Battery box and battery pack

Abstract

The present invention relates to the field of battery technology, and discloses a battery box and a battery pack. The battery box includes: a bottom plate, a frame and a cover plate, the frame and the bottom plate are arranged to form a battery accommodating space, the cover plate and the frame are fixed by fasteners, the cover plate and at least one frame are fixed by fasteners, the frame has a connecting surface, the connecting surface has a first fixing surface and a second fixing surface, the first fixing surface is arranged parallel to the bottom plate, the second fixing surface is arranged at an angle to the bottom plate, and the height H of the second fixing surface in a direction perpendicular to the bottom plate is 200mm-250mm. By changing the angle of the connecting surface part of the frame, the fastening direction of the fastener at the second fixing surface has an angle with the vibration direction of the battery box when it vibrates, the connection strength of the fastener is enhanced, the cover plate and the frame are reliably fixed, and the sealing performance at the frame and the cover plate is ensured. The height H of the second fixing surface is set to 200mm-250mm, which ensures the fixing effect while avoiding cost waste.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery box and a battery pack. Background Art

[0002] With the development and popularization of new energy vehicles, batteries, as one of the core components of hybrid vehicles and pure electric vehicles, have also attracted much attention in their development and research and development. The safety performance of batteries has become an increasingly important indicator for people to evaluate the performance of batteries.

[0003] An existing battery pack for automobiles is composed of a battery box and a plurality of battery groups. The battery box includes a box body and a cover plate. The box body has a top opening, and the cover plate is arranged at the top opening. The box body includes a bottom plate, four side plates and four frames. The four frames are arranged on the tops of the four side plates in a one-to-one correspondence. The frames and the cover plate are fixed together by fasteners. The fixing surfaces of the frames and the cover plate are arranged parallel to the bottom plate. During the vibration of the battery pack, the fastening direction of the fasteners is the same as the vibration direction, which will reduce the connection strength of the fastening of the fasteners, thereby causing poor fixation of the cover plate and the frame during use, resulting in loss of sealing and affecting the safety performance of the battery pack. Summary of the invention

[0004] In view of this, the present invention provides a battery box and a battery pack to solve the problem that the cover plate and the frame are poorly fixed due to the first fixing surfaces of the frame and the cover plate being arranged parallel to the bottom plate.

[0005] In the first aspect, the present invention provides a battery box, comprising: a bottom plate, a frame and a cover plate, the frame and the bottom plate are arranged to form a battery accommodating space, the cover plate is used to seal the battery accommodating space, the frame extends from one side of the bottom plate in a direction perpendicular to the bottom plate, the cover plate and at least one frame are fixed by fasteners, the frame has a connecting surface fastened to the cover plate, the connecting surface is the edge surface of the frame, the fastening direction of the fastener is perpendicular to the connecting surface, the connecting surface has a first fixing surface and a second fixing surface, the first fixing surface is arranged parallel to the bottom plate, the second fixing surface is arranged at an angle to the bottom plate, and the height H of the second fixing surface in the direction perpendicular to the bottom plate is 200mm-250mm.

[0006] In a second aspect, the present invention further provides a battery pack, comprising: the above-mentioned battery case; and a battery pack disposed in the battery case.

[0007] Beneficial effects: The fixing surface includes a first fixing surface parallel to the bottom plate and a second fixing surface set at an angle to the bottom plate. By changing the angle of the connecting surface portion of the frame, the fastening direction of the fastener at the second fixing surface forms an angle with the vibration direction of the battery box when it vibrates, thereby enhancing the connection strength of the fastener, making the cover plate and the frame reliably fixed, thereby ensuring the sealing performance at the frame and the cover plate. The height H of the second fixing surface is also the vertical dimension of the second fixing surface. The height H of the second fixing surface cannot be too small or too large. If the height H of the second fixing surface is too small, it means that more fasteners cannot be fixed on the second fixing surface, and the connection strength between the frame and the cover plate cannot be guaranteed; if the height H of the second fixing surface is too large, it means that the height dimension of the frame is large and the material cost is high. Therefore, the height H of the second fixing surface is set to 200mm-250mm, so that the height of the second fixing surface is within an appropriate range, ensuring the fixing effect while avoiding cost waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0009] Figure 1 A three-dimensional diagram of a battery box according to an embodiment of the present invention;

[0010] Figure 2 for Figure 1 An exploded view of the battery box shown;

[0011] Figure 3 for Figure 2 A partial schematic diagram of the sealing gasket shown;

[0012] Figure 4 A three-dimensional diagram of a first frame according to an embodiment of the present invention;

[0013] Figure 5 This is a schematic structural diagram of a second frame according to an embodiment of the present invention;

[0014] Figure 6 This is a schematic structural diagram of a third frame according to an embodiment of the present invention;

[0015] Figure 7 This is a schematic structural diagram of a fourth frame according to an embodiment of the present invention;

[0016] Figure 8 is a schematic structural diagram of a fifth frame according to an embodiment of the present invention;

[0017] Fig. 9 It is a schematic structural diagram of a sixth frame according to an embodiment of the present invention.

[0018] Description of reference numerals:

[0019] 1. Bottom plate;

[0020] 2. frame; 201. first fixed surface; 2011. upper plane; 2012. lower plane; 202. second fixed surface; 203. arc surface;

[0021] 3. Cover plate;

[0022] 4. Sealing gasket. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0024] Combine the following Figures 1 to 9 , describing an embodiment of the present invention.

[0025] According to an embodiment of the present invention, on the one hand, a battery box is provided, comprising: a bottom plate 1, a frame 2 and a cover plate 3, the frame 2 and the bottom plate 1 are arranged to form a battery accommodating space, the cover plate 3 is used to seal the battery accommodating space, the frame 2 extends from one side of the bottom plate 1 along a direction perpendicular to the bottom plate 1, the cover plate 3 is fixed to at least one frame 2 by fasteners, the frame 2 has a connecting surface fastened to the cover plate 3, the connecting surface is the edge surface of the frame 2, the fastening direction of the fastener is perpendicular to the connecting surface, the connecting surface has a first fixing surface 201 and a second fixing surface 202, the first fixing surface 201 is arranged parallel to the bottom plate 1, the second fixing surface 202 is arranged at an angle to the bottom plate 1, and the height H of the second fixing surface 202 in the direction perpendicular to the bottom plate 1 is 200mm-250mm.

[0026] The battery box body of this embodiment has a fixing surface including a first fixing surface 201 parallel to the bottom plate and a second fixing surface 202 arranged at an angle to the bottom plate 1. By changing the angle of the connecting surface portion of the frame 2, the fastening direction of the fastener at the second fixing surface 202 forms an angle with the vibration direction of the battery box body when it vibrates, thereby enhancing the connection strength of the fastener, making the cover plate 3 and the frame 2 fixed reliably, thereby ensuring the sealing performance at the frame 2 and the cover plate 3. The height H of the second fixing surface 202 is also Figures 5 to 9The vertical dimension of the second fixing surface 202 in the embodiment of the present invention, the height H of the second fixing surface 202 should be neither too small nor too large. If the height H of the second fixing surface 202 is too small, it means that more fasteners cannot be fixed on the second fixing surface 202, and the connection strength between the frame 2 and the cover plate 3 cannot be guaranteed; if the height H of the second fixing surface 202 is too large, it means that the height dimension of the frame 2 is large, and the material cost is high. Therefore, the height H of the second fixing surface 202 is set to 200mm-250mm, so that the height of the second fixing surface 202 is within a suitable range, ensuring the fixing effect while avoiding cost waste.

[0027] Specifically, the angle between the second fixing surface 202 and the base plate 1 is in the range of 5°-175°. If the angle between the second fixing surface 202 and the base plate 1 is too small or too large, it means that the fastening direction of the fastener at the second fixing surface 202 is closer to the vibration direction, and the connection strength of the fastener is weaker. The angle between the second fixing surface 202 and the base plate 1 is set to 5°-175°, that is, the angle between the second fixing surface 202 and the base plate 1 is set within a reasonable range to ensure the connection strength of the fastener, so that the cover plate 3 and the frame 2 are reliably fixed.

[0028] Further, the height H of the second fixing surface 202 may be selected as 210 mm, 220 mm, 225 mm, 230 mm, 235 mm or 240 mm.

[0029] In one embodiment, the ratio of the fixed length L1 of the second fixing surface 202 along its extension direction and the cover plate 3 to the fixed length L of the frame 2 along its extension direction and the cover plate 3 is 20%-50%. The fixed length L1 of the second fixing surface 202 and the cover plate 3 refers to the sum of the lengths of all the second fixing surfaces 202 along their extension direction, the fixed length L of the frame 2 and the cover plate 3 refers to the sum of L1 and the length L2 of all the first fixing surfaces 201 along their extension direction, and the length L2 of the first fixing surface 201 refers to the length of the first fixing surface 201 in the extension direction. Figure 1 The width dimension of the battery box.

[0030] Furthermore, the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the fixed length L of the frame 2 and the cover plate 3 should be neither too large nor too small. If the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the fixed length L of the frame 2 and the cover plate 3 is too large, the length of the second fixed surface 202 is too long, so that the width of the battery box cannot be guaranteed, thereby affecting the capacity of the battery box; if the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the fixed length L of the frame 2 and the cover plate 3 is too small, the length of the second fixed surface 202 is too short and the effect of improving the fixation cannot be achieved.

[0031] Therefore, the ratio of the fixed length L1 of the second fixing surface 202 and the cover plate 3 to the fixed length L of the frame 2 and the cover plate 3 is set to 20%-50%, so that the ratio of L1 and L is within a suitable range, ensuring the width of the battery box while improving the fixing effect.

[0032] Furthermore, the ratio of the fixed length L1 between the second fixing surface 202 and the cover plate 3 to the fixed length L between the frame 2 and the cover plate 3 may be 30%, 35%, 40% or 45%.

[0033] It should be noted that in Figures 4 to 9 Two second fixing surfaces 202 are provided in Figure 5 , Figure 8 and Fig. 9 In, L1=H+H; Figure 6 and Figure 7 In, L1=L3+L4; in Figure 6 In, L2=L5+L6; in Figure 7 and Figure 8 In the middle, L2=L5+L6+L7; Figure 4 and Figure 5 The frame 2 has the same structure as the frame 2, and the only difference is that the height of the second fixing surface 202 is different. Figure 4 In the embodiment, the height of the second fixing surface 202 is almost the same as the height of the frame. Figure 5 In the embodiment, the height of the second fixing surface 202 is smaller than the height of the frame 2 .

[0034] It is worth noting that the battery box has a length direction, a height direction, and a width direction. The length direction, height direction, and width direction of the battery box can be referred to Figure 1 shown.

[0035] In one embodiment, the ratio of the fixing length L1 of the second fixing surface 202 and the cover plate 3 to the width D1 of the first fixing surface 201 perpendicular to its extension direction is 7.3-14.6. Figure 1 The length dimension of the battery box.

[0036] Furthermore, the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the width D1 of the first fixed surface 201 should be neither too large nor too small. If the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the width D1 of the first fixed surface 201 is too large, it means that the narrower the width of the first fixed surface 201, the higher the sealing requirement; if the ratio of the fixed length L1 of the second fixed surface 202 and the cover plate 3 to the width D1 of the first fixed surface 201 is too small, it means that the wider the width of the first fixed surface 201, the larger the width of the frame 2, which makes the width of the sealing gasket 4 also larger and the material cost higher.

[0037] Therefore, the ratio of the fixed length L1 of the second fixing surface 202 and the cover plate 3 to the width D1 of the first fixing surface 201 is set to 7.3-14.6, so that the ratio of L1 to D1 is within a suitable range, reducing the sealing difficulty while controlling the material cost.

[0038] Further, the ratio of the fixing length L1 of the second fixing surface 202 and the cover plate 3 to the width D1 of the first fixing surface 201 may be 8, 9, 10, 10.5, 11, 12 or 13.

[0039] In one embodiment, Fig. 9 As shown, the second fixed surface 202 and the first fixed surface 201 transition through the arc surface 203. If the second fixed surface 202 and the first fixed surface 201 do not transition through the arc surface 203, the cross section of the intersection of the second fixed surface 202 and the first fixed surface 201 changes suddenly, and then stress concentration is easily generated at the intersection, which reduces the structural strength of the frame 2 and affects the life and stability of the frame 2. At the same time, when the sealing gasket 4 is arranged on the second fixed surface 202 and the first fixed surface 201, a small gap is easily generated at the intersection of the sealing gasket 4 and the second fixed surface 202 and the first fixed surface 201, and the sealing performance is also reduced. Therefore, the arc surface 203 is arranged between the second fixed surface 202 and the first fixed surface 201, so that the first fixed surface 201 smoothly transitions to the second fixed surface 202 through the arc surface 203, which can avoid stress concentration, improve the structural strength of the frame 2, and also make the sealing of the sealing gasket 4 at the arc surface 203 reliable and more controllable.

[0040] In one embodiment, a sealing gasket 4 is disposed on the second fixing surface 202 and the first fixing surface 201 , the width of the sealing gasket 4 is W, the radius of the outer fillet of the sealing gasket 4 is R1 , and the radius of the inner fillet of the sealing gasket 4 is R2 , wherein R1<R2+14.3W.

[0041] Furthermore, the friction between the upper surface of the sealing gasket 4 and the cover plate 3 is , the friction between the lower surface of the sealing gasket 4 and the frame 2 , =R1 W / 4, =R2 W / 4, R1=R2+t, F=P 水 S 侧面 =ρ g h (R1 2 -R2 2 ) / 8, where is the post-compression stress of the sealing gasket 4, The friction coefficient between the upper surface of the sealing gasket 4 and the cover plate 3, is the area of ​​the upper surface of the sealing gasket 4; The friction coefficient between the lower surface of the sealing pad 4 and the frame 2, is the area of ​​the lower surface of the sealing gasket 4, R1 is the radius of the outer fillet of the sealing gasket 4 or the radius of the inner fillet of the cover plate 3, W is the width of the sealing gasket 4; R2 is the radius of the inner fillet of the sealing gasket 4 or the radius of the outer fillet of the frame 2, t is the thickness of the sealing gasket 4 after compression, F is the water pressure thrust when submerged, ρ is the water density, h is the water depth, and g is the acceleration of gravity.

[0042] To ensure sealing, the friction between the gasket 4 and the cover plate 3 or the frame 2 needs to be greater than the pressure of water on the gasket 4, that is, f1+f2>F. According to the IP68 test water depth of 2m, the comprehensive friction coefficient is 0.5. Taking 280kPa, we can get the relationship between the radius of the arc transition zone of the sealing gasket 4 and the width of the sealing gasket 4: R1<R2+14.3W. Meeting this relationship can improve the sealing performance of the sealing gasket 4 at the arc, thereby ensuring the safety performance of the battery box.

[0043] In one embodiment, the second fixing surface 202 is arranged perpendicular to the bottom plate 1. The second fixing surface 202 is arranged perpendicular to the bottom plate 1, which is more convenient to process the frame 2 and reduces the manufacturing cost. At the same time, the number of the arc surfaces 203 can be reduced to further ensure the sealing performance.

[0044] Furthermore, if Figure 4 , Figure 5 and Fig. 9 As shown, the second fixing surfaces 202 are arranged at both ends of the first fixing surface 201. At this time, the two second fixing surfaces 202 and the first fixing surface 201 are in an inverted "U" shape; two second fixing surfaces 202 can also be arranged in the middle of the first fixing surface 201 (such as Figure 6 and Figure 8 As shown in FIG. 2 ), the two second fixing surfaces 202 divide the first fixing surface 201 into two upper planes 2011 and a lower plane 2012 (as shown in FIG. 2 ). Figure 8 As shown in the figure, the lower plane 2012 is located below the upper plane 2011, and the lower plane 2012 is arranged between the two second fixing surfaces 202.

[0045] Specifically, the ratio of the fixed length L1 of the second fixing surface 202 and the cover plate 3 to the fixed length L of the frame 2 and the cover plate 3 is 7%-90%. When the second fixing surface 202 is perpendicular to the bottom plate 1, it is also perpendicular to the first fixing surface 201. The fastening direction of the fastener at the second fixing surface 202 is perpendicular to the vibration direction of the battery box when it vibrates, so that the fixing strength of the cover plate 3 and the frame 2 is higher, and the requirement for L1 is lower at this time, and the ratio of L1 to L can be smaller.

[0046] In another implementation, Figure 6 to Figure 7 As shown, the included angle between the second fixing surface 202 and the bottom plate 1 is an acute angle or an obtuse angle. The second fixing surfaces 202 can be arranged at both ends of the first fixing surface 201, or two second fixing surfaces 202 can be arranged in the middle of the first fixing surface 201, and the two second fixing surfaces 202 are "V-shaped" (such as Figure 6 Alternatively, the two second fixing surfaces 202 are spaced apart, and the two second fixing surfaces 202 divide the first fixing surface 201 into two upper planes 2011 and one lower plane 2012 (as shown in FIG. Figure 7 As shown in the figure, the lower plane 2012 is located below the upper plane 2011, and the lower plane 2012 is arranged between the two second fixing surfaces 202.

[0047] It is worth noting that when the shape of the frame 2 changes, the cover plate 3 is also set to a matching shape at the corresponding position.

[0048] In one embodiment, the frame 2 is a die-casting. The frame 2 is manufactured by a die-casting process to ensure the structural strength of the frame 2. The die-casting process has the advantages of good product quality, high production efficiency, smooth surface, and low cost.

[0049] In one embodiment, the ratio of the thickness T of the frame 2 to the height H of the second fixing surface 202 is 0.4%-0.8%. If the thickness of the frame 2 is thicker, it means that the contact area between the fastener and the frame 2 is larger, and the connection strength between the frame 2 and the cover plate 3 is higher. In this case, the height of the second fixing surface 202 can be reduced; if the thickness of the frame 2 is thinner, it means that the contact area between the fastener and the frame 2 is smaller, and the connection strength between the frame 2 and the cover plate 3 is smaller. In this case, the height of the second fixing surface 202 can be increased. Therefore, the ratio of the thickness T of the frame 2 to the height H of the second fixing surface 202 is set to 0.4%-0.8%, so that the ratio of T to H is within a suitable range, which effectively ensures the connection strength between the cover plate 3 and the frame 2.

[0050] Furthermore, the ratio of the thickness T of the frame 2 to the height H of the second fixing surface 202 may be 0.5%, 0.55%, 0.6%, 0.65%, 0.68% or 0.7%.

[0051] In one embodiment, there are two frames 2 , which are a front frame and a rear frame. The front frame is arranged on the front side of the bottom plate 1 , and the rear frame is arranged on the rear side of the bottom plate 1 .

[0052] Furthermore, when the second fixed surface 202 is arranged at both ends of the first fixed surface 201, the left panel and the right panel may not be arranged on the left and right sides of the bottom plate 1, or the left panel and the right panel may be arranged. When the left panel and the right panel are arranged, the height of the left panel and the right panel is less than the height of the front frame and the rear frame.

[0053] Further, when the second fixing surface 202 is disposed in the middle of the first fixing surface 201 , a left panel and a right panel need to be disposed on the left and right sides of the bottom plate 1 .

[0054] It should be noted that the directions of up, down, front, back, left and right are Figure 1 The arrows in the middle point to the directions of “up, down, front, back, left, right”.

[0055] According to an embodiment of the present invention, on the other hand, a battery pack is provided, comprising: the above-mentioned battery case and a battery pack, wherein the battery pack is arranged in the battery case.

[0056] Furthermore, the battery pack includes a number of batteries connected in series and / or in parallel. The battery includes a battery casing, a battery cell, etc. The battery cell is arranged inside the battery casing. The battery cell is a wound battery cell or a stacked battery cell, etc. The battery can adopt the structure in the prior art and will not be described in detail here.

[0057] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery box, characterized in that: include: A base plate (1), a frame (2) and a cover plate (3), wherein the frame (2) and the base plate (1) are arranged to enclose a battery storage space, and the cover plate (3) is used to seal the battery storage space. The frame (2) is extended from one side of the base plate (1) in a direction perpendicular to the base plate (1). The cover plate (3) is fixed to at least one of the frames (2) by a fastener. The frame (2) has a connection surface fastened to the cover plate (3), and the connection surface is an edge surface of the frame (2). The fastening direction of the fastener is perpendicular to the connection surface. The connection surface has a first fixing surface (201) and a second fixing surface (202). The first fixing surface (201) is arranged parallel to the base plate (1), and the second fixing surface (202) is arranged at an angle to the base plate (1). The height H of the second fixing surface (202) in a direction perpendicular to the base plate (1) is 200 mm-250 mm. The second fixing surface (202) and the first fixing surface (201) are transitioned via an arc surface (203); a sealing gasket (4) is provided on the second fixing surface (202) and the first fixing surface (201); the width of the sealing gasket (4) is W, the radius of the outer fillet of the sealing gasket (4) is R1, and the radius of the inner fillet of the sealing gasket (4) is R2, wherein R1<R2+14.3W.

2. The battery box according to claim 1, characterized in that: The ratio of a fixed length L1 of the second fixing surface (202) along its extension direction and the cover plate (3) to a fixed length L of the frame (2) along its extension direction and the cover plate (3) is 20%-50%.

3. The battery case according to claim 1 or 2, characterized in that: The ratio of the fixing length L1 of the second fixing surface (202) along its extension direction and the cover plate (3) to the width D1 of the first fixing surface (201) perpendicular to its extension direction is 7.3-14.

6.

4. The battery case according to claim 1 or 2, characterized in that: The second fixing surface (202) is arranged perpendicular to the bottom plate (1).

5. The battery box according to claim 1, characterized in that: The ratio of a fixed length L1 of the second fixing surface (202) along its extension direction and the cover plate (3) to a fixed length L of the frame (2) along its extension direction and the cover plate (3) is 7%-90%.

6. The battery case according to claim 1 or 2, characterized in that: The frame (2) is a die-casting part.

7. The battery case according to claim 1 or 2, characterized in that: The ratio of the thickness T of the frame (2) to the height H of the second fixing surface (202) is 0.4%-0.8%.

8. A battery pack, characterized in that: include: The battery case according to any one of claims 1 to 7; The battery pack is arranged in the battery box.

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