Immersed battery pack and energy storage system

Abstract

The utility model provides an immersed battery pack and an energy storage system. The immersed battery pack includes: an upper cover; the first box body is provided with a first cavity, the upper cover and the first box body are assembled to cover and seal the first cavity, and the sealed first cavity is filled with insulating heat conduction liquid; the at least one battery cell module and the slave control board electrically connected with the battery cell module are both immersed in the insulating heat-conducting liquid, and gaps among battery cells of the battery cell module are filled with the insulating heat-conducting liquid; the second box body is provided with a second cavity, the second box body is assembled on one side, opposite to the battery cell module, of the upper cover, and the upper cover covers and seals the second cavity; and the electrical element is arranged in the sealed second chamber and is electrically connected with the slave control board. According to the battery pack, relatively small temperature difference between the battery cells can be kept, rapid cooling of the battery pack is facilitated, the energy density of the battery pack is improved, use of an anti-immersion type special plug connector is avoided, and the cost is saved.

Description

Technical Field

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

[0002] The battery pack will generate heat during operation, so heat dissipation is required to ensure its safe charging and discharging. At present, immersion cooling is one of the main ways to dissipate heat. The immersion cooling method is to immerse the battery module in the box and seal it with the upper cover to ensure that the coolant will not leak, and install inlets and outlets on the side of the battery pack to allow the coolant to flow in and out. The coolant in the battery pack is circulated and dissipated through a water pump, pipelines and radiators, so as to achieve the purpose of cooling the battery module. Due to the small gap between the batteries in the battery module, the flow distribution of the coolant in the battery pack is uneven, and the thermal conductivity of the battery itself is low, which ultimately leads to poor cooling effect and excessive temperature difference between the batteries. In addition, the BDU (Battery energy Distribution Unit) and other electrical components of the battery pack are also usually immersed in the coolant of the box, which not only requires a special connector to electrically connect the electrical components to the battery module, but also the electrical components occupy the internal space of the box, which will reduce the energy density of the entire battery pack. Utility Model Content

[0003] In view of this, the present application provides an immersion-type battery pack and energy storage system, which can improve the problem of excessive temperature difference between battery cells, and can also facilitate rapid cooling of the battery pack and improve the energy density of the battery pack, while avoiding the use of special anti-immersion connectors.

[0004] The present application provides an immersion battery pack, comprising:

[0005] Upper cover;

[0006] A first box body is provided with a first chamber, the upper cover is assembled with the first box body to cover and seal the first chamber, and the sealed first chamber is filled with an insulating thermal conductive liquid;

[0007] At least one battery cell module and a slave control board electrically connected to the battery cell module are both arranged in the sealed first chamber and immersed in the insulating thermal conductive liquid, and the insulating thermal conductive liquid fills the gaps between the battery cells of the battery cell module;

[0008] A second box body is provided with a second chamber, the second box body is assembled on a side of the upper cover facing away from the battery module, and the upper cover covers and seals the second chamber;

[0009] The electrical element is arranged in the sealed second chamber and is electrically connected to the slave control board.

[0010] Optionally, the second chamber is filled with air or an inert gas.

[0011] Optionally, the insulating heat-conducting liquid fills up the sealed first chamber so that the insulating heat-conducting liquid flows statically.

[0012] Optionally, the first box body includes a plurality of side beams and a plurality of partitions, the plurality of side beams are arranged to surround and form the first chamber, and the plurality of partitions are arranged in the first chamber and divide the first chamber into a plurality of receiving areas; the immersion battery pack includes a plurality of the battery cell modules, each of the battery cell modules is received in a corresponding receiving area and immersed in the insulating thermal conductive liquid filled in the receiving area.

[0013] Optionally, the insulating heat-conducting liquid includes silicone oil.

[0014] Optionally, the second box is disposed adjacent to one side end of the first box.

[0015] Optionally, the upper cover is integrated with a first liquid cooling plate, and the insulating heat-conducting liquid is in thermal contact with the first liquid cooling plate.

[0016] Optionally, a heat insulating member is provided on a side of the upper cover facing the second box body or on a side facing the battery cell module, and along a direction perpendicular to the upper cover, an orthographic projection of the second box body falls within the orthographic projection of the heat insulating member.

[0017] Optionally, the submerged battery pack further includes: a second liquid cooling plate, disposed at the bottom of the first box body and at least correspondingly disposed below the first chamber, so that the insulating thermally conductive liquid is in thermal contact with the second liquid cooling plate.

[0018] The present application provides an energy storage system, comprising the submerged battery pack as described above.

[0019] Optionally, the energy storage system further includes a cooling source, which is connected to the first liquid cooling plate and the second liquid cooling plate to provide cooling liquid.

[0020] As described above, the present application assembles the upper cover with the first box body to cover and seal the first chamber, and assembles the upper cover with the second box body to cover and seal the second chamber, and arranges the battery cell module in the sealed first chamber and immerses it in the insulating thermal conductive liquid. The insulating thermal conductive liquid fills the gaps between the battery cells of the battery cell module, and the heat generated by each battery cell is absorbed by the insulating thermal conductive liquid, thereby achieving cooling of the battery pack and its battery cells, which is beneficial to the rapid cooling of the battery pack. During the heat dissipation process, the insulating thermal conductive liquid is filled in the sealed first chamber, and has low fluidity or even no flow, so the flow in the battery pack can be avoided. The dynamic distribution is uneven, and the heat exchange between each battery cell and the insulating thermal liquid is not much different, which is beneficial to ensure a small temperature difference between the battery cells; the present application arranges the electrical components in the sealed second chamber, which is equivalent to dividing the entire battery pack into two upper and lower sealed spaces, and the electrical components and battery cell modules are arranged in the upper and lower sealed spaces, so that the electrical components are not immersed in the insulating thermal liquid. Therefore, the use of anti-immersion special connectors can be avoided to electrically connect the electrical components to the battery cell modules, saving costs, and the electrical components do not occupy the space where the battery cell modules are located, which is beneficial to improving the energy density of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of an exploded structure of an immersion battery pack provided in an embodiment of the present application;

[0022] Figure 2 yes Figure 1 A structural side view of the immersed battery pack shown;

[0023] Figure 3 It is a partial structural schematic diagram of a battery cell module provided in an embodiment of the present application;

[0024] Figure 4 is a structural schematic diagram of a first box provided in an embodiment of the present application;

[0025] Figure 5 yes Figure 4 An xy cross-sectional schematic diagram of the first box is shown. DETAILED DESCRIPTION

[0026] In order to solve the above problems existing in the prior art, the present application provides an immersion battery pack and energy storage system. The two protection themes are based on the same concept, and the principles of solving the problems are basically the same or similar. The implementation methods of each protection theme can refer to each other, and the repeated parts will not be repeated.

[0027] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly described below in conjunction with specific embodiments and corresponding drawings. Obviously, the embodiments described below are only part of the embodiments of the present application, not all of the embodiments. In the absence of conflict, the following embodiments and their technical features can be combined with each other and also belong to the technical solutions of the present application.

[0028] In the description of the embodiments of the present application, terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", and "counterclockwise" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the technical solutions of the corresponding embodiments, rather than indicating or implying that a device or element must have a specific orientation, be constructed and operated in a specific orientation, and should not be understood as a limitation on the present application.

[0029] To facilitate the description and understanding of the solution of the present application, the length direction of the battery pack is referred to as the first direction x, the thickness direction is referred to as the second direction y, and the width direction is referred to as the third direction z. The first direction x, the second direction y and the third direction z are perpendicular to each other and can be regarded as the three coordinate axes of a three-dimensional rectangular coordinate system. It should be understood that the so-called perpendicularity in the entire application does not require that the angle between the two must be 90°, but allows a deviation of ±10°, that is, the so-called perpendicularity can be understood as the angle between any two directions is 80° to 100°. Similarly, the so-called parallelism in the entire application does not require that the angle between the two must be 0° or 180°, but allows a deviation of ±10°, that is, the so-called parallelism can be understood as the angle between any two directions is 0° to 10° or 170° to 190°.

[0030] Please also read Figures 1 to 5 As shown, an immersion battery pack (hereinafter referred to as a battery pack in some places) provided in an embodiment of the present application includes an upper cover 1, a first box body 2, at least one battery cell module 3, a slave control board 4, a second box body 5 and electrical components (not shown in the figure).

[0031] The battery cell module 3 includes a plurality of battery cells 30, which are arranged in an array with gaps between adjacent battery cells. Specifically, at least two rows of battery cells 30 are arranged along the third direction z, and multiple rows of battery cells 30 are arranged along the first direction x. The number of battery cells 30 in each row and each row is not limited in this application. It should be understood that Figure 3 The cell module 3 and the arrangement of the cell 30 of the structure shown are only exemplary. The cell module 3 may also include other structural elements, which are not limited here.

[0032] The first box body 2 is provided with a first chamber with an upper opening, and the upper cover 1 is assembled with the first box body 2 to cover and seal the first chamber, and the sealed first chamber is filled with an insulating thermal conductive liquid (not shown). Optionally, the insulating thermal conductive liquid includes silicone oil, which has good insulation and thermal conductivity, so it can avoid short circuits in the battery pack and form good heat exchange with the battery cell 30.

[0033] The first box body 2 may be a welded structure. In one example, the first box body 2 includes a plurality of side beams 21 and a plurality of partitions 22. The plurality of side beams 21 surround and form a first chamber. The plurality of partitions 22 are disposed in the first chamber and divide the first chamber into a plurality of receiving areas Z. For example, see Figure 4 The first box body 2 includes four side beams 21 and three partitions 22. The four side beams 21 can be aluminum alloy components, which are connected end to end by welding to form a first rectangular chamber as a whole; one of the partitions 22 is longer, extends along the first direction x, and its two ends are respectively welded to the two side beams 21, and the other two partitions 22 are shorter and equal in length and are arranged along the third direction z. The two ends of the shorter partition 22 are respectively welded to the longer partition 22 and the corresponding side beam 21, and the two ends of the other shorter partition 22 are respectively welded to the longer partition 22 and the corresponding side beam 21; here, the four side beams 21 and the three partitions 22 divide the first chamber into four receiving areas Z.

[0034] The upper cover 1 can be detachably mounted on the first box body 2. For example, the upper cover 1 can be fixed to the side beams 21 of the first box body 2 by screwing, so as to cover and seal each receiving area Z of the first chamber.

[0035] Each battery cell module 3 is disposed in a receiving area Z corresponding to the sealed first chamber, and is immersed in the insulating thermally conductive liquid filled in the corresponding receiving area Z, and the insulating thermally conductive liquid fills the gaps between the battery cells 30 of the battery cell module 3 .

[0036] Optionally, the insulating thermally conductive liquid fills the sealed first chamber, and of course also fills each sealed receiving area Z, so that the insulating thermally conductive liquid flows statically in the first chamber and its receiving areas Z, thereby making the heat exchange between each battery cell 30 and the insulating thermally conductive liquid almost equal.

[0037] The second box 5 is provided with a second chamber, for example Figure 1 In the placement shown, the second box 5 is provided with a second chamber opening downward. The second box 5 is assembled on a side (eg, upper side) of the upper cover 1 facing away from the battery module 3, and the upper cover 1 covers and seals the second chamber.

[0038] The electrical component is disposed in the sealed second chamber and is electrically connected to the slave control board 4. The electrical component may be a BDU, and the slave control board 4 may be integrated with a BMS (Battery Management System), and the two cooperate to control the charging and discharging of the entire battery pack.

[0039] The sealed second chamber is not filled with insulating heat-conducting liquid, but can be optionally filled with air, which is low in cost. Of course, it can also be filled with non-combustible gas such as inert gas to avoid combustion.

[0040] As described above, the present application assembles the upper cover 1 with the first box body 2 to cover and seal the first chamber, and assembles the upper cover 1 with the second box body 5 to cover and seal the second chamber, and arranges the battery module 3 in the sealed first chamber and immerses it in the insulating thermal conductive liquid. The insulating thermal conductive liquid is filled in the gaps between the battery cells 30 of the battery module 3, and the heat generated by each battery cell 30 is absorbed by the insulating thermal conductive liquid, thereby achieving cooling of the battery pack and its battery cells 30, which is beneficial to the rapid cooling of the battery pack; during the heat dissipation process, the insulating thermal conductive liquid is filled in the sealed first chamber, and has low fluidity or even no flow, so it can be avoided in the battery pack. The flow distribution is uneven, and the heat exchange between each battery cell 30 and the insulating thermal liquid is not much different, which is beneficial to ensure that there is a small temperature difference between the battery cells 30; the present application arranges the electrical components in the sealed second chamber, which is equivalent to dividing the entire battery pack into two upper and lower sealed spaces, and the electrical components and the battery cell module 3 are arranged in the upper and lower sealed spaces, so that the electrical components are not immersed in the insulating thermal liquid. Therefore, the use of anti-immersion special connectors can be avoided to electrically connect the electrical components to the battery cell module 3, saving costs, and the electrical components do not occupy the space where the battery cell module 3 is located, which is beneficial to improve the energy density of the battery pack.

[0041] In one example, the upper cover 1 is integrated with a first liquid cooling plate (not shown), and the insulating heat-conducting liquid is in thermal contact with the first liquid cooling plate. The first liquid cooling plate is provided with an inlet for allowing the coolant (e.g., ethylene glycol aqueous solution) to flow in, an outlet for allowing the coolant to flow out, and a flow channel connected to the inlet and the outlet. The inlet and the outlet may be located on opposite sides of the first housing 2. The coolant enters the first liquid cooling plate from the inlet and flows along the flow channel. During the flow, the heat generated by each battery cell 30 is absorbed by the insulating heat-conducting liquid, and the heat is transferred to the first liquid cooling plate. Finally, the heat is taken away from the battery pack by the first liquid cooling plate, thereby achieving cooling of the battery pack and its battery cells 30, which is beneficial to the rapid cooling of the battery pack. Convection is formed in the first liquid cooling plate, and the coolant with increased temperature finally flows out from the outlet.

[0042] Optionally, a heat insulating member is provided on the side of the upper cover 1 facing the second box body 5 or the side facing the battery cell module 3, and along the direction perpendicular to the upper cover 1 (i.e., the second direction y), the orthographic projection of the second box body 5 falls within the orthographic projection of the heat insulating member, thereby preventing the heat absorbed by the insulating heat-conducting liquid from being transmitted to the electrical components located in the second box body 5 through the first liquid cooling plate, thereby preventing the electrical components from overheating.

[0043] In one example, see Figure 1 and Figure 4 , the submerged battery pack also includes a second liquid cooling plate 6. The second liquid cooling plate 6 is arranged at the bottom of the first box body 2, and is at least correspondingly arranged below the first chamber, so that the insulating thermal conductive liquid is in thermal contact with the second liquid cooling plate 6. For example, the second liquid cooling plate 6 can be a whole structure, which is installed as a whole at the bottom of the first box body 2; for another example, the battery pack is provided with a plurality of second liquid cooling plates 6, and these second liquid cooling plates 6 are respectively installed below the corresponding receiving areas Z, or these second liquid cooling plates 6 are spliced ​​to form a whole structure to be installed at the bottom of the first box body 2, and each second liquid cooling plate 6 can independently perform heat exchange with the insulating thermal conductive liquid.

[0044] Combined Figure 1 , Figure 2 and Figure 5 As shown, the second liquid cooling plate 6 is provided with an inlet 60 for allowing the coolant to flow in, an outlet 61 for allowing the coolant to flow out, and a flow channel connected with the inlet 60 and the outlet 61. The inlet 60 and the outlet 61 are located on opposite sides of the first box body 2. The coolant enters the second liquid cooling plate 6 from the inlet 60 and flows along the flow channel. During the flow, the coolant exchanges heat with the insulating heat-conducting liquid and absorbs the heat of the insulating heat-conducting liquid, thereby forming convection in the second liquid cooling plate 6. Finally, the coolant with increased temperature flows out from the outlet 61.

[0045] Optionally, the width (length along the third direction z) of the flow channel is 45 mm, and the height (length along the second direction y) H is 5 mm to 8 mm.

[0046] As described above, the heat generated by each battery cell 30 is absorbed by the insulating heat-conducting liquid and transferred to the second liquid cooling plate 6. At the lower part of the battery pack, the heat is finally taken away from the battery pack by the second liquid cooling plate 6, thereby achieving cooling of the battery pack and its battery cells 30, which is beneficial to rapid cooling of the battery pack.

[0047] Optionally, a heat-insulating layer and a protective plate are further provided at the bottom of the first box body 2 (neither of which are shown in the figures).

[0048] The heat-insulating layer is disposed between the protective plate and the second liquid cooling plate 6. The heat-insulating layer can prevent the influence of the external temperature on the temperature difference of the battery module 3, and can achieve a smaller temperature difference at a lower cost.

[0049] The protective plate is arranged below the second liquid cooling plate 6 and can be detachably mounted on the corresponding beam 21 and / or the partition 22. The battery pack of the present application can facilitate the disassembly and maintenance of the insulation layer, the protective plate and other components through the detachable installation of the protective plate and the first box body 2, and the protective plate is arranged at the bottom of the battery cell module 3, which can reduce the risk of damage to the battery pack due to collision with the vehicle chassis and other reasons.

[0050] In one example, the second liquid cooling plate 6 is flush with the bottom of the first box 2, or the second liquid cooling plate 6 completely covers the bottom of the first box 2, so that the bottom of the first box 2 can be relatively flat and has a wider range of applications. For example, when the battery pack is installed in a vehicle, the relatively flat bottom can better adapt to the installation environment of the vehicle chassis. For another example, in a scenario where the battery pack is provided with an insulation layer and a protective plate, the insulation layer and the protective plate can be easily installed.

[0051] The embodiment of the present application also provides an energy storage system, including an immersion battery pack as described in any of the above items, so that the beneficial effects of the immersion battery pack of the corresponding embodiment can be produced, which will not be repeated here. The energy storage system may also include a cooling source, which is connected to at least the first liquid cooling plate and / or the second liquid cooling plate 6 of the immersion battery pack to provide cooling liquid to the corresponding liquid cooling plate.

[0052] It should be understood that the submerged battery pack and energy storage system provided in the embodiments of the present application are complete devices respectively, and also have the corresponding structures of known devices, which will not be described one by one here.

[0053] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. For ordinary technicians in this field, all equivalent structural changes made using the contents of this specification and drawings are also included in the patent protection scope of the present application.

[0054] Although the terms "first, second", etc. are used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. In addition, the singular forms "one", "an", and "the" are intended to include plural forms as well. The terms "or" and "and / or" are interpreted as inclusive, or mean any one or any combination. Only when the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way, an exception to this definition will occur.

Claims

1. An immersion battery pack, characterized in that: include: Upper cover; A first box body is provided with a first chamber, the upper cover is assembled with the first box body to cover and seal the first chamber, and the sealed first chamber is filled with an insulating thermal conductive liquid; At least one battery cell module and a slave control board electrically connected to the battery cell module are both arranged in the sealed first chamber and immersed in the insulating thermal conductive liquid, and the insulating thermal conductive liquid fills the gaps between the battery cells of the battery cell module; A second box body is provided with a second chamber, the second box body is assembled on a side of the upper cover facing away from the battery module, and the upper cover covers and seals the second chamber; The electrical element is arranged in the sealed second chamber and is electrically connected to the slave control board.

2. The submerged battery pack according to claim 1, characterized in that: The second chamber is filled with air or an inert gas.

3. The submerged battery pack according to claim 1 or 2, characterized in that: The insulating heat-conducting liquid fills up the sealed first chamber so that the insulating heat-conducting liquid flows statically.

4. The submerged battery pack according to claim 3, characterized in that: The first box body includes a plurality of side beams and a plurality of partitions, the plurality of side beams are arranged to surround and form the first chamber, and a plurality of partitions are arranged in the first chamber and divide the first chamber into a plurality of receiving areas; The submerged battery pack includes a plurality of the battery cell modules, each of which is received in a corresponding receiving area and immersed in an insulating thermally conductive liquid filled in the receiving area.

5. The submerged battery pack according to claim 3, characterized in that: The insulating heat-conducting liquid includes silicone oil.

6. The submerged battery pack according to claim 1, characterized in that: The second box is disposed adjacent to one end portion of the first box.

7. The submerged battery pack according to claim 1, characterized in that: The upper cover is integrated with a first liquid cooling plate, and the insulating heat-conducting liquid is in heat-conducting contact with the first liquid cooling plate.

8. The submerged battery pack according to claim 7, characterized in that: The upper cover is provided with a heat insulating member on one side facing the second box body or on the side facing the battery module, and is provided with a heat insulating member along a direction perpendicular to In the direction of the upper cover, the orthographic projection of the second box falls within the orthographic projection of the thermal insulation component.

9. The submerged battery pack according to claim 1, characterized in that: The submerged battery pack further includes: a second liquid cooling plate, which is disposed at the bottom of the first box body and at least corresponds to the bottom of the first chamber, so that the insulating heat-conducting liquid is in thermal contact with the second liquid cooling plate.

10. An energy storage system, characterized in that: Comprising an immersed battery pack as claimed in any one of claims 1 to 9.

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