first fan is closer to the first air inlet than the first air outlet.

4. The energy storage device according to claim 3, characterized in that: The heat exchanger includes a second fan, a second air inlet, a second air outlet and a second channel; The second channel is separated from the first channel, the second channel connects the second air inlet and the second air outlet, and the second air inlet and the second air outlet are both connected to the interior of the housing; The second fan, the second air inlet and the second air outlet are arranged on a side of the heat exchanger close to the plurality of battery modules; Along the first direction, the second exhaust port is farther away from the first wall than the second air inlet port, and the second fan is closer to the second air inlet port than the second exhaust port.

5. The energy storage device according to claim 4, characterized in that: The second channel is configured to guide the second gas to be discharged from the second exhaust port and away from the second gas inlet port, and the included angle between the discharge direction of the second gas and the first direction is an obtuse angle; The second gas is defined as the gas located inside the shell.

6. The energy storage device according to claim 4 or 5, characterized in that: The housing comprises a third wall, and along a second direction perpendicular to the first direction, the second wall, the plurality of battery modules and the third wall are arranged at intervals; The energy storage device comprises a first gap, a second gap, a third gap and a fourth gap; Wherein, the first gap is located between the first wall and the plurality of battery modules, the second gap is located between the second wall and the plurality of battery modules, and the third gap is located between the third wall and the plurality of battery modules; Along the first direction, a plurality of the battery modules are arranged at intervals, and the fourth gap is located between the adjacent and spaced battery modules; The first fan is configured to drive the first gas to enter the heat exchanger from the first air inlet and be discharged from the first exhaust port; The second fan is configured to drive the second gas to enter the heat exchanger from the second air inlet and be discharged from the second air outlet to flow in the second gap, the fourth gap, the third gap and the first gap; The first gas is defined as the gas entering the heat exchanger from outside the housing; The second gas is defined as the gas located inside the shell.

7. The energy storage device according to claim 6, characterized in that: The battery module includes a plurality of battery cells, and the plurality of battery cells are arranged along a second direction perpendicular to the first direction; Along the second direction, the battery module includes a first end and a second end, and the thermal resistance between the battery cell and the first end is greater than the thermal resistance between the battery cell and the second end; The first end is defined as an end of the battery module close to the heat exchanger, and the second end is defined as an end of the battery module away from the heat exchanger.

8. The energy storage device according to claim 7, characterized in that: The battery module comprises a top wall and a bottom wall, and the plurality of battery cells are located between the top wall and the bottom wall; The top wall and the bottom wall each include a first portion close to one end of the heat exchanger and a second portion away from one end of the heat exchanger, and along the first direction, a distance between the first portion and the battery cell is greater than a distance between the second portion and the battery cell.

9. The energy storage device according to claim 8, characterized in that: The second portion includes a recess; Along the first direction, a distance between the first portion and the battery cell is greater than a distance between the recess and the battery cell.

10. The energy storage device according to claim 8, characterized in that: The battery module comprises an elastic member, wherein the elastic member is arranged between the first portion and the battery core; and / or, The battery module includes a thermally conductive adhesive, and the thermally conductive adhesive is arranged between the second part and the battery core.

11. The energy storage device according to claim 10, characterized in that: The elastic member includes foam.

12. The energy storage device according to any one of claims 6 to 11, characterized in that: The number of the battery modules is N1, and the N1 battery modules are divided into M1 battery module sets, and two adjacent battery module sets share one Battery module; Wherein, M1 and N1 satisfy: 2≤M1<N1, N1 is a positive integer greater than or equal to 3; Each of the battery module sets includes at least two battery modules, and along the first direction, the adjacent battery modules of each battery module set are arranged at intervals to form the fourth gap; The M2-th battery module set to the M3-th battery module set are arranged along the first direction, and the fourth gap between adjacent battery modules in the M3-th battery module set is greater than the fourth gap between adjacent battery modules in the M2-th battery module set; Among them, M1, M2 and M3 satisfy: 1≤M2<M3≤M1, and M1, M2 and M3 are all positive integers.

13. The energy storage device according to claim 12, characterized in that: The energy storage device meets one of the following conditions: (1) Along the first direction, the fourth gaps between adjacent battery modules in the N1 battery modules gradually increase; (2) When 2<M1<N1, the fourth gaps between adjacent battery modules in each battery module set are equal; (3) When M1=2, the two battery module sets include a first battery module set and a second battery module set. The first battery module set and the second battery module set are arranged along the first direction. The first battery module set includes N2 Battery modules, wherein the second battery module set includes N3 battery modules; In the first battery module to the N2th battery module, the fourth gap between adjacent battery modules is L1 mm, and in the N2th battery module to the N3th battery module, the fourth gap between adjacent battery modules is L2 mm; Among them, N1, N2, and N3 satisfy: N2+N3=N1, N2 and N3 are both positive integers; and L1 and L2 satisfy: L1<L2.

14. The energy storage device according to claim 13, characterized in that: 5≤L1≤20; and / or, L1≤5×K1≤L2≤20×K2; among them, 1.2≤K1≤1.5, 1.2≤K2≤1.

5.

15. The energy storage device according to any one of claims 6 to 13, characterized in that: The energy storage device comprises a windshield, which is arranged in the third gap and inclined relative to the third wall; Along the first direction, the wind shield includes a third end and a fourth end, and the third end is farther away from the third wall than the fourth end.

16. The energy storage device according to any one of claims 6 to 14, characterized in that: The energy storage device includes a pipeline; The pipe extends from the first gap toward the heat exchanger and is connected to the heat exchanger, and the pipe connects the second air inlet with the first gap.

17. The energy storage device according to claim 16, characterized in that: The energy storage device includes a pressure relief portion, which is disposed on the first wall and is configured to discharge the second gas through the second gap.

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