Battery cell inversion type energy storage box integrating cooling and fire fighting and energy storage cabinet group

Abstract

The utility model relates to a cooling and fire-fighting integrated battery cell inversion type energy storage box and energy storage cabinet group, the energy storage box comprises a box body and at least one battery group, the battery group comprises battery cells arranged in an inverted mode, the tops of the battery cells face the bottom of the box body, a first liquid accumulation cavity is formed in the bottom of the box body, and a second liquid accumulation cavity is formed in the bottom of the box body. An explosion valve and a tab of the battery cell are positioned below the surface liquid level height of the first liquid accumulation cavity; a containing gap is formed between every two adjacent battery cells, a heat dissipation flow channel is formed in each containing gap and comprises a flow channel inlet, a flow channel outlet and at least one liquid accumulation flow channel, and the side surfaces of the battery cells are directly cooled through refrigerants of the liquid accumulation flow channels; and effective heat exchange is carried out on the explosion valve and the tab at the top of the battery cell through the first liquid accumulation cavity, so that the whole heat dissipation of the battery cell can be realized only by storing a small amount of refrigerant at the bottom of the box body, the heat exchange efficiency of immersion liquid is improved, the liquid consumption is greatly reduced, and the manufacturing cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of battery energy storage technology, and in particular to an inverted battery cell energy storage box and energy storage cabinet group with integrated cooling and fire protection. Background Art

[0002] With the rapid development of demand for new energy storage, energy storage safety has become a crucial part of energy storage projects. In particular, thermal management technology is a top priority for energy storage safety control. Currently, energy storage thermal management mostly adopts two methods: air cooling and liquid cooling. As the charge and discharge rates of energy storage products gradually increase, air cooling solutions can no longer meet the heat dissipation needs of battery cells. Immersion liquid cooling has become a key research direction for battery thermal management needs in the energy storage industry. It is also called direct liquid cooling. Immersion liquid cooling refers to directly immersing the battery cells in an insulating, non-toxic, heat-dissipating cold medium, and removing heat through the liquid to achieve a higher level of thermal management. It has the advantages of rapid cooling and good temperature uniformity. In addition to being a temperature control medium, the cold medium can also be used as a fire-fighting fluid for energy storage systems, combining temperature control and fire protection to achieve long-term safe operation of energy storage systems.

[0003] Currently, there are two main types of immersion liquid cooling: tank-level immersion and pack-level immersion. Tank-level immersion requires high sealing design, is prone to leakage, and requires a large amount of liquid, resulting in a very high system cost. Furthermore, later maintenance of battery cell failures requires draining the entire tank and then opening it for repair, which is demanding and complex. Pack-level immersion offers relatively easy maintenance and reduces the difficulty of sealing design, but it is prone to localized hot spots, and the pack needs to withstand pressure, resulting in high manufacturing costs and still requiring a large amount of liquid. Utility Model Content

[0004] To overcome the above-mentioned deficiencies of the prior art, the present application provides an inverted cell energy storage box and energy storage cabinet group with integrated cooling and fire protection, which specifically adopts the following technical solutions:

[0005] An inverted cell energy storage box with integrated cooling and fire protection, characterized in that it comprises a box body and a battery group arranged inside the box body,

[0006] The battery assembly includes an inverted battery cell, a bursting valve and a tab are provided on the top of the battery cell, the top of the battery cell faces the bottom of the box, and a flow guide gap is provided between the top of the battery cell and the bottom of the box, the bottom of the box is provided with a first liquid accumulation cavity connected to the flow guide gap, and the bursting valve and the tab of the battery cell are located below the surface liquid level of the first liquid accumulation cavity;

[0007] An accommodating gap is provided between adjacent battery cells, and a heat dissipation channel is provided in the accommodating gap. The heat dissipation channel includes a channel inlet, a channel outlet and at least one liquid accumulation channel. The channel inlet is located at the edge of the bottom of the battery cell, and the channel outlet is located at the side edge or top of the battery cell. The liquid accumulation channel is close to the side surface of the battery cell, and at least one liquid accumulation channel is connected between the channel inlet and the channel outlet. The refrigerant flows into the liquid accumulation channel through the channel inlet, and the refrigerant overflowing from the liquid accumulation channel flows out from the channel outlet, wherein the refrigerant in the liquid accumulation channel directly cools the side surface of the battery cell.

[0008] Optionally: a diversion liquid inlet device is provided at the top of the box body corresponding to the battery grouping position, and the diversion liquid inlet device is provided with a plurality of refrigerant outlets for distributing the refrigerant above the battery cells.

[0009] Optionally, a first liquid inlet is provided on the top of the box body, one end of the first liquid inlet is connected to an external liquid inlet pipeline, and the other end of the first liquid inlet extends into the box body and is connected to the diversion liquid inlet device.

[0010] Optionally, a liquid outlet connected to an external liquid return pipeline is provided at the bottom of the box body, and the lower edge height of the liquid outlet is higher than or equal to the liquid level height of the first liquid accumulation cavity.

[0011] Optionally: a first partition is further provided in the accommodating gap, and the heat dissipation channel is located between the first partition and the side surface of the battery cell.

[0012] Optionally: the heat dissipation channel adopts a first guide bar and a second guide bar arranged alternately at intervals, wherein the ends of the first guide bars close to the bottom of the battery cell are connected to each other, and the ends of the second guide bars close to the top of the battery cell are connected to each other, and the other ends of the first guide bar and the second guide bar are staggered, and the heat dissipation channel is formed by enclosing the first guide bar and the second guide bar.

[0013] Optionally: a second liquid inlet is provided on the top of the box body, one end of the second liquid inlet is connected to an external liquid inlet pipeline, and the other end of the second liquid inlet extends into the box body and is connected to a fire-fighting liquid inlet device.

[0014] Optionally, both ends of the battery pack further include end plates, and the heat dissipation channel is located between the end plates and the battery cells.

[0015] Optionally: the coverage area of ​​the liquid accumulation channel is 50% or more of the side surface area of ​​the battery cell.

[0016] Optionally: a plurality of staggered first capillary channels and second capillary channels are provided on the top of the battery cell, wherein the first capillary channels are parallel to the length direction of the battery cell, the second capillary channels are parallel to the width direction of the battery cell, and the width of the first capillary channels is greater than the width of the second capillary channels.

[0017] Optionally, the first guide bar and the second guide bar are integrally connected to the side surfaces of the battery cell.

[0018] Optionally, the first guide bar and the second guide bar are respectively integrally connected to the side surface of the first partition.

[0019] Optional: The heat dissipation channel is provided with two liquid accumulation channels, the channel inlet is located in the middle of the bottom of the battery cell, and a channel outlet is provided on both sides of the top of the battery cell. Each channel outlet is connected to a liquid accumulation channel, and the refrigerant enters the two liquid accumulation channels respectively through the channel inlet, and the refrigerant overflowing from the liquid accumulation channel flows out through the channel outlet connected to each liquid accumulation channel.

[0020] Optional: The heat dissipation channel is provided with two liquid accumulation channels, the channel inlet is located in the middle of the bottom of the battery cell, and a channel outlet is provided on each side edge of the battery cell near the bottom of the battery cell. Each channel outlet is connected to a liquid accumulation channel, and the refrigerant enters the two liquid accumulation channels respectively through the channel inlet, and the refrigerant overflowing from the liquid accumulation channel flows out through the channel outlet connected to each liquid accumulation channel.

[0021] The heat dissipation channel is provided with two liquid accumulation channels, the channel inlet is located in the middle position of the top of the battery cell, and a channel outlet is provided on one side edge of the battery cell near the bottom of the battery cell. The upper openings of the two liquid accumulation channels remain connected, and the refrigerant enters the two liquid accumulation channels in turn through the channel inlet, and the refrigerant overflowing from the liquid accumulation channel flows out through the channel outlet on the side edge of the battery cell.

[0022] A liquid level gauge for monitoring the refrigerant liquid level is provided inside the box, and a second solenoid valve is provided at the liquid outlet, and the opening and closing states of the second solenoid valve are controlled by a monitoring signal from the liquid level gauge.

[0023] In addition, the present application also discloses an energy storage cabinet group, which includes the above-mentioned inverted battery cell energy storage box, a liquid inlet pipeline, a liquid return pipeline, a liquid storage and cooling assembly, and an energy storage cabinet body. The inverted battery cell energy storage box, the liquid inlet pipeline, the liquid return pipeline, and the liquid storage and cooling assembly are all installed in the energy storage cabinet body, wherein multiple inverted battery cell energy storage boxes are stacked, and the inverted battery cell energy storage boxes and the liquid storage and cooling assembly are connected through the liquid inlet pipeline and the liquid return pipeline to form a cooling circulation loop.

[0024] Beneficial effects

[0025] The technical solution of this application has the following beneficial effects:

[0026] (1) The energy storage box of the present application inverts the battery cell so that the burst valve or the tab of the battery cell is always immersed in the refrigerant, and the adjacent battery cells are thermally isolated by the liquid accumulation flow channel that continuously stores liquid in the heat dissipation flow channel. When the temperature of the battery cell rises, the refrigerant in the liquid accumulation flow channel partially evaporates and absorbs heat, thereby avoiding excessive temperature increase, effectively suppressing the heat spread after thermal runaway of the battery cell, and ensuring safe and reliable operation of the battery cell.

[0027] (2) When the energy storage box of the present application is in thermal runaway, the heat inside the battery cell can be absorbed by the refrigerant stored in the liquid accumulation channel, and the liquid absorbs heat and heats up to its boiling point to vaporize, thereby preventing the spread of heat and causing thermal runaway of adjacent battery cells. In addition, after the top pressure relief valve explodes due to thermal runaway of the battery cell, the ejected high-temperature gas enters the battery after being cooled by the liquid in the first liquid accumulation chamber. The cooled gas is difficult to react with oxygen, effectively avoiding secondary combustion runaway. At the same time, after the pressure relief valve on the top of the thermally runaway battery cell is depressurized, the pressure relief valve is immersed in the water seal of the insulating cold fluid in the first liquid accumulation chamber at the bottom of the box body, thereby preventing the oxygen in the box body from entering the battery cell for chemical reaction, thereby further suppressing the spread of thermal runaway of the battery cell.

[0028] (3) The energy storage box of the present application adopts a semi-immersed battery pack design. It evenly distributes liquid on the top of the box body and combines the heat dissipation flow channel to evenly cover the bottom and sides of the battery cell with refrigerant for overflow heat exchange. The bottom of the box body only needs to store a small amount of refrigerant that does not cover the top of the battery cell to achieve overall heat dissipation of the battery cell. It not only improves the heat exchange efficiency of the immersion liquid and avoids local hot spots in the battery cell, thereby avoiding affecting the normal operation of the system; it also greatly reduces the amount of liquid used. On the premise of maintaining the ultimate heat dissipation performance of the immersion cooling method, it greatly reduces the cost of the entire system.

[0029] (4) The energy storage box of the present application can effectively control the overall operating weight of the device by significantly reducing the amount of liquid used, thereby reducing deployment and installation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the installation structure in which the battery group is located inside the box in an embodiment of the present application.

[0031] Figure 2 This is a schematic diagram of the overall structure of the energy storage box in an embodiment of the present application.

[0032] Figure 3 This is a schematic structural diagram of the energy storage box in an embodiment of the present application after removing the upper cover of the box body.

[0033] Figure 4 This is a schematic diagram of the internal structure of the energy storage box in the embodiment of the present application.

[0034] Figure 5 This is a schematic diagram of the lateral internal structure of the energy storage box in an embodiment of the present application.

[0035] Figure 6 This is a schematic diagram of the bottom structure of the energy storage box in an embodiment of the present application.

[0036] Figure 7 This is a schematic diagram of the assembly structure of the battery pack in the embodiment of the present application.

[0037] Figure 8 Schematic diagram of the structure of the heat dissipation channel in the embodiment of the present application.

[0038] Figure 9 This is a schematic diagram of a heat dissipation channel structure located on the first partition in an embodiment of the present application.

[0039] Figure 10 This is a schematic diagram of another heat dissipation channel structure located on the first partition in an embodiment of the present application.

[0040] Figure 11 This is a schematic diagram of another heat dissipation channel structure located on the first partition in an embodiment of the present application.

[0041] Figure 12 Schematic diagram of the structure of the energy storage cabinet group in the embodiment of the present application.

[0042] The specific meanings of the reference numerals in the accompanying drawings are:

[0043] 1-box; 101-top of the box; 102-bottom of the box; 103-first liquid inlet; 104-second liquid inlet; 105-liquid outlet; 106-first liquid accumulation chamber; 107-guide channel; 2-battery cell; 201-top of the battery cell; 202-bottom of the battery cell; 203-edge of the bottom of the battery cell; 204-burst valve; 205-ear; 3-first partition plate; 31-heat dissipation channel; 301-channel inlet; 302-liquid accumulation channel; 303-channel outlet; 304-first guide strip; 305-second guide strip; 4-diversion liquid inlet device; 401-liquid inlet manifold; 402-diversion branch pipe; 5-guide gap; 6-end plate; 7-accommodation gap.

[0044] 1-1, energy storage box; 1-2, liquid inlet pipeline; 1-3, liquid return pipeline; 1-4, liquid storage cooling assembly; 1-5, drain valve; 1-6, pressure relief valve; 1-7, energy storage cabinet. DETAILED DESCRIPTION

[0045] The present application will be further described below in conjunction with the accompanying drawings. The following examples are only used to more clearly illustrate the technical solutions of the present application and are not intended to limit the scope of protection of the present application. It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application.

[0046] Currently, energy storage tanks are generally cooled by immersion liquid cooling, which mainly includes two types: TANK full immersion and PACK full immersion. The TANK full immersion method fills the tank with refrigerant, places the battery cells in the container, and then immerses the tank inside, so that the refrigerant completely immerses the cell container. This method requires high sealing structure design, is prone to leakage problems, and requires a large amount of liquid, making the system costly. In addition, when repairing battery cell failures later, the entire tank needs to be drained and repaired, which requires high maintenance requirements and is complicated. The PACK full immersion method, on the other hand, places the battery cells directly in the tank. Although maintenance is relatively convenient and the sealing design is less difficult, it is prone to local hot spots, and the battery pack needs to withstand pressure, which is costly to manufacture and still requires a large amount of liquid.

[0047] It should be noted that in this application, the top 201 of the battery cell generally refers to the surface of the battery cell 2 where the burst valve 204 is located, and the bottom 202 of the battery cell generally refers to the surface of the battery cell 2 opposite the burst valve 204. In this application, the battery cell is placed upside down, which means that the battery cell 2 is located inside the energy storage box body 1, with the side of the battery cell 2 containing the burst valve 204 (generally the top 201 of the battery cell) facing the bottom 102 of the box body, and the side of the battery cell 2 opposite the burst valve 204 (generally the bottom 202 of the battery cell) facing the top 101 of the box body.

[0048] Combine Figure 1-6 As shown, an embodiment of the present application specifically discloses an energy storage box with integrated cooling and fire protection, which includes a box body 1 and at least one battery group, wherein each of the battery groups includes a number of battery cells 2 distributed side by side and placed inverted, and the positive and negative pole ears 205 of each battery cell are connected in series in sequence, wherein in the present application, a diverter liquid inlet device 4 is provided at the position of the battery group corresponding to the top 101 of the box body, and the diverter liquid inlet device 4 is provided with a refrigerant outlet, and the refrigerant is distributed above the battery cell 2 through the refrigerant outlet of the diverter liquid inlet device 4, and the refrigerant from the top 101 of the box body can be evenly distributed to the surface of the bottom 201 of the battery cell for heat dissipation, and then the refrigerant flows downward from the side of the battery cell 2 due to gravitational potential energy, thereby cooling the side surface of the battery cell 2, and finally gathering at the bottom 102 of the box body. At the same time, the top 101 of the box body is provided with a first liquid inlet 103, one end of the first liquid inlet 103 is connected to the external liquid inlet pipeline, and the other end of the first liquid inlet 103 extends into the box body 1 and is connected to the diverter liquid inlet device 4. The refrigerant in the external liquid inlet pipeline enters the box body 1 of the energy storage box through the first liquid inlet 103 and is evenly distributed to the top of the battery group by the diverter liquid inlet device 4. It should be noted that, in combination with Figure 1 and Figure 3As shown, the diversion liquid inlet device 4 described in the present application includes a liquid inlet manifold 401 and at least one diversion branch 402, wherein the liquid inlet manifold 401 mainly distributes the refrigerant from the outside evenly to the multiple diversion branches 402. Preferably, in the present application, a diversion branch 402 is provided at the position above each battery group corresponding to the top 101 of the box body, and the diversion branch 402 is provided with a refrigerant outlet corresponding to the position of each battery cell 2; multiple diversion branches 402 are connected to the same liquid inlet manifold 401, and the liquid inlet manifold 401 is connected to the liquid inlet pipeline outside the box body 1 through the first liquid inlet 103. The external refrigerant flows from the liquid inlet pipeline and the first liquid inlet 103 to the liquid inlet manifold 401 inside the box body 1, and the refrigerant is distributed to the multiple diversion branches 402 through the multiple outlets of the liquid inlet manifold 401. The multiple refrigerant outlets of the diversion branch 402 are evenly distributed on the bottom surface of each battery cell 2. It should be noted that there is no limit on the number of branch pipes 402 in the present application. One branch pipe 402 or multiple branch pipes 402 can be set on each battery group; or two battery groups can share one branch pipe 402. The number and distribution position of the branch pipes 402 in the present application can be adjusted based on the internal structure of the energy storage box and the refrigerant flow requirements.

[0049] Furthermore, in order to avoid heat transfer between adjacent cells 2 and due to the need for self-cooling, the present application provides heat dissipation channels 31 on both sides of the cell 2. Figure 7 and Figure 8 As shown, the heat dissipation channel 31 includes a channel inlet 301, a channel outlet 303 and at least one liquid accumulation channel 302, the channel inlet 301 is located at the edge 203 of the bottom 202 of the battery cell, the channel outlet 303 is located at the side or top 201 of the battery cell 2, the liquid accumulation channel 302 is close to the side surface of the battery cell 2, and at least one of the liquid accumulation channel 302 is connected between the channel inlet 301 and the channel outlet 303, the refrigerant flows into the liquid accumulation channel 302 through the channel inlet 301, and the refrigerant overflowing from the liquid accumulation channel 302 flows out from the channel outlet 303, wherein the refrigerant located in the liquid accumulation channel 302 directly cools the side surface of the battery cell 2. It should be understood that since the battery group includes multiple battery cells 2, an accommodating gap 7 is provided between adjacent battery cells 2, as shown in FIG. Figure 7 As shown, the heat dissipation channel 31 is located in the accommodating gap 7. It should be noted that in the present application, the heat dissipation channel 31 can be directly formed by the accommodating gap 7, or can be formed by the bonding surface of the first partition 3 and the battery cell 2.

[0050] It should be noted that the refrigerant in the heat dissipation channel 31 of the present application directly dissipates heat on the side surface of the battery cell 2, which greatly improves the heat dissipation efficiency compared to the traditional liquid cooling plate method. In addition, the liquid accumulation channel 302 of the present application can accumulate some refrigerant. When the energy storage box is working normally, the refrigerant circulates from top to bottom inside the box body 1, which can achieve heat dissipation for the bottom 202 and side of the battery cell and isolate the heat transfer between adjacent battery cells 2. When the energy storage box stops working (generally, the refrigerant no longer circulates), at this time, since some refrigerant is accumulated in the liquid accumulation channel 302, the refrigerant located in the liquid accumulation channel 302 can isolate the heat transfer between adjacent battery cells 2. Therefore, the energy storage box in the present application not only achieves heat dissipation and cooling during the normal working stage, but also can achieve heat insulation for the battery cells 2 of the energy storage box after it stops working, thereby ensuring that the thermal runaway of the battery cell 2 spreads to the adjacent battery cell 2, thereby improving the safety of the energy storage box.

[0051] It should be noted that, when the energy storage box is working normally, the heat of the burst valve 204 and the tab 205 at the top 201 of the battery cell is relatively concentrated, so in order to cool the top 201 of the battery cell and achieve the overall heat dissipation effect of the battery cell 2. Figure 1 and Figure 8 As shown, in this application, the battery cell 2 is placed upside down inside the box, with the top 201 of the battery cell facing the bottom 102 of the box, and a guide gap 5 is provided between the top 201 of the battery cell and the bottom 102 of the box. The bottom 102 of the box is provided with a first liquid accumulation cavity 106 connected to the guide gap 5, and the burst valve 204 and the tab 205 of the battery cell 2 are located below the surface liquid level 1061 of the first liquid accumulation cavity 106. Figure 1 As shown, the top 201 of the cell is partially immersed in the first liquid accumulation chamber 106. It should be understood that in the present application, the bottom 202 and side surfaces of the cell are cooled by the refrigerant in the top 101 of the box body and the refrigerant in the side heat dissipation channel 31 respectively, while the top 202 of the cell can be cooled by immersion in the refrigerant in the first liquid accumulation chamber 106 of the bottom 102 of the box body. After the refrigerant flowing from the top 11 of the box body to the battery array is separated to the surface of the bottom 202 of the cell, it flows along the side surface of the cell 2 toward the top 201 of the cell due to gravitational potential energy, and is collected at the bottom 102 of the box body, and finally accumulates in the first liquid accumulation chamber 106, and is then discharged from the first liquid accumulation chamber 106 to the outside of the box body 1, and the refrigerant is cooled by the external liquid storage and cooling assembly and re-delivered to the liquid inlet pipeline.

[0052] It should be understood that in the present application, by immersing the top 201 of the battery cell in the first liquid accumulation chamber 106, the bursting valve 204 or the tab 205 can be sealed by the refrigerant to prevent the bursting valve 204 or the tab 205 from contacting the oxygen in the box body 1, thereby improving the life of the tab 205 and at the same time, the bursting valve 204 can be sealed when the battery cell 2 thermally runs away, thereby preventing the inside of the battery cell 2 from contacting with external oxygen and preventing the thermal runaway from worsening.

[0053] It should be noted that in this application, in order to ensure uniform heat dissipation at all locations on the surface of the battery cell bottom 202, a number of staggered first capillary channels and second capillary channels can be provided on the battery cell bottom 202, wherein the first capillary channel is parallel to the length direction of the battery cell 2, the second capillary channel is parallel to the width direction of the battery cell 2, and the width of the first capillary channel is greater than the width of the second capillary channel. Since the width of the first capillary channel is greater than the width of the second capillary channel, the flow rate of the refrigerant in the first capillary channel is faster than the flow rate of the refrigerant in the second capillary channel. When the refrigerant covers the surface of the battery cell bottom 202, more refrigerant flows in the length direction of the battery cell 2, thereby making the heat dissipation rate of the battery cell bottom 202 consistent in the opposite direction of length and width, thereby improving the heat dissipation effect.

[0054] It should be explained that in this application, the side surfaces of the cells at both ends of the battery pack are also provided with heat dissipation channels 31. Figure 5 and Figure 7 As shown, end plates 6 are provided at both ends of the battery assembly, and a receiving gap 7 is provided between the end plates 6 and the battery cells 2. The heat dissipation channel 31 is located in the receiving gap 7. Similarly, a first partition plate 3 can also be provided in the receiving gap 7 between the end plates 6 and the battery cells 2, and the heat dissipation channel 31 is located between the first partition plate 6 and the side surface of the battery cells 2.

[0055] It should be noted that this application is to ensure the stable flow of the refrigerant to the bottom 102 of the box body, reduce the lateral flow of the refrigerant (i.e., avoid the refrigerant flowing along the width direction of the battery group), so that the refrigerant at one end of the box body 1 can quickly flow back to the other end of the box body 1, and reduce the turbulent dead zone. Figure 6 As shown, a plurality of guide channels 107 are provided at the bottom 102 of the box body, and one end of the guide channels 107 is interconnected. Preferably, at least one guide channel 107 may be provided below each battery group, and the battery group may be placed on the bosses on both sides of the guide channel 107. Figure 1As shown, the bottom of the box body 1 is provided with a liquid outlet 105 connected to the external liquid return pipeline. The box body 1 in this application can be provided with at least one liquid outlet 105, and the liquid outlet 105 is arranged on a side of the box body 1 near the bottom, and the lower edge height of the liquid outlet 105 is higher than or equal to the maximum liquid level height of the first liquid accumulation chamber 106. It should be noted that when the refrigerant on the battery array flows to the guide channel 107 at the bottom 102 of the box body due to gravitational potential energy, and because one end of the guide channel 107 is interconnected to form a connecting part, the refrigerant at the bottom 102 of the box body can be concentrated from one end to the connecting part through the guide channel 107. This connecting part is close to the liquid outlet 105, so the refrigerant flows out of the box body 1 through the liquid outlet 105, and the refrigerant liquid level height at the bottom 102 of the box body is kept to immerse the top of the battery cell in the battery array. Therefore, the energy storage box of the present application does not require a large amount of refrigerant liquid. The bottom 102 of the box body only needs to store a small amount of refrigerant to achieve overall heat dissipation of the battery cell 2. It not only improves the heat exchange efficiency of the immersion liquid, but also greatly reduces the liquid consumption. While maintaining the ultimate heat dissipation performance of the immersion cooling method, the cost of the entire system is greatly reduced.

[0056] Further, such as Figure 2 As shown, the present application also provides a second liquid inlet 104 at the top 101 of the housing, wherein one end of the second liquid inlet 104 is connected to an external liquid inlet pipeline, and the other end of the second liquid inlet 104 extends into the housing 1 and is connected to a fire-fighting liquid inlet device. A first solenoid valve is provided between the second liquid inlet 104 and the liquid inlet pipeline, and the opening and closing states of the first solenoid valve control the flow of refrigerant to the fire-fighting liquid inlet device. It should be understood that in the present application, the refrigerant is generally evenly covered on the bottom 202 and sides of the battery cell by the diversion liquid inlet device 4 and the heat dissipation flow channel 31, thereby achieving overflow heat exchange, achieving overall heat dissipation of the battery cell 2, and also serving a fire-fighting function. Once thermal runaway intensifies and the internal temperature of the energy storage box increases sharply, the energy storage box of the present application will open the first solenoid valve. At this time, a large amount of refrigerant will enter the interior of the housing 1 through the fire-fighting liquid inlet device, causing the interior of the housing 1 to change from a semi-immersed state to a fully immersed state, thereby providing fire-fighting control for the runaway battery cell 2 and further improving the safety of the energy storage box.

[0057] Furthermore, the present application may also provide a second solenoid valve at the liquid outlet 105, and a liquid level gauge for monitoring the liquid level of the refrigerant in the first liquid accumulation chamber 106 is provided inside the housing 1, and the opening and closing state of the second solenoid valve is controlled by the monitoring signal of the liquid level gauge. It should be understood that since the top 201 of the battery cell needs to be immersed in the refrigerant in the first liquid accumulation chamber 106 to ensure heat dissipation, and to avoid excessive accumulation of refrigerant inside the housing 1, the liquid level of the first liquid accumulation chamber 106 can be monitored by a liquid level gauge, and a liquid level threshold can be set. Once the actual liquid level of the first liquid accumulation chamber 106 exceeds the set liquid level threshold, the opening of the second solenoid valve is increased, the flow rate of the liquid outlet 105 is increased, and the liquid level of the first liquid accumulation chamber 106 is reduced to below the liquid level threshold, thereby ensuring that only a small amount of refrigerant is accumulated in the housing 1, significantly reducing the amount of liquid used, effectively controlling the overall operating weight of the device, and reducing deployment and installation requirements.

[0058] More specifically, the heat dissipation channel in this application can be formed by the first guide bar 304 and the second guide bar 305 provided between adjacent battery cells 2, combined with Figure 8 As shown, the first guide bar 304 and the second guide bar 305 of the present application are arranged alternately at intervals, wherein the end of the first guide bar 304 close to the bottom 202 of the battery cell is connected to each other, and the end of the second guide bar 305 close to the top 201 of the battery cell is also connected to each other; and the other ends of the first guide bar 304 and the second guide bar 305 are not flush, and are arranged alternately. When two battery cells 2 are assembled, the first guide bar 304 and the second guide bar 305 will be close to the side surfaces of the two battery cells 2, and the side surfaces of the battery cells 2, the first guide bar 304 and the second guide bar 305 will enclose a heat dissipation channel 31 located between adjacent battery cells 2. It should be understood that the heat dissipation channel 31 formed by this structure directly uses the side surface of the battery cell 2 as the inner wall, so that the refrigerant flowing through the heat dissipation channel 31 directly dissipates heat and cools the side surface of the battery cell 2, thereby improving the heat dissipation efficiency. Furthermore, as a connection structure of this heat dissipation channel, the first guide bar 304, the second guide bar 305 and the side surface of the battery cell 2 in the present application can be connected in an integrated molding manner, for example, an injection molding structure of the guide bar is opened on the injection mold of the battery cell 2 shell, so that the guide bar is directly formed on the side surface during the injection molding of the battery cell 2 shell, or the first guide bar 304 and the second guide bar 305 are manufactured separately, and during assembly, the first guide bar 304 and the second guide bar 305 are fixed to the side surface of the battery cell 2 by bonding, welding or snapping.

[0059] As another embodiment of the heat dissipation channel, the present application can also set a first partition 3 between adjacent battery cells 2. Generally, the first partition 3 can be made of heat-insulating and insulating materials, and then a first guide bar 304 and a second guide bar 305 are provided on both sides of the first partition 3. Figure 9-11As shown, the first guide bar 304 and the second guide bar 305 of the present application are arranged alternately and at intervals, and the ends of the first guide bar 304 and the second guide bar 305 are not flush and are staggered, wherein the end of the first guide bar 304 close to the bottom 202 of the battery cell (corresponding to the top of the first partition) is connected to each other, and the end of the second guide bar 305 close to the top 201 of the battery cell (corresponding to the bottom of the first partition) is also connected to each other. When two battery cells 2 are assembled, the first partition 3 is clamped between adjacent battery cells 2. At this time, the first guide bar 304 and the second guide bar 305 will be close to the side surfaces of the battery cell 2 and the first partition 3 respectively, and the heat dissipation channel 31 located between adjacent battery cells 2 is formed by the side surface of the battery cell 2, the side surface of the first partition 3, the first guide bar 304 and the second guide bar 305. It should be noted that the heat dissipation channel 31 formed by this structure directly uses the side surface of one of the battery cells 2 as the inner wall, so that the refrigerant flowing through the heat dissipation channel 31 directly dissipates heat and cools the side surface of the battery cell 2, thereby improving the heat dissipation efficiency. In addition, as a connection structure of this heat dissipation channel, the first guide bar 304 and the second guide bar 305 in the present application can be respectively connected to the side surface of the first partition 3 in an integral molding. For example, an injection molding structure of the guide bar is provided on the injection mold of the first partition 3, so that the guide bars are directly formed on the two side surfaces of the first partition 3 during injection molding. Alternatively, the first guide bar 304 and the second guide bar 305 are manufactured separately, and during assembly, the first guide bar 304 and the second guide bar 305 are fixed to the side surface of the first partition 3 by bonding, welding or snapping.

[0060] It should be noted that the coverage area of ​​the liquid accumulation channel 302 in this application is generally 50% or more of the side surface area of ​​the battery cell 2. The liquid accumulation channel 302 is used to accumulate part of the refrigerant. The refrigerant accumulated in the liquid accumulation channel 302 is mainly used to dissipate heat from the side of the battery cell 2 and prevent the heat from spreading to the adjacent battery cells 2. On the one hand, the accumulated refrigerant can be used to dissipate heat from the battery cell 2. In order to improve the effect, the larger the coverage area of ​​the liquid accumulation channel 302, the better. On the other hand, when the energy box is not in operation, even if the battery cell 2 has thermal runaway, the heat generated inside the battery cell 2 will preferentially heat the refrigerant in the liquid accumulation channel 302. The liquid absorbs heat and heats up to its boiling point and vaporizes, thereby preventing the heat from spreading and causing thermal runaway of the adjacent battery cells 2.

[0061] As a specific implementation of the heat dissipation channel structure, Figure 9Taking the structure shown as an example, the heat dissipation channel is located between the battery cell and the first partition. The heat dissipation channel 31 in this embodiment is provided with two liquid accumulation channels 302, the channel inlet 301 is located in the middle of the bottom 202 of the battery cell (corresponding to the top of the first partition), and a channel outlet 303 is provided on both sides of the top 201 of the battery cell (corresponding to the bottom of the first partition), each channel outlet 303 is connected to a liquid accumulation channel 302, and the refrigerant enters the two liquid accumulation channels 302 respectively through the channel inlet 301 due to gravitational potential energy. When the refrigerant in the two liquid accumulation channels 302 accumulates and overflows, the overflowed refrigerant flows to the bottom of the box body 1 through the channel outlets 303 on both sides of the battery cell 2. When the refrigerant stops flowing, refrigerant always remains in the two liquid accumulation channels 302, and the refrigerant can isolate the heat transfer between the battery cells 2 to prevent the thermal runaway of the battery cells 2 from spreading.

[0062] As another specific embodiment of the heat dissipation channel structure, Figure 10 Taking the structure shown as an example, the heat dissipation channel in this embodiment is provided with two liquid accumulation channels 302. The channel inlet 301 is located in the middle of the bottom 202 of the battery cell (corresponding to the top of the first partition), and a channel outlet 303 is provided on both sides of the battery cell (corresponding to the two sides of the first partition) near the bottom 202 of the battery cell. Each channel outlet 303 is connected to a liquid accumulation channel 302. The refrigerant enters the two liquid accumulation channels 302 through the channel inlet 301. The refrigerant overflowing from the liquid accumulation channel 302 flows out through the channel outlet 303 connected to each liquid accumulation channel 302. When the refrigerant stops flowing, refrigerant always remains in the two liquid accumulation channels 302. The refrigerant can isolate the heat transfer between the battery cells 2 to prevent the spread of thermal runaway of the battery cells 2.

[0063] As another specific embodiment of the heat dissipation channel structure, Figure 11 Taking the structure shown as an example, the heat dissipation channel in this embodiment is provided with two liquid accumulation channels 302, with the channel inlet 301 located in the middle of the bottom 202 of the battery cell (corresponding to the top of the first partition), and a channel outlet 303 is provided on one side of the battery cell (corresponding to one side of the first partition) near the bottom 202 of the battery cell. The upper openings of the two liquid accumulation channels 302 remain connected, and the refrigerant enters the two liquid accumulation channels 302 in sequence through the channel inlet 301. The refrigerant overflowing from the liquid accumulation channels 302 flows out through the channel outlet 303 on the side of the first partition 3. When the refrigerant stops flowing, refrigerant always remains in the two liquid accumulation channels 302, which can isolate the heat transfer between the battery cells 2 to prevent the spread of thermal runaway of the battery cells 2.

[0064] In addition, the present application also discloses an energy storage cabinet group, combined with Figure 12As shown, it includes the energy storage box 1-1, liquid inlet pipeline 1-2, liquid return pipeline 1-3, liquid storage cooling assembly 1-4 and energy storage cabinet 1-7 as described in the above embodiment. The energy storage box 1-1, liquid inlet pipeline 1-2, liquid return pipeline 1-3, and liquid storage cooling assembly 1-4 are all installed in the energy storage cabinet 1-7, wherein multiple energy storage boxes 1-1 are stacked and connected to the energy storage box 1-1 and liquid storage cooling assembly 1-4 through the liquid inlet pipeline 1-2 and the liquid return pipeline 1-3 to form a cooling circulation loop. The liquid storage cooling assembly 1-4 in this application generally includes a liquid storage tank, a refrigeration module, a circulation pump and an electric heater, wherein the refrigerant is stored in the liquid storage tank, and the cooling module cools the refrigerant in the liquid storage tank using a cooling medium. The liquid storage tank is provided with at least three liquid outlets, one of which is connected to the liquid inlet pipe after being connected to the circulation pump and the electric heater in sequence. The circulation pump is used to provide driving force for the flow of refrigerant, and the electric heater is used to control the refrigerant in the liquid inlet pipe to maintain a constant temperature. Another liquid outlet of the liquid storage tank is connected to the return liquid pipe, which is used to recycle the refrigerant in the return liquid pipe. The liquid storage tank is also provided with a liquid outlet for discharging the refrigerant. Generally, the drain valve 1-5 corresponding to this position is closed. When the refrigerant is replaced, the drain valve 1-5 can be opened to empty the liquid inside the liquid storage tank and re-introduce new refrigerant. In order to avoid excessive internal pressure in the liquid storage cabinet group, a pressure relief valve can also be set on the return liquid pipe 1-3. The internal pressure is reduced by the pressure relief valve to promote the smooth flow of refrigerant.

[0065] Furthermore, the refrigerant control process of the energy storage cabinet group mentioned above in this application includes:

[0066] The liquid storage cooling assembly drives the refrigerant through the liquid inlet pipe into the energy storage tank at a preset flow rate and evenly distributes it to the battery pack. The refrigerant dissipates heat from the battery pack and collects at the bottom of the energy storage tank. The refrigerant at the bottom of the energy storage tank flows back to the liquid storage cooling assembly through the return pipe.

[0067] Then, the liquid level data of the first liquid accumulation chamber in the energy storage tank is collected by a liquid level meter;

[0068] When the liquid level of the first liquid accumulation chamber is lower than the first liquid level threshold, the inlet flow rate of the refrigerant passing through the inlet pipeline into the energy storage tank is increased or the return flow rate of the refrigerant flowing through the return pipeline is reduced to ensure that the refrigerant in the first liquid accumulation chamber covers the burst valve 204;

[0069] When the liquid level of the first liquid accumulation chamber is higher than the second liquid level threshold, the return flow rate of the refrigerant flowing through the return liquid pipeline is increased, which can ensure that only a small amount of refrigerant is retained in the box body 1, thereby reducing liquid consumption.

[0070] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. An inverted battery cell energy storage box with integrated cooling and fire protection, characterized in that: It includes a box body and a battery group arranged inside the box body. The battery assembly includes an inverted battery cell, a bursting valve and a tab are provided on the top of the battery cell, the top of the battery cell faces the bottom of the box, and a flow guide gap is provided between the top of the battery cell and the bottom of the box, the bottom of the box is provided with a first liquid accumulation cavity connected to the flow guide gap, and the bursting valve and the tab of the battery cell are located below the surface liquid level of the first liquid accumulation cavity; An accommodating gap is provided between adjacent battery cells, and a heat dissipation channel is provided in the accommodating gap. The heat dissipation channel includes a channel inlet, a channel outlet and at least one liquid accumulation channel. The channel inlet is located at the edge of the bottom of the battery cell, and the channel outlet is located at the side edge or top of the battery cell. The liquid accumulation channel is close to the side surface of the battery cell, and at least one liquid accumulation channel is connected between the channel inlet and the channel outlet. The refrigerant flows into the liquid accumulation channel through the channel inlet, and the refrigerant overflowing from the liquid accumulation channel flows out from the channel outlet, wherein the refrigerant in the liquid accumulation channel directly cools the side surface of the battery cell.

2. The inverted battery cell energy storage box according to claim 1, characterized in that: A diversion liquid inlet device is provided at the top of the box body corresponding to the battery grouping position, and the diversion liquid inlet device is provided with a plurality of refrigerant outlets for distributing the refrigerant above the battery core.

3. The inverted battery cell energy storage box according to claim 2, characterized in that: A first liquid inlet is provided on the top of the box body, one end of the first liquid inlet is connected to an external liquid inlet pipeline, and the other end of the first liquid inlet extends into the box body and is connected to the diversion liquid inlet device.

4. The inverted battery cell energy storage box according to claim 1, characterized in that: A liquid outlet connected to an external liquid return pipeline is provided at the bottom of the box body, and the height of the lower edge of the liquid outlet is higher than or equal to the liquid level height of the first liquid accumulation cavity.

5. The inverted battery cell energy storage box according to claim 1, characterized in that: A first partition is further provided in the accommodating gap, and the heat dissipation channel is located between the first partition and the side surface of the battery cell.

6. The inverted battery cell energy storage box according to claim 1, characterized in that: The heat dissipation channel adopts a first guide bar and a second guide bar arranged alternately at intervals, wherein the ends of the first guide bars close to the bottom of the battery cell are connected to each other, and the ends of the second guide bars close to the top of the battery cell are connected to each other, and the other ends of the first guide bar and the second guide bar are staggered, and the heat dissipation channel is formed by enclosing the first guide bar and the second guide bar.

7. The inverted battery cell energy storage box according to claim 1, characterized in that: A second liquid inlet is provided on the top of the box body, one end of the second liquid inlet is connected to an external liquid inlet pipeline, and the other end of the second liquid inlet extends into the box body and is connected to a fire-fighting liquid inlet device.

8. The inverted battery cell energy storage box according to claim 1, characterized in that: Both ends of the battery assembly further include end plates, and the heat dissipation channel is located between the end plates and the battery cells.

9. The inverted battery cell energy storage box according to claim 1, characterized in that: The coverage area of ​​the liquid accumulation channel is 50% or more of the side surface area of ​​the battery cell.

10. An energy storage cabinet group, characterized in that: The inverted cell energy storage box comprises the inverted cell energy storage box, the liquid inlet pipeline, the liquid return pipeline, the liquid storage cooling assembly, and the energy storage cabinet according to any one of claims 1 to 9 above, wherein the inverted cell energy storage box, the liquid inlet pipeline, the liquid return pipeline, and the liquid storage cooling assembly are all installed in the energy storage cabinet, wherein a plurality of the inverted cell energy storage boxes are stacked, and the inverted cell energy storage boxes and the liquid storage cooling assembly are connected through the liquid inlet pipeline and the liquid return pipeline to form a cooling circulation loop.

Images