CTB battery box structure
By using the CTB battery box structure, different profile sections, and optimized rolling process, the problems of high production cost and heavy weight of battery boxes have been solved, achieving low-cost production and lightweight design, and improving production efficiency and structural stability.
Patent Information
- Application Number
- CN202422935019.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2034-11-29
AI Technical Summary
Existing battery box structures suffer from the problems of high welding difficulty and cost of aluminum materials, and high density and weight of steel materials, resulting in high production costs, limited production capacity, and difficulty in achieving lightweight design.
By adopting the CTB battery box structure, and by selecting different profile cross sections and material strengths, optimizing the rolling process, and designing components such as side beams, mounting beams, and intermediate beams, low-cost production and lightweighting are achieved.
Shorten the development cycle, improve production efficiency, simplify post-processing, enhance sealing effect, reduce adjustment and processing steps, ensure structural strength and stability, and achieve low-cost production and lightweighting.
Smart Images
Figure CN223638499U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery technology field, especially a CTB battery box structure. BACKGROUND
[0002] The endurance of new energy electric vehicles has been the focus of market attention and has become the bottleneck of the development of electric vehicles today, so the lightweight design of the battery box structure is the focus of the research and development of vehicle enterprises. Aluminum alloy materials have become one of the important materials for lightweight new energy vehicles at the present stage due to their excellent machinability, corrosion resistance and low density, but the welding of aluminum materials is difficult, resulting in high product cost, large production line investment and limited production capacity, while the cost of roll-pressed high-strength steel box body is low and the production capacity is high, becoming a new research hotspot in the battery box industry. However, due to the large density of steel materials, the weight target of the box body is quite different from that of the aluminum box body, so in the design of the steel roll-pressed battery box body, the frame profile structure and material strength need to be considered, and the use of CTB structure battery pack body integration design can achieve the lightweight goal of the battery box design. SUMMARY
[0003] The main purpose of the utility model is to provide a CTB battery box structure, which can shorten the development cycle and improve the production efficiency, and realize low-cost production and lightweight through the selection of different profile sections and material strengths and the optimization of the roll-pressing process.
[0004] To achieve the above purpose, the utility model provides a CTB battery box structure, which comprises:
[0005] The side beams comprise left side beams, right side beams, front side beams and rear side beams, the left side beams and the right side beams are used for supporting and fixing battery units, and the front side beams and the rear side beams are connected with the left side beams and the right side beams respectively to form a rectangular accommodating space.
[0006] The mounting beams are welded to the left side beams and the right side beams respectively and are used for connecting the battery trays and other structural components of the vehicle.
[0007] The intermediate beams comprise cross beams and longitudinal beams, the longitudinal beams are connected with the front side beams and the rear side beams at both ends respectively, the cross beams are connected with the left side beams and the right side beams at both ends respectively, and the cross beams and the longitudinal beams cross to form a grid-shaped structure.
[0008] Optionally, the cross sections of the left side beams and the right side beams are in the shape of a three-cavity "eye" structure, and the material is HC550 / 980DP material with a thickness of 1.2 mm.
[0009] Optionally, the left beam and the right beam are provided with first grooves.
[0010] Optionally, the mounting beam has a cross section in the shape of a "day" pipe, and is made of 1.2mm-thick HC550 / 980DP material.
[0011] Optionally, one side of the mounting beam is deformed and is welded to the left beam and the right beam to connect the battery tray frame, and the other side of the mounting beam is provided with a mounting sleeve in a cavity to be connected to the whole vehicle.
[0012] Optionally, the front beam and the rear beam have a symmetric "B" shaped cross section, and are made of 1.2mm-thick HC420 / 780DP material.
[0013] Optionally, the front beam and the rear beam are provided with second grooves.
[0014] Optionally, the cross beam has a "day" shaped cross section, and is made of 1.2mm-thick HC550 / 980DP material.
[0015] Optionally, the longitudinal beam has a "mouth" shaped cross section, and is made of 1.2mm-thick HC420 / 780DP material.
[0016] Compared with the prior art, the utility model has the beneficial effects as follows:
[0017] 1. By selecting different material cross sections and material strengths and optimizing the rolling process, low-cost production and light weight are achieved.
[0018] 2. The development cycle is shortened and the production efficiency is improved, and the optimized design and process flow help shorten the cycle from design to production; the design optimization of the cross section of each beam helps improve the efficiency of the final assembly.
[0019] 3, The post-processing process is simplified, the groove design of the mounting beam simplifies the flow of the electrophoretic liquid, avoids the electrophoretic white exposure condition, and reduces the coating process in the post-processing; the reverse bending process of the front and rear side beams improves the forming quality and precision of the profile, and reduces the subsequent adjustment process; after the profile contour of the left and right side beams is formed, the profile cross-sectional size precision, straightness and twist degree are adjusted, thereby reducing the subsequent adjustment and processing processes; before the roll forming, a mechanical punch is used to pre-punch holes in the inside of the profile, thereby improving the production efficiency and reducing the processing process after the forming; the profile assembly is spliced and welded to ensure the strength and stability of the overall structure, and to avoid more complex or more welding processes. The pretreatment of the sealing connection process is to increase the width of the sealing surface, and the R angle of the left and right side beams is designed to be convex on the left and right sides, and a groove (glue overflow groove) is added on the right side, which is used for storing glue and increasing the sealing effect when the liquid cooling plate is glued and connected, thereby enhancing the sealing effect and connection stability. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained according to the structures shown in the drawings without creative labor.
[0021] Figure 1 It is a structural schematic view of an embodiment of the CTB battery box structure of the present application.
[0022] Figure 2 It is a sectional view of the left side beam and the right side beam.
[0023] Figure 3 It is a sectional view of the mounting beam.
[0024] Figure 4 It is a sectional view of the front side beam and the rear side beam.
[0025] Figure 5 It is a sectional view of the cross beam.
[0026] Figure 6 It is a sectional view of the longitudinal beam.
[0027] Explanation of reference numerals:
[0028]
[0029] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION
[0030] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by the ordinary skilled in the art without creative labor fall within the scope of protection of the present application.
[0031] It should be noted that all the directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between the components in a certain specific posture (as shown in the drawings), if the specific posture changes, the directionality indications also change accordingly.
[0032] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that the ordinary skilled in the art can realize it, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the scope of protection required by the present application.
[0033] The present application provides a CTB battery box structure 100.
[0034] Please refer to Figure 1 In an embodiment of the present application, the CTB battery box structure 100 comprises a side beam, a mounting beam 50 and an intermediate beam; wherein the side beam comprises a left side beam 10, a right side beam 20, a front side beam 30 and a rear side beam 40, the left side beam 10 and the right side beam 20 are used to support and fix the battery unit, the front side beam 30 and the rear side beam 40 are connected with the left side beam 10 and the right side beam 20 respectively, forming a rectangular accommodating space; the left side beam 10 and the right side beam 20 are respectively welded with the mounting beam 50, which is used to connect the battery tray and other structural components of the vehicle; the intermediate beam comprises a cross beam 60 and a longitudinal beam 70, the longitudinal beam 70 is connected with the front side beam 30 and the rear side beam 40 at both ends respectively, the cross beam 60 is connected with the left side beam 10 and the right side beam 20 at both ends respectively, and the cross beam 60 and the longitudinal beam 70 cross to form a grid structure.
[0035] In the present embodiment, the left side beam 10 and the right side beam 20 as the main stress part of the battery tray frame play the role of supporting and fixing the battery unit, and provide the main protection and structural strength in the collision.
[0036] The mounting beam 50 is welded on the left beam 10 and the right beam 20, and is used for connecting the battery tray and other structural components of the vehicle, ensuring stable installation of the battery assembly and dispersing impact force when the vehicle is subjected to external force.
[0037] The front beam 30 and the rear beam 40 are not the main force receiving parts, and play the roles of auxiliary supporting the battery tray, enhancing the overall structural integrity, and providing mounting fixing points.
[0038] The cross beam 60 is a structural member connecting the left beam 10 and the right beam 20, which helps to enhance the overall stability and load bearing capacity of the battery tray, and together with the longitudinal beam 70 forms a grid structure to improve the rigidity and bending resistance of the battery tray.
[0039] Please refer to Figure 2 In an embodiment of the present application, the cross section of the left beam 10 and the right beam 20 is in the shape of a three-cavity "eye" structure, and the material is HC550 / 980DP material with a thickness of 1.2 mm. The first groove is provided on the left beam 10 and the right beam 20, and is located on the right side of the cross section view (not shown in the figure), which is a glue overflow groove used for storing glue and increasing sealing effect when the liquid cooling plate is connected by glue coating.
[0040] In this embodiment, the left beam 10 and the right beam 20 are the main force receiving parts of the battery tray frame, and the profile cross section itself needs to be complex enough to resist deformation during collision. Considering safety performance, cost and processing technology, the left beam 10 and the right beam 20 finally adopt the three-cavity "eye" structure, and the material is HC550 / 980DP material with a thickness of 1.2 mm. Through box simulation, the strength meets the design target, and the profile height is 25 mm.
[0041] Please refer to Figure 2 again, the profile forming process of the left beam 10 and the right beam 20 can be roughly divided into the following three stages:
[0042] The first stage: the both sides of the plate strip start to be formed, and the right side cavity is closed and welded at position 1 in the middle position; Figure 2
[0043] The second stage: the features of the left and right sides are bent at the same time, and are folded upward to close the cavity, and are welded in turn according to the welding sequence;
[0044] The third stage: at this time, the product outline has been formed, but the profile cross section size precision, straightness, twist degree and the like need to be adjusted to meet the product requirements.
[0045] The left beam and the right beam are roll formed, and then need to be sawed in length, laser cut mounting holes and small assembly welded, and finally integrated in frame welding,
[0046] Please refer to Figure 3 In an embodiment of the present application, the mounting beam 50 has a cross section in the shape of a "day" pipe deformed cross section, and is made of 1.2mm thick HC550 / 980DP material.
[0047] In the embodiment, the mounting beam 50 is a bridge connecting the battery tray frame and the vehicle body, and is welded on the left beam 10 and the right beam 20, so it has higher requirements for function and strength, and is made of 1.2mm thick HC550 / 980DP material, and has a "day" type deformed cross section.
[0048] The deformed side of the mounting beam 50 is welded and fixed with the left beam 10 and the right beam 20, and connects the battery tray frame, and the cavity of the non-deformed side is provided with a mounting sleeve for connecting with the whole vehicle. The right side groove of the mounting beam 50 plays a role of a reinforcing rib to improve the rigidity of the profile, and on the other hand, facilitates the flow of electrophoresis liquid during the later electrophoresis of the frame, so as to avoid the occurrence of electrophoresis white spots, thereby causing the frame corrosion resistance to be unqualified. According to the stress characteristics of the mounting beam 50, the right side R angle is increased, and the main reason is to ensure that the force arm is lengthened after the mounting beam 50 is welded with the left beam 10 and the right beam 20, so that the cross section is designed as an asymmetric structure, and the forming process needs more passes, and is divided into three stages:
[0049] In the first stage, the right side cavity feature is formed through a large number of forming passes, and after the cavity is laser welded and closed,
[0050] In the second stage, the left side cavity is formed and laser welded,
[0051] In the third stage, the profile cross section is slightly adjusted.
[0052] The post-processing process is relatively simple compared with other profiles, mainly according to the product length sawing off line, and then can be integrated in frame welding.
[0053] Please refer to Figure 4 In an embodiment of the present application, the front beam 30 and the rear beam 40 have a symmetric "B" type cross section, and are made of 1.2mm thick HC420 / 780DP material, and the front beam 30 and the rear beam 40 are both provided with a second groove, and the second groove is located on the right side of the cross section (not shown in the figure).
[0054] In this embodiment, the second groove has the same function as the first groove, both of which are glue overflow grooves for storing glue and increasing sealing effect during the glue connection of the liquid cooling plate. Since the front beam 30 and the rear beam 40 are not the main stress parts, the rigidity and strength requirements of the cross section are relatively weak, so the design should focus on lightweight, saving forming passes and reducing production costs. Therefore, the HC420 / 780DP material with a thickness of 1.2 mm is selected, and the cross section adopts a relatively simple and symmetrical "B" type cross section.
[0055] Since the upper and lower sealing surfaces of the box body are fastened by draw core rivets and pull rivet nuts, and the width of the left and right side cavities is small, the front beam 30 and the rear beam 40 have installation holes on the upper and lower sealing surfaces and through holes on the inner side to prevent interference of the fasteners. Before roll forming, a mechanical punch is used to pre-punch the inside of the profile to improve production efficiency. After pre-punching, the left and right sides are simultaneously roll formed.
[0056] Due to the cross-sectional characteristics of the front beam 30 and the rear beam 40, a large number of empty bending situations occur during the forming process, i.e., the roller die cannot be pressed to the bending angle. This situation is not conducive to the accurate control of the forming. Therefore, the front beam 30 and the rear beam 40 adopt a special forming method - reverse bending process. This process maximizes the bending of the bending angle, thereby improving the forming quality and precision of the profile. The forming process of the front beam 30 and the rear beam 40 can be roughly divided into the following three stages:
[0057] Please refer to Figure 4 , the first stage: start forming the left and right side cavities through multiple forming passes, close the right side cavity and weld at positions 1 and 2 in Figure 4 in turn.
[0058] The second stage: the left and right side features are bent at the same time, the cavity is gradually closed, and welding is performed in turn according to the welding sequence in Figure 4 .
[0059] The third stage: the product outline is basically formed, but further adjustments of the profile cross-sectional size precision, straightness and twist degree, etc. are needed to ensure that it meets the design requirements.
[0060] After forming, the front beam and the rear beam also need to be subjected to offline laser cutting and pressure riveting and other post-processing processes. Specifically, they include:
[0061] Offline laser cutting: cutting the product length and further processing of the pre-punched holes.
[0062] Pressure riveting: providing necessary fixing hole positions for subsequent installation.
[0063] Welding: performing the final welding process to ensure the strength and stability of the profile.
[0064] Referring to Figure 5 In an embodiment of the present application, the cross section of the cross beam 60 is in a "day" type structure, and the material is 1.2mm thick HC550 / 980DP material.
[0065] In the embodiment, the cross beam 60 is connected with the left beam 10 and the right beam 20, and is the main stress part in lateral collision. The battery tray cross beam is formed by super high strength steel rolling, which shortens the tooling time compared with the traditional tailor welding process. In order to meet the high strength requirement, the material of the cross beam 60 is selected as 1.2mm thick HC550 / 980DP material, and there are four cross beams in total. The profile cross section design adopts a typical "day" type structure.
[0066] The forming process of the cross beam 60 is similar to that of the mounting beam 50, but the required forming passes are relatively less. The forming process is divided into the following three stages:
[0067] The first stage: forming the left side cavity feature and closing after welding.
[0068] The second stage: forming the right side cavity feature and closing after welding.
[0069] The third stage: performing micro-adjustment of product size to ensure the accuracy and stability of the cross section.
[0070] After forming, the cross beam 60 also needs to undergo a series of post-processing processes to ensure its performance and quality. Specifically, it includes:
[0071] Offline sawing: cutting the product length to ensure dimensional accuracy.
[0072] Laser cutting: further processing mounting hole and details.
[0073] Small assembly tailor welding: tailor welding the profile assembly to ensure the strength and stability of the overall structure.
[0074] Referring to Figure 6 In an embodiment of the present application, the cross section of the cross beam 60 is in a "day" type structure, and the material is 1.2mm thick HC550 / 980DP material.
[0075] In the embodiment, the cross beam 60 is connected with the left beam 10 and the right beam 20, and is the main stress part in lateral collision. The battery tray cross beam is formed by super high strength steel rolling, which shortens the tooling time compared with the traditional tailor welding process. In order to meet the high strength requirement, the material of the cross beam 60 is selected as 1.2mm thick HC550 / 980DP material, and there are four cross beams in total. The profile cross section design adopts a typical "day" type structure.
[0076] The left beam 10 and the right beam 20 are designed to have a roller-pressed section in the shape of a "eye", which serves as a main load-bearing side column impact function, and the "eye" shape is one of the most complex high-strength steel roller-pressed parts, and the structural strength is about 1.8 times that of an ordinary "day" shape, which is a powerful side column impact structure.
[0077] The front beam 30 and the rear beam 40 are integrated with a plurality of mounting hole positions and are not the main force structure, so a "B" shaped roller-pressed section is adopted, which is light in weight, simple in structure, easy to be roller-pressed, and low in cost.
[0078] The cross beam 60 serves to support the left beam 10 and the right beam 20 to strengthen the side column impact, and in order to improve the crashworthiness, the "day" shaped section is more suitable. The longitudinal beam 70 is not the main force position in the side column impact, so the "mouth" shaped section can meet the requirements. The longitudinal beam 70 and the cross beam 60 are spliced by the CMT welding process.
[0079] The mounting beam 50 serves to support the left beam 10 and the right beam 20, and install the mounting sleeve and the vehicle connection. The Z-direction force and the surface contour requirement are high, so the boot-shaped structure is selected as the force structure, and the rest of the small stamping or open roller-pressed parts are made of DP590 material, which reduces the weight, so as to achieve the purpose of light weight.
[0080] The above is only the preferred embodiment of the present application, and does not limit the patent range of the present application. Any equivalent structural transformation, direct / indirect application in other related technical fields under the inventive concept of the present application, or the contents of the present application are included in the patent protection range of the present application.
Claims
1. A CTB battery case structure, characterized by, The utility model relates to a battery frame structure for electric vehicle, comprising: side beams, the side beams include left side beam, right side beam, front side beam and rear side beam, the left side beam and the right side beam are used to support and fix battery unit, the front side beam and the rear side beam are connected with the left side beam and the right side beam respectively, form the rectangular containing space; hanging beam, the left side beam and the right side beam are welded with the hanging beam respectively, for connecting battery tray and other structural components of vehicle; intermediate beam, the intermediate beam includes crossbeam and longitudinal beam, the longitudinal beam both ends are connected with the front side beam and the rear side beam respectively, the crossbeam both ends are connected with the left side beam and the right side beam respectively, the crossbeam and the longitudinal beam cross constitute a grid structure.
2. The CTB battery case structure of claim 1, wherein: The cross section of the left side beam and the right side beam is three cavity "eye” type structure, and the material is 1.2mm thick HC550 / 980DP material.
3. The CTB battery case structure of claim 2, wherein: The left side beam and the right side beam are provided with first grooves.
4. The CTB battery case structure of claim 1, wherein: The cross section of the hanging beam is "day” pipe deformation cross section, and the material is 1.2mm thick HC550 / 980DP material.
5. The CTB battery can structure of claim 4, wherein: The deformed side of the hanging beam is welded with the left side beam and the right side beam and fixed, connects battery tray frame, and the cavity of the non-deformed side is provided with mounting sleeve for connecting with vehicle.
6. The CTB battery can structure of claim 1, wherein: The cross section of the front side beam and the rear side beam is symmetric "B” type cross section, and the material is 1.2mm thick HC420 / 780DP material.
7. The CTB battery can structure of claim 6, wherein: The front side beam and the rear side beam are provided with second grooves.
8. The CTB battery can structure of claim 1, wherein: The cross section of the crossbeam is "day” type structure, and the material is 1.2mm thick HC550 / 980DP material.
9. The CTB battery can structure of claim 1, wherein: The cross section of the longitudinal beam is "mouth” type structure, and the material is 1.2mm thick HC420 / 780DP material.