Energy storage battery box cover plate with heat absorption function

Abstract

The invention relates to the technical field of battery energy storage, in particular to an energy storage battery box cover plate with a heat absorption function, which comprises a cover plate, the cover plate comprises a cover plate main body and a collecting pipe; a phase-change material mounting cavity for storing a phase-change material is arranged in the cover plate main body, and one end of the cover plate main body is connected to the collecting pipe; an opening is formed in the position, corresponding to the phase-change material mounting cavity, of the collecting pipe; and when the heat absorption form of the phase change material is changed, the heat is discharged out of the phase change material mounting cavity through the collecting pipe. According to the invention, the heat in the battery box can be effectively absorbed, transferred and released without additional signal control or power supply by internally arranging the phase change material and utilizing the phase change process of the phase change material and the liquid flow of the phase change material, so that the thermal runaway risk is remarkably reduced, and the thermal runaway propagation speed in the battery cluster is delayed.

Description

Technical Field

[0001] The invention relates to the technical field of battery energy storage, and in particular to an energy storage battery box cover with a heat absorption function. Background Art

[0002] With the vigorous development of the energy storage industry, large-capacity energy storage systems have been put into use. At the same time, the single-cell capacity of energy storage batteries (such as lithium batteries) is also continuously increasing. However, once a single cell experiences thermal runaway, it will release a large amount of high-temperature gas and flames, causing the temperature of the top cover of the box to rise sharply, and may even cause burn-through. This situation not only directly threatens the battery pack located on the upper layer of the box where the thermal runaway battery is located, causing it to be continuously heated, but it may also cause the thermal runaway phenomenon to spread rapidly between battery packs because the heat cannot be effectively dissipated.

[0003] To address this problem, the industry generally adopts the method of selecting high-temperature resistant materials or adding high-temperature resistant coatings to enhance the high-temperature resistance of the box cover. Although these methods can slow down the spread of thermal runaway between battery packs to a certain extent, they do not fundamentally solve the problem of effectively controlling the release of energy from single cells. At the same time, the use of high-temperature resistant covers may cause heat to accumulate inside the battery pack, which in turn causes more batteries to experience thermal runaway in succession.

[0004] Therefore, how to quickly and effectively control the heat transfer within and between battery packs when thermal runaway occurs in a single cell, so as to slow down the spread of thermal runaway between battery packs, has become a technical problem that needs to be overcome urgently in the current energy storage field. Summary of the invention

[0005] The purpose of the present invention is to provide an energy storage battery box cover with heat absorption function in order to solve at least one of the above technical problems.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] An energy storage battery box cover with a heat absorption function comprises a cover, wherein the cover comprises: a cover body, a manifold;

[0008] A phase change material installation chamber for storing phase change material is provided inside the cover body, and one end of the cover body is connected to the manifold; an opening is provided at a position of the manifold corresponding to the phase change material installation chamber;

[0009] When the phase change material absorbs heat and changes in shape, the heat is discharged from the phase change material installation chamber through the manifold.

[0010] Furthermore, a directional pressure relief pipe is provided on the manifold; the directional pressure relief pipe is filled with paraffin for sealing.

[0011] Furthermore, the energy storage battery box cover plate further comprises: a flow guide assembly and a sealing terminal; the sealing terminal is made of a low melting point alloy;

[0012] The end of the cover plate body away from the manifold is connected to a shunt pipe, and a liquid flow channel is provided inside the cover plate body; the two ends of the liquid flow channel are respectively connected to the shunt pipe and the manifold;

[0013] The sealing terminal is arranged at the connection between the flow guide component and the shunt pipe; when the sealing terminal absorbs heat and changes from a solid state to a liquid state, the cooling liquid connected to the flow guide component enters the liquid flow channel through the shunt pipe.

[0014] Furthermore, the phase change temperature of the phase change material is lower than the melting point of the sealed terminal by more than 15° C.; and / or,

[0015] The flow guide assembly includes: a three-way joint and a liquid connecting pipe; the three-way joint is installed between the battery box water inlet and outlet pipes and the liquid cooling plate water inlet and outlet pipes, and the two ends of the liquid connecting pipe are respectively connected to the three-way joint and the diverter pipe.

[0016] Furthermore, in the cavity structure of the cover plate body, the thickness of the side away from the inside of the box body is greater than the thickness of the side facing the inside of the box body.

[0017] Furthermore, the energy storage battery box cover plate also includes: a heat-conducting aluminum strip, which is used to improve the heat transfer efficiency in the cover plate;

[0018] The heat-conducting aluminum strips are arranged on both sides and a middle position of the cover plate body, and the heat-conducting aluminum strips are connected to each other.

[0019] Furthermore, a high-temperature flame guide groove is provided on the side of the cover plate body facing the inside of the box body; the length direction of the high-temperature flame guide groove is perpendicular to the direction of the manifold.

[0020] Furthermore, the angle between the two side surfaces of the high-temperature flame guide groove is 120°-150°, and guide groove baffles are provided at both ends of the bottom of the high-temperature flame guide groove.

[0021] Further, the weight of the phase change material installed on the cover plate body is not less than 3 kg; and / or,

[0022] The phase change temperature of the phase change material is higher than 80°C.

[0023] Furthermore, the phase change material is magnesium chloride hexahydrate.

[0024] The beneficial effects of the present invention are:

[0025] The present invention combines the solid-liquid phase change characteristics of the phase change material and the flow and heat dissipation mechanism of the coolant, without the need for external signal control or power supply, to actively and efficiently absorb the heat released during thermal runaway of the battery; the phase change material remains solid at room temperature, effectively avoiding the risk of leakage that may be caused by liquid materials. Once heated, the phase change material will undergo a phase change and flow inside the cover plate, while the coolant also takes away heat through the preset flow channel. The synergistic effect of the two significantly reduces the heating intensity of the thermal runaway of the lower battery pack on the upper battery pack; the directional discharge design of the phase change material and the coolant ensures that there will be no pollution to the inside of the battery box or water ingress short circuit.

[0026] The energy storage battery box cover of the present invention not only effectively slows down the propagation speed of thermal runaway in the battery cluster, but also ensures the safety and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the overall structure of an energy storage battery box cover with a heat absorption function according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the exploded structure of an energy storage battery box cover with heat absorption function according to an embodiment of the present invention;

[0029] Figure 3 A side cross-sectional view of an energy storage battery box cover with a heat absorption function according to an embodiment of the present invention;

[0030] Figure 4 The figure is a schematic structural diagram of a manifold according to an embodiment of the present invention.

[0031] Among them, 1. cover plate; 11. cover plate body; 12. diverter pipe; 13. conduit; 131. directional pressure relief pipe; 14. thermal conductive aluminum strip; 15. phase change material installation cavity; 16. liquid flow channel; 17. high-temperature flame guide groove; 171. guide groove baffle; 2. phase change material; 3. guide assembly; 31. three-way joint; 32. liquid connecting pipe; 4. sealing terminal. DETAILED DESCRIPTION

[0032] The content of the present invention will now be discussed with reference to exemplary embodiments. It should be understood that the embodiments discussed are only to enable those skilled in the art to better understand and thus implement the content of the present invention, rather than implying any limitation on the scope of the present invention.

[0033] As used herein, the term “including” and variations thereof are to be interpreted as open-ended terms meaning “including, but not limited to.” The term “based on” is to be interpreted as “based, at least in part, on.” The terms “one embodiment” and “an embodiment” are to be interpreted as “at least one embodiment.”

[0034] Embodiment 1

[0035] Figure 1 This is a schematic diagram of the overall structure of an energy storage battery box cover with a heat absorption function according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the exploded structure of an energy storage battery box cover with heat absorption function according to an embodiment of the present invention; Figure 3 The figure is a side cross-sectional view of a cover plate of an energy storage battery box with heat absorption function according to an embodiment of the present invention. Figure 1-3 As shown, according to one embodiment of the present invention, a cover plate of an energy storage battery box with a heat absorption function comprises a cover plate 1, and the cover plate 1 comprises: a cover plate body 11, a manifold 13;

[0036] A phase change material installation chamber 15 for storing the phase change material 2 is provided inside the cover body 11. One end of the cover body 11 is connected to the manifold 13. An opening is provided at a position corresponding to the manifold 13 and the phase change material installation chamber 15.

[0037] When the phase change material 2 absorbs heat and changes its shape, it is discharged from the phase change material installation chamber 15 through the manifold 13 .

[0038] In this embodiment, the energy storage battery box cover with heat absorption function is applied to the top or side of the energy storage battery box. Preferably, this solution is applied to the top cover of the lithium battery energy storage box. The energy storage battery box cover with heat absorption function includes a cover 1 and a phase change material 2 installed in the cover; the cover 1 includes a cover body 11 and a manifold 13. The cover body 11 is made of aluminum profiles with openings at both ends, and a phase change material installation chamber 15 is designed inside for storing the phase change material 2. This design enables the cover 1 to effectively absorb heat.

[0039] One end of the cover plate body 11 is connected to the manifold 13, and the manifold 13 is provided with an opening at a position corresponding to the phase change material installation chamber 15. When the phase change material 2 undergoes a change in form due to the absorption of heat, such as from a solid to a liquid, the changed phase change material can be discharged from the phase change material installation chamber 15 through the opening of the manifold 13, thereby achieving heat transfer and release. The manifold 13 is located at the rear end of the cover plate 1, and the cover plate body 11 and the manifold 13 are connected by welding to ensure the stability and sealing of the structure.

[0040] The present invention uses built-in phase change material and its phase change process and the flow of liquid phase change material without additional signal control or power supply, so as to effectively absorb, transfer and release the heat in the battery box, significantly reduce the risk of thermal runaway, and delay the propagation speed of thermal runaway in the battery cluster. At the same time, its stable structure and optimized design enhance the strength and durability of the cover plate and improve the overall thermal management efficiency.

[0041] Figure 4 FIG. 1 is a schematic diagram of the structure of a manifold according to an embodiment of the present invention. Figure 4 As shown, according to one embodiment of the present invention, a directional pressure relief pipe 131 is provided on the manifold 13; the directional pressure relief pipe 131 is filled with paraffin for sealing.

[0042] In this embodiment, the manifold 13 is installed at the rear end of the cover plate 1 and is provided with a directional pressure relief pipe 131. The number of directional pressure relief pipes 131 can be multiple, and the specific number is set according to the needs. Figure 4 There are two of them. A small amount of paraffin is filled inside the directional pressure relief pipe 131, which is used as a sealing material. When the temperature rises, the paraffin will melt due to the temperature rise, thereby allowing the liquefied phase change material 2 to be discharged through the directional pressure relief pipe 131 to take away the heat.

[0043] The present invention arranges a directional pressure relief pipe on the manifold and fills it with paraffin as a sealing material, thereby realizing the function of melting the paraffin when the temperature rises, and the liquefied phase change material is discharged through the directional pressure relief pipe and takes away the heat, thereby effectively improving the thermal management efficiency and safety of the energy storage battery box.

[0044] According to one embodiment of the present invention, the energy storage battery box cover further includes: a flow guide component 3 and a sealing terminal 4; the sealing terminal 4 is made of a low melting point alloy;

[0045] The end of the cover body 11 away from the manifold 13 is connected to the shunt pipe 12, and a liquid flow channel 16 is provided inside the cover body 11; the two ends of the liquid flow channel 16 are respectively connected to the shunt pipe 12 and the manifold 13;

[0046] The sealed terminal 4 is arranged at the connection between the flow guide component 3 and the shunt tube 12 ; when the sealed terminal 4 absorbs heat and changes from solid to liquid, the coolant connected to the flow guide component 3 enters the liquid flow channel 16 through the shunt tube 12 .

[0047] In this embodiment, the energy storage battery box cover includes a cover 1, a phase change material 2, a flow guide assembly 3 and a sealing terminal 4; the cover 1 includes a cover body 11, a shunt tube 12 and a collector 13. The shunt tube 12 is located at the front end of the cover 1, and the collector 13 is located at the rear end of the cover 1; one end of the cover body 11 is connected to the shunt tube 12, and the other end is connected to the collector 13. A liquid flow channel 16 is provided inside the cover body 11, and the two ends of the liquid flow channel 16 are respectively connected to the shunt tube 12 and the collector 13. The shunt tube 12 is located at the front end of the cover and is connected to the flow guide assembly 3. One end of the flow guide assembly 3 is connected to the sealing terminal 4 provided inside the shunt tube 12 to form a sealing structure. The shunt tube 12 is provided with an opening at a position corresponding to the liquid flow channel 16 of the cover body. The sealing terminal 4 is made of a low melting point alloy material, welded inside the shunt tube 12, and matched with the flow guide assembly 3. When the sealed terminal 4 absorbs heat and changes from solid to liquid, the coolant connected to the flow guide component 3 can enter the liquid flow channel 16 through the shunt tube 12. In order to avoid contamination of the coolant system, the flow guide component 3 is a one-way flow, that is, the coolant can enter the shunt tube 12 through the flow guide component 3, and the liquid in the shunt tube 12 will not flow back through the flow guide component 3, and the coolant entering the shunt tube 12 flows out of the manifold 13 through the liquid flow channel 16. The manifold 13 is provided with openings at positions corresponding to the liquid flow channel 16 of the cover body 11 and the phase change material installation chamber 15 to facilitate the discharge of the coolant and the phase change material 2. The cover body 11 is connected to the shunt tube 12 and the manifold 13 by welding to ensure the stability and sealing of the structure.

[0048] The present invention integrates a flow guide component and a sealed terminal made of a low-melting-point alloy, so that after the sealed terminal is heated and melted, the coolant connected to the flow guide component can smoothly enter the liquid flow channel in the cover body and flow out through the manifold, effectively absorbing the heat of the battery box cover and improving the thermal management efficiency and safety of the energy storage battery box cover.

[0049] According to an embodiment of the present invention, the phase change temperature of the phase change material 2 is lower than the melting point of the sealed terminal 4 by more than 15°C.

[0050] In this embodiment, the phase change temperature of the phase change material 2 is set to be at least 15°C lower than the melting point of the low melting point alloy used for the sealed terminal 4. Ensure that when the temperature inside the battery box gradually increases and triggers the phase change of the phase change material 2, the sealed terminal 4 can still remain in a solid state and maintain the sealing structure between it and the flow guide component 3 and the shunt tube 12. When the temperature continues to rise, the paraffin in the directional pressure relief tube 131 melts, the phase change material 2 changes from a solid state to a liquid state, and the phase change material 2 flows out of the directional pressure relief tube 131 set on the manifold 13; when the temperature further rises and reaches or exceeds the melting point of the sealed terminal 4, the sealed terminal 4 melts, allowing the coolant to enter the liquid flow channel 16 through the shunt tube 12 and be discharged through the manifold 13, further cooling the battery box. Such a temperature difference setting not only ensures that the sealed terminal 4 can maintain sealing while the phase change material 2 works effectively, but also ensures that under extremely high temperatures, the system can automatically adjust the circulation of the coolant through the melting of the sealed terminal, achieving more flexible and efficient thermal management.

[0051] The present invention sets the phase change temperature of the phase change material at least 15°C lower than the melting point of the sealing terminal, thereby ensuring that the sealing terminal remains solid and maintains the seal when the phase change material is working effectively, while allowing the sealing terminal to melt at a higher temperature to automatically adjust the circulation of coolant, thereby achieving flexibility and efficiency in thermal management of the battery box, protecting battery safety and improving thermal response capabilities.

[0052] According to one embodiment of the present invention, the flow guide assembly 3 includes: a three-way connector 31 and a liquid connecting pipe 32;

[0053] The three-way joint 31 is installed between the water inlet and outlet pipes of the battery box and the water inlet and outlet pipes of the liquid cooling plate, and both ends of the liquid connecting pipe 32 are respectively connected to the three-way joint 31 and the shunt pipe 12.

[0054] In this embodiment, the flow guide assembly 3 includes a three-way joint 31 and a liquid connecting pipe 32, and the three-way joint 31 is installed between the inlet and outlet water pipes of the battery box and the inlet and outlet water pipes of the liquid cooling plate. The liquid connecting pipe 32 acts as a bridge, one end of which is tightly connected to the three-way joint 31, and the other end forms a reliable sealed connection with the shunt pipe 12 through the sealing terminal 4. Not only does it ensure the smooth flow of the coolant between the battery box and the liquid cooling plate, but also through the intelligent temperature control characteristics of the sealing terminal 4, it realizes the function of automatically opening the coolant flow path when the temperature rises. When the internal temperature of the battery box reaches or exceeds the melting point of the sealing terminal 4, the sealing terminal 4 melts, and the coolant (the liquid in the inlet and outlet water pipes of the battery box and the inlet and outlet water pipes of the liquid cooling plate) can smoothly enter the liquid flow channel 16 in the cover plate body 11 through the shunt pipe 12, thereby realizing precise cooling of the battery box.

[0055] The present invention integrates a three-way joint and a liquid connecting tube, combined with a sealed terminal with intelligent temperature control, to achieve flexible distribution and intelligent regulation of the coolant between the battery box and the liquid cooling plate. When the temperature rises to the melting point of the sealed terminal, the coolant flow path is automatically opened to accurately cool the battery box, which significantly improves the thermal management efficiency and intelligence level.

[0056] According to an embodiment of the present invention, in the cavity structure of the cover plate body 11 , the thickness of the side away from the interior of the box body is greater than the thickness of the side facing the interior of the box body.

[0057] In this embodiment, the thickness of the top of the cover plate 1 is greater than the thickness of the bottom. Since the cover plate body 11 is provided with a cavity inside, including but not limited to the phase change material installation chamber 15 and the liquid flow channel 16, the material thickness of the side of the cover plate body 11 away from the inside of the energy storage battery box is greater than the thickness of the side close to the inside of the box, that is, the material thickness of the top of the cavity (including the phase change material installation chamber 15 and the liquid flow channel 16) is greater than the material thickness of the bottom.

[0058] According to one embodiment of the present invention, the energy storage battery box cover plate further comprises: a heat-conducting aluminum strip 14, which is used to improve the heat transfer efficiency in the cover plate 1;

[0059] The heat-conducting aluminum bars 14 are disposed on both sides and the middle of the cover body 11 , and the heat-conducting aluminum bars 14 are connected to each other.

[0060] In this embodiment, the energy storage battery box cover also includes a heat-conducting aluminum strip 14 for improving the heat transfer efficiency in the cover 1; the heat-conducting aluminum strips 14 are arranged on both sides and in the middle of the cover body 11, and these heat-conducting aluminum strips are interconnected to form an efficient heat transfer network. The heat-conducting aluminum strips 14 and the heat-conducting aluminum strips 14 and the cover body 11 are connected by welding. When heat is generated inside the battery box, the heat-conducting aluminum strips 14 can quickly absorb and disperse the heat, and through their excellent thermal conductivity, the heat is efficiently transferred to other parts of the cover, thereby effectively reducing the temperature inside the battery box and improving the heat transfer efficiency.

[0061] The present invention forms an efficient heat transfer network by arranging interconnected heat-conducting aluminum strips in the cover plate of the energy storage battery box, which significantly improves the heat transfer efficiency and effectively reduces the internal temperature of the battery box.

[0062] According to an embodiment of the present invention, a high temperature flame guide groove 17 is provided on the side of the cover plate body 11 facing the inside of the box; the length direction of the high temperature flame guide groove 17 is perpendicular to the direction of the manifold 13 .

[0063] Preferably, the angle between the two side surfaces of the high-temperature flame guide groove 17 is 120°-150°, and guide groove baffles 171 are provided at both ends of the bottom of the high-temperature flame guide groove 17 .

[0064] In this embodiment, a high-temperature flame guide groove 17 is provided on one side of the cover body 11 facing the inside of the box, and its length direction is perpendicular (here, perpendicular only represents the direction, which may not be completely equal to 90°) to the direction of the manifold 13 to optimize the guidance and dispersion of the high-temperature flame or hot gas. The angle between the two sides of the high-temperature flame guide groove 17 is preferably set to 120°-150°. This design helps the flame or hot gas to form a more stable flow path in the groove. In addition, guide groove baffles 171 are also provided at both ends of the bottom of the guide groove to further enhance the guidance and control of the flame or hot gas. At the same time, heat-conducting aluminum strips 14 are installed at the top of the high-temperature flame guide groove 17 and other key positions of the cover body 11, such as the two ends and the middle of the length direction. These heat-conducting aluminum strips 14 not only enhance the heat transfer efficiency inside the cover 1, but also quickly disperse the heat when the flame or hot gas contacts, reducing the risk of local high temperature.

[0065] The present invention provides a high-temperature flame guide groove and a matching guide groove baffle in the energy storage battery box cover, which not only achieves effective guidance and dispersion of high-temperature flames or hot air, but also reduces the safety risks caused by high temperature inside the battery box, improves the heat transfer efficiency, and provides a more reliable guarantee for the safe operation of the battery system.

[0066] According to one embodiment of the present invention, the weight of the phase change material 2 installed on the cover body 11 is not less than 3 kg; and / or,

[0067] The phase change temperature of the phase change material 2 is higher than 80°C.

[0068] Preferably, the phase change material 2 is magnesium chloride hexahydrate.

[0069] In this embodiment, a phase change material 2 weighing not less than 3 kg is installed on the cover body 11, and its phase change temperature is higher than 80°C. The phase change material 2 is preferably magnesium chloride hexahydrate, and its phase change temperature is 114°C-120°C. When the temperature inside the battery box rises, the magnesium chloride hexahydrate begins to absorb heat and gradually changes from solid to liquid. This phase change process can absorb a large amount of heat, thereby effectively slowing down the rate of increase of the temperature inside the battery box.

[0070] The present invention significantly enhances the thermal management capability of the energy storage battery box, and effectively slows down the temperature rise rate inside the battery box through the heat absorption and phase change process of the phase change material, providing a more reliable thermal safety guarantee for the long-term stable operation of the battery system.

[0071] The present invention has a passive heat absorption function, which directly absorbs the heat released by thermal runaway of lithium batteries through the solid-liquid phase change of phase change materials and the flow of cooling water, thereby effectively reducing the heating intensity of the upper battery pack after the lower battery pack has thermal runaway, and delaying the propagation speed of thermal runaway in the battery cluster. The phase change material filled inside the box cover is solid at room temperature, avoiding the risk of leakage caused by liquid materials. After heating, the phase change material and cooling water flow inside the cover and are discharged in a direction, which will not cause pollution to the inside of the battery box, and will not cause water ingress short circuit.

[0072] The present invention does not require signal control or power supply, but directly relies on the phase change of the phase change material and the flow of coolant to absorb heat, thereby reducing the heating intensity of the upper battery pack after the lower battery pack has thermal runaway, and effectively delaying the propagation speed of thermal runaway in the battery cluster.

[0073] Embodiment 2

[0074] like Figure 1-4 As shown, according to one embodiment of the present invention, a cover plate of an energy storage battery box with a heat absorption function comprises a cover plate 1, a phase change material 2 installed in the cover plate 1, a flow guide component 3, and a sealing terminal 4;

[0075] The flow guide assembly 3 includes a three-way joint 31 and a liquid connecting pipe 32. The three-way joint 31 is installed between the battery box water inlet and outlet pipes and the liquid cooling plate water inlet and outlet pipes. One end of the liquid connecting pipe 32 is connected to the three-way joint 31, and the other end is installed with a sealing terminal 4.

[0076] The phase change material 2 is selected as magnesium chloride hexahydrate, the weight of the phase change material 2 is 4.2kg, it is solid at room temperature, and it is installed in the phase change material installation cavity 15 inside the cover plate 1. The phase change temperature of the phase change material 2 is 114℃-120℃. The low melting point alloy is selected as Bi-Sn alloy with a melting point of 138℃-150℃. The sealed terminal 4 made of low melting point alloy is welded and installed in the shunt tube 12, and the liquid connecting tube 32 is respectively connected to the sealed terminal 4 and the three-way joint 31. The three-way joint 31 is connected to the battery pack liquid cooling pipe, specifically between the battery pack inlet and outlet pipes and the liquid cooling plate inlet and outlet pipes. The three-way joint 31 is installed on the battery box.

[0077] The cover plate 1 includes a cover plate body 11, a shunt pipe 12, a manifold 13, and a heat-conducting strip 14. The cover plate body 11 is an aluminum profile that contains a phase change material installation cavity 15 and a liquid flow channel 16. The cover plate body 11 is provided with a high-temperature flame guide groove 17 and a heat-conducting aluminum strip 14 on the side facing the inside of the box body, and heat-conducting aluminum strips 14 are also installed at both ends and the middle of the cover plate body 11. The two sides of the cover plate body 11 are respectively welded to the aluminum shunt pipe 12 and the aluminum manifold 13, and a sealing terminal 4 is welded inside the shunt pipe 12, and the sealing terminal 4 is installed at one end of the liquid connecting pipe 32.

[0078] The phase change material installation cavity 15 inside the cover body 11 is filled with magnesium chloride hexahydrate (phase change material 2), and the phase change material 2 is solid at room temperature; at the same time, a liquid flow channel 16 is reserved in the cover body 11, and one end of the liquid flow channel 16 is connected to the sealing terminal 4 in the shunt tube 12.

[0079] An opening is provided in the flow distribution pipe 12 at a position corresponding to the liquid flow channel 16 of the cover plate body 11 .

[0080] The manifold 13 has openings at positions corresponding to the phase change material installation cavity 15 and the liquid flow channel 16 of the cover body 11. Directional pressure relief pipes 131 are installed at both ends of the manifold 13. The directional pressure relief pipes 131 open downward. A small amount of sealing paraffin is filled in the directional pressure relief pipes 131.

[0081] The present invention integrates sealed terminals made of phase change material and low melting point alloy on the cover of the energy storage battery box, combines the guide component and the specific cover structure design, realizes heat absorption, heat conduction and safe pressure relief functions, and effectively improves the thermal management performance and safety of the battery box.

[0082] The working principle of the present invention is as follows:

[0083] 1. When a battery in the battery pack experiences thermal runaway, the high-temperature gas or flame ejected from the battery safety valve enters the high-temperature flame guide groove 17 and flows rapidly along the length direction of the high-temperature flame guide groove 17, causing the temperature of the side wall of the high-temperature flame guide groove 17, the baffle plate 171 at the bottom of the guide groove, and the heat-conducting aluminum strip 14 to rise sharply. The heat is conducted in the cover body 11.

[0084] 2. The cover plate is made of aluminum profile, which has good thermal conductivity. The wall temperature of the phase change material installation cavity 15 continues to rise. When the temperature reaches the melting point of magnesium chloride hexahydrate (114℃-120℃), magnesium chloride hexahydrate melts from solid to liquid. Due to the large latent heat of phase change of magnesium chloride hexahydrate, it absorbs a large amount of heat from thermal runaway of the battery.

[0085] 3. The magnesium chloride hexahydrate is continuously absorbed by the phase change latent heat of magnesium chloride hexahydrate, and the magnesium chloride hexahydrate in the phase change material installation cavity 15 gradually changes from solid to liquid. The sealing paraffin in the directional pressure relief pipe 131 automatically flows out after melting. The liquid magnesium chloride hexahydrate flows along the manifold 13 to the directional pressure relief pipe 131, and flows out from the directional pressure relief pipe 131.

[0086] 4. When the high-temperature gas or flame ejected by the battery heats the cover plate 1, the heat-conducting aluminum strip 14 on the top of the high-temperature flame guide groove 17 and the cover plate body 11 itself also transfer heat to the sealed terminal 4 inside the shunt tube 12. When the temperature reaches the melting point of the low-melting-point alloy (Bi-Sn alloy, the melting point is 138°C-150°C), the sealed terminal 4 melts, and the liquid connecting tube 32 and the cover plate 1 form a flow channel.

[0087] The coolant of the liquid cooling system enters the liquid flow channel 16 in the cover plate body 11 through the three-way joint 31, the liquid connecting pipe 32 and the diverter pipe 12. The coolant continues to absorb heat to cool the cover plate 1 and reduce the temperature of the cover plate 1. The coolant finally flows out from the directional pressure relief pipe 131 of the manifold 13.

[0088] In a specific embodiment of the present invention, the heat-conducting aluminum strips 14 are located on both sides and in the middle of the cover plate body 11, and the heat-conducting aluminum strips 14 are connected to each other, which can improve the heat transfer efficiency in the cover plate 1. When any battery has thermal runaway and ejects high-temperature gas or high-temperature flame, the heat can be quickly transferred to various parts of the cover plate 1 under the heat conduction of the cover plate body 11 and the heat-conducting aluminum strips 14, accelerating the phase change endothermic process of magnesium chloride hexahydrate and the melting process of the low-melting-point alloy.

[0089] The energy storage battery box cover with heat absorption function of the present invention is passive, does not require signal control or power supply, and directly relies on the phase change of phase change material and the flow of coolant to absorb heat, thereby reducing the heating intensity of the upper battery pack after the battery pack located at the lower layer has thermal runaway, and delaying the propagation speed of thermal runaway in the battery cluster.

[0090] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

[0091] It should be understood that the size of the serial numbers of each step in the content of the invention and the embodiments of the present invention does not absolutely mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Claims

1. A cover plate for an energy storage battery box with a heat absorption function, comprising a cover plate (1), characterized in that: The cover plate (1) comprises: a cover plate body (11), a manifold (13); A phase change material installation chamber (15) for storing the phase change material (2) is provided inside the cover plate body (11); one end of the cover plate body (11) is connected to the manifold (13); an opening is provided at a position corresponding to the manifold (13) and the phase change material installation chamber (15); When the phase change material (2) absorbs heat and changes its form, it is discharged from the phase change material installation chamber (15) through the manifold (13).

2. The energy storage battery box cover with heat absorption function according to claim 1 is characterized in that: The manifold (13) is provided with a directional pressure relief pipe (131); the directional pressure relief pipe (131) is filled with paraffin wax for sealing.

3. The energy storage battery box cover with heat absorption function according to claim 1, characterized in that: The energy storage battery box cover also includes: a flow guide component (3) and a sealing terminal (4); the sealing terminal (4) is made of a low melting point alloy; One end of the cover plate body (11) facing away from the manifold (13) is connected to a flow diversion pipe (12), and a liquid flow channel (16) is provided inside the cover plate body (11); two ends of the liquid flow channel (16) are respectively connected to the flow diversion pipe (12) and the manifold (13); The sealed terminal (4) is arranged at the connection between the flow guide component (3) and the shunt tube (12); when the sealed terminal (4) absorbs heat and changes from a solid state to a liquid state, the cooling liquid connected to the flow guide component (3) enters the liquid flow channel (16) through the shunt tube (12).

4. The energy storage battery box cover with heat absorption function according to claim 3 is characterized in that: The phase change temperature of the phase change material (2) is lower than the melting point of the sealed terminal (4) by more than 15° C.; and / or, The flow guide assembly (3) comprises: a three-way joint (31) and a liquid connecting pipe (32); the three-way joint (31) is installed between the battery box water inlet and outlet pipes and the liquid cooling plate water inlet and outlet pipes, and the two ends of the liquid connecting pipe (32) are respectively connected to the three-way joint (31) and the diverter pipe (12).

5. The energy storage battery box cover with heat absorption function according to claim 1 is characterized in that: In the cavity structure of the cover plate main body (11), the thickness of the side away from the inside of the box body is greater than the thickness of the side facing the inside of the box body.

6. The energy storage battery box cover with heat absorption function according to claim 1, characterized in that: The energy storage battery box cover plate further comprises: a heat-conducting aluminum strip (14) for improving the heat transfer efficiency in the cover plate (1); The heat-conducting aluminum strips (14) are arranged on both sides and a middle position of the cover plate body (11), and the heat-conducting aluminum strips (14) are connected to each other.

7. The energy storage battery box cover with heat absorption function according to claim 1 is characterized in that: A high-temperature flame guide groove (17) is provided on the side of the cover plate body (11) facing the interior of the box body; the length direction of the high-temperature flame guide groove (17) is perpendicular to the direction of the manifold (13).

8. The energy storage battery box cover with heat absorption function according to claim 7 is characterized in that: The angle between the two side surfaces of the high-temperature flame guide groove (17) is 120°-150°, and guide groove baffles (171) are provided at both ends of the bottom of the high-temperature flame guide groove (17).

9. The energy storage battery box cover with heat absorption function according to claim 1, characterized in that: The phase change material (2) installed on the cover plate body (11) weighs no less than 3 kg; and / or, The phase change temperature of the phase change material (2) is higher than 80°C.

10. The energy storage battery box cover with heat absorption function according to claim 9, characterized in that: The phase change material (2) is magnesium chloride hexahydrate.

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