Battery device, energy storage system and electric device

Abstract

The application relates to a battery device, an energy storage system and a power utilization equipment, and relates to the technical field of energy storage. The battery device comprises a box body, battery monomers and an integrated busbar. The box body is internally provided with a containing cavity used for containing immersion liquid. At least two battery monomers are arranged in the containing cavity in a first direction. Adjacent two battery monomers are provided with a spacing space. The integrated busbar is arranged in the containing cavity and above the battery monomers. The integrated busbar comprises a supporting plate provided with a liquid through hole penetrating in an up-down direction. The liquid through hole is above the spacing space and communicates with the spacing space. The battery device, the energy storage system and the power utilization equipment have the advantage of relatively high heat dissipation efficiency.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a battery device, energy storage system and electrical equipment. Background Technology

[0002] In related technologies, the battery device includes multiple individual battery cells, which can be charged or discharged. During charging or discharging, heat is generated inside the battery cells, causing their temperature to rise. The battery devices in these technologies also include heat dissipation structures to transfer the heat generated by the battery cells to the outside of the battery device, keeping the battery cell temperatures within their normal operating temperature range. However, the heat dissipation efficiency of these battery devices needs further improvement. Summary of the Invention

[0003] This application provides a battery device, energy storage system, and electrical equipment, which has the advantage of relatively high heat dissipation efficiency.

[0004] In a first aspect, this application provides a battery device, which includes a housing, battery cells, and an integrated busbar. The housing has a receiving cavity for containing immersion liquid. At least two battery cells are spaced apart in the receiving cavity along a first direction, and a gap space is provided between adjacent battery cells. The integrated busbar is disposed in the receiving cavity and is located above the battery cells. The integrated busbar includes a support plate, which has a liquid passage hole extending in a vertical direction. The liquid passage hole is located above the gap space and communicates with the gap space.

[0005] When a battery cell generates heat and its temperature exceeds that of the immersion fluid, the immersion fluid absorbs this heat, ensuring that the actual temperature of the battery cell does not exceed the upper limit of the preset normal operating temperature range, thus allowing the battery cell to operate normally. The immersion fluid located in the spacer compartment is closer to the battery cell than the immersion fluid located in the through-hole. The temperature of the immersion fluid in the spacer compartment is higher than that in the through-hole. Correspondingly, the temperature of the immersion fluid in the through-hole is also higher than that of the immersion fluid further away from the battery cell. Under this temperature gradient, heat can be transferred from the immersion fluid in the spacer compartment to the immersion fluid in the through-hole, and subsequently from the immersion fluid in the through-hole to the immersion fluid further away from the battery cell. In addition, the immersion liquid with a relatively high temperature has a relatively low density. The immersion liquid with a relatively low density tends to float. The floating immersion liquid can carry heat from the space to the liquid passage hole. Then, the floating immersion liquid can carry heat from the liquid passage hole to the area above the integrated busbar. That is, heat convection is used to transfer heat from the space to the liquid passage hole more quickly, and heat convection is used to transfer heat from the liquid passage hole to the area above the integrated busbar more quickly.

[0006] Compared with related technologies, the battery device of this application has the following advantages: through the above-mentioned structural arrangement of the space and liquid passage, the heat located in the space can not only be transferred upward, but also the buoyancy generated by the relatively high temperature immersion liquid can be used to make the heat transfer upward more quickly, thereby making the heat dissipation efficiency of the battery device of this application relatively high.

[0007] Optionally, the liquid passage has a dimension W1 along the first direction, and the spacer has a dimension G1 along the first direction, wherein the ratio of dimension W1 to dimension G1 is in the range of 0.5 to 2.

[0008] Optionally, the liquid passage has a dimension L1 along the second direction, and the spacer has a dimension D1 along the second direction. Each pair of directions among the first direction, the second direction, and the up and down direction is perpendicular to each other, and the ratio of dimension L1 to dimension D1 is in the range of 0.6 to 0.8.

[0009] Optionally, the battery device further includes a separator, with at least two spaced-apart separators provided in the same space, and a first flow channel provided between the two spaced-apart separators. The extension direction of the first flow channel is parallel to the vertical direction, and the first flow channel is in communication with the liquid passage.

[0010] Optionally, the first flow channel includes a converging section and an expanding section connected to each other. The converging section is located below the expanding section. The cross-sectional area of ​​the converging section perpendicular to the vertical direction decreases from bottom to top, while the cross-sectional area of ​​the expanding section perpendicular to the vertical direction increases from bottom to top. A partition located on at least one side of the first flow channel is provided with a second flow channel. The overall height of the second flow channel is lower than the overall height of the expanding section. The first end of the second flow channel is connected to the connection between the converging section and the expanding section, and the second end of the second flow channel is connected to the space outside the partition.

[0011] Optionally, the extension direction of the second flow channel is perpendicular to the extension direction of the contraction section, or the angle between the extension direction of the second flow channel and the extension direction of the contraction section is an acute angle.

[0012] Optionally, the housing is provided with a cavity inlet, which is connected to the receiving cavity, and the inlet of the contraction section away from the expansion section is located above the cavity inlet.

[0013] Optionally, the divider is integrally formed with the tray or is detachably connected.

[0014] Optionally, the battery device also includes a flow guide tube located above the liquid inlet, and the flow guide tube has a cavity extending in the vertical direction, with the bottom of the cavity communicating with the liquid inlet.

[0015] Optionally, the area of ​​the cross-section of the lumen perpendicular to the vertical direction gradually decreases from bottom to top.

[0016] Optionally, the guide tube and the tray are integrally formed or detachably connected.

[0017] Optionally, the tray includes a tray body and at least two spaced-apart support portions. The support portions extend downward from the lower surface of the tray body to the top wall of the battery cell. A third flow channel is provided between the two spaced-apart support portions. The third flow channel extends along a first direction and is connected to the liquid passage and the spacer space.

[0018] Optionally, a fourth flow channel is recessed on the lower surface of the tray, the fourth flow channel extends along the first direction, and the fourth flow channel, the liquid passage hole and the spacer are connected.

[0019] Secondly, this application provides an energy storage system that includes the battery device described above. Accordingly, the energy storage system may also include the technical effects of the battery device described above, which will not be repeated here.

[0020] Thirdly, this application provides an electrical device that includes the energy storage system described above. The electrical device can be a tram, a power grid, a household appliance, etc. Accordingly, the electrical device may also include the technical effects of the battery device described above, which will not be repeated here.

[0021] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a cross-sectional view of the battery device in one embodiment;

[0024] Figure 2 This is a three-dimensional structural diagram of a single battery cell in one embodiment;

[0025] Figure 3 A three-dimensional structural schematic diagram of an integrated busbar in one embodiment;

[0026] Figure 4 for Figure 3 A schematic diagram of the structure of the center support plate from a top-down view;

[0027] Figure 5 This is a schematic diagram of the assembly structure integrating the busbar and multiple battery cells;

[0028] Figure 6 This is a cross-sectional view of the battery device in another embodiment;

[0029] Figure 7 This is a schematic diagram of the assembly structure of the heat pipe and the support plate;

[0030] Figure 8 A schematic diagram showing the dimensions of the first projection of the liquid passage and the second projection of the spacer.

[0031] Figure 9 This is a schematic diagram of the battery cell and separator from a top-down view.

[0032] Figure 10 This is a schematic diagram of the assembly structure of the battery cell, separator, and tray;

[0033] Figure 11 This is a schematic diagram of the structure of a battery cell and separator in another embodiment;

[0034] Figure 12 This is a schematic diagram of the battery cell, separator, and extension tube in another embodiment;

[0035] Figure 13 This is a schematic diagram of the extension tube, side structural wall, and fins in another embodiment;

[0036] Figure 14 This is a schematic diagram of the structure of a battery cell and separator in yet another embodiment;

[0037] Figure 15 This is a schematic diagram of the structure of the battery cell, separator, and housing in other embodiments;

[0038] Figure 16 This is a schematic diagram of the structure of a battery cell and a separator in yet another embodiment;

[0039] Figure 17 This is a schematic diagram of the structure of the tray and the guide tube in one embodiment;

[0040] Figure 18 This is a schematic diagram showing the distribution of explosion-proof holes and liquid passage holes in one embodiment;

[0041] Figure 19 This is a schematic diagram showing the distribution of explosion-proof holes and liquid passage holes in another embodiment;

[0042] Figure 20 This is a schematic diagram of the assembly structure of the battery cell, separator, and tray in another embodiment;

[0043] Figure 21 This is a schematic diagram showing the flow direction of the immersion liquid;

[0044] Figure 22This is a schematic diagram of the assembly structure of the battery cell, separator, and tray in another embodiment.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1-Box body, 11-Receiving cavity, 12-Bottom structural wall, 121-Cavity inlet, 13-Top structural wall, 131-Cavity outlet, 14-Side structural wall, 15-Fin, 2-Battery cell, 2a-Gap space, 21-First side wall, 22-Second side wall, 23-Top wall, 24-Bottom wall, 25-Positive terminal, 26-Negative terminal, 27-Explosion-proof valve, 3-Integrated busbar, 31-Pattern, 311-Terminal hole, 312-Explosion-proof hole 313-Liquid passage, 314-Plate body, 315-Support, 32-Bar plate, 4-Separator, 41-First separator, 42-Second separator, 43-First flow channel, 431-Contraction section, 431a-Liquid inlet, 432-Expansion section, 44-Second flow channel, 441-First end, 442-Second end, 45-Break current section, 5-Third flow channel, 6-Fourth flow channel, 7-Extension pipe, 8-Guide pipe, 81-Cavity, 9-Heat pipe. Detailed Implementation

[0047] To better understand the technical solutions of this application, the embodiments of this application are described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are merely some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application. The terminology used in the embodiments of this application is for the purpose of describing specific embodiments only, and is not intended to limit this application. The singular forms "a," "described," and "the" used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should be understood that the term "and / or" used herein is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0048] In the first aspect, this application provides some embodiments of battery devices, relating to the field of energy storage technology.

[0049] In some embodiments, the battery device may include a front-back direction, a left-right direction, and a top-down direction (also referred to as a height direction), wherein every two of the front-back, left-right, and top-down directions are perpendicular to each other. The front-back direction may also be a first direction, the left-right direction may be a second direction, and the top-down direction may be a third direction.

[0050] In some embodiments, please refer to Figure 1 As shown, the battery device may include a housing 1, battery cells 2, and integrated busbars 3. The housing 1 is provided with a receiving cavity 11, and both the battery cells 2 and the integrated busbars 3 can be disposed within the receiving cavity 11.

[0051] In some embodiments, the battery cell 2 may be a secondary battery (also known as a rechargeable battery or a storage battery), which is a battery that can be recharged after discharge to reactivate the active materials and thus restore electrical energy. The battery device includes at least two battery cells 2, and the electrical connection between the at least two battery cells 2 may be in series, parallel, or mixed connection, wherein mixed connection includes series and parallel connection.

[0052] In some embodiments, please refer to Figure 2 As shown, the battery cell 2 may include two first sidewalls 21 arranged back-to-back in the front-to-back direction, two second sidewalls 22 arranged back-to-back in the left-to-right direction, and a top wall 23 and a bottom wall 24 arranged back-to-back in the vertical direction. The battery cell 2 may also include a positive terminal 25, a negative terminal 26, and an explosion-proof valve 27 disposed on the top wall 23. Both the positive terminal 25 and the negative terminal 26 can be electrically connected to an external circuit located outside the battery cell 2, so that the battery cell 2 can release electrical energy to the external circuit, or obtain electrical energy from the external circuit.

[0053] In some embodiments, please refer to Figure 3 As shown, the integrated busbar 3 may include a tray 31 and multiple trays 32. The tray 31 is provided with multiple tray slots, and each tray slot is fitted with a corresponding tray 32. Please refer to... Figure 4 As shown, the tray 31 is also provided with multiple through-holes 311 running vertically, and some plate slots may have two through-holes 311. Please refer to... Figure 5 As shown, the integrated busbar 3 can be disposed above at least two battery cells 2. Within the same taper slot, one terminal hole 311 can be penetrated by the positive terminal 25 of one battery cell 2, and the other terminal hole 311 can be penetrated by the negative terminal 26 of another battery cell 2. The positive terminal 25 and the negative terminal 26 can be electrically connected by a taper 32 to connect the two battery cells 2 in series.

[0054] In some embodiments, please refer to Figure 4As shown, the tray 31 can also be provided with multiple explosion-proof holes 312. Each explosion-proof hole 312 is located above the explosion-proof valve 27 of the corresponding battery cell 2. When the internal pressure of the battery cell 2 increases and exceeds the upper limit, the gas inside the battery cell 2 can be discharged to the outside through the explosion-proof valve 27. The discharged gas can be discharged through the explosion-proof hole 312 so that the discharged gas can be quickly diffused, thereby reducing the possibility of the battery cell 2 exploding.

[0055] In some embodiments, the integrated busbar 3 (Cells Contact System, CCS) may also be referred to as a signal acquisition component. The integrated busbar 3 can acquire operating signals that reflect the charging and discharging state of the battery cells 2, such as current signals, voltage signals, and temperature signals. The integrated busbar 3 can transmit the acquired operating signals to the Battery Manager Unit (BMU) or the Battery Management System (BMS).

[0056] In some embodiments, the integrated busbar 3 may include multiple cables (not shown in the figure), and each cable may have a data acquisition unit at its end. Each data acquisition unit may be located on a corresponding busbar 32 and used to acquire working signals.

[0057] In some other embodiments, the integrated busbar 3 may include a flexible printed circuit board (FPC), which (not shown in the figure) may also be provided with multiple acquisition units, each of which may be located on a corresponding panel 32 and used to acquire working signals.

[0058] In some other embodiments, the integrated busbar 3 may include a printed circuit board (PCB), which (not shown in the figure) may also be provided with multiple acquisition units, each of which may be located on a corresponding busbar 32 and used to acquire working signals.

[0059] In some embodiments, please refer to Figure 1 As shown, the housing 11 of the casing 1 can also contain an immersion liquid (not shown in the figure). The immersion liquid can exchange heat with the battery cell 2 to keep the temperature of the battery cell 2 within a set temperature range. The type of immersion liquid can include single-phase immersion liquid and two-phase immersion liquid. Single-phase immersion liquid can include mineral oil, silicone oil, and fluorinated liquid (e.g., 3M). TM Novec TM Two-phase immersion solutions can include 7200 / 7500, synthetic esters, or other types of non-phase-change immersion solutions. Two-phase immersion solutions can include low-boiling-point fluorinated solutions (e.g., 3M). TM Novec TM7100 / 7200) or other types of boiling phase-change immersion liquids.

[0060] In some embodiments, please refer to Figure 1 As shown, at least two battery cells 2 can be spaced apart in the receiving cavity 11 along the front-to-back direction, and adjacent battery cells 2 can have the following spacing: Figure 5 The space 2a shown can also contain immersion liquid, and the sidewalls (e.g., the first sidewall 21) of two adjacent battery cells 2 facing each other can exchange heat with the immersion liquid located in the space 2a.

[0061] In some embodiments, please refer to Figure 4 As shown, the tray 31 can be provided with multiple liquid passage holes 313 extending vertically. Each liquid passage hole 313 can be located above the corresponding space 2a, and each liquid passage hole 313 can communicate with the corresponding space 2a. It can be understood that the immersion liquid can also be located within the liquid passage hole 313.

[0062] As described above, when battery cell 2 generates heat and its temperature is higher than that of the immersion liquid, the immersion liquid can absorb the heat from battery cell 2, ensuring that the actual temperature of battery cell 2 does not exceed the upper limit of the preset normal operating temperature range, thus allowing battery cell 2 to operate normally. The immersion liquid located in the space 2a is closer to battery cell 2 than the immersion liquid located in the liquid passage 313. The temperature of the immersion liquid in space 2a is higher than that in the liquid passage 313. Correspondingly, the temperature of the immersion liquid in the liquid passage 313 is also higher than that of the immersion liquid further away from battery cell 2. Under this temperature gradient, heat can be transferred from the immersion liquid in space 2a to the immersion liquid in the liquid passage 313, and subsequently, heat can be transferred from the immersion liquid in the liquid passage 313 to the immersion liquid further away from battery cell 2. Furthermore, the immersion liquid with a relatively high temperature has a relatively low density, and the relatively low density immersion liquid tends to float. The floating immersion liquid can carry heat from the space 2a upward to the liquid passage 313, and then the floating immersion liquid can carry heat from the liquid passage 313 upward to the area above the integrated busbar 3. That is, heat convection is used to make heat transfer from the space 2a to the liquid passage 313 more quickly, and heat convection is used to make heat transfer from the liquid passage 313 to the area above the integrated busbar 3 more quickly.

[0063] Therefore, compared with related technologies, some embodiments of the battery device in this application have the following advantages: through the above-described structural arrangement of the space 2a and the liquid passage 313, the heat located in the space 2a can not only be transferred upward, but also the buoyancy generated by the relatively high temperature immersion liquid can be used to make the heat transfer upward faster, thereby making the heat dissipation efficiency of some embodiments of the battery device in this application relatively high.

[0064] In some embodiments, when the type of immersion liquid is a two-phase immersion liquid, the immersion liquid located in the space 2a undergoes a phase change after absorbing the heat of the battery cell 2, changing from a liquid state to a gas state. The density of the gas is lower than that of the liquid, and the gas has a tendency to float upward. The gas carrying heat can quickly transfer from the space 2a to the liquid passage 313, and then the gas carrying heat can quickly transfer from the liquid passage 313 to the area above the integrated busbar 3.

[0065] In some embodiments, please refer to Figure 6 As shown, the battery device may further include a heat pipe 9, which passes through the top cover of the housing 1. The lower part of the heat pipe 9 can contact the immersion liquid located above the integrated busbar 3, and the upper part of the heat pipe 9 can be located above the housing 1. The part of the heat pipe 9 that contacts the immersion liquid can serve as a heat absorption part, and the part of the heat pipe 9 located outside the housing 1 can serve as a heat dissipation part. Therefore, the heat pipe 9 can absorb heat from the immersion liquid and transfer the absorbed heat to the outside of the housing 1. In this configuration, the temperature of the immersion liquid above the integrated busbar 3 is reliably lower than the temperature of the immersion liquid below the integrated busbar 3, that is, a temperature gradient with decreasing temperature from bottom to top is reliably formed, and heat can be quickly and reliably transferred from the space 2a to the heat pipe 9 through the liquid passage 313.

[0066] In some embodiments, please refer to Figure 7 As shown, the battery device may include multiple heat pipes 9 spaced apart in the front-to-back direction. The bottom of each heat pipe 9 can be inserted into a corresponding liquid passage 313 so that heat can be quickly and reliably transferred from the space 2a to the heat pipe 9 through the liquid passage 313.

[0067] In some other embodiments (not shown in the figures), the battery device may include a plurality of heat pipes spaced apart in the front-to-back direction, wherein the bottom of each heat pipe may not be inserted into the corresponding liquid passage, but the bottom of each heat pipe may be located above the corresponding liquid passage.

[0068] In some other embodiments, the battery device may also not include a heat pipe.

[0069] In some embodiments, the liquid passage 313 may have a dimension W1 in the front-to-back direction, and the spacer 2a may have a dimension G1 in the front-to-back direction. Please refer to... Figure 8As shown, if the area of ​​the liquid passage 313 projected onto the support plate 31 in the vertical direction is the first projection S1, and the area of ​​the gap space 2a projected onto the support plate 31 in the vertical direction is the second projection S2, then the first projection S1 can also have a dimension W1 in the front-back direction, and the second projection S2 can also have a dimension G1 in the front-back direction. The ratio of dimension W1 to dimension G1 can be in the range of 0.5 to 1. Specifically, the ratio of dimension W1 to dimension G1 can be 0.5, 0.6, 0.7, 0.8, 0.9, or 1.

[0070] In some other embodiments (not shown in the figures), the ratio of dimension W1 to dimension G1 may also be in the range of 1 to 2. Specifically, the ratio of dimension W1 to dimension G1 may be 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.

[0071] In some embodiments, the dimension W1 of the liquid passage 313 along the front-to-back direction can be in the range of 1.5mm to 2mm, and the dimension W1 can specifically be 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2mm.

[0072] In some embodiments, the liquid passage 313 may have a dimension L1 in the left-right direction, and the spacer 2a may have a dimension D1 in the left-right direction. Please refer to... Figure 8 As shown, if the area of ​​the liquid passage 313 projected onto the support plate 31 in the vertical direction is the first projection S1, and the area of ​​the space 2a projected onto the support plate 31 in the vertical direction is the second projection S2, then the first projection S1 can also have a dimension L1 in the horizontal direction, and the second projection S2 can also have a dimension D1 in the horizontal direction. The ratio of dimension L1 to dimension D1 can be in the range of 0.6 to 0.8, and the ratio of dimension W1 to dimension G1 can specifically be 0.6, 0.65, 0.7, 0.75, or 0.8.

[0073] In some embodiments, the dimension L1 of the liquid passage 313 in the left-right direction can be in the range of 40mm to 90mm, and the dimension L1 can specifically be 40mm, 50mm, 60mm, 70mm, 80mm or 90mm.

[0074] With the above-mentioned settings for dimensions L1 and W1, the heat-carrying immersion liquid can smoothly flow from the space 2a through the liquid passage 313 to the area above the integrated busbar 3, thereby reliably controlling the temperature of the battery cell within the preset operating range.

[0075] In some embodiments, please refer to Figure 9As shown, the battery device may also include separators 4, and at least two separators 4 spaced apart in the same space 2a in the left-right direction may be provided. It is understood that two adjacent battery cells 2 are separated by at least two separators 4, and the separators 4 may include insulating material. The separators 4 serve to insulate and reduce the likelihood of electrical breakdown between the sidewalls of two adjacent battery cells 2.

[0076] In some embodiments, please refer to Figure 9 As shown, within the same space 2a, a first partition 41 or a second partition 42 spaced apart in the left-right direction can be provided, and a first flow channel 43 can be provided between the first partition 41 and the second partition 42. Please refer to... Figure 10 As shown, the extension direction of the first flow channel 43 is parallel to the vertical direction, and the first flow channel 43 is connected to the liquid passage hole 313. As can be seen from the above, the space within the first flow channel 43 formed by the first separator 41, the second separator 42, and the first sidewalls 21 of the two battery cells 2 facing each other is also part of the spacer space 2a. The first flow channel 43 can also contain immersion liquid, and the first flow channel 43 can guide the immersion liquid to transfer heat upward to the liquid passage hole 313 and the area above the integrated busbar 3.

[0077] In some other embodiments (not shown in the figures), three or more partitions spaced apart in the left-right direction may be provided in the same space, and correspondingly, at least two first flow channels spaced apart in the left-right direction may be provided in the same space.

[0078] In some embodiments, the immersion fluid within the receiving cavity 11 of the housing 1 may or may not circulate. The non-circulation of the immersion fluid within the receiving cavity 11 of the housing 1 primarily means that the immersion fluid within the receiving cavity 11 does not flow outside the receiving cavity 11, nor is it cooled or dissipated outside the receiving cavity 11. The circulation of the immersion fluid within the receiving cavity 11 of the housing 1 primarily means that the immersion fluid within the receiving cavity 11 can flow outside the receiving cavity 11 and then flow back inside the receiving cavity 11, and the immersion fluid can be cooled and dissipated outside the receiving cavity 11.

[0079] In some embodiments, if a drive pump and an external pipeline are provided outside the battery device, the drive pump can drive the immersion liquid that has absorbed heat in the receiving cavity 11 to flow out of the receiving cavity 11 through the external pipeline to complete the cooling and heat dissipation. The drive pump can also drive the immersion liquid that has been cooled and dissipated outside the receiving cavity 11 to flow back into the receiving cavity 11 through the external pipeline to continue absorbing the heat of the battery cell 2, thereby completing the heat dissipation cycle.

[0080] In some embodiments, if the immersion liquid located outside the immersion cavity 11 flows into the immersion cavity 11 from below, and the immersion liquid located inside the immersion cavity 11 flows out from above to outside the immersion cavity 11, the flow direction of the immersion liquid inside the immersion cavity 11 is mainly from below the immersion cavity 11 to above the immersion cavity 11.

[0081] In some embodiments, please refer to Figure 11 As shown, the first flow channel 43 may include a converging section 431 and an expanding section 432 connected to each other. The converging section 431 is located below the expanding section 432. The cross-sectional area of ​​the converging section 431 perpendicular to the vertical direction decreases from bottom to top, while the cross-sectional area of ​​the expanding section 432 perpendicular to the vertical direction increases from bottom to top. A partition 4 located on at least one side of the first flow channel 43 is provided with a second flow channel 44. The overall height of the second flow channel 44 is lower than the overall height of the expanding section 432. The first end 441 of the second flow channel 44 connects to the junction between the converging section 431 and the expanding section 432, and the second end 442 connects to the outside of the partition space 2a. Under this configuration, when the immersion liquid in the first flow channel 43 flows from bottom to top, the immersion liquid passes through the converging section 431 and the expanding section 432 in sequence. When the immersion liquid flows upward along the converging section 431, the pressure of the immersion liquid gradually increases because the cross-sectional area of ​​the converging section 431 perpendicular to the vertical direction gradually decreases. As the immersion liquid flows upward along the expansion section 432, the pressure of the immersion liquid gradually decreases as the area of ​​the cross-section perpendicular to the vertical direction of the expansion section 432 gradually increases. When the immersion liquid passes through the connection between the contraction section 431 and the expansion section 432, the immersion liquid changes from a compressed state to an expanded state. Therefore, a certain negative pressure is generated at the connection between the contraction section 431 and the expansion section 432. This negative pressure causes the immersion liquid located outside the space 2a to flow through the second flow channel 44 to the connection between the contraction section 431 and the expansion section 432, and then to the liquid passage 313 located above. With the above-mentioned arrangement of the contraction section 431 and expansion section 432 of the first flow channel 43 and the arrangement of the second flow channel 44, not only can the immersion liquid located below the battery cell 2 pass through the contraction section 431 and expansion section 432 in sequence, but also the immersion liquid on both sides of the battery cell 2 in the left and right directions can pass through the second flow channel 44 and expansion section 432 in sequence. Therefore, a relatively large amount of immersion liquid can be used to absorb the heat of the first sidewall 21 of the battery cell 2, and the heat dissipation efficiency is relatively high.

[0082] In some embodiments, please refer to Figure 11 As shown, the extension direction of the second flow channel 44 is perpendicular to the extension direction of the contraction section 431. In other words, the extension direction of the second flow channel 44 is perpendicular to the vertical direction.

[0083] In some embodiments, please refer to Figure 12As shown, the battery device may further include an extension tube 7, which can extend in the left-right direction. The second end 442 of the second flow channel 44 can be connected to the extension tube 7. The end of the extension tube 7 away from the battery cell 2 can extend to the area near the left and right side walls of the housing 1. The temperature of the immersion liquid located on the left and right sides of the battery cell 2, away from the battery cell 2 and near the left and right side walls of the housing 1, is lower than the temperature of the immersion liquid located on the left and right sides of the battery cell 2, near the battery cell 2 and away from the left and right side walls of the housing 1. The immersion liquid located on the left and right sides of the battery cell 2, away from the battery cell 2 and near the left and right side walls of the housing 1, can flow into the expansion section 432 in sequence through the extension tube 7 and the second flow channel 44. Therefore, the heat dissipation efficiency of the first side wall 21 of the battery cell 2 is relatively high.

[0084] In some embodiments, please refer to Figure 13 As shown, the housing 1 includes side structural walls 14 spaced apart in the left-right direction. The housing 1 also includes multiple fins 15, which are disposed on the side of the side structural walls 14 away from the receiving cavity 11. The end of the extension tube 7 away from the battery cell 2 can extend to the side of the side structural walls 14 near the receiving cavity 11. Because the fins 15 have a relatively large contact area with the external environment of the housing 1, their heat dissipation efficiency is relatively high. Therefore, the temperature of the immersion liquid near the side structural walls 14 in the receiving cavity 11 is relatively lower than the temperature of the immersion liquid away from the side structural walls 14. As can be seen from the above, the relatively cooler immersion liquid near the side structural walls 14 in the receiving cavity 11 can flow sequentially into the expansion section 432 through the extension tube 7 and the second flow channel 44. Therefore, the heat dissipation efficiency of the first side wall 21 of the battery cell 2 is relatively high.

[0085] In some embodiments, please refer to Figure 14 As shown, the extension direction of the second flow channel 44 can be inclined relative to the extension direction of the contraction section 431; that is, the extension direction of the second flow channel 44 can be inclined relative to the vertical direction. As mentioned above, since the overall height of the second flow channel 44 is lower than the height of the expansion section 432, the height of the first end 441 of the second flow channel 44 is higher than the height of the second end 442. Because the second end 442 is closer to the immersion liquid below the battery cell 2, a portion of the immersion liquid below the battery cell 2 can flow into the second flow channel 44 through the second end 442. Since the immersion liquid below the battery cell 2 has not yet fully absorbed heat, its temperature is relatively low. As mentioned above, the relatively low-temperature immersion liquid can flow into the expansion section 432 through the second flow channel 44, thus the heat dissipation efficiency of the first sidewall 21 of the battery cell 2 is relatively high.

[0086] In some embodiments, please refer to Figure 14As shown, the angle between the extending direction of the second flow channel 44 and the extending direction of the contraction section 431 can be an acute angle α, which can be in the range of 5° to 89°. Under this setting, the second end 442 of the second flow channel 44 is close to the lower half of the battery cell 2. The temperature of the immersion liquid on the left and right sides of the lower half of the battery cell 2 is relatively low. The relatively low-temperature immersion liquid can flow into the expansion section 432 through the second flow channel 44, so that the immersion liquid in the expansion section 432 still has a good cooling effect. Specifically, the acute angle α can be 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85° or 89°.

[0087] In some embodiments, please refer to Figure 15 As shown, the bottom structural wall 12 of the housing 1 can be provided with a cavity inlet 121, which is connected to the receiving cavity 11. The inlet 431a of the contraction section 431, away from the expansion section 432, is located above the cavity inlet 121. Under this configuration, the immersion liquid outside the receiving cavity 11 can quickly enter the contraction section 431 from the cavity inlet 121 through the inlet 431a under the drive of the pump, and then quickly enter the expansion section 432. As mentioned above, when the rapidly flowing immersion liquid passes through the connection between the contraction section 431 and the expansion section 432, a relatively large negative pressure will be generated at the connection between the contraction section 431 and the expansion section 432. This relatively large negative pressure can cause the immersion liquid on the left and right sides of the battery cell 2 to flow into the expansion section 432 through the second flow channel 44.

[0088] In some embodiments, please refer to Figure 15 As shown, the top structural wall 13 of the housing 1 can be provided with a cavity outlet 131, which is connected to the receiving cavity 11. The cavity outlet 131 can be located above the first flow channel 43 and the liquid passage 313, so that the immersion liquid passing through the first flow channel 43 and the liquid passage 313 can flow out of the receiving cavity 11 through the cavity outlet 131.

[0089] In some other embodiments (not shown in the figure), the liquid inlet of the cavity can also be located in other parts of the bottom structural wall, and the liquid outlet of the cavity can also be located in other parts of the top structural wall. The height of the liquid inlet of the cavity is lower than the height of the bottom wall of the battery cell, and the height of the liquid outlet of the cavity is higher than the height of the integrated busbar.

[0090] In some embodiments, please refer to Figure 16 As shown, two adjacent partitions 4 are provided with turbulence-disrupting parts 45 facing each other. The turbulence-disrupting parts 45 are used to disrupt the laminar flow in the immersion liquid near the partitions 4, accelerate the heat transfer rate in the immersion liquid, and thus improve the heat exchange efficiency.

[0091] The first separator 41 and the second separator 42 each have a turbulence section 45 on the part facing each other.

[0092] In addition, the spoiler 45 can be a raised structure, and the surface of the spoiler 45 can be a curved surface, which has the advantage of low resistance.

[0093] In some other embodiments (not shown in the figures), the turbulence portion may be a recessed structure.

[0094] In some embodiments, the separator 4 and the tray 31 can be integrally formed or detachably connected. In this configuration, it is convenient to assemble the separator 4 and the tray 31 first, and then assemble them with multiple battery cells 2.

[0095] The detachable connection may include snap-fit ​​or fastener connection.

[0096] In some embodiments, please refer to Figure 17 As shown, the battery device may also include a flow guide 8, which is located above the liquid inlet 313. The flow guide 8 has a cavity 81 extending vertically within it, and the bottom of the cavity 81 communicates with the liquid inlet 313. In this configuration, after the immersion liquid in the space 2a flows from bottom to top to the liquid inlet 313, it can continue to flow upwards under the guidance of the flow guide 8. This allows the immersion liquid that has absorbed heat to move away from the battery cell 2 in an upward direction, reducing the likelihood of the relatively hot immersion liquid diffusing near the top wall of the battery cell 2, thereby improving heat dissipation from the top wall of the battery cell 2.

[0097] In some embodiments, please refer to Figure 17 As shown, the area of ​​the cross section of the cavity 81 perpendicular to the vertical direction gradually decreases from bottom to top. Under this setting, when the immersion liquid in the cavity 81 flows in the direction from bottom to top, the pressure of the immersion liquid gradually increases and the flow rate of the immersion liquid gradually increases, so that the immersion liquid that has absorbed heat can flow to the area away from the top wall of the battery cell 2 more quickly, thereby allowing the top wall of the battery cell 2 to dissipate heat better.

[0098] In the embodiment of heat pipe 9 described above, the guide pipe 8 can guide the immersion liquid in the pipe cavity 81 to flow directly upward to the heat absorption part of heat pipe 9, so that the heat of the immersion liquid can be quickly absorbed by heat pipe 9.

[0099] In some embodiments, please refer to Figure 17 As shown, the guide tube 8 and the support plate 31 can be integrally formed or detachably connected.

[0100] In some embodiments, please refer to Figure 18As shown, a long strip-shaped liquid passage 313 can be provided between two adjacent explosion-proof holes 312.

[0101] In some embodiments, please refer to Figure 19 As shown, two short strip-shaped liquid passage holes 313 spaced apart in the left-right direction can be provided between two adjacent explosion-proof holes 312.

[0102] In some other embodiments (not shown in the figures), other numbers of liquid passage holes may also be provided between two adjacent explosion-proof holes.

[0103] In some other embodiments (not shown in the figure), the relationship between the number of liquid passages N on the tray and the number of battery cells M satisfies N = k(M-1), where k is a natural number greater than or equal to 2.

[0104] In some embodiments (not shown in the figures), when the integrated busbar includes a flexible circuit board, the flexible circuit board may be provided with a clearance hole or other clearance structure, the clearance hole being located above the liquid passage hole, the clearance hole being able to avoid the immersion liquid flowing out of the liquid passage hole.

[0105] In some embodiments (not shown in the figures), when the integrated busbar includes a printed circuit board, the printed circuit board may be provided with a clearance hole or other clearance structure, the clearance hole being located above the liquid passage hole, the clearance hole being able to avoid the immersion liquid flowing out of the liquid passage hole.

[0106] In some embodiments, please refer to Figure 20 As shown, the support plate 31 may include a plate body 314 and at least two spaced-apart support portions 315. The support portions 315 extend downward from the lower surface of the plate body 314 to the top wall of the battery cell 2. The top wall of the battery cell 2 supports the plate body 314 through the support portions 315. The plate body 314 may be provided with the aforementioned plate slot, electrode post hole 311, explosion-proof hole 312, and liquid passage hole 313. A third flow channel 5 may be provided between the two support portions 315. The third flow channel 5 extends in the front-rear direction and is connected to the space 2a. Alternatively, the third flow channel 5, the liquid passage hole 313, and the first flow channel 43 may be connected. In this configuration, after the immersion liquid near the top wall of the battery cell 2 absorbs heat, the heat-absorbing immersion liquid can be transferred from the third flow channel 5 to the liquid passage hole 313.

[0107] Please refer to Figure 20 As shown, the third flow channel 5 can have a height dimension H1 in the vertical direction. The height dimension H1 can be in the range of 1mm to 15mm. Specifically, the height dimension H1 can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm or 15mm.

[0108] In addition, the third flow channel 5 can also be connected to the explosion-proof hole 312 mentioned above, which runs vertically through the battery cell 2. In this configuration, the explosion-proof hole 312 connected to the third flow channel 5 can not only be used to discharge gas from inside the battery cell 2 to reduce the possibility of explosion, but also allow the immersion liquid absorbing heat from the top wall of the battery cell 2 to be transferred from the third flow channel 5 through the explosion-proof hole 312 to an area higher than the integrated busbar 3. In other words, the explosion-proof hole 312 has a multi-functional advantage. Please refer to... Figure 21 As shown, the flow direction of the immersion liquid in the space 2a can be as shown by arrow f1, the flow direction of the immersion liquid in the liquid passage 313 can be as shown by arrow f2, the flow direction of the immersion liquid in the third flow channel 5 can be as shown by arrow f3, and the flow direction of the immersion liquid in the explosion-proof hole 312 can be as shown by arrow f4.

[0109] In some embodiments, please refer to Figure 22 As shown, the lower surface of the tray 31 may be recessed to form a fourth flow channel 6, which extends in the front-to-back direction. The fourth flow channel 6, the liquid passage 313, and the spacer space 2a are connected. Alternatively, the fourth flow channel 6, the liquid passage 313, and the first flow channel 43 are connected. In this configuration, after the immersion liquid near the top wall of the battery cell 2 absorbs heat, the heat-absorbing immersion liquid can be transferred from the fourth flow channel 6 to the liquid passage 313.

[0110] Please refer to Figure 22 As shown, the fourth flow channel 6 can have a height dimension H2 along the vertical direction. The height dimension H2 can be in the range of 1mm to 15mm. Specifically, the height dimension H2 can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm or 15mm.

[0111] In addition, the fourth flow channel 6 can also be connected to the explosion-proof hole 312 that is provided vertically as mentioned above. In this configuration, the explosion hole 312 connected to the fourth flow channel 6 can not only be used to discharge the gas inside the battery cell 2 to reduce the possibility of the battery cell 2 exploding, but also allow the immersion liquid that absorbs the heat of the top wall of the battery cell 2 to be transferred from the fourth flow channel 6 through the explosion-proof hole 312 to the area above the integrated busbar 3. That is, the explosion-proof hole 312 has the advantage of multiple functions.

[0112] Secondly, this application provides some embodiments of an energy storage system, which includes an inverter, a battery management system (BMS), and at least one battery device described above.

[0113] An inverter converts direct current (DC) to alternating current (AC). Inverters offer advantages such as high conversion efficiency, fast start-up speed, and high safety, and also provide protection against short circuits, overloads, over / under voltage, and over-temperature. A battery management system (BMS) ensures the battery device operates within a safe operating range. It controls the charging and discharging power of the battery device based on factors such as ambient temperature, battery status, and power demand, improving battery safety and optimizing its operating state, thereby extending battery range and lifespan. A battery device may include a battery management unit (BMU). In energy storage systems comprising at least two battery devices, the BMS can connect to at least two BMUs to control and monitor the status of both battery devices.

[0114] The energy storage system can specifically be an energy storage box (also known as a large energy storage device, suitable for large-scale industrial production or power distribution and other technical fields). The energy storage box includes an energy storage box body, which has a housing space. The inverter, battery management system and battery device are all located inside the energy storage box body.

[0115] The energy storage system can specifically be an energy storage cabinet (also known as an industrial and commercial energy storage device, suitable for small industrial and commercial power needs). The energy storage cabinet includes an energy storage cabinet body, which has a housing space. The inverter, battery management system and battery device are all located in the energy storage cabinet body.

[0116] Thirdly, this application provides some embodiments of electrical equipment, which may also be referred to as an electrical system. Electrical equipment may include the battery device described above, and may be devices that utilize electrical energy, such as trams, power grids, or household appliances.

[0117] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery device, characterized in that, The battery device includes: The housing has a receiving cavity inside, which is used to hold the immersion liquid; At least two battery cells are disposed at intervals along a first direction within the receiving cavity, with a gap space between adjacent battery cells. An integrated busbar is disposed within the receiving cavity and located above the battery cell. The integrated busbar includes a support plate, which has a liquid passage hole extending vertically. The liquid passage hole is located above the spacer space and communicates with the spacer space. A separator is provided in the same spaced interval, at least two spaced separators are provided, a first flow channel is provided between the two spaced separators, the extension direction of the first flow channel is parallel to the vertical direction, and the first flow channel is connected to the liquid passage hole. The first flow channel includes a converging section and an expanding section connected to each other. The converging section is located below the expanding section. The area of ​​the cross-section of the converging section perpendicular to the vertical direction decreases from bottom to top, and the area of ​​the cross-section of the expanding section perpendicular to the vertical direction increases from bottom to top. A second flow channel is provided on the partition located on at least one side of the first flow channel. The overall height of the second flow channel is lower than the overall height of the expanding section. The first end of the second flow channel is connected to the connection between the converging section and the expanding section, and the second end of the second flow channel is connected to the outside of the partition space.

2. The battery device according to claim 1, characterized in that, The liquid passage has a dimension W1 along the first direction, and the space has a dimension G1 along the first direction. The ratio of the dimension W1 to the dimension G1 is in the range of 0.5 to 2.

3. The battery device according to claim 1, characterized in that, The fluid passage has a dimension L1 along the second direction, and the spacer has a dimension D1 along the second direction. Each pair of the first direction, the second direction, and the up-down direction is perpendicular to each other, and the ratio of the dimension L1 to the dimension D1 is in the range of 0.6 to 0.

8.

4. The battery device according to claim 1, characterized in that, The extension direction of the second flow channel is perpendicular to the extension direction of the contraction section, or the angle between the extension direction of the second flow channel and the extension direction of the contraction section is an acute angle.

5. The battery device according to claim 1, characterized in that, The housing is provided with a cavity inlet, which is connected to the receiving cavity. The inlet of the contraction section away from the expansion section is located above the cavity inlet.

6. The battery device according to claim 1, characterized in that, The separator is integrally formed with the tray or can be detachably connected.

7. The battery device according to any one of claims 1 to 3, characterized in that, The battery device also includes a flow guide tube located above the liquid passage hole. The flow guide tube has a cavity extending in the vertical direction, and the bottom of the cavity is connected to the liquid passage hole.

8. The battery device according to claim 7, characterized in that, The area of ​​the cross section of the cavity perpendicular to the vertical direction gradually decreases from bottom to top.

9. The battery device according to claim 7, characterized in that, The guide tube is integrally formed with the tray or can be detachably connected.

10. The battery device according to any one of claims 1 to 3, characterized in that, The tray includes a main body and at least two spaced-apart support portions. The support portions extend downward from the lower surface of the main body to the top wall of the battery cell. A third flow channel is provided between the two spaced-apart support portions. The third flow channel extends along the first direction and is connected to the liquid passage and the spacer.

11. The battery device according to any one of claims 1 to 3, characterized in that, The lower surface of the tray is recessed and a fourth flow channel is provided. The fourth flow channel extends along the first direction and is connected to the liquid passage and the spacer.

12. An energy storage system, characterized in that, The energy storage system includes the battery device according to any one of claims 1 to 11.

13. An electrical appliance, characterized in that, The electrical equipment includes the battery device according to any one of claims 1 to 11.

Images