Multi-sided cooling liquid-cooling system and power battery pack

Abstract

Disclosed in the present invention are a multi-sided cooling liquid-cooling system and a power battery pack. The power battery pack comprises a first-layer module, a second-layer module and a third-layer module distributed in three layers from bottom to top. The multi-sided cooling liquid-cooling system comprises: a first liquid cooling plate arranged on the bottom surface of the first-layer module, a second liquid cooling plate arranged between the top surface of the first-layer module and the bottom surface of the second-layer module, two third liquid cooling plates arranged between two sides of the top surface of the second-layer module and the bottom surface of the third-layer module, a fourth liquid cooling plate arranged in the middle of the top surface of the second-layer module, and two fifth liquid cooling plates arranged on two sides of the top surface of the third-layer module, wherein liquid inlets of the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plates, the fourth liquid cooling plate, and the fifth liquid cooling plates are in communication with liquid inlet piping, and liquid outlets are in communication with liquid outlet piping; the first liquid cooling plate, the fourth liquid cooling plate, and the fifth liquid cooling plates are stamped cold plates, and the second liquid cooling plate and the third liquid cooling plates are profiled cold plates.

Description

Multi-face cooling liquid cooling system and power battery pack TECHNICAL FIELD

[0001] The present application belongs to the field of engineering machinery, and relates to a multi-face cooling liquid cooling system and a power battery pack, in particular to a multi-face cooling liquid cooling system and a power battery pack for engineering machinery. BACKGROUND

[0002] The multi-layer module large-capacity power battery pack composed of blade cells in engineering machinery has large capacity and requires high-rate charging and discharging, and it is difficult to ensure uniform temperature, and in addition, the working environment of engineering machinery is harsh, and the structural strength requirement is high.

[0003] At present, the research and development of battery packs mainly focuses on passenger cars, and for commercial vehicles and engineering machinery vehicles used in harsh conditions, the uniformity and structural strength of the battery pack designed by using the research and development of passenger car battery packs are difficult to meet. SUMMARY

[0004] Object: In view of at least one of the above technical problems, the present application provides a multi-face cooling liquid cooling system and a power battery pack, which realizes the uniformity of the multi-layer module of the power battery pack of engineering machinery through the multi-face cooling liquid cooling system, and improves the overall stability of the power battery pack of engineering machinery.

[0005] Technical scheme: To solve the above technical problems, the technical scheme adopted by the present application is:

[0006] According to the first aspect of the present application, a multi-face cooling liquid cooling system is provided for cooling or heating the power battery pack of engineering machinery, the power battery pack comprising a first layer module, a second layer module and a third layer module distributed in three layers from bottom to top, the multi-face cooling liquid cooling system comprising: a first liquid cooling plate arranged on the bottom surface of the first layer module, a second liquid cooling plate arranged between the top surface of the first layer module and the bottom surface of the second layer module, two third liquid cooling plates arranged between the top surface of the second layer module and the bottom surface of the third layer module on both sides, a fourth liquid cooling plate arranged in the middle of the top surface of the second layer module, and two fifth liquid cooling plates arranged on both sides of the top surface of the third layer module;

[0007] The liquid inlet of the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate is respectively connected with the liquid inlet pipeline, and the liquid outlet of the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate is respectively connected with the liquid outlet pipeline;

[0008] Among them, the first liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate adopt stamping cold plate, and the second liquid cooling plate and the third liquid cooling plate adopt profile cold plate.

[0009] In some embodiments, the multi-face cooling liquid cooling system further comprises a tray connecting the first liquid cooling plate and the second liquid cooling plate, the tray comprising a tray end plate connected to the end of the first liquid cooling plate and the second liquid cooling plate, forming a first layer module accommodating cavity.

[0010] In some embodiments, the tray further comprises a tray cross beam connected between the first liquid cooling plate and the second liquid cooling plate, the tray cross beam being arranged along the width direction of the first liquid cooling plate and separating the first layer module accommodating cavity into multiple areas.

[0011] In some embodiments, the tray cross beam is two, and the two tray cross beams separate the first layer module accommodating cavity into three areas; the first layer module comprises a first battery module, a second battery module and a third battery module arranged side by side; the first battery module, the second battery module and the third battery module are distributed in the three areas of the first layer module accommodating cavity.

[0012] In some embodiments, the second liquid cooling plate and the third liquid cooling plate are connected by an end plate; the fourth liquid cooling plate and the second liquid cooling plate are connected by an end plate.

[0013] In some embodiments, the lower part of the end plate at the corresponding position on both sides of the second liquid cooling plate is connected to the upper part of the tray end plate.

[0014] In some embodiments, a limiting boss is arranged at the position of the end plate connection in the middle area of the top of the second liquid cooling plate, and the corresponding lower part of the end plate is provided with a boss structure matched with the limiting boss, and the lower part of the end plate is connected with the limiting boss of the second liquid cooling plate through the boss structure.

[0015] In some embodiments, the third liquid cooling plate and the fifth liquid cooling plate are connected by an end plate.

[0016] In some embodiments, the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate are all provided with symmetrical two-side-in and middle-out single-loop flow channels inside in the direction perpendicular to the large surface of the battery module cell.

[0017] In some embodiments, the liquid inlet pipeline is arranged upwards along the first side of the first liquid cooling plate, the second liquid cooling plate, the corresponding third liquid cooling plate and the corresponding fifth liquid cooling plate in sequence, and the liquid outlet pipeline is arranged downwards along the second side of the fifth liquid cooling plate, the third liquid cooling plate, the second liquid cooling plate and the first liquid cooling plate in sequence.

[0018] According to the second aspect of the present application, a power battery pack is provided, comprising the multi-face cooling liquid cooling system.

[0019] Beneficial effects: The multi-face cooling liquid cooling system and power battery pack provided by the application have the following advantages: the series-parallel connection mode of the pipelines between the multi-layer module large-capacity power battery pack cold plates composed of the blade battery cells in the engineering machinery improves the integration degree in the battery pack, realizes the parallel connection of the cold plates, effectively reduces the temperature difference of the battery cells and the modules at different positions, improves the temperature consistency of the battery cells, improves the temperature balance of the large-capacity battery pack, and increases the service life of the battery pack; the stamping plate and the profiled plate are combined to meet the structural strength of the battery pack while realizing weight reduction. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 is a schematic diagram of the overall structure of the power battery pack according to the embodiment of the application;

[0021] Fig. 2 is a schematic diagram of the pipeline design and liquid cooling plate arrangement according to the embodiment of the application;

[0022] Fig. 3 is a schematic diagram of the structure of the liquid cooling plate arrangement according to the embodiment of the application;

[0023] Fig. 4 is a schematic diagram of the liquid cooling plate connection structure according to the embodiment of the application;

[0024] Fig. 5 is a schematic diagram of the vertical section of the liquid cooling plate connection according to the embodiment of the application;

[0025] Fig. 6 is a schematic diagram of the horizontal section of the liquid cooling plate connection according to the embodiment of the application. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments of the application. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the application of the application or use. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0027] The relative arrangement of parts and steps, numerical expressions, and numerical values set forth in the Examples are not intended to limit the scope of the application unless otherwise specifically stated. Also, it is to be understood that the dimensions of the various parts shown in the drawings are not drawn to scale. Techniques, methods, and apparatus known to those of ordinary skill are not discussed in detail because they would be apparent in light of the teachings herein. In all examples shown and discussed herein, any specific values should be interpreted as merely illustrative and not as a limitation. Thus, other examples of exemplary embodiments can have different values. It should be noted that like reference numerals and letters refer to like items in the several views of the drawings, and, as such, further discussion of such items is not required in the subsequent drawings.

[0028] In the description of the application, it needs to be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are used only to explain the relative position relationship, movement condition and the like between the components in a certain posture, and if the certain posture changes, the directional indication also changes accordingly. It is only for the convenience of describing the application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0029] In addition, the terms "first", "second", and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" and the like can explicitly or implicitly include one or more features. In the description of the application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0030] In the description of the application, it needs to be understood that unless otherwise specifically stated and limited, the terms "mounting", "connecting", "connection" should be broadly understood, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood through specific circumstances.

[0031] To solve the problem of large temperature difference between cells in the multi-layer module large capacity battery pack composed of blade cells in engineering machinery, and to reduce the performance problems such as reduction of battery service life caused by poor cell consistency, researchers have proposed different solutions.

[0032] However, in the existing solutions to the problem of temperature consistency of the battery cells in the power battery pack, the temperature difference between the battery cells is mainly reduced by changing the structure of the liquid cooling plate or adding a heat spreader to ensure good temperature consistency of the battery cells. However, the following problems still exist:

[0033] (1) The single-sided cooling scheme results in a large temperature difference between the battery cells in the height direction, which is not conducive to ensuring the temperature consistency of the battery cells.

[0034] (2) The method of changing the structure of the liquid cooling plate prolongs the development cycle, and the open mold cooling plate has a limited application range.

[0035] (3) The method of adding a heat spreader prolongs the main heat transfer path and occupies more space in the battery pack, affecting the volume energy density of the whole pack.

[0036] Therefore, the present application provides a multi-face cooling liquid cooling system suitable for a multi-layer module large-capacity power battery pack composed of blade battery cells in engineering machinery, which uses a multi-face cooling (heating) method of parallel connection of cooling plates to improve the heat exchange efficiency of the liquid cooling system; adopts a pipeline series-parallel connection design to realize parallel connection of the cooling plates, height integration of the multi-face liquid cooling system, uniform flow distribution between the multi-layer modules of the power battery pack, and ensures the temperature consistency of the battery cells in the multi-layer modules; and combines stamping cooling plates and profile cooling plates to reduce weight while meeting the structural strength of the battery pack.

[0037] Embodiment 1: As shown in FIGS. 1-5, a multi-face cooling liquid cooling system is used to cool or heat a power battery pack of engineering machinery, the power battery pack includes a first layer module, a second layer module and a third layer module distributed in three layers from bottom to top, and the multi-face cooling liquid cooling system includes: a first liquid cooling plate 205 arranged on the bottom surface of the first layer module, a second liquid cooling plate 204 arranged between the top surface of the first layer module and the bottom surface of the second layer module, two third liquid cooling plates 203 arranged between the top surface of the second layer module and the bottom surface of the third layer module on both sides, a fourth liquid cooling plate 201 arranged in the middle of the top surface of the second layer module, and two fifth liquid cooling plates 202 arranged on both sides of the top surface of the third layer module;

[0038] The liquid inlet of the first liquid cooling plate 205, the second liquid cooling plate 204, the third liquid cooling plate 203, the fourth liquid cooling plate 201 and the fifth liquid cooling plate 202 is connected with the liquid inlet pipeline, and the liquid outlet of the first liquid cooling plate 205, the second liquid cooling plate 204, the third liquid cooling plate 203, the fourth liquid cooling plate 201 and the fifth liquid cooling plate 202 is connected with the liquid outlet pipeline;

[0039] The first liquid cooling plate 205, the fourth liquid cooling plate 201 and the fifth liquid cooling plate 202 are stamping cooling plates, and the second liquid cooling plate 204 and the third liquid cooling plate 203 are profile cooling plates.

[0040] In some embodiments, as shown in FIG. 1, FIG. 4, FIG. 5, the multi-surface cooling liquid cooling system further comprises a tray 500 connecting the first liquid cooling plate 205 and the second liquid cooling plate 204, the tray 500 comprising a tray end plate connected to the end of the first liquid cooling plate 205 and the second liquid cooling plate 204, forming a first layer module accommodating cavity.

[0041] In some embodiments, the tray 500 further comprises a tray crossbeam connected between the first liquid cooling plate 205 and the second liquid cooling plate 204, the tray crossbeam being arranged along the width direction of the first liquid cooling plate 205 and separating the first layer module accommodating cavity into multiple areas.

[0042] In this embodiment, as shown in FIG. 5, FIG. 6, there are two tray crossbeams 502, 503, which separate the first layer module accommodating cavity into three areas; the first layer module comprises a first battery module, a second battery module and a third battery module arranged side by side; the first battery module, the second battery module and the third battery module are distributed in the three areas of the first layer module accommodating cavity.

[0043] In some embodiments, as shown in FIG. 1, FIG. 4, FIG. 5, the second liquid cooling plate 204 and the third liquid cooling plate 203 are connected by an end plate 401; the fourth liquid cooling plate 201 and the second liquid cooling plate 204 are connected by an end plate 401; the third liquid cooling plate 203 and the fifth liquid cooling plate 202 are connected by an end plate 401.

[0044] Further, in some embodiments, as shown in FIG. 5, the lower part of the end plate at the corresponding position on both sides of the second liquid cooling plate 204 is connected to the upper part of the tray end plate.

[0045] In some embodiments, as shown in FIG. 5, a limiting boss is arranged at the position where the end plate 401 is connected in the middle area of the top of the second liquid cooling plate 204, and the lower part of the corresponding end plate 401 is provided with a boss structure matched with the limiting boss, and the lower part of the end plate 401 is connected with the limiting boss of the second liquid cooling plate 204 through the boss structure.

[0046] In some embodiments, the first liquid cooling plate 205, the second liquid cooling plate 204, the third liquid cooling plate 203, the fourth liquid cooling plate 201 and the fifth liquid cooling plate 202 are all internally provided with symmetrical two-side-in and middle-out single-loop flow channels perpendicular to the direction of the large surface of the battery module cell.

[0047] In some embodiments, the liquid inlet pipeline is arranged upwards along the first side of the first liquid cooling plate 205, the second liquid cooling plate 204, the corresponding third liquid cooling plate 203 and the corresponding fifth liquid cooling plate 202 in turn, and the liquid outlet pipeline is arranged downwards along the second side of the fifth liquid cooling plate 202, the third liquid cooling plate 203, the second liquid cooling plate 204 and the first liquid cooling plate 205 in turn.

[0048] Embodiment 2: A power battery pack comprising the multi-surface cooling liquid cooling system described above.

[0049] In some embodiments, as shown in FIG. 1, the first layer module includes the first battery module, the second battery module and the third battery module arranged side by side; the second layer module includes the fourth battery module, the fifth battery module and the sixth battery module arranged side by side, and the third layer module includes the seventh battery module and the eighth battery module arranged side by side on both sides.

[0050] Correspondingly, the multi-surface cooling liquid cooling system forms a module accommodating cavity corresponding to eight battery modules; so that the upper and lower surfaces of each battery module are attached with liquid cooling plates, realizing multi-surface cooling or heating of each battery module.

[0051] In some embodiments, as shown in FIG. 1, the power battery pack further includes a bottom guard plate 601 and a box cover 101, the bottom guard plate 601 is arranged at the bottom of the tray 500, and the box cover 101 is matched with the top of the multi-surface cooling liquid cooling system and can be arranged on the top of the multi-surface cooling liquid cooling system, for realizing the protection of the entire power battery pack.

[0052] Secondly, the liquid cooling system 200 is fixedly connected with the tray 500 and the end plate 401, which not only meets the structural strength of the battery pack, but also realizes weight reduction.

[0053] In addition, the multi-surface cooling liquid cooling system of the present application is highly integrated: in order to reduce the number and space occupancy of joints and pipelines, the pipelines are designed in series and parallel, realizing parallel connection between the cooling pipelines of seven liquid cooling plates to facilitate the distribution of system flow; in order to ensure the consistency of the temperature of the multi-layer module battery cells composed of blade cells, each liquid cooling subsystem is designed in a single loop flow channel with two sides in and one side out in the direction perpendicular to the large surface of the cells, avoiding excessive heating at the tab of the blade cell and leading to uneven distribution of cell temperature, wherein the liquid cooling subsystem corresponding to the first liquid cooling plate 205 at the bottom is designed in a zoned flow channel (as shown in FIG. 6) in combination with the distribution of the module, which not only ensures the consistency of the temperature of the cells, but also reduces the flow resistance of the liquid cooling system.

[0054] In order to ensure the structural strength of the multi-layer module large-capacity battery pack composed of blade battery cells, a design scheme combining stamping cold plates and profile cold plates is adopted (as shown in FIG. 4). ① The bottom and top of the battery pack are non-bearing areas, and stamping cold plates (the first liquid cold plate 205, the fourth liquid cold plate 201, and the fifth liquid cold plate 202) are used to be fixed with the tray 500 and the end plate 401. Bottom: the first liquid cold plate 205 is welded with the tray 500, the bottom layer module in the module 700 is supported by the tray 500, and the first liquid cold plate 205 only plays a liquid cooling role; top: the fourth liquid cold plate 201, the fifth liquid cold plate 202, and the end plate 401 are fixed; ② The middle layer module of the battery pack needs to support the module while being liquid-cooled, so the profile cold plate (the second liquid cold plate 204 and the third liquid cold plate 203) with good bearing performance is used for liquid cooling, the bottom of the second liquid cold plate 204 is fixed with the tray end plate 501 and 504 in the tray 500, and is glued with the tray beam 502 and 503 (to avoid passing through the flow channel), the middle area of the top of the second liquid cold plate 204 is welded with the boss of the end plate 401 (to avoid passing through the flow channel), and the third liquid cold plate 203 is fixed with the end plate 401 (as shown in FIG. 5).

[0055] In summary, the multi-face cooling liquid cooling system and the power battery pack provided by the application improve the integration degree in the battery pack by the series-parallel connection mode of the pipelines between the cold plates of the multi-layer module large-capacity power battery pack composed of blade battery cells in the engineering machinery, realize the parallel connection of the cold plates, effectively reduce the temperature difference of the battery cells and modules at different positions, improve the temperature consistency of the battery cells, improve the temperature balance of the large-capacity battery pack, and increase the service life of the battery pack.

[0056] The technical means disclosed in the application scheme is not limited to the technical means disclosed in the above embodiments, and also includes technical solutions composed of any combination of the above technical features. The above has disclosed the application with preferred embodiments, but it is not intended to limit the application, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the application.

Claims

1. A multi-sided cooling liquid cooling system for cooling or heating a power battery pack of a working machine, characterized in that, The power battery pack comprises a first layer module, a second layer module and a third layer module distributed in three layers from bottom to top, and the multi-face cooling liquid cooling system comprises: a first liquid cooling plate arranged on the bottom surface of the first layer module, a second liquid cooling plate arranged between the top surface of the first layer module and the bottom surface of the second layer module, two third liquid cooling plates arranged between the top surface of the second layer module and the bottom surface of the third layer module, a fourth liquid cooling plate arranged in the middle of the top surface of the second layer module, and two fifth liquid cooling plates arranged on both sides of the top surface of the third layer module; Liquid inlets of the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate are respectively connected with liquid inlet pipelines, and liquid outlets of the first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate are respectively connected with liquid outlet pipelines. The first liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate adopt stamping cold plates, and the second liquid cooling plate and the third liquid cooling plate adopt profile cold plates.

2. The multi-sided liquid cooling system of claim 1, wherein, The multi-face cooling liquid cooling system further comprises a tray connecting the first liquid cooling plate and the second liquid cooling plate, and the tray comprises a tray end plate connected to the end portions of the first liquid cooling plate and the second liquid cooling plate, forming a first layer module accommodating cavity.

3. The multi-sided liquid cooling system of claim 2, wherein, The tray further comprises a tray cross beam connected between the first liquid cooling plate and the second liquid cooling plate, which is arranged along the width direction of the first liquid cooling plate and separates the first layer module accommodating cavity into multiple areas.

4. The multi-sided liquid cooling system of claim 3, wherein, The tray cross beam is two, and the two tray cross beams separate the first layer module accommodating cavity into three areas; the first layer module comprises a first battery module, a second battery module and a third battery module arranged side by side; and the first battery module, the second battery module and the third battery module are correspondingly distributed in the three areas of the first layer module accommodating cavity.

5. The multi-sided liquid cooling system of claim 2, wherein, The second liquid cooling plate and the third liquid cooling plate are connected through end plates; and the fourth liquid cooling plate and the second liquid cooling plate are connected through end plates.

6. The multi-sided liquid cooling system of claim 5, wherein, The lower part of the end plate at the corresponding position on both sides of the second liquid cooling plate is connected with the upper part of the tray end plate.

7. The multi-sided liquid cooling system of claim 5, wherein, A limiting boss is arranged at the position where the end plate of the middle area of the top of the second liquid cooling plate is connected, and the corresponding lower part of the end plate is provided with a boss structure matched with the limiting boss, and the lower part of the end plate is connected with the limiting boss of the second liquid cooling plate through the boss structure.

8. The multi-sided liquid cooling system of claim 1, wherein, The third liquid cooling plate and the fifth liquid cooling plate are connected through end plates.

9. The multi-sided liquid cooling system of any of claims 1-8, wherein, The first liquid cooling plate, the second liquid cooling plate, the third liquid cooling plate, the fourth liquid cooling plate and the fifth liquid cooling plate are all provided with symmetrical two-side inlet and middle outlet single-loop flow channels inside in the direction perpendicular to the large surface of the battery module cell.

10. The multi-sided liquid cooling system of any of claims 1-8, wherein, The liquid inlet pipeline is arranged upwards along the first side of the first liquid cooling plate, the second liquid cooling plate, the corresponding third liquid cooling plate and the corresponding fifth liquid cooling plate in sequence, and the liquid outlet pipeline is arranged downwards along the second side of the fifth liquid cooling plate, the third liquid cooling plate, the second liquid cooling plate and the first liquid cooling plate in sequence.

11. A power battery pack, characterized in that, The multi-face cooling liquid cooling system comprises any one of claims 1 to 10.

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