Battery packs and battery systems

Abstract

The present invention provides a battery pack and battery system that reduces temperature differences on the battery surface, avoids localized heat buildup in the battery, makes the temperature distribution throughout the battery more uniform, and reduces the risk of battery performance degradation and shortened lifespan due to temperature differences. [Solution] The battery pack 10 includes a housing 100 having a housing space inside which a immersion liquid is arranged to be contained, and a first end 110 and a second end 120 having a first liquid outlet installed opposite each other; a battery 200 installed in the housing space; and a liquid cooling plate 300 adjacent to the housing, having an interior that contains a cooling liquid, and having a third end 310 and a fourth end 320 having a second liquid outlet installed opposite each other. Here, the first end is adjacent to the third end, and the second end is adjacent to the fourth end.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the priority of Chinese Patent Applications with application numbers 2024113718235 and 2024223867867, filed with the Chinese Patent Office on September 27, 2024. All the contents of the above applications are incorporated herein by reference.

[0002] Technical Field This application relates to the field of battery technology, particularly to battery packs and battery systems.

Background Art

[0003] In a lithium - battery system, thermal management technology is an important factor in ensuring battery performance and safety. Current battery packs mainly adopt two types of thermal management methods: indirect liquid cooling and immersion cooling.

Summary of the Invention

Problems to be Solved by the Invention

[0004] For indirect liquid cooling, due to the limited contact area between the cooling working substance and the cell, the heat dissipation effect is limited, and it is difficult to meet the demand for high - power charge - discharge. On the other hand, immersion cooling can increase the contact area between the battery and the cooling working substance and improve the uniform - temperature performance. However, due to immersion cooling, the liquid does not flow, and heat cannot be effectively removed, which also affects the heat dissipation effect.

Means for Solving the Problems

[0005] According to a first aspect, the present invention provides a battery pack comprising: a housing having a storage space inside which a immersion liquid is disposed to contain the immersion liquid, and having a first end on which a first liquid inlet is provided and a second end on which a first liquid outlet is provided, both of which are installed opposite each other; a battery installed in the storage space; and a liquid cooling plate adjacent to the housing, having a cooling liquid inside which a coolant is disposed, and having a third end on which a second liquid outlet is provided and a fourth end on which a second liquid inlet is provided, both of which are installed opposite each other, wherein the first end is adjacent to the third end, and the second end is adjacent to the fourth end.

[0006] According to a second aspect, the present invention provides a battery system comprising a control assembly and a battery pack as described above, wherein the control assembly is connected to the battery pack. [Effects of the Invention]

[0007] The beneficial effects of this invention are as follows: With respect to the battery in the housing, a cooling medium at a relatively low temperature can effectively assist in cooling the battery at either the first or second end of the housing. In this embodiment, by carefully arranging the relative positions between the first liquid inlet and first liquid outlet of the immersion liquid and the second liquid inlet and second liquid outlet of the cooling liquid, the immersion liquid and cooling liquid of the battery pack act synergistically, allowing the battery to be sufficiently cooled in different areas, ensuring that the heat from the battery is distributed more uniformly and effectively, reducing temperature differences on the battery surface, avoiding localized heat accumulation in the battery, making the temperature distribution of the entire battery more uniform, and reducing the risk of battery performance degradation and shortened lifespan due to temperature differences. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram of the structure of the first type of battery pack according to an embodiment of the present invention. [Figure 2] This is a schematic internal cross-sectional view of a battery pack according to an embodiment of the present invention. [Figure 3] This is a schematic diagram of the second type of battery pack according to an embodiment of the present invention. [Figure 4]This is a schematic diagram of the battery pack from a different angle, as shown in Figure 1. [Figure 5] This is a schematic diagram of the third type of battery pack according to an embodiment of the present invention. [Figure 6] Figure 5 is a schematic diagram of the battery pack from a different angle. [Figure 7] This is a cross-sectional view of the battery pack along AA shown in Figure 6. [Figure 8] This is a schematic diagram of the fourth type of battery pack according to an embodiment of the present invention. [Figure 9] Figure 8 is a schematic diagram of the battery pack from a different angle. [Figure 10] Figure 8 is a schematic diagram of the battery pack from yet another angle. [Figure 11] Figure 8 shows a cross-sectional view of the battery pack along the ball bearing (BB). [Modes for carrying out the invention]

[0009] Referring to Figure 1, Figure 1 is a schematic diagram of the structure of a first type of battery pack according to an embodiment of the present invention. The battery pack 10 of this embodiment employs a combination of two methods: indirect liquid cooling and immersion cooling, to provide a more effective thermal management system. Here, the battery pack 10 includes a housing 100, a battery 200, and a liquid cooling plate 300.

[0010] The housing 100 is the external structure of the battery pack 10 and is positioned to protect the internal battery 200 and the immersion cooling system. Inside the housing 100 is a containment space arranged to hold the immersion liquid, which can come into direct contact with the battery 200 within the containment space. The housing 100 has a first end 110 and a second end 120 that are positioned opposite each other. A first liquid inlet 130 is provided at the first end 110 and a first liquid outlet 140 is provided at the second end 120. When the immersion liquid is injected into the containment space of the housing 100 by the first liquid inlet 130, it is in a relatively low temperature state, and as the immersion liquid flows into the containment space, it comes into direct contact with the battery 200, causing the temperature of the immersion liquid to gradually rise and then be discharged from the first liquid outlet 140. In this embodiment, since the immersion liquid inside the housing 100 is flowing, heat can be removed more effectively and the heat dissipation effect can be improved.

[0011] The battery 200 is the core part of the battery pack 10, installed within the housing space, and surrounded by the immersion liquid. The heat generated during charging and discharging of the battery 200 is effectively dissipated by the immersion liquid. The material system of the battery 200 is not limited; it may be a ternary lithium battery, a lithium iron phosphate battery, or a manganese iron lithium phosphate battery. The battery 200 may be a prismatic battery, a cylindrical battery, a soft pack battery, etc.

[0012] The liquid cooling plate 300 is adjacent to the housing 100 and indirectly contacts the battery 200. The liquid cooling plate 300 may be located on the side, top, or bottom of the housing 100, and the liquid cooling plate 300 shown in the attached drawing is located at the bottom of the housing 100. Coolant is contained inside the liquid cooling plate 300, and the coolant flows inside the liquid cooling plate 300, absorbing and removing heat transferred from the battery 200 to the liquid cooling plate 300. The liquid cooling plate 300 has a third end 310 and a fourth end 320 which are similarly installed opposite each other. A second liquid outlet 340 is installed at the third end 310, and a second liquid inlet 330 is installed at the fourth end 320. The coolant enters the liquid cooling plate 300 through the second liquid inlet 330. Upon entering the liquid cooling plate 300, the coolant is at a relatively low temperature. As the coolant flows through the liquid cooling plate 300, it absorbs the heat transferred from the battery 200 to the liquid cooling plate 300, causing the temperature of the coolant to gradually rise before being discharged from the second liquid outlet 340.

[0013] Here, the first end 110 is adjacent to the third end 310, and the second end 120 is adjacent to the fourth end 320. Therefore, the first liquid inlet 130 of the immersion liquid and the second liquid outlet 340 of the coolant are relatively close, and the first liquid outlet 140 of the immersion liquid and the second liquid inlet 330 of the coolant are also relatively close. As can be seen, the temperature of the immersion liquid at the first liquid outlet 140 of the second end 120 is relatively high, which is unfavorable for heat dissipation in the vicinity of the second end 120 of the housing 100. Therefore, a coolant with a relatively lower temperature is injected into the nearby second liquid inlet 330, and this relatively lower temperature coolant can effectively help in heat dissipation and temperature reduction in the vicinity of the second end 120.

[0014] Similarly, the temperature of the cooling liquid at the second liquid outlet 340 of the third end 310 is relatively high, which is disadvantageous for the third end 310 of the liquid cooling plate 300 to absorb the heat of the first end 110 of the adjacent housing 100. However, in the nearby first liquid inlet 130, a dipping liquid with a relatively low temperature is injected, and the dipping liquid with a relatively low temperature can effectively help with heat dissipation and temperature reduction in the vicinity of the first end 110. Therefore, for the battery 200 in the housing 100, in either the first end 110 or the second end 120 of the housing 100, a cooling medium with a relatively low temperature can always effectively help cool the battery 200.

[0015] In this embodiment, by carefully arranging the relative positions among the first liquid inlet 130 and the first liquid outlet 140 of the dipping liquid and the second liquid inlet 330 and the second liquid outlet 340 of the cooling liquid, the dipping liquid and the cooling liquid of the battery pack 10 act synergistically, the battery 200 can be sufficiently cooled in different regions, the heat generated by the battery 200 is ensured to be more uniformly and effectively dispersed, the temperature difference on the surface of the battery 200 is reduced, local heat accumulation in the battery 200 is avoided, the temperature distribution of the entire battery 200 is made more uniform, and the risk of performance degradation and shortened lifespan of the battery 200 due to the temperature difference is reduced.

[0016] It should be noted that in this embodiment, it may be understood that the liquid cooling plate 300 is adjacent to the housing 100 and the liquid cooling plate 300 can be adjacent to either side of the housing 100. Exemplarily, the liquid cooling plate 300 can be adjacent to the top plate, the bottom plate or any other side of the housing 100. And the housing 100 is considered to include two ends, namely the first end 110 and the second end 120, in any of the longitudinal direction, the width direction and the height direction. Similarly, the liquid cooling plate 300 is considered to include two ends, namely the third end 310 and the fourth end 320, in any of the longitudinal direction, the width direction and the height direction.

[0017] Referring to FIG. 2, FIG. 2 is a schematic internal cross-sectional view of the battery 200 according to an embodiment of the present application.

[0018] In some embodiments, the distance between the first liquid inlet 130 and the second liquid outlet 340 is L1. The distance L1 is measured by inserting a caliper into the first liquid inlet 130 and the second liquid outlet 340 respectively. Of course, the distance between the first liquid inlet 130 and the second liquid outlet 340 may also be measured by a measuring tool such as a straightedge. 1 cm ≤ L1 ≤ 10 cm, and L1 may be 1 cm, 2 cm, 3 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, etc. Within this range, it can be ensured that sufficient heat exchange occurs between the coolant in the liquid cooling plate 300 and the immersion liquid in the housing 100, and the effect of heat equalization can be achieved.

[0019] In some embodiments, the distance between the first liquid outlet 140 and the side of the housing 100 away from the liquid cooling plate 300 is L2. L2 is the distance from the first liquid outlet 140 to the upper surface of the housing 100. The distance L2 is measured by inserting a caliper into the first liquid outlet 140 and then wrapping it around the upper surface of the housing 100. Of course, the distance between the first liquid outlet 140 and the upper surface of the housing 100 may also be measured by a measuring tool such as a straightedge. 15 cm ≤ L2 ≤ 22 cm, and L2 may be 15 cm, 16 cm, 17 cm, 18 cm, 19 cm, 20 cm, 21 cm, 22 cm, etc. Within the above range, the first liquid outlet 140 can be made higher than the height of accessories such as the aluminum row above the battery 200, ensuring that all the immersion liquid immerses the battery 200. If it exceeds this range, the immersion liquid that has absorbed heat has a relatively low density in the accommodation space and is difficult to float and be discharged naturally.

[0020] In some embodiments, the distance between the second liquid inlet 330 and the side of the liquid cooling plate 300 closer to the housing 100 is L3, where L3 may be the distance between the second liquid inlet 330 and the housing 100, and the distance between the second liquid outlet 340 and the side of the liquid cooling plate 300 closer to the housing 100 is L4, where L4 may be the distance between the second liquid outlet 340 and the housing 100, where L4 ≤ L3, i.e., the second liquid inlet 330 is further from the housing 100 than the second liquid outlet 340, and the second liquid inlet 330 is lower than the second liquid outlet 340, thereby ensuring that the coolant can be immersed in the liquid cooling plate 300 to the maximum extent. Also, 2cm ≤ L4 ≤ 6cm, where L4 may be 2cm, 3cm, 4cm, 5cm, 6cm, etc.

[0021] In some embodiments, the height of the housing 100 is H1, where H1 is the distance between the top and bottom surfaces of the housing 100, and the height of the liquid cooling plate 300 is H2, where H2 is the distance between the top and bottom surfaces of the liquid cooling plate 300, with 2 ≤ H1 / H2 ≤ 5, where H1 / H2 may be 2, 3, 4, 5, etc. The height of the housing 100 is between 2 and 5 times the height of the liquid cooling plate 300, and furthermore, the immersion liquid inside the housing 100 is between 2 and 5 times the coolant inside the liquid cooling plate 300, thereby ensuring sufficient heat exchange between the coolant in the liquid cooling plate 300 and the immersion liquid inside the housing 100, and achieving a uniform heat effect.

[0022] In some embodiments, the length of the housing 100 is D1, where D1 is the distance between the left and right sides of the housing 100, and the length of the liquid cooling plate 300 is D2, where D2 is the distance between the left and right sides of the liquid cooling plate 300, with 15cm ≤ D1-D2 ≤ 22cm, where D1-D2 is the shortest distance of the liquid cooling plate 300 relative to the housing 100, and may be 15cm, 16cm, 17cm, 18cm, 19cm, 20cm, 21cm, 22cm, etc. The liquid cooling plate 300 is shorter than the housing 100, creating an empty space next to the housing 100, within which connection space can be reserved for the piping of the first liquid inlet 130 and the first liquid outlet 140 on the adjacent housing 100, while ensuring the space utilization rate of the battery 200 system.

[0023] Referring to Figure 3, Figure 3 is a schematic diagram of the second type of battery pack structure according to an embodiment of the present invention. In this embodiment, the position of the first electrolyte inlet 130 at the first end 110, the position of the first electrolyte outlet 140 at the second end 120, the position of the second electrolyte inlet 330 at the fourth end 320, and the position of the second electrolyte outlet 340 at the third end 310 can be adjusted as needed for the layout. In Figures 1 and 3, the position of the first electrolyte inlet 130 at the first end 110 is different, but in both cases it is located at the first end 110. Similarly, in Figures 1 and 3, the position of the first electrolyte outlet 140 at the second end 120 is also different, but in both cases it is located at the second end 120. This embodiment is not limited to this, but even if the first end 110 where the first liquid inlet 130 is installed is adjacent to the third end 310 where the second liquid outlet 340 is installed, and the second end 120 where the first liquid outlet 140 is installed is adjacent to the fourth end 320 where the second liquid inlet 330 is installed, the synergistic effect between the immersion liquid and the cooling liquid allows the battery 200 to dissipate heat more uniformly and effectively.

[0024] In some embodiments, referring to Figure 4, which is a schematic diagram of the structure of the battery pack shown in Figure 1 from a different angle. Along the longitudinal direction of the housing 100, the first end 110 includes a first end plate 111, the second end 120 includes a second end plate 121, the first end plate 111 and the second end plate 121 are installed facing each other, the first liquid inlet 130 is installed on the first end plate 111, and the first liquid outlet 140 is installed on the second end plate 121, along the longitudinal direction of the liquid cooling plate 300, the third end 310 is the third The end plate 311 is included, and the fourth end plate 320 includes the fourth end plate 321, with the third end plate 311 and the fourth end plate 321 facing each other, the second liquid outlet 340 being installed on the third end plate 311, and the second liquid inlet 330 being installed on the fourth end plate 321, the third end plate 311 and the first end plate 111 being on the same side, and the second end plate 121 and the fourth end plate 321 being on the same side.

[0025] In this embodiment, the housing 100 has two ends along its longitudinal direction, and the first end 110 is located at one end of the housing 100 and includes one first end plate 111, on which a first liquid inlet 130 for immersion liquid is provided, which is arranged to inject a low-temperature immersion liquid. The second end 120 is located at the other opposite end of the housing 100 and includes one second end plate 121, on which a first liquid outlet 140 for immersion liquid is provided, which is arranged to discharge the immersion liquid that has absorbed heat and whose temperature has risen. Similarly, the liquid cooling plate 300 also has two ends along its longitudinal direction, and the third end 310 is located at one end of the liquid cooling plate 300 and includes one third end plate 311, on which a second liquid outlet 340 for coolant is provided, which is arranged to discharge the coolant that has absorbed heat and whose temperature has risen. The fourth end 320 is located at the other opposite end of the liquid cooling plate 300 and includes a fourth end plate 321, the fourth end plate 321 of which a second coolant inlet 330 is provided, which is arranged to inject a low-temperature coolant. That is, in this embodiment, the first liquid inlet 130 and the first liquid outlet 140 are installed along the longitudinal direction of the housing 100, and the second liquid inlet 330 and the second liquid outlet 340 are also installed along the longitudinal direction of the liquid cooling plate 300, allowing for a longer flow path for the immersion liquid and coolant, which in turn allows for more time to absorb and remove heat during the flow process, enabling more effective heat dissipation.

[0026] Here, the third end plate 311 and the first end plate 111 are located on the same side, and the second end plate 121 and the fourth end plate 321 are located on the same side. Therefore, the second liquid outlet 340 of the coolant and the first liquid inlet 130 of the immersion liquid are on the same side and are relatively close in terms of spatial layout, and the second liquid inlet 330 of the coolant and the first liquid outlet 140 of the immersion liquid are also on the same side and are relatively close in terms of spatial layout. As can be understood, the temperature of the immersion fluid is relatively high in the vicinity of the first liquid outlet 140, but the temperature of the coolant is relatively low in the vicinity of the second liquid inlet 330 on the same side, and the temperature of the coolant is relatively high in the vicinity of the second liquid outlet 340, but the temperature of the immersion fluid is lower in the vicinity of the first liquid inlet 130 on the same side. Therefore, the cooling medium, which is always at a relatively low temperature in different regions of the battery 200, absorbs heat, helps to distribute the heat from the battery 200 more uniformly and effectively, and helps to avoid localized heat accumulation in the battery 200.

[0027] In some embodiments, continuing to refer to Figures 1 and 3, the flow direction of the coolant in the liquid cooling plate 300 is opposite to the flow direction of the immersion liquid in the housing 100. As can be seen, in this embodiment, while the immersion liquid is injected into the housing 100 from the first liquid inlet 130 of the first end 110 and discharged from the first liquid outlet 140 of the second end 120, the coolant is simultaneously injected into the liquid cooling plate 300 from the second liquid inlet 330 of the fourth end 320 and discharged from the second liquid outlet 340 of the third end 310. Since the first end 110 is adjacent to the third end 310 and the second end 120 is adjacent to the fourth end 320, the flow direction of the coolant in the liquid cooling plate 300 may be opposite to the flow direction of the immersion liquid in the housing 100.

[0028] To make it easier to understand, along the flow direction of the immersion liquid in the housing 100, the immersion liquid absorbs heat from the battery 200 during its flow and its temperature gradually rises. Similarly, along the flow direction of the coolant in the liquid cooling plate 300, the coolant absorbs heat on the liquid cooling plate 300 and its temperature rises. Since the flow direction of the coolant in the liquid cooling plate 300 is opposite to the flow direction of the immersion liquid in the housing 100, the temperature change trends of the immersion liquid in the housing 100 and the temperature change trends of the coolant in the liquid cooling plate 300 are opposite to those of the battery 200. In different regions on both sides of the battery 200, the cooling medium is always at a relatively lower temperature, absorbing heat. For example, on one side of the battery 200, the immersion fluid temperature is relatively high and the cooling fluid temperature is relatively low, while on the other side, the cooling fluid temperature is relatively high and the immersion fluid temperature is relatively low. This helps to distribute the heat from the battery 200 more uniformly and effectively, reducing the temperature difference on the surface of the battery 200 and avoiding localized heat buildup in the battery 200.

[0029] For example, the liquid cooling plate 300 is adjacent to the bottom plate of the housing 100, the immersion liquid enters from the first end plate 111 on the left side of the housing 100, the flow direction of the immersion liquid is from left to right, the initial temperature is relatively low, and as it absorbs heat from the battery 200, its temperature gradually rises along the left-to-right direction. The coolant enters from the fourth end plate 321 on the right side of the liquid cooling plate 300, the flow direction of the coolant is from right to left, the initial temperature is also relatively low, and as it absorbs heat from the battery 200, its temperature gradually rises along the right-to-left direction. In the process where the two cooling media, the immersion fluid and the coolant, flow simultaneously, the temperature of the immersion fluid is relatively low in the region closer to the left side of the battery 200 and relatively high in the region closer to the right side of the battery 200. At the same time, the temperature of the coolant is relatively high in the region closer to the left side of the battery 200 and relatively low in the region closer to the right side of the battery 200. The immersion fluid and the coolant can form a dynamic balance of heat exchange on both sides of the battery 200. The temperature of the immersion fluid is relatively high in the region closer to the right side of the battery 200, which is unfavorable for heat dissipation in that region. However, the temperature of the coolant in the region closer to the right side of the battery 200 is relatively low, and the coolant at a relatively low temperature can effectively help cool the region closer to the right side of the battery 200. Similarly, the temperature of the coolant in the left region of the battery 200 is relatively high, which is unfavorable for heat dissipation in the left region of the battery 200. However, the temperature of the immersion fluid in the left region of the battery 200 is relatively low, and the relatively low temperature of the immersion fluid can effectively help cool the left region of the battery 200. Therefore, this reverse flow policy achieves temperature complementarity between the immersion fluid and the coolant during the heat dissipation process of the battery 200, optimizing the overall thermal management effect of the battery pack 10.

[0030] It should be explained that in this embodiment, the flow direction of the coolant in the liquid cooling plate 300 and the immersion liquid in the housing 100 refers to the overall flow tendency or direction, and does not restrict the specific flow paths of the coolant in the liquid cooling plate 300 and the immersion liquid in the housing 100.

[0031] In some embodiments, the flow path of the immersion liquid within the housing 100 is changed by adjusting the position of the first liquid inlet 130 on the first end plate 111 and the position of the first liquid outlet 140 on the second end plate 121, thereby optimizing thermal management performance.

[0032] For example, the first liquid inlet 130 is located on the side of the first end plate 111 closer to the liquid cooling plate 300, and the first liquid outlet 140 is located on the side of the second end plate 121 further away from the liquid cooling plate 300. For instance, by designing the liquid cooling plate 300 to be adjacent to the bottom plate of the housing 100, and the first liquid outlet 140 and the first liquid inlet 130 to have a height difference, there is more time and space for the immersion liquid to exchange heat with the surface of the battery 200 before it flows out of the housing 100, allowing the immersion liquid to make more sufficient contact with the surface of the battery 200, resulting in a better heat dissipation effect and more uniform heat dissipation.

[0033] In another example, for instance, the liquid cooling plate 300 is also adjacent to the bottom plate of the housing 100, the first liquid inlet 130 is located on the side of the first end plate 111 away from the liquid cooling plate 300, and the first liquid outlet 140 is located on the side of the second end plate 121 closer to the liquid cooling plate 300. The height of the first liquid inlet 130 may be higher than that of the first liquid outlet 140, as can be understood, the immersion liquid enters from a relatively high liquid inlet and can naturally flow downwards during the flow process, increasing the turbulence of the immersion liquid and improving the contact area between the immersion liquid and the surface of the battery 200 and the heat exchange efficiency.

[0034] In another example, along the width direction of the housing 100, the first liquid inlet 130 is located in the center of the first end plate 111, the first liquid outlet 140 is located in the center of the second end plate 121, and / or along the width direction of the liquid cooling plate 300, the second liquid outlet 340 is located in the center of the third end plate 311, and the second liquid inlet 330 is located in the center of the fourth end plate 321. Here, along the width direction of the housing 100, the immersion liquid enters from the center of the first end plate 111 and flows out to the center of the second end plate 121, and as the immersion liquid flows, it comes into uniform contact with different areas of the surface of the battery 200, enabling more uniform heat dissipation. Similarly, along the width direction of the liquid cooling plate 300, the coolant enters from the center of the fourth end plate 321 and flows out to the center of the third end plate 311, allowing the coolant to make more uniform contact with different areas of the liquid cooling plate 300 during its flow, thereby ensuring that the battery 200 dissipates the heat transferred to the liquid cooling plate 300 uniformly and effectively, effectively avoiding localized hot spots appearing on the surface of the battery 200 and improving the uniformity of heat dissipation.

[0035] Referring to Figures 5, 6, and 7, Figure 5 is a schematic diagram of the third type of structure of a battery pack according to an embodiment of the present application. Figure 6 is a schematic diagram of the battery pack shown in Figure 5 from a different angle. Figure 7 is a cross-sectional view of the battery pack shown in Figure 6 along AA. In some embodiments, the battery pack 10 includes a plurality of housings 100 and a plurality of liquid cooling plates 300, the plurality of housings 100 and the plurality of liquid cooling plates 300 being arranged in a staggered manner and aligned along the thickness direction perpendicular to the liquid cooling plates 300. In this embodiment, the battery pack 10 consists of a plurality of housings 100 and a plurality of liquid cooling plates 300, with one liquid cooling plate 300 installed between two adjacent housings 100 and one housing 100 installed between two adjacent liquid cooling plates 300 along the thickness direction of the liquid cooling plates 300 or the thickness direction of the housings 100. For example, the liquid cooling plate 300 may be located on the bottom plate of the housing 100. Since multiple housings 100 and multiple liquid cooling plates 300 are installed in a staggered manner, the liquid cooling plate 300 is not adjacent to the top plate of the topmost housing 100, but only to the bottom plate, and liquid cooling plates 300 are installed on both the top and bottom sides of each of the other housings 100. In another example, one additional liquid cooling plate 300 may be installed on the top plate of the topmost housing 100 so that liquid cooling plates 300 are installed on both the top and bottom sides of each housing 100. Therefore, the heat generated by the battery 200 can be absorbed and removed from different directions by the coolant in the liquid cooling plates 300 on both the top and bottom sides and the immersion liquid in the housing 100, effectively improving heat dissipation efficiency. Furthermore, the fourth end 320 of the liquid cooling plates 300 on both the upper and lower sides of each housing 100, where the second liquid inlet 330 of the coolant is located, is adjacent to the second end 120 where the first liquid outlet 140 of the immersion liquid is located, and the third end 310 where the second liquid outlet 340 of the coolant is located is adjacent to the first end 110 where the first liquid inlet 130 of the immersion liquid is located. As a result, the coolant in the liquid cooling plates 300 on both the upper and lower sides of each housing 100 can flow in the opposite direction to the immersion liquid. The coolant in the liquid cooling plates 300 on both the upper and lower sides and the immersion liquid in the housing 100 form different temperature gradients relative to the battery 200. In different regions of the battery 200, the cooling medium, which is always at a relatively lower temperature, absorbs heat, reduces the temperature difference on the surface of the battery 200, and improves the overall heat dissipation effect of the battery pack 10.Furthermore, by staggering the placement of multiple housings 100 and multiple liquid cooling plates 300, the battery pack 10 can be easily expanded and modularized, making it easy to adapt to battery packs 10 of different sizes and needs.

[0036] It should be noted that in some embodiments, the liquid cooling plate 300 may be located on the top plate of the housing 100, and this embodiment is not limited to this.

[0037] In some embodiments, the liquid cooling plate 300 includes a covering plate 350 adjacent to the housing 100, and the covering plate 350 further covers the sealed housing space. In this embodiment, the covering plate 350 itself, as part of the liquid cooling plate 300, performs the function of the sealed housing 100, so there is no need to install additional sealing members in the housing 100, and the liquid cooling plate 300 and the housing 100 can share the structure of the covering plate 350, and such an integrated design can reduce the use of housing 100 material. Exemplarily, small holes may be provided in the covering plate 350 so that immersion liquid and coolant at different temperatures can be mixed to some extent, thereby enabling more uniform heat dissipation.

[0038] To understand this, if the battery pack 10 includes only one housing 100 and one liquid cooling plate 300, the installation of one sealing member for the housing 100 can be saved. If the battery pack 10 includes multiple housings 100 and multiple liquid cooling plates 300, the multiple housings 100 and multiple liquid cooling plates 300 can be installed in a staggered manner, and the covering plates 350 of the liquid cooling plates 300 on both the upper and lower sides of each housing 100 can be positioned to seal both the upper and lower sides of the housing 100, thus saving the installation of even more sealing members. For example, if the battery pack 10 includes four housings 100 and four liquid cooling plates 300, the installation of seven sealing members can be saved.

[0039] Therefore, in this embodiment, the design that integrates the sealing functions of the liquid cooling plate 300 and the housing 100 reduces the use of materials, simplifies the overall structure of the battery pack 10, reduces the overall weight of the battery pack 10, improves the volumetric energy density of the battery pack 10, and further simplifies the manufacturing and assembly process, thereby reducing the overall cost.

[0040] Referring to Figures 8, 9, 10, and 11, Figure 8 is a schematic diagram of the fourth type of structure of a battery pack according to an embodiment of the present application. Figure 9 is a schematic diagram of the battery pack shown in Figure 8 from a different angle. Figure 10 is a schematic diagram of the battery pack shown in Figure 8 from yet another angle. Figure 10 is a cross-sectional view of the battery pack shown in Figure 9 along BB. In some embodiments, the battery pack 10 includes a plurality of housings 100 and a plurality of liquid cooling plates 300, wherein the plurality of housings 100 are sequentially adjacent along the longitudinal direction of the housings 100, and the plurality of housings 100 and the plurality of liquid cooling plates 300 are staggered along the height direction of the housings 100.

[0041] The battery pack 10 includes multiple battery units, each of which may include one housing 100 and one liquid cooling plate 300 stacked in the same manner. In addition to the arrangement of multiple battery units in height, the battery pack 10 may also have multiple battery units installed adjacent to each other horizontally, thereby increasing the scale of the battery pack 10. Thus, in this embodiment, the battery pack 10 has a high degree of modularity and expandability, and can be adapted to multiple different application scenarios. Whether it is an electric vehicle, an energy storage system, or other equipment requiring high energy density and efficient heat dissipation, the scale of the battery pack 10 can be adjusted to meet the demand.

[0042] In some embodiments, one chamber is installed inside each housing 100, and along the longitudinal direction of the housing 100, two adjacent housings 100 share one separator plate 150 to separate the two chambers.

[0043] In this embodiment, two adjacent housings 100 can share one separator plate 150, further reducing the structural materials of the battery pack 10. For example, each row of the battery pack 10 includes three housings 100, and the middle housing 100 shares one separator plate 150 with the left-side housing 100 and the right-side housing 100, saving the production of two separator plates 150, further reducing the weight of the battery pack 10, and making the overall array of the battery pack 10 more compact.

[0044] In some embodiments, along the longitudinal direction of the liquid cooling plate 300, the flow direction of the coolant within adjacent liquid cooling plates 300 is the same, and the flow direction of the immersion liquid within adjacent housings 100 is the same.

[0045] To understand this, along the longitudinal direction of the housing 100, after the immersion liquid absorbs the heat from the battery 200, its temperature gradually rises in the direction of flow of the immersion liquid. When it is close to an adjacent housing 100, the temperature of the immersion liquid is relatively high, which is unfavorable for heat dissipation of the battery 200 in that area. When the immersion liquid of an adjacent housing 100 is in the initial stage of flow, there are no heat sources flowing or relatively few heat sources flowing, and its temperature is relatively low. The immersion liquid with a relatively low temperature can effectively help dissipate the heat in that area. Therefore, along the longitudinal direction of multiple housings 100, the immersion liquids of two adjacent housings 100 form a temperature difference near the connection area of ​​the two housings 100, which can complementarily cool the battery 200 and allow the entire battery pack 10 to dissipate heat more uniformly.

[0046] For example, when the liquid cooling plate 300 is adjacent to the bottom plate of the housing 100, in this embodiment, the battery pack 10 has liquid cooling plates 300 installed on both the top and bottom sides of the other housings 100, except for the bottom plate of the first row of housings 100, and housings 100 are installed on both the left and right sides of each housing 100 in addition to the first row of housings 100. Here, on both the top and bottom sides of the housing 100, the flow direction of the coolant in the liquid cooling plate 300 is opposite to the flow direction of the immersion liquid in the housing 100, and on both the left and right sides of the housing 100, the flow direction of the immersion liquid in adjacent housings 100 is the same as the flow direction of the immersion liquid in the housing 100. As a result, the cooling medium at a relatively low temperature always absorbs heat in different areas on the top, bottom, left and right of the battery 200 in the opposing housings 100, reducing the temperature difference on the surface of the battery 200 and improving the overall heat dissipation effect of the battery pack 10.

[0047] In some embodiments, along the thickness direction of the housing 100, the housing 100 includes a first side plate 160 that is close to or away from the liquid cooling plate 300, wherein a first liquid inlet 130 is provided on the first side plate 160 at the portion located at the first end 110, and a second liquid inlet 330 is provided on the first side plate 160 at the portion located at the second end 120, and along the longitudinal direction of the liquid cooling plate 300, the third end 310 includes a third end plate 311, and the fourth end 320 includes a fourth end plate 321, wherein the third end plate 311 and the fourth end plate 321 are installed facing each other, a second liquid outlet 340 is provided on the third end plate 311, and a second liquid inlet 330 is provided on the fourth end plate 321.

[0048] Here, the first side plate 160 may be the top or bottom plate of the housing 100. For example, if the first side plate 160 is the top plate of the housing 100, the first liquid inlet 130 is located at the first end 110 of the first side plate, and the first liquid outlet 140 is located at the second end 120 of the first side plate. Thus, the first liquid inlet 130 and the first liquid outlet are spaced apart at both ends of the first side plate. To make it clear, in this embodiment, the battery pack 10 has multiple housings 100 adjacent to each other horizontally, and the housings 100 and liquid cooling plates 300 are staggered in the height direction. Therefore, the first liquid inlet 130 and the second liquid inlet 330 of the housing 100 are spaced apart on the top plate of the housing 100, allowing the housings 100 in each row to be closely arranged horizontally, and reducing wasted space due to the inappropriate positioning of the first liquid inlet 130 and the first liquid outlet 140.

[0049] It should be noted that the first side plate may also be the bottom plate of the housing 100, and this embodiment is not limited to this.

[0050] In some embodiments, the liquid cooling plates 300 are spaced apart and have a gap between them along the longitudinal direction of the liquid cooling plates 300, and at least some of the first liquid inlets 130, first liquid outlets 140, second liquid inlets 330 and second liquid outlets 340 are exposed to the gap.

[0051] The liquid cooling plates 300 and the housing 100 are installed in a staggered arrangement in terms of height, and multiple liquid cooling plates 300 are installed at intervals in the horizontal direction. This ensures sufficient space for the installation of the first liquid inlet 130, the first liquid outlet 140, the second liquid inlet 330, and the second liquid outlet 340, and ensures smooth flow of the immersion liquid and cooling liquid in the battery pack 10. The first liquid inlet 130, the first liquid outlet 140, the second liquid inlet 330, and the second liquid outlet 340 are installed within the space between them, and inspection and maintenance of their joints are also easy.

[0052] In some embodiments, the first liquid inlets 130 of multiple housings 100 are in communication with each other, and / or the second liquid inlets 330 of multiple liquid cooling plates 300 are in communication with each other.

[0053] For example, by branching one main pipe to each first liquid inlet 130 and / or branching one main pipe to each second liquid inlet 330, it is possible to ensure that all housings 100 receive a uniform supply of immersion liquid, or that all liquid cooling plates 300 receive a uniform supply of coolant. The design of the interconnected first liquid inlets 130 or second liquid inlets 330 significantly simplifies the piping layout and reduces the complexity and length of the piping. This not only reduces the manufacturing cost and maintenance difficulty of the battery pack 10, but also improves the overall aesthetics and space utilization of the battery pack 10.

[0054] Embodiments of the present invention further provide a battery system including a control assembly and a battery pack 10 of any of the above embodiments. The control assembly includes a Battery Management System (BMS), a Battery Disconnect Unit (BDU), etc. The Battery Management System primarily aims to smartly manage and maintain each battery unit 300, monitor the battery status, prevent overcharging and over-discharging of the batteries, and extend the battery life. The Battery Management System further controls the flow of immersion fluid and coolant. Specifically, the Battery Management System can control the flow rate of the immersion fluid based on the temperature of the immersion fluid, and the Battery Management System can control the flow rate of the coolant based on the temperature of the coolant. The main function of the Battery Disconnect Unit is to drive the vehicle by controlling the motor speed and torque with a controller after receiving electrical energy from the charging system, and the Battery Drive Unit further needs to monitor the battery status in real time to ensure the safe operation of the battery. The battery pack 10 employs a combination of indirect liquid cooling and immersion cooling, fully utilizing the advantages of both cooling technologies. Furthermore, by aligning the second end 120, where the first liquid outlet 140 is located, with the fourth end 320, where the second liquid inlet 330 is located, with the second end 320, where the second liquid inlet 330 is located, the cooling medium, which is always at a relatively low temperature in different areas of the battery 200, absorbs heat, reduces the temperature difference on the surface of the battery 200, improves the overall heat dissipation effect of the battery pack 10, and better meets the heat dissipation needs of the battery system in high-power, high-density operation. In addition, multiple housings 100 and multiple liquid cooling plates 300 may be staggered in the vertical direction as needed, and may be further expanded horizontally, increasing the number of housings 100 and liquid cooling plates 300 combinations and increasing the scale of the battery pack 10. Whether it is an electric vehicle, an energy storage system, or other equipment requiring high energy density and efficient heat dissipation, the demand can be met by adjusting the scale of the battery pack 10.

[0055] In this embodiment, the air circulation path is described as being along the long side of the housing, but it may not be localized along the long side of the housing, but rather along the short side. The feature of this embodiment is that by completing the heat exchange between the hot air and the liquid cooling plate, continuous heat exchange between the cool air and the heated battery is achieved.

Claims

1. The interior includes a housing space arranged to contain the immersion liquid, and the housing includes a first end where a first liquid inlet is installed and a second end where a first liquid outlet is installed, which are installed opposite each other. A battery installed in the aforementioned storage space, Adjacent to the aforementioned housing, the interior is arranged to contain a coolant, and the liquid cooling plate includes a third end where a second liquid outlet is installed and a fourth end where a second liquid inlet is installed, which are installed opposite each other. Herein, the first end is adjacent to the third end, and the second end is adjacent to the fourth end, in a battery pack.

2. The battery pack according to claim 1, wherein the distance between the first liquid inlet and the second liquid outlet is L1, and 1 cm ≤ L1 ≤ 10 cm.

3. The battery pack according to claim 1, wherein the distance between the first liquid outlet and the side of the housing away from the liquid cooling plate is L2, and 15 cm ≤ L2 ≤ 22 cm.

4. The battery pack according to claim 1, wherein the distance between the second liquid inlet and the side of the liquid cooling plate closest to the housing is L3, and the distance between the second liquid outlet and the side of the liquid cooling plate closest to the housing is L4, where L4 ≤ L3 and 2 cm ≤ L4 ≤ 6 cm.

5. The battery pack according to claim 1, wherein the height of the housing is H1, the height of the liquid cooling plate is H2, and 2 ≤ H1 / H2 ≤ 5.

6. The battery pack according to claim 1, wherein the length of the housing is D1, the length of the liquid cooling plate is D2, and 15 cm ≤ D1 - D2 ≤ 22 cm.

7. Along the longitudinal direction of the housing, the first end includes a first end plate, the second end includes a second end plate, the first end plate and the second end plate are installed facing each other, the first liquid inlet is installed on the first end plate, and the first liquid outlet is installed on the second end plate. The battery pack according to claim 1, wherein, along the longitudinal direction of the liquid cooling plate, the third end includes a third end plate, the fourth end includes a fourth end plate, the third end plate and the fourth end plate are installed facing each other, the second liquid outlet is installed on the third end plate, the second liquid inlet is installed on the fourth end plate, the third end plate and the first end plate are located on the same side, and the second end plate and the fourth end plate are located on the same side.

8. The battery pack according to any one of claims 1 to 7, wherein the flow direction of the cooling liquid in the liquid cooling plate is opposite to the flow direction of the immersion liquid in the housing.

9. The battery pack according to claim 1, wherein the battery pack includes a plurality of housings and a plurality of liquid cooling plates, the plurality of housings and the plurality of liquid cooling plates are arranged in a staggered manner and are arranged along the thickness direction perpendicular to the liquid cooling plates.

10. The battery pack according to claim 1, wherein the liquid cooling plate includes a covering plate adjacent to the housing, and the covering plate further covers and seals the housing space.

11. The battery pack according to claim 9, wherein a plurality of the housings are sequentially adjacent to each other along the longitudinal direction of the housing.

12. Along the longitudinal direction of the housing, the flow direction of the immersion liquid in adjacent housings is the same. The battery pack according to claim 11, wherein the flow direction of the coolant in adjacent liquid cooling plates is the same along the longitudinal direction of the liquid cooling plates.

13. The battery pack according to claim 11, wherein one chamber is installed in each of the housings, and two adjacent housings share one separator plate along the longitudinal direction of the housings to separate the two chambers.

14. Along the thickness direction of the housing, the housing includes a first side plate that is close to or away from the liquid cooling plate, the first liquid inlet is provided in the portion of the first side plate located at the first end, and the second liquid inlet is provided in the portion of the first side plate located at the second end. The battery pack according to any one of claims 11 to 13, wherein, along the longitudinal direction of the liquid cooling plate, the third end includes a third end plate, the fourth end includes a fourth end plate, the third end plate and the fourth end plate are installed facing each other, a second liquid outlet is installed on the third end plate, and a second liquid inlet is installed on the fourth end plate.

15. The battery pack according to claim 14, wherein the liquid cooling plates are installed at intervals between adjacent liquid cooling plates along the longitudinal direction of the liquid cooling plates, and there is a gap between them, and at least some of the first liquid inlet, first liquid outlet, second liquid inlet and second liquid outlet are exposed to the gap between them.

16. The first liquid inlets of the multiple housings are in communication with each other, and / or The battery pack according to claim 14, wherein the second liquid inlets of a plurality of liquid cooling plates are in communication with one another.

17. A battery system comprising a control assembly and a battery pack according to any one of claims 1 to 16, wherein the control assembly is connected to the battery pack.

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