Aluminum die-casting blank shell for battery pack water-cooling plate based on surface low porosity

Abstract

The invention discloses an aluminum die-casting blank shell for a battery pack water cooling plate based on surface low porosity. The aluminum die-casting blank shell comprises a cooling plate main body located in the middle and structural bodies located at the two ends. The cooling plate main body and the structural body are integrally formed by aluminum die-casting; the first side face of the cooling plate body in the thickness direction is provided with an inwards-concave flow channel groove with an upper opening, and a flow channel partition wall is arranged in the flow channel groove. A water inlet and a water outlet which are communicated with the runner groove are formed in the outer side of the structural body; the second side surface of the thickness of the cooling plate main body is provided with a functional surface; a plurality of crossed grid-shaped bulges formed by grid units are distributed on the whole functional surface; the bottom faces of the grid units of the crossed grid-shaped protrusions are planes, so that the porosity of the whole die casting is reduced, the surface quality is greatly improved after the structures are removed through CNC machining, and the phenomenon that the insulation qualification rate is affected due to the pinhole defect in subsequent insulation treatment is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of a water-cooling plate for a battery pack of a new energy vehicle, and in particular to an aluminum die-casting blank shell for a water-cooling plate of a battery pack which is directly formed by aluminum die-casting without being machined. Background Art

[0002] With the rapid development of the new energy vehicle industry, the performance and safety of battery packs as its core power components have received widespread attention. Battery packs generate a lot of heat during operation. If the heat cannot be effectively dissipated, it may lead to a decline in battery performance, shortened life, and even cause safety issues such as thermal runaway. Therefore, an efficient thermal management system has become one of the indispensable key technologies for new energy vehicle battery packs, and the design and manufacturing process of water cooling plates as the core components of the thermal management system are particularly important. Traditional new energy vehicle battery pack cooling plates are mostly formed by aluminum alloy machining or extrusion molding.

[0003] Patent CN221613985U discloses a cooling device and a battery pack, wherein the cooling device comprises a liquid cooling plate and two connecting pieces, wherein a first layer cooling channel and a second layer cooling channel penetrating along a first direction are provided in the liquid cooling plate. The two connecting pieces are respectively assembled with the two ends of the liquid cooling plate, so that the penetrating liquid cooling plate is encapsulated to form a complete flow channel structure.

[0004] Aluminum die-casting is a precision casting process that quickly fills the mold cavity with molten metal under high pressure and solidifies under pressure. In recent years, with the increasing demand for lightweight and high-performance parts in new energy vehicles, aluminum die-casting technology has been increasingly used in the manufacturing of automotive parts. Aluminum die-casting water-cooling plates have also become a key technology for the evolution of new energy vehicle batteries towards high efficiency, integration, and low cost, and will continue to develop in the direction of ultra-large integrated die-casting in the future.

[0005] The battery pack water-cooling plate includes functional surfaces for placing battery cells. These functional surfaces have strict insulation requirements. Therefore, the aluminum die-cast water-cooling plate needs to be insulated on the surface, generally using processes such as electrophoresis and powder spraying.

[0006] The forming of aluminum die-cast water-cooling plates is generally based on the requirements of customer drawings, and 0.5-1mm machining allowance is uniformly added to the machining surface, and CNC machining is subsequently used to remove it to ensure product size requirements. The main problem is that after removing the dense layer on the surface of the blank, internal pores and other defects are exposed on the surface, which is easy to form pinhole defects during product powder spraying, which has a great impact on the insulation qualification rate of the product after powder spraying. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide an aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity.

[0008] The technical solution of the present invention is: an aluminum die-casting blank shell for a battery pack water-cooling plate with low surface porosity, comprising a cooling plate body in the middle and a structure at both ends; the cooling plate body and the structure are integrally formed by aluminum die-casting; The first side surface of the thickness of the cooling plate body has a concave and upper open flow channel, and the flow channel has a flow partition wall; the outer side of the structure is provided with a water inlet and a water outlet connected to the flow channel; the second side surface of the thickness of the cooling plate body is provided with a functional surface; the entire surface of the functional surface is arranged with a cross-grid-like protrusion composed of multiple grid units; the bottom surface of the grid unit of the cross-grid-like protrusion is a plane.

[0009] A preferred technical solution of the present invention is that an outer edge of the second side surface of the thickness of the cooling plate body is provided with an annular protrusion surrounding the functional surface.

[0010] The preferred technical solution of the present invention is that the cross-grid-shaped protrusions are uniform diamond or square grids.

[0011] The preferred technical solution of the present invention is that the width of the ridges of the cross-grid-shaped protrusions gradually decreases from the root to the end face, and the end face is a plane.

[0012] The preferred technical solution of the present invention is that the edge height of the cross-grid-shaped protrusions is 0.3mm-0.5mm.

[0013] The preferred technical solution of the present invention is that the distribution density of the grid units of the cross-grid-shaped protrusions is 9-12 / cm².

[0014] The preferred technical solution of the present invention is that the edges of the grid-shaped protrusions form an angle of 15°-25° with the bottom surface of the grid unit.

[0015] The technical solution of the present invention is: an aluminum die-cast blank shell for a battery pack water-cooling plate with low surface porosity, including a cooling plate body formed by aluminum die-casting, wherein a water-cooling flow channel is arranged in the cooling plate body; the surface of the cooling plate body includes at least one functional surface; the functional surface is entirely provided with cross-grid-like protrusions.

[0016] The preferred technical solution of the present invention is: comprising a structure located at both ends of the cooling plate body and integrally die-cast with the cooling plate body; The first side surface of the thickness of the cooling plate body has a concave and upwardly open flow channel, and the flow channel has a flow partition wall; the outer side of the structure is provided with a water inlet and a water outlet connected to the flow channel; the second side surface of the thickness of the cooling plate body is provided with the functional surface.

[0017] The preferred technical solution of the present invention is: the ridge width of the cross-grid-shaped protrusions gradually decreases from the root to the end face and the end face is a plane; the ridge height of the cross-grid-shaped protrusions is 0.3mm-0.5mm.

[0018] Compared with the prior art, the advantages of the present invention are: when the aluminum liquid is filled into the product cavity and passes through the intersecting grooves on the mold, the aluminum liquid swirls in the grooves, thereby entrapping impurities on the surface of the aluminum liquid and part of the gas in the cavity in the groove structure, which reduces the hole defect rate and impurity rate of the main body part that needs to be retained later. Not only is the surface quality of the functional surface significantly improved, but also because the die-casting gas has an additional escape channel, the porosity of the entire die-casting is reduced. Therefore, after CNC processing to remove these structures, the surface quality of each surface, especially the second side surface of the bottom shell, is greatly improved, thereby avoiding pinhole defects in the subsequent insulation treatment and affecting the insulation qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments, but those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be used as a limitation on the scope of the present invention. In addition, unless otherwise specified, the drawings are only schematically representing the composition or structure of the described objects and may contain exaggerated displays, and the drawings are not necessarily drawn to scale.

[0020] Figure 1 Schematic diagram of the structure of the aluminum die-casting blank shell for the battery pack water cooling plate based on low surface porosity Figure 1 ; Figure 2 Schematic diagram of the structure of the aluminum die-casting blank shell for the battery pack water cooling plate based on low surface porosity Figure 2 ; Figure 3 A schematic diagram of the cross-grid-shaped raised edges of the aluminum die-cast blank shell for the base battery pack water cooling plate; Figure 4 Schematic diagram of die casting of aluminum die casting blank shell for battery pack water cooling plate based on low surface porosity; Figure 5 Schematic diagram of the structure of the battery pack water cooling plate.

[0021] Figure numerals: blank shell 100; aluminum alloy cover plate 200; cooling plate body 1; structure 2; flow channel groove 3; water inlet 4; water outlet 5; functional surface 6; cross grid-shaped protrusion 7; annular protrusion 8; product cavity 11; groove 12; ridge 71; grid unit bottom surface 72. DETAILED DESCRIPTION

[0022] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It will be appreciated by those skilled in the art that these descriptions are only illustrative and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0023] It should be noted that like reference numerals denote similar items in the following drawings, and thus, once an item is defined in one drawing, it will not be further defined or explained in the subsequent drawings.

[0024] like Figure 1-2 As shown, the aluminum die-casting blank shell 100 for the battery pack water-cooling plate based on low surface porosity is a die-casting directly formed by aluminum die-casting. It is an intermediate process object for preparing the battery pack water-cooling plate, and its size and surface morphology are finally changed by machining.

[0025] like Figure 1 As shown, the aluminum die-casting blank shell 100 for the battery pack water cooling plate based on the low surface porosity includes a cooling plate body 1 in the middle and a structure 2 at both ends. The cooling plate body 1 and the structure 2 are integrally formed by aluminum die-casting. The first side of the thickness of the cooling plate body 1 has a concave and upper open flow channel 3, and the flow channel 3 has a flow channel partition wall. The outer side of the structure 2 is provided with a water inlet 4 and a water outlet 5 connected to the flow channel 3.

[0026] like Figure 2 As shown, the second side surface of the thickness of the cooling plate body 1 is provided with a functional surface 6. This functional surface 6 needs to be coated with an insulating layer after the surface is processed by subsequent machining, so there are relatively strict requirements on the surface flatness, porosity, etc. Aluminum die castings are prone to pore defects during the die casting process, and these pores are usually inside the entity where the exhaust is not smooth. Therefore, after the size is adjusted by machining and the burrs are trimmed to remove the dense layer on the surface of the blank, the internal pores and other defects of the aluminum die casting are easily exposed on the surface, thereby affecting the surface performance of the product.

[0027] like Figure 2-3 As shown, in this embodiment, the functional surface 6 of the blank housing 100 is specially designed so that it can meet the surface performance requirements of subsequent processes after machining. Specifically, by setting cross grooves on the die for die-casting the blank housing 100, a cross-grid-shaped protrusion 7 composed of a plurality of grid units is formed on the functional surface 6 of the blank housing 100, and the bottom surface 72 of the grid unit of the cross-grid-shaped protrusion 7 is a plane.

[0028] like Figure 4As shown in the figure, when the aluminum liquid fills into the product cavity K and passes through the groove M on the mold, the aluminum liquid swirls in the groove, thereby entrapping the impurities on the surface of the aluminum liquid and part of the gas in the cavity in the groove structure. This reduces the hole defect rate and impurity rate of the main body part that needs to be retained later, thereby improving the quality of the internal part of the product.

[0029] For aluminum die-cast products, machining to adjust the size and remove burrs is a relatively common technical means to finish the blank shell 100 to form the final product. In this embodiment, the additional cross-grid-shaped protrusions 7 are removed while adjusting the size and removing the burrs by machining, which can avoid the increase of additional processes and thus ensure production efficiency.

[0030] Due to the design of the cross-grid-shaped protrusions 7, not only the surface quality of the functional surface 6 is significantly improved, but also the porosity of the entire die-casting is reduced because the die-casting gas has an additional escape channel. Therefore, after CNC processing to remove these structures, the surface quality of each surface, especially the second side surface of the bottom shell, is greatly improved, thereby avoiding pinhole defects in the subsequent insulation treatment and affecting the insulation qualification rate.

[0031] The design of the cross-grid-like protrusions 7 has another advantage. Since the aluminum pressing component will face stress during demolding and subsequent processing, the design of the cross-grid-like protrusions can reduce its own demolding deformation by enhancing the structural strength of the blank, and avoid product damage and deformation during subsequent processing, which provides many conveniences for subsequent processes.

[0032] Preferably, the cross-grid-shaped protrusions 7 are uniform rhombus or square grids. The width of the ridges 71 of the cross-grid-shaped protrusions 7 gradually decreases from the root to the end face, and the end face is a plane. This design detail plays a vital role in the smoothness of the die-casting process and the uniformity of the product. The design in which the width of the ridges of the cross-grid-shaped protrusions 7 gradually decreases from the root to the end face makes the outer side of the ridge form a certain inclination angle with the bottom surface of the grid unit. This inclination design corresponds to the design of the mold groove, which can greatly promote the gas to enter the mold groove more smoothly during the die-casting process.

[0033] like Figure 4 As shown in the figure, when the aluminum liquid is filled into the product cavity, it is injected horizontally, and its main filling direction is consistent with the reference plane, while the inclined transitional grid-like protrusions can effectively guide the gas and impurities into its structure, thereby forming more gas escape channels inside the die casting. This design feature not only significantly reduces the porosity of the die casting, but also greatly improves the internal quality of the product.

[0034] At the same time, if Figure 3As shown, the inclined morphology of the ridges 71 of the cross-grid-shaped protrusions 7 can also avoid the influence of the cross-grid-shaped protrusions 7 on the internal stress of the blank shell 100. Preferably, the ridge height of the cross-grid-shaped protrusions 7 is 0.3mm-0.5mm. The grid unit distribution density of the cross-grid-shaped protrusions 7 is 9-12 / cm². The ridges 71 of the cross-grid-shaped protrusions and the bottom surface 72 of the grid unit are at an angle of 15°-25°. The design of these parameters can find a balance between surface performance, mechanical strength, and processing convenience.

[0035] It should be noted that in other embodiments, the surface of the blank shell 100 provided with a water-cooling channel may include more than just one functional surface 6. According to the concept of this embodiment, cross-grid-like protrusions 7 may be provided on the entire surface of each functional surface 6 to meet the performance requirements of the surface after subsequent machining.

[0036] In this embodiment: Figure 5 As shown, the aluminum die-cast blank shell 100 for the battery pack water cooling plate and the aluminum alloy cover plate 200 are welded and packaged by friction welding to form an assembly. The assembly is subsequently machined, and the size is adjusted by excess cutting and the cross-grid-shaped protrusions are removed. At this time, a component with surface performance that meets the requirements can be formed.

[0037] In this embodiment, if Figure 2 As shown, the outer edge of the second side of the thickness of the cooling plate body 1 is provided with an annular protrusion 8 surrounding the functional surface 6. This annular protrusion surrounds the functional area to achieve stable placement of the battery unit.

[0038] The aluminum die-casting blank shell for the battery pack water cooling plate based on low surface porosity provided by the present invention is introduced. The principle and implementation method of the present invention are explained in this article using specific examples. The description of the above embodiments is only used to help understand the present invention and its core ideas. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. Aluminum die-casting blank shell for battery pack water cooling plate based on low surface porosity, characterized by: It includes a cooling plate body in the middle and structures at both ends; the cooling plate body and the structures are integrally formed by aluminum die casting; The first side surface of the thickness of the cooling plate body has a concave and upper open flow channel, and the flow channel has a flow partition wall; the outer side of the structure is provided with a water inlet and a water outlet connected to the flow channel; the second side surface of the thickness of the cooling plate body is provided with a functional surface; the entire surface of the functional surface is arranged with a cross-grid-like protrusion composed of multiple grid units; the bottom surface of the grid unit of the cross-grid-like protrusion is a plane.

2. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1 is characterized in that: An outer edge of the second side surface of the thickness of the cooling plate body is provided with an annular protrusion surrounding the functional surface.

3. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1 is characterized in that: The cross-grid-shaped protrusions are uniform rhombus or square grids.

4. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1, characterized in that: The width of the ridges of the cross-grid-shaped protrusions gradually decreases from the root to the end surface, and the end surface is a plane.

5. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1, characterized in that: The edge height of the cross-grid-shaped protrusions is 0.3mm-0.5mm.

6. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1, characterized in that: The grid unit distribution density of the cross-grid-shaped protrusions is 9-12 / cm².

7. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 1, characterized in that: The edges of the grid-shaped protrusions form an angle of 15°-25° with the bottom surface of the grid unit.

8. Aluminum die-casting blank shell for battery pack water cooling plate based on low surface porosity, characterized in that: It comprises a cooling plate body formed by aluminum die casting, wherein a water cooling channel is arranged inside the cooling plate body; the outer surface of the cooling plate body comprises at least one functional surface; and the entire functional surface is provided with cross-grid-shaped protrusions.

9. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 8, characterized in that: It comprises a structure located at both ends of the cooling plate body and integrally formed by die-casting with the cooling plate body; The first side surface of the thickness of the cooling plate body has a concave and upwardly open flow channel, and the flow channel has a flow partition wall; the outer side of the structure is provided with a water inlet and a water outlet connected to the flow channel; the second side surface of the thickness of the cooling plate body is provided with the functional surface.

10. The aluminum die-casting blank shell for a battery pack water cooling plate based on low surface porosity according to claim 9, characterized in that: The width of the ridges of the cross-grid-shaped protrusions gradually decreases from the root to the end face, and the end face is a plane; the ridge height of the cross-grid-shaped protrusions is 0.3mm-0.5mm.

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