Battery cover

Abstract

To provide a battery cover that includes a plurality of air passages for a battery and can strengthen the rigidity of a battery pack.SOLUTION: A battery pack 10 includes a first cover member 23, a second cover member 24, and a reinforcement 25. The first cover member 23 covers a battery stack 22 from above. The second cover member 24 is joined to the first cover member 23 from above. The reinforcement 25 extends in the longitudinal direction of the battery stack 22 and is arranged between a first cover member 23 and a second cover member 24. Furthermore, in a gap formed between the first cover member 23, the second cover member 24, and the reinforcement 25, a smoke exhaust air passage 26 and an exhaust air passage 27 are formed.SELECTED DRAWING: Figure 4B

Description

[Technical Field]

[0001] The present invention relates to a battery cover. [Background technology]

[0002] BACKGROUND ART As a conventional battery pack, for example, the structure described in Patent Document 1 is known.

[0003] The battery pack protects a battery pack made up of multiple battery stacks, etc., and includes a battery pack storage container that the battery pack is stored in. The battery pack storage container is made up of a storage container that stores the battery pack, and frames that support the periphery of the storage container.

[0004] The battery pack is housed in a storage container disposed in a storage space provided on the rear floor of the vehicle, and the frames are connected to the vehicle body around the storage space. The roughly box-shaped storage container houses multiple battery stacks. The connection terminals of the battery stacks are connected to electronic devices such as a junction box and a BCU (Battery Control Unit) via electrical wiring.

[0005] Furthermore, the following Patent Documents 2 to 5 describe configurations for cooling a battery stack inside a battery pack. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6688275 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-120690 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-185894 [Patent Document 4] Japanese Patent Application Publication No. 2019-160774 [Patent Document 5] Japanese Patent Application Laid-Open No. 2014-29797 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the inventions described in the above-mentioned patent documents leave room for improvement in terms of cooling efficiency and collision safety.

[0008] Specifically, in the above-mentioned documents, the cooling structure for cooling the battery and the protective structure for protecting the battery from impact during a vehicle collision are provided as separate components. Therefore, providing the cooling structure and the protective structure in the battery pack leads to the battery pack becoming more complex, larger, and more expensive.

[0009] Furthermore, in the battery pack, the air passage through which the air that cooled the battery flows and the air passage through which the gas generated by the battery flows are located in separate locations, which makes the battery pack complicated.

[0010] The present invention has been made in consideration of these problems, and an object of the present invention is to provide a battery cover that has multiple air passages for cooling the battery and can strengthen the rigidity of the battery pack. [Means for solving the problem]

[0011] The present invention is a battery cover that covers a battery stack housed in a battery pack, and includes a first cover member, a second cover member, a reinforcement, a smoke exhaust air passage, and an exhaust air passage, wherein the first cover member covers the battery stack from above, the second cover member is joined to the first cover member from above, the reinforcement extends along the longitudinal direction of the battery stack and is disposed between the first cover member and the second cover member, the smoke exhaust air passage is an air passage through which gas generated from the battery stack is exhausted, and the exhaust air passage is an air passage through which air that has exchanged heat with the battery stack is exhausted, and the smoke exhaust air passage and the exhaust air passage are formed in a gap formed between the first cover member, the second cover member, and the reinforcement. The smoke exhaust air passage is formed between the reinforcement and the second cover member, and the exhaust air passage is formed between the first cover member and the second cover member. It is characterized by the following. The present invention provides a battery cover for covering a battery stack housed in a battery pack, the battery cover comprising a first cover member, a second cover member, a reinforcement, a smoke exhaust air passage, and an exhaust air passage, the first cover member covering the battery stack from above, the second cover member being joined to the first cover member from above, the reinforcement extending along the longitudinal direction of the battery stack and being disposed between the first cover member and the second cover member, the smoke exhaust air passage being an air passage through which gas generated from the battery stack is exhausted, the exhaust air passage being an air passage through which air that has exchanged heat with the battery stack is exhausted, the smoke exhaust air passage and the exhaust air passage being formed in a gap formed between the first cover member, the second cover member, and the reinforcement, The battery pack has a frame arranged outside the battery stack, and an end side of the reinforcement is connected to the frame. [Effects of the Invention]

[0012] According to the battery cover of the embodiment of the present invention, the battery cover itself has high rigidity due to the presence of reinforcement. This increases the rigidity of the entire battery pack and protects the battery stack from collision impacts, etc. Furthermore, by forming a smoke exhaust air passage and an exhaust air passage in the battery cover, there is no need to install separate smoke exhaust ducts or exhaust ducts, simplifying the overall structure of the battery pack. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view showing a rear portion of a vehicle equipped with a battery pack according to an embodiment of the present invention. [Figure 2] 1 is an exploded perspective view showing a battery pack according to an embodiment of the present invention; [Figure 3] FIG. 2 is an exploded perspective view showing the battery cover according to the embodiment of the present invention. [Figure 4A] 1 is a cross-sectional view partially illustrating a battery pack according to an embodiment of the present invention. [Figure 4B] FIG. 2 is a cross-sectional view partially showing the battery cover according to the embodiment of the present invention. [Figure 5] 5A to 5C are cross-sectional views showing a method of manufacturing a battery cover according to an embodiment of the present invention. [Figure 6A] 1 is a top view showing a state in which an impact is applied to the battery pack from the left according to an embodiment of the present invention. FIG. [Figure 6B] 1 is a top view showing a state in which an impact is applied to the battery pack from the right side according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] A battery pack 10 according to an embodiment of the present invention will be described in detail below with reference to the drawings. In the following description, the front, rear, up, down, left, and right directions are used, and the left and right directions refer to the left and right directions when the vehicle 11 is viewed from the rear. Furthermore, in the following description, the same components are generally designated by the same reference numerals, and repeated explanations will be omitted.

[0015] FIG. 1 is a perspective view showing the rear of a vehicle 11 equipped with a battery pack 10. As shown in FIG.

[0016] The vehicle 11 is, for example, an automobile, a train, or the like, and is equipped with a battery pack 10 for supplying power to a motor and electrical components mounted on a vehicle body 12. The vehicle 11 is, for example, an EV (Electrical Vehicle), an HEV (Hybrid Electrical Vehicle), or a PHEV (Plug-in Hybrid Electrical Vehicle). The vehicle 11 is equipped with a battery pack 10 having a high power storage function.

[0017] The battery pack 10 is disposed in a storage space 13 formed below the rear floor.

[0018] FIG. 2 is an exploded perspective view showing the battery pack 10. As shown in FIG.

[0019] The battery pack 10 mainly comprises a battery stack 22, a battery case 21, and a battery cover 20. The battery cover 20 closes the top opening of the battery case 21. Here, the battery cover 20 is shown separated from the upper side of the battery case 21.

[0020] The battery stack 22 is formed by connecting multiple battery cells. The battery cells are, for example, secondary batteries such as nickel-metal hydride batteries or lithium-ion batteries. The battery cells have, for example, a rectangular flat plate shape and are arranged at approximately equal intervals with gaps between them along the longitudinal direction of the battery stack 22, i.e., the left-right direction. Here, two battery stacks 22 are arranged side by side inside the battery case 21. A smoke exhaust passage 38 is disposed above the battery stack 22. The smoke exhaust passage 38 is a substantially duct-shaped member. The smoke exhaust valves of each battery cell constituting the battery stack 22 are connected to the lower surface of the smoke exhaust passage 38. A smoke exhaust opening 31 is formed near the right end of the upper surface of the smoke exhaust passage 38. The smoke exhaust opening 31 is connected to a smoke exhaust port 232 of the battery cover 20, which will be described later. Note that electrical components and the like (not shown here) are disposed on the front side inside the battery case 21.

[0021] The battery case 21 is made of a steel plate, a synthetic resin plate, or the like, and has a generally box-like shape that is open at the top.

[0022] The frame 33 is a rigid member that connects to the upper edge of the battery case 21. The frame 33 is made up of a front frame 34, a rear frame 35, a left frame 37, and a right frame 36. When viewed from above, the frame 33 is a rectangular frame-like member. The frame 33 is made of a steel plate or the like that is bent into a predetermined shape.

[0023] The battery cover 20 is a generally plate-shaped member that covers the battery stack 22 housed in the battery pack 10. The battery cover 20 closes the top opening of the battery case 21. In this manner, the battery stack 22 is housed in a generally sealed space surrounded by the battery case 21 and the battery cover 20. The detailed configuration of the battery cover 20 will be described later with reference to FIG. 3.

[0024] FIG. 3 is an exploded perspective view showing the battery cover 20. As shown in FIG.

[0025] The battery cover 20 includes a first cover member 23, a second cover member 24, a reinforcement 25, a smoke exhaust air duct 26, and an exhaust air duct 27. The smoke exhaust air duct 26 and the exhaust air duct 27 will be described later with reference to Fig. 4A etc. A cover frame 40 is disposed on the upper surface of the first cover member 23.

[0026] The first cover member 23 covers the battery stack 22 from above. The first cover member 23 is made of a steel plate that is approximately rectangular when viewed from above. An exhaust port 231 and a smoke exhaust port 232 are formed in the first cover member 23. The first cover member 23 is also sometimes referred to as a cover battery box or the like.

[0027] The exhaust ports 231 are openings through which air that has exchanged heat with the battery stack 22 described above, for example, air that has cooled the battery stack 22, passes. When viewed from above, the shape of the exhaust ports 231 is, for example, substantially circular. The exhaust ports 231 are formed in rows at substantially equal intervals along the left-right direction, and four rows are formed in the front-rear direction. With reference to FIG. 2, the two rows of exhaust ports 231 arranged at the rear pass through the air that has cooled the battery stack 22 arranged at the rear. With reference to FIG. 2, the two rows of exhaust ports 231 arranged at the front pass through the air that has cooled the battery stack 22 arranged at the front.

[0028] The smoke exhaust port 232 is a generally circular opening on the right end side of the first cover member 23. Two smoke exhaust ports 232 are formed here. Referring to FIG. 2, the smoke exhaust port 232 formed at the rear passes through gas generated from the battery stack 22 arranged at the rear. Referring to FIG. 2, the smoke exhaust port 232 formed at the front passes through gas generated from the battery stack 22 arranged at the front. Here, the gas is generated from the battery stack 22 when, for example, a collision accident occurs.

[0029] The second cover member 24 is a generally plate-shaped member made of a steel plate or the like and joined to the first cover member 23 from above. The second cover member 24 constitutes the upper portion of the battery cover 20. The second cover member 24 is joined to the first cover member 23 by welding, for example. Furthermore, the second cover member 24 has an uneven shape as shown below, which can suppress deformation of the battery cover 20 and the battery pack 10 when an impact is applied from either the left or right direction. The second cover member 24 is also sometimes called a cover battery cross member or the like.

[0030] Specifically, the second cover member 24 has, from the front, a front flat portion 241, a convex portion 242, a central flat portion 243, the convex portion 242, and a rear flat portion 244. The front flat portion 241, the central flat portion 243, and the rear flat portion 244 are portions formed to be substantially flat, and these portions are joined to the first cover member 23 by welding or the like. The convex portion 242 is a portion having a cross-sectional shape that protrudes upward in a substantially hat shape. Referring to FIG. 2, each of the convex portions 242 is disposed above each of the two battery stacks 22.

[0031] The raised portion 245 is a portion that is raised upward from the left-right intermediate portion of the front flat portion 241, the central flat portion 243, and the rear flat portion 244. A cover frame 40, which will be described later, is disposed on the raised portion 245.

[0032] The reinforcement 25 extends along the longitudinal direction of the battery stack 22 shown in FIG. 2 and is disposed between the first cover member 23 and the second cover member 24. The reinforcement 25 is made of a steel plate or the like that is bent into a predetermined shape. Here, two reinforcements 25 are disposed side by side in the front-to-rear direction, and each reinforcement 25 is disposed above the battery stack 22 shown in FIG. 2. The reinforcement 25 has an uneven shape, which can suppress deformation of the battery cover 20 and the battery pack 10 when an impact is applied from either the left or right direction.

[0033] Specifically, the reinforcement 25 is composed of a front flat portion 251, a recessed portion 252, and a rear flat portion 253. The front flat portion 251 and the rear flat portion 253 are portions formed substantially flat and are portions joined to the convex portion 242 of the second cover member 24. The recessed portion 252 is a portion that protrudes downward in a substantially hat shape and is in close contact with the upper surface of the first cover member 23. The smoke exhaust port 255 is a portion that opens in a substantially circular shape near the right end of the recessed portion 252 and overlaps with the smoke exhaust port 232 of the first cover member 23. The recessed portion 252 is an opening through which gas generated from the battery stack 22 described above passes.

[0034] The raised portion 254 is a portion that is raised upward from the middle portion of the recessed portion 252. The cover frame 40, which will be described later, is disposed on the raised portion 254.

[0035] The cover frame 40 is a portion that extends in the front-to-rear direction and has a generally hat-shaped cross section, with its rear portion joined to the upper surface of the first cover member 23. The front end side of the cover frame 40 is joined to the front frame 34 shown in FIG. 2, and the rear end side of the cover frame 40 is joined to the rear frame 35. The cover frame 40 can suppress deformation of the battery cover 20 and the battery pack 10 when an impact is applied from either the front or rear directions.

[0036] 4A is a cross-sectional view partially showing the battery pack 10. FIG. 4B is a cross-sectional view partially showing the battery cover 20.

[0037] 4A, smoke exhaust airflow path 26 and exhaust airflow path 27 are formed in the gap formed between first cover member 23, second cover member 24, and reinforcement 25. Here, smoke exhaust airflow path 26 is an airflow path through which gas 28 generated from battery stack 22 is exhausted, and exhaust airflow path 27 is an airflow path through which air 29 that has exchanged heat with battery stack 22 is exhausted.

[0038] 4B, the bottom surface of the recessed portion 252 of the reinforcement 25 is welded to the upper surface of the first cover member 23. In addition, the front flat portion 251 and the rear flat portion 253 of the reinforcement 25 are welded to the lower surface of the protruding portion 242 of the second cover member 24.

[0039] With this configuration, the smoke exhaust airflow path 26 is formed between the reinforcement 25 and the second cover member 24, and the exhaust airflow path 27 is formed between the first cover member 23 and the second cover member 24. Specifically, the exhaust airflow path 27 is formed as a space surrounded by the first cover member 23, the convex portion 242, and the reinforcement 25. The exhaust airflow path 27 communicates with the internal space of the battery pack 10 via the exhaust port 231. The smoke exhaust airflow path 26 is formed as a space surrounded by the concave portion 252 of the reinforcement 25 and the convex portion 242 of the second cover member 24. The smoke exhaust airflow path 26 communicates with the smoke exhaust opening 31 of the smoke exhaust passage portion 38 shown in FIG. 2 via the smoke exhaust port 232 and the smoke exhaust port 255. Furthermore, with this configuration, the exhaust airflow path 27 and the smoke exhaust airflow path 26 do not communicate with each other inside the battery cover 20. Therefore, gas 28 that has flowed into smoke exhaust airflow duct 26 is prevented from entering exhaust airflow duct 27.

[0040] 4A , while the battery stack 22 is discharging or charging, air 29 is blown into the battery pack 10 by a blower (not shown). For example, air 29 that has been cooled in the passenger compartment of the vehicle 11 is blown into the battery pack 10. The air 29 blown into the battery pack 10 is heated by cooling each battery cell of the battery stack 22, and then flows into the exhaust air duct 27 and is then released to the outside of the battery pack 10.

[0041] On the other hand, when gas 28 is generated from battery stack 22 due to a collision accident or other cause, gas 28 passes through smoke exhaust passage 38 and smoke exhaust opening 31 shown in Fig. 2, and further passes through smoke exhaust outlet 255 and smoke exhaust outlet 232 shown in Fig. 4B, and flows into smoke exhaust duct 26. Thereafter, gas 28 passes through smoke exhaust duct 26 and is released to the outside of battery pack 10.

[0042] FIG. 5 is a cross-sectional view showing a step of joining the second cover member 24 and the reinforcement 25 by spot welding in the manufacturing method of the battery cover 20.

[0043] When manufacturing the battery cover 20, first, the first cover member 23, the reinforcement 25, and the second cover member 24 are arranged so as to be stacked. In this state, the first cover member 23, the second cover member 24, and the reinforcement 25 are joined by spot welding. Here, the parts to be spot-welded are surrounded by dotted lines.

[0044] Here, the exhaust port 231 formed in the first cover member 23 has a shape and size that allows the welding jig 32 to be inserted therethrough. That is, the width of the exhaust port 231 is larger than the width of the jig 32. Therefore, the welding jig 32 can be inserted through the exhaust port 231 of the jig 32, and the upper end of the jig 32 can be brought into contact with the lower surface of the rear flat portion 253. That is, the exhaust port 231 is an air outlet through which air that has cooled the battery stack 22 passes, and is also a work hole that is used during welding.

[0045] At the same time, the jig 32 on the other side is brought into contact with the upper surface of the convex portion 242. Also, the upper surface of the rear flat portion 253 of the reinforcement 25 is brought into close contact with the lower surface of the convex portion 242 of the second cover member 24. By applying a high voltage to the jig 32 in this state, the reinforcement 25 and the second cover member 24 are joined by spot welding.

[0046] FIG. 6A is a top view showing a situation in which an impact is applied to the battery pack 10 from the left.

[0047] As described above, the frame 33 has the left frame 37 and the right frame 36. Here, referring to FIG. 3 , the left and right ends of the first cover member 23 constituting the battery pack 10 are joined to the left frame 37 and the right frame 36, respectively. Also, the left and right ends of the reinforcement 25 are joined to the left frame 37 and the right frame 36, respectively. Furthermore, the left and right ends of the second cover member 24 are joined to the left frame 37 and the right frame 36, respectively. That is, the left and right ends of each member constituting the battery cover 20 are joined to the left frame 37 and the right frame 36.

[0048] 4B, the cross section of the battery cover 20 has a cross-sectional shape in which the first cover member 23, the second cover member 24, and the reinforcement 25 are joined to each other at multiple locations. With this configuration, the rigidity of the battery cover 20 is increased.

[0049] Therefore, when the plunger 30 is thrust against the battery pack 10 from the left side to check the resistance of the battery pack 10 to an impact from the left, the impact is alleviated and absorbed by the components of the battery cover 20. As a result, the battery pack 10 does not deform significantly, and damage to the battery stack 22 shown in FIG. 2 is prevented.

[0050] 6B is a top view showing a situation in which an impact is applied to the battery pack 10 from the right. Even in this case, even if the plunger 30 hits the battery pack 10 from the right side, the impact is alleviated and absorbed by the components of the battery cover 20. Therefore, the battery pack 10 does not deform significantly, and damage to the battery stack 22 shown in FIG. 2 is prevented.

[0051] The above-described embodiment can provide the following main effects.

[0052] 2, the battery pack 10 has the reinforcement 25, which gives the battery cover 20 itself high rigidity. This increases the rigidity of the entire battery pack 10 including the battery cover 20, and protects the battery stack 22 from collision impacts and the like. Furthermore, by forming the smoke exhaust air passage 26 and the exhaust air passage 27 inside the battery cover 20, there is no need to provide a separate smoke exhaust duct or exhaust duct, and the overall configuration of the battery pack 10 can be simplified.

[0053] Referring to FIG. 4B, the gap formed between the first cover member 23 and the second cover member 24 is relatively large, and therefore, by using this gap as the exhaust air passage 27, the flow of exhaust air in the exhaust air passage 27 is promoted, and the battery stack 22 can be cooled effectively.

[0054] 4B, smoke exhaust port 255 and smoke exhaust port 232 are formed by opening first cover member 23 and reinforcement 25, which are in close contact with each other, and gas 28 can be prevented from flowing into exhaust airflow duct 27 side.

[0055] 5, in the process of manufacturing the battery cover 20, a welding jig 32 can be inserted through the exhaust port 231 to weld the second cover member 24 and the reinforcement 25 together using the jig 32. In other words, there is no need to form a hole in the first cover member 23 specifically for welding.

[0056] Referring to FIG. 6A, by connecting the members constituting the battery cover 20, such as the reinforcement 25, to the frame 33, the effect of strengthening the rigidity of the battery pack 10 can be made significant.

[0057] Although the embodiments of the present invention have been described above, the present invention is not limited to these and can be modified within the scope of the present invention. In addition, the above-described embodiments can be combined with each other.

[0058] 4B, it is possible to interchange smoke exhaust airflow duct 26 and exhaust airflow duct 27. That is, it is possible to form exhaust airflow duct 27 in the center of convex portion 242, and form smoke exhaust airflow ducts 26 on both ends of exhaust airflow duct 27.

[0059] Referring to FIG. 1, the battery pack 10 is not limited to being arranged in the storage space 13 below the rear floor, but may also be arranged in a storage space below the front floor or the like where the driver's seat and passenger seat of the vehicle 11 are located.

[0060] Furthermore, in the above description, the components that make up the battery cover 20 are joined together by welding, but they may also be joined by other joining methods such as fastening. [Explanation of symbols]

[0061] 10 Battery pack 11 vehicles 12 Body 13 Storage Space 20 Battery cover 21 Battery case 22 Battery Stack 23 First cover member 231 Exhaust port 232 Smoke exhaust port 24 Second cover member 241 Anterior flat area 242 Convex part 243 Central flat area 244 Posterior flat area 245 Ridge 25 Reinforce 251 Anterior flat area 252 Concave part 253 Posterior flat area 254 Ridge 255 Smoke exhaust port 26 Smoke exhaust air duct 27 Exhaust air duct 28 Gas 29 Air 30 Pusher 31 Smoke exhaust opening 32 Jig 33 frames 34 Previous Frame 35 rear frame 36 Right Frame 37 Left Frame 38 Smoke exhaust passage section 40 Cover Frame

Claims

1. a battery cover that covers a battery stack housed in the battery pack; The device includes a first cover member, a second cover member, a reinforcement, a smoke exhaust air duct, and an exhaust air duct, the first cover member covers the battery stack from above, the second cover member is joined to the first cover member from above, the reinforcement extends along the longitudinal direction of the battery stack and is disposed between the first cover member and the second cover member; the smoke exhaust duct is an air duct through which gas generated from the battery stack is exhausted, the exhaust air passage is an air passage through which air that has exchanged heat with the battery stack is discharged, The smoke exhaust air passage and the exhaust air passage are formed in a gap formed between the first cover member, the second cover member, and the reinforcement, The smoke exhaust air passage is formed between the reinforcement and the second cover member, The battery cover is characterized in that the exhaust air passage is formed between the first cover member and the second cover member.

2. By opening the first cover member at a portion where the exhaust air passage is formed, an exhaust port is formed through which air that has exchanged heat with the battery stack flows into the exhaust air passage, The battery cover of claim 1, characterized in that by opening the first cover member and the reinforcement, which are in close contact with each other, in the portion where the smoke exhaust airflow path is formed, a smoke exhaust port is formed through which gas generated from the battery stack flows into the smoke exhaust airflow path.

3. A battery cover that covers a battery stack housed in a battery pack, The device includes a first cover member, a second cover member, a reinforcement, a smoke exhaust air duct, and an exhaust air duct, the first cover member covers the battery stack from above, the second cover member is joined to the first cover member from above, the reinforcement extends along the longitudinal direction of the battery stack and is disposed between the first cover member and the second cover member; the smoke exhaust duct is an air duct through which gas generated from the battery stack is exhausted, the exhaust air passage is an air passage through which air that has exchanged heat with the battery stack is discharged, The smoke exhaust air passage and the exhaust air passage are formed in a gap formed between the first cover member, the second cover member, and the reinforcement, the battery pack has a frame disposed outside the battery stack; A battery cover characterized in that the end side of the reinforcement is connected to the frame.

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