Battery shell assembly and battery

Abstract

The invention relates to the technical field of batteries, and particularly discloses a battery shell assembly and a battery, and the battery shell assembly comprises a battery shell, a first plastic part, a second plastic part and a pole. The pole group is positioned in the mounting cavity of the battery shell; a first mounting hole is formed in one wall of the battery shell; the first plastic part is arranged outside the mounting cavity and connected to the wall provided with the first mounting hole in a hot melting mode. The second plastic part is arranged in the mounting cavity and connected to the wall provided with the first mounting hole in a hot melting mode. The pole column is positioned on one side, deviating from the battery shell, of the first plastic part; the tab of the pole group penetrates through the second plastic part, the first mounting hole and the first plastic part and then is connected with the pole column. The pole is arranged outside the mounting cavity of the battery shell, and the thickness of the second plastic part is relatively thin, so that the internal space of the battery shell is saved, the volume of the pole group is increased, the space utilization rate is high, and the energy density of the battery is favorably improved. The invention also provides a battery which comprises the battery shell assembly.

Description

Technical Field

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

[0002] In lithium-ion batteries, the connecting piece and one end of the pole are generally arranged in the battery housing, and the other end of the pole passes through the battery housing and is connected to the external circuit to lead out the pole group to realize the power supply or energy storage of the battery. A lower plastic part is arranged between the end of the pole located in the battery housing and the battery housing, and the pole is insulated from the battery housing by the lower plastic part, and the lower plastic part is also located in the battery housing.

[0003] Since one end of the pole is arranged in the battery shell and the thickness of the lower plastic part is relatively large, the pole and the lower plastic part will occupy part of the space inside the battery shell, the arrangement space of the pole group is reduced, the space utilization inside the battery shell is low, and the energy density of the battery is low. Summary of the invention

[0004] The object of the present invention is to provide a battery housing assembly and a battery, wherein the pole is arranged outside the battery housing, and the thickness of the second plastic part located inside the battery housing is relatively thin, the space utilization rate inside the battery housing is high, the volume of the pole group is relatively large, which is conducive to improving the energy density of the battery.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] In one aspect, the present invention provides a battery housing assembly, comprising:

[0007] A battery housing, wherein the interior is hollow to form a mounting cavity, one side of the battery housing has an opening communicating with the mounting cavity, the electrode group is loaded into the mounting cavity through the opening, and a first mounting hole is provided on one wall of the battery housing;

[0008] A first plastic part, disposed outside the mounting cavity and connected by hot melt to the wall provided with the first mounting hole, wherein the first plastic part is provided with a first through hole;

[0009] A second plastic part is disposed in the installation cavity and is connected to the wall provided with the first installation hole by heat melting, and a second through hole is provided on the second plastic part;

[0010] The pole is located on a side of the first plastic part away from the battery housing, and the pole lug of the pole group is connected to the pole after passing through the second through hole, the first mounting hole and the first through hole.

[0011] Optionally, the battery housing includes a top wall and a peripheral side wall, the top wall and the peripheral side wall surround the mounting cavity, and the first mounting hole is provided on the top wall.

[0012] Optionally, one of the first plastic part and the top wall is provided with a first melting column, and the other of the first plastic part and the top wall is provided with a first fixing groove, and the first melting column is inserted and fixed in the first fixing groove by melting;

[0013] And / or, one of the second plastic part and the top wall is provided with a second melting column, and the other of the second plastic part and the top wall is provided with a second fixing groove, and the second melting column is inserted and fixed in the second fixing groove by melting.

[0014] Optionally, the shape of the cross section of the first fixing groove matches the shape of the cross section of the first melting column, and the shape of the cross section of the first melting column is one of a circle, a waist shape and a polygon;

[0015] And / or, the shape of the cross section of the second fixing groove matches the shape of the cross section of the second melting column, and the shape of the cross section of the second melting column is one of a circle, a waist shape and a polygon.

[0016] Optionally, a first overflow groove is recessed on the groove wall of the first fixing groove;

[0017] And / or, a second overflow groove is recessed on the groove wall of the second fixing groove.

[0018] Optionally, the first fixing groove is one of a straight groove, a trapezoidal groove and a stepped groove;

[0019] And / or, the first overflow groove is one of a straight groove, a trapezoidal groove and a stepped groove;

[0020] And / or, the second fixing groove is one of a straight groove, a trapezoidal groove and a stepped groove;

[0021] And / or, the second overflow groove is one of a straight groove, a trapezoidal groove and a stepped groove.

[0022] Optionally, the first plastic part includes a first plastic part body, the first through hole is provided in the first plastic part body, a lap portion is provided in the circumference of the first plastic part body, a sink groove is provided on the end surface of the top wall facing away from the second plastic part, the lap portion is embedded in the sink groove and fits with the bottom wall of the sink groove;

[0023] Wherein, along the first direction, the thickness of the top wall is H, and the distance between the end surface of the overlapping portion facing away from the second plastic part and the end surface of the top wall facing away from the second plastic part is b;

[0024] The value range of b satisfies: -1mm≤b≤0.5H, 1mm≤H≤3mm;

[0025] and / or, along the second direction, the width of the overlap portion is c;

[0026] The value range of c satisfies: 0mm≤c≤10mm.

[0027] Optionally, a first flange and a connecting rib are provided on the side of the first plastic part body facing away from the second plastic part, the first flange is arranged in the circumference of the first through hole, the first flange, the connecting rib and the first plastic part body form a mounting groove, and at least part of the pole is embedded in the mounting groove.

[0028] Optionally, the second plastic part includes a second plastic part body and a second flange, the second through hole is arranged in the second plastic part body, the second flange is arranged in the circumference of the second through hole, and the second flange extends into the first mounting hole and fits with the inner wall of the first mounting hole.

[0029] On the other hand, the present invention provides a battery, comprising a base plate, a pole group, and a battery housing assembly in any of the above schemes, wherein the base plate is connected to an opening of the battery housing, and the pole group is encapsulated in a mounting cavity of the battery housing.

[0030] The beneficial effects of the present invention are:

[0031] The present invention provides a battery shell assembly, comprising a battery shell, a first plastic part, a second plastic part and a pole. The pole group is installed in the installation cavity of the battery shell through an opening, and a first installation hole is provided on one of the walls of the battery shell. The first plastic part is arranged outside the installation cavity and is connected to the wall provided with the first installation hole by heat melting, and a first through hole is provided on the first plastic part. The second plastic part is arranged in the installation cavity and is connected to the wall provided with the first installation hole by heat melting, and a second through hole is provided on the second plastic part. The pole column is located on the side of the first plastic part away from the battery shell, and the pole ear of the pole group passes through the second through hole, the first installation hole and the first through hole and is connected to the pole column, and the pole group is connected to the external circuit through the pole column. Since the pole column is arranged outside the installation cavity of the battery shell and the thickness of the second plastic part is relatively thin, it will not occupy too much space inside the battery shell, the volume of the pole group is increased, the space utilization rate is high, and it is helpful to improve the energy density of the battery.

[0032] The present invention also provides a battery, comprising a bottom plate, a pole group, and the above-mentioned battery housing assembly, wherein the bottom plate is connected to the opening of the battery housing to encapsulate the pole group in the mounting cavity of the battery housing. By adopting the above-mentioned battery housing assembly, the space utilization rate inside the battery housing is high, the volume of the pole group is increased, and the energy density of the battery is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0034] Figure 1 A schematic diagram of the structure of a battery housing assembly provided in an embodiment of the present invention;

[0035] Figure 2 An exploded view of a battery housing assembly provided in an embodiment of the present invention;

[0036] Figure 3 An exploded view of a battery housing assembly provided in an embodiment of the present invention from another perspective;

[0037] Figure 4 A top view of a battery housing assembly provided in an embodiment of the present invention;

[0038] Figure 5 for Figure 4 Sectional view of the AA section;

[0039] Figure 6 for Figure 5 A partial enlarged view of point D in the middle;

[0040] Figure 7 Schematic diagram of the structure of the first fixing groove (second fixing groove) provided in an embodiment of the present invention Figure 1 ;

[0041] Figure 8 Schematic diagram of the structure of the first fixing groove (second fixing groove) provided in an embodiment of the present invention Figure 2 ;

[0042] Fig. 9 Schematic diagram of the structure of the first fixing groove (second fixing groove) provided in an embodiment of the present invention Figure 3 ;

[0043] Fig.10 It is a structural schematic diagram of a first plastic part provided in an embodiment of the present invention;

[0044] Fig.11 for Figure 4 Sectional view of the middle BB section;

[0045] Fig.12 for Fig.11 A partial enlarged view of point E in the middle;

[0046] Fig.13 for Figure 4Sectional view of the CC section;

[0047] Fig.14 for Fig.13 A partial enlarged view of point F in the middle.

[0048] In the figure:

[0049] 100, battery housing; 110, top wall; 111, first mounting hole; 112, sink; 113, first fixing groove; 1131, first overflow groove; 114, second fixing groove; 1141, second overflow groove; 115, second mounting hole; 116, supporting rib; 117, first injection hole; 120, peripheral side wall; 121, opening;

[0050] 200, first plastic part; 210, first plastic part body; 211, first through hole; 220, overlapping part; 230, first flange; 240, connecting rib; 241, mounting groove; 250, first melting column;

[0051] 300, second plastic part; 310, second plastic part body; 311, second through hole; 320, second flange; 330, second melting column; 340, vent hole; 350, second injection hole;

[0052] 400. Explosion-proof valve. DETAILED DESCRIPTION

[0053] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0057] like Figure 1-Figure 3 As shown, this embodiment provides a battery housing assembly, which includes a battery housing 100, a first plastic part 200, a second plastic part 300 and a pole.

[0058] The battery housing 100 is hollow inside to form a mounting cavity. One side of the battery housing 100 has an opening 121 connected to the mounting cavity. The electrode group is installed in the mounting cavity through the opening 121. One wall of the battery housing 100 is provided with a first mounting hole 111. The first plastic part 200 is arranged outside the mounting cavity and is connected to the wall provided with the first mounting hole 111 by heat melting. The first plastic part 200 is provided with a first through hole 211. The second plastic part 300 is arranged in the mounting cavity and is connected to the wall provided with the first mounting hole 111 by heat melting. The second plastic part 300 is provided with a second through hole 311. The pole is in the shape of a plate, and the pole is located on the side of the first plastic part 200 away from the battery housing 100. The pole ear of the pole group passes through the second through hole 311, the first mounting hole 111 and the first through hole 211 and then bends to one side. The pole ear outside the mounting cavity is connected to the end face of the pole close to the battery housing 100, and the pole group is connected to the external circuit through the pole.

[0059] Since the pole in this embodiment is arranged outside the mounting cavity of the battery housing 100, the pole does not occupy the space inside the battery housing 100, the volume of the pole group is increased, the space utilization rate of the mounting cavity is high, and it is helpful to improve the energy density of the battery. Figure 1-Figure 3 The thickness in the Z-axis direction (as shown in the figure) is relatively thin, so the size of the entire battery housing assembly along the first direction is relatively small. When the battery having the battery housing assembly is arranged in a whole battery pack, the space utilization rate is high and the energy density is high.

[0060] As an optional solution, the battery case 100 in this embodiment includes a top wall 110 and a peripheral side wall 120, wherein one end of the peripheral side wall 120 is connected to the top wall 110, and the other end of the peripheral side wall 120 is surrounded to form the above-mentioned opening 121, and the top wall 110 and the peripheral side wall 120 are surrounded to form the above-mentioned installation cavity, the first installation hole 111 is arranged on the top wall 110, the first plastic part 200 and the second plastic part 300 are respectively arranged on both sides of the top wall 110 along the first direction, and the second plastic part 300 is located in the installation cavity.

[0061] See also Figure 4-Figure 6In this embodiment, one of the first plastic part 200 and the top wall 110 is provided with a first melting column 250, and the other of the first plastic part 200 and the top wall 110 is provided with a first fixing groove 113, and the first melting column 250 is inserted and fixed in the first fixing groove 113 by melting. By way of example, in this embodiment, the first melting column 250 is provided on the side of the first plastic part 200 facing the top wall 110, and the first fixing groove 113 is provided on the side of the top wall 110 facing the first plastic part 200. During installation, the first melting column 250 of the first plastic part 200 is inserted into the first fixing groove 113, and the first melting column 250 of the first plastic part 200 is melted by ultrasonic hot melting. The melted first melting column 250 diffuses to various positions in the first fixing groove 113. After the first plastic part 200 and the top wall 110 are cooled, the first melting column 250 is fixed in the first fixing groove 113, so that the first plastic part 200 and the top wall 110 are fixed. This fixing method is relatively simple to operate, and the first plastic part 200 and the top wall 110 have a good appearance after assembly, without exposed joints, and avoids the severe impact on the top wall 110 when the previous riveting method is used. The overall shape of the top wall 110 is good and the flatness is high.

[0062] Continue to see Figure 6 , the first fixed groove 113 in this embodiment can be set as a straight groove, that is, along the first direction, the shape and size of each cross section of the first fixed groove 113 are consistent. The shape of the cross section of the first fixed groove 113 matches the shape of the cross section of the first melting column 250. Exemplarily, the shape of the cross section of the first melting column 250 is one of a circle, a waist shape and a polygon. Here, the shape of the cross section of the first melting column 250 is a circle as an example for illustration. Of course, in other embodiments, the shape of the cross section of the first melting column 250 can be a waist shape, a triangle, a quadrilateral, a pentagon, etc., which are not listed here one by one.

[0063] In some embodiments, the first fixing groove 113 may also be configured as other types. Figure 7 , the first fixing groove 113 can be set as a trapezoidal groove, that is, when approaching the first plastic part 200 along the first direction, the size of the cross section of the first fixing groove 113 gradually decreases, but the shape of the cross section of the first fixing groove 113 remains unchanged. In other words, the notch of the first fixing groove 113 close to the first plastic part 200 has a gradually shrinking trend. As a result, after the first melting column 250 is melted and cooled in the first fixing groove 113, it is not easy to fall out of the first fixing groove 113, and the connection strength between the first plastic part 200 and the top wall 110 is higher, and the connection is more reliable and stable.

[0064] Alternatively, in some embodiments, see Figure 8, the first fixing groove 113 can be set as a stepped groove, that is, the size of the first fixing groove 113 at a certain cross section along the first direction increases or decreases sharply, but the shape of the cross section of the first fixing groove 113 remains unchanged. In other words, the notch of the first fixing groove 113 close to the first plastic part 200 tends to be gradually widened or narrowed. Similarly, after the first melting column 250 is melted and cooled in the first fixing groove 113, it is not easy to fall out of the first fixing groove 113, and the connection strength between the first plastic part 200 and the top wall 110 is higher, and the connection is more reliable and stable.

[0065] More preferably, see Fig. 9 The first overflow groove 1131 is concavely provided on the groove wall of the first fixed groove 113. The first molten column 250 can diffuse into the first overflow groove 1131 after melting, so that a bulge is formed in the circumference of the first molten column 250. When the first plastic part 200 is subjected to a pulling force or pressure away from or close to the top wall 110, the bulge can abut against the groove wall of the first overflow groove 1131, thereby preventing the first molten column 250 from escaping from the first fixed groove 113 and preventing the first molten column 250 from squeezing the groove bottom of the first fixed groove 113, and the connection between the first plastic part 200 and the top wall 110 is more firm and stable. Optionally, the first overflow groove 1131 is one of a straight groove, a trapezoidal groove and a stepped groove.

[0066] See also Figure 4 , Fig.11 and Fig.12 , one of the second plastic part 300 and the top wall 110 is provided with a second melting column 330, and the other of the second plastic part 300 and the top wall 110 is provided with a second fixing groove 114, and the second melting column 330 is inserted and fixed in the second fixing groove 114 by melting. By way of example, in this embodiment, the second melting column 330 is provided on the side of the second plastic part 300 facing the top wall 110, and the second fixing groove 114 is provided on the side of the top wall 110 facing the second plastic part 300. During installation, the second melting column 330 of the second plastic part 300 is inserted into the second fixing groove 114, and the second melting column 330 of the second plastic part 300 is melted by ultrasonic hot melting. The melted second melting column 330 diffuses to various positions in the second fixing groove 114. After the second plastic part 300 and the top wall 110 are cooled, the second melting column 330 is fixed in the second fixing groove 114, so that the second plastic part 300 and the top wall 110 are fixed. This fixing method is relatively simple to operate, and the second plastic part 300 and the top wall 110 have a good appearance after assembly, without exposed joints, and avoids the severe impact on the top wall 110 when the previous riveting method is used. The overall shape of the top wall 110 is good and the flatness is high.

[0067] Continue to see Figure 7-Figure 9 , Fig.12, the structures of the second fixed groove 114 and the second melting column 330 in this embodiment are the same as those of the first fixed groove 113 and the first melting column 250. The second fixed groove 114 can also be set as one of a straight groove, a trapezoidal groove and a stepped groove. A second overflow groove 1141 can also be provided on the groove wall of the second fixed groove 114, and the second overflow groove 1141 is one of a straight groove, a trapezoidal groove and a stepped groove. The shape of the cross section of the second fixed groove 114 matches the shape of the cross section of the second melting column 330. Exemplarily, the shape of the cross section of the second melting column 330 is one of a circle, a waist shape and a polygon. Here, the shape of the cross section of the second melting column 330 is a circle as an example for illustration. Of course, in other embodiments, the shape of the cross section of the second melting column 330 can be a waist shape, a triangle, a quadrilateral, a pentagon, etc., which are not listed here one by one.

[0068] Furthermore, a plurality of second melting columns 330 may be provided, and the plurality of second melting columns 330 are arranged on the second plastic body 310 close to the second plastic body 310 along the third direction ( Figure 2 The second melting pillars 330 are arranged in a spaced-apart manner on the side of the Y-axis direction shown in FIG. 1 , and the direction in which the second melting pillars 330 are arranged in a spaced-apart manner is the second direction ( Figure 2 In the X-axis direction shown in FIG. 1 ). As a result, the force on the second plastic part 300 is more balanced, and the connection strength between the second plastic part 300 and the top wall 110 is improved. Here, six second melting pillars 330 are provided as an example. Three second melting pillars 330 are provided at the side of each second plastic part body 310 along the third direction. Correspondingly, the same number of second fixing grooves 114 are also provided at corresponding positions on the top wall 110. Of course, in other embodiments, the number and arrangement of the second melting pillars 330 and the second fixing grooves 114 can also be flexibly adjusted as needed, and this embodiment does not limit this.

[0069] Continue to see Figure 3 , Figure 6 and Fig.10 In this embodiment, the first plastic part 200 includes a first plastic part body 210, a first through hole 211 and a first melting column 250 are arranged on the first plastic part body 210, and the first melting column 250 is located on the end surface of the first plastic part body 210 close to the top wall 110. There may be a plurality of first melting columns 250, and the plurality of first melting columns 250 are arranged at intervals in the middle position of the first plastic part body 210, thereby making the force on the second plastic part 300 more balanced and improving the connection strength between the first plastic part 200 and the top wall 110. Here, four first melting columns 250 are provided as an example, and the four first melting columns 250 are arranged in a square array on the first plastic part body 210. Accordingly, the same number of first fixing grooves 113 are also provided at corresponding positions on the top wall 110. Of course, in other embodiments, the number and arrangement of the first melting columns 250 and the first fixing grooves 113 can also be flexibly adjusted as needed, and this embodiment does not limit this.

[0070] The first plastic body 210 is provided with a lap joint 220 in the circumferential direction, and a recessed groove 112 is provided on the end surface of the top wall 110 facing away from the second plastic part 300. The lap joint 220 is embedded in the recessed groove 112 and fits the bottom wall of the recessed groove 112. On the one hand, the lap joint 220 can be provided along the axial direction ( Figure 3 The first plastic part 200 is limited in position in the Z-axis direction shown in the figure to ensure accurate positioning between the first plastic part 200 and the top wall 110; on the other hand, the arrangement of the sink 112 can further reduce the movement of the battery housing assembly along the first direction ( Figure 3 The size of the battery (in the Z-axis direction shown in the figure) is improved, thereby improving space utilization and increasing the energy density of the battery.

[0071] Among them, along the first direction, the thickness of the top wall 110 is H, and the distance between the end surface of the lap joint 220 away from the second plastic part 300 and the end surface of the top wall 110 away from the second plastic part 300 is b, and the value range of b satisfies: -1mm≤b≤0.5H, 1mm≤H≤3mm. Wherein "-" indicates that the end surface of the lap joint 220 away from the second plastic part 300 exceeds the end surface of the top wall 110 away from the second plastic part 300. Exemplarily, when the value of H is 1mm, the value of b can be -1mm, 0mm, 0.5mm. When the value of H is 3mm, the value of b can be -1mm, 0mm, 0.5mm, 1mm, 1.5mm. It should be noted that the value of b should not be too large. If the value of b is greater than 0.5H, the depth of the sink 112 is large, which affects the structural strength of the top wall 110. When the top wall 110 is bumped, it is easy to deform or break, resulting in battery failure. Of course, the value of b should not be too small. If the value of b is less than -1mm, the end surface of the overlapping portion 220 that is away from the second plastic part 300 exceeds the end surface of the top wall 110 that is away from the second plastic part 300 too much, and the height of the pole along the first direction increases, which is not conducive to improving the space utilization and may affect the assembly between the first plastic part 200 and other structural parts.

[0072] Further, see Figure 5 and Figure 6 , along the second direction ( Figure 5), the width of the overlap portion 220 is c, and the value range of c satisfies: 0mm≤c≤10mm. Exemplarily, the value of c can be 0mm, 1mm, 2mm, 5mm, 8mm or 10mm. By controlling the width c of the overlap portion 220 within the above range, it is possible to ensure that the assembly structure between the first plastic part 200 and the top wall 110 is stable, and the weight of the first plastic part 200 can be relatively reduced, thereby reducing material costs. It should be noted that when the width c of the overlap portion 220 is 0mm, the circumferential edge of the first plastic part body 210 overlaps the top wall 110, and at this time, the successful assembly of the first plastic part 200 and the top wall 110 can also be ensured. In addition, when the width c of the overlap portion 220 is greater than 10mm, it may occupy more space in the sink 112, affecting the assembly between the top wall 110 and other structural parts. Optionally, see Fig.13 and Fig.14 , along the third direction ( Fig.13 The width of the overlapped portion 220 in the circumferential direction of the first plastic body 210 is also c, and the value range of c satisfies: 0mm≤c≤10mm. For example, the value of c can be 0mm, 1mm, 2mm, 5mm, 8mm or 10mm.

[0073] The following is a pressure test and a thrust test on the dimension design of the overlap portion 220 and the dimension design of the battery housing 100 using samples of different sizes to explore the influence of the above parameters H, b, and c on the insulation performance and structural strength of the battery.

[0074] The withstand voltage test refers to: using an AC withstand voltage tester to load a high voltage (for example, the high voltage may be 1500V) between the battery housing 100 and the first plastic part 200 for 2 seconds, and detecting the leakage current value. When the leakage current value is less than 2mA and the first plastic part 200 is not broken down, the insulation performance of the battery is good.

[0075] The thrust test refers to: fixing the battery housing 100 and applying a thrust toward the battery housing 100 to the first plastic part 200. When the thrust applied to the first plastic part 200 is greater than 1200N, and the deformation of the battery housing 100 in the thrust direction is less than 0.5mm, the structural strength of the battery is high and meets the product requirements.

[0076] The detailed size parameters of the battery and the test results are shown in Table 1 below.

[0077] Table 1

[0078] H / mm bmm c / mm result Sample 1 2.0 -2.0 2.0 bad Sample 2 2.0 0.5 —0.5 bad Sample 3 2.0 —1.0 0 Good Treason Sample 4 2.0 0.6 1.0 Good Treason Sample 5 2.0 0.2 2.0 good Sample 6 2.0 0 3.0 good Sample 7 2.0 0.3 4.0 good Sample 8 2.0 0.8 5.0 Good Treason Sample 9 2.0 1.0 6.0 good Sample 10 2.0 0.5 7.0 good Sample 11 2.0 -0.4 8.0 good Sample 12 2.0 —0.7 9.0 good Sample 13 2.0 0.1 10.0 good Sample 14 1.0 0 3.0 Good Treason Sample 15 3.0 0.5 3.0 good Sample 16 2.0 0.5 12.0 bad Sample 17 2.0 1.3 3.0 bad

[0079] In sample 1, the value of b is -2.0mm, the value of H is 2.0mm, and the value of b is less than the minimum value of -1mm≤b≤0.5H. At this time, the end surface of the overlapping portion 220 that is away from the second plastic part 300 exceeds the end surface of the top wall 110 that is away from the second plastic part 300 too much, which affects the height design of the pole along the first direction, is not conducive to improving the energy density of the battery, is not recommended for use, and the battery product is defective.

[0080] In sample 2, the value of c is -0.5mm, which is less than the minimum value of 0mm≤c≤10mm. Other parameters H and b meet their corresponding size range limits. At this time, the insulation performance between the first plastic part 200 and the top wall 110 cannot be guaranteed, the voltage test fails, and there is a risk of voltage failure. It is not recommended for use, and the battery product is defective.

[0081] In Sample 3, Sample 4, Sample 5, Sample 6, Sample 7, Sample 8, Sample 9, Sample 10, Sample 11, Sample 12, Sample 13, Sample 14 and Sample 15, the values ​​of parameters H, b, and c all meet their corresponding size range limits. At this time, the insulation performance between the first plastic part 200 and the top wall 110 is good, the pressure test is passed, and the structural strength of the battery housing 100 is high, and the thrust test is passed. It is recommended for use and the battery product is good.

[0082] In sample 16, the value of c is 12.0mm, and the value of c is greater than the maximum value of 0mm≤c≤10mm. Other parameters H and b meet their corresponding size range limits. At this time, the insulation performance between the first plastic part 200 and the top wall 110 is good, and the voltage test is passed. However, the width of the overlapping portion 220 of the first plastic part 200 is large, and the material used for the first plastic part 200 and the pole is increased, resulting in a high cost. It is not recommended for use, and the battery product is defective.

[0083] In sample 17, the value of b is 1.3mm, the value of H is 2.0mm, and the value of b is greater than 0.5H, which does not meet the size limit of -1mm≤b≤0.5H. At this time, the depth of the groove 112 on the top wall 110 is large, the structural strength of the battery casing 100 is low, and the thrust test fails. It is not recommended for use and the battery product is defective.

[0084] Optionally, continue to see Figure 2 and Figure 3 In this embodiment, two electrode groups are provided in the battery housing 100. Figure 2 , Figure 3 A positive electrode ear and a negative electrode ear are respectively provided at both ends of the top wall 110 along the second direction ( Figure 2 , Figure 3 The two ends of the first plastic parts 200 (in the X-axis direction shown in the figure), the poles on the side of the two first plastic parts 200 away from the top wall 110 are respectively a positive pole and a negative pole, and the first plastic part body 210 of each first plastic part 200 is provided with two first through holes 211, and the two first through holes 211 are arranged at intervals along the third direction (the third direction is Figure 2 , Figure 3 The second plastic part 300 is provided with one, and two second through holes 311 are respectively provided at both ends of the second plastic part 300 along the second direction, that is, there are four second through holes 311 in total, and the first through hole 211, the second through hole 311 and the first mounting hole 111 correspond one to one. The positive pole ear of each pole group passes through a second through hole 311, a first mounting hole 111 and a first through hole 211 and is connected to the positive pole column, and the negative pole ear of each pole group passes through the second through hole 311, the first mounting hole 111 and the first through hole 211 at the other end of the second plastic part 300 along the second direction and is connected to the negative pole column. In this way, the positive pole ear and the negative pole ear of the pole group are led out of the battery housing 100 and connected to the pole column on the outside of the battery housing 100, which will not occupy the internal space of the battery housing 100 (that is, the mounting cavity), the space utilization rate is high, the volume of the pole group is increased, and the energy density of the battery is high.

[0085] See also Figure 2 and Fig.10 The first plastic body 210 is provided with a first flange 230 and a connecting rib 240 on the side away from the second plastic body 300. The first flange 230 is arranged in the circumference of the first through hole 211 and extends in the direction away from the top wall 110. There are two first flanges 230 and two connecting ribs 240. Both ends of each connecting rib 240 are connected to a first flange 230. Thus, the first flange 230, the connecting rib 240 and the first plastic body 210 form a mounting groove 241, and at least part of the pole is embedded in the mounting groove 241. In this way, the size of the battery housing assembly along the first direction is further reduced, the space utilization rate is improved, and the energy density is large. Optionally, the first flange 230 is annular and surrounds the outside of the first through hole 211.

[0086] See also Figure 2 , Fig.13 and Fig.14The second plastic part 300 includes a second plastic part body 310 and a second flange 320. The four second through holes 311 are all arranged on the second plastic part body 310 and are located at both ends of the second plastic part body 310 along the second direction. Two second through holes 311 are arranged at each end of the second plastic part body 310. The second flange 320 corresponds to the second through holes 311 one by one, and the second flange 320 is also annular and surrounds the second through holes 311. The second flange 320 is arranged in the circumference of the second through hole 311 and extends in a direction close to the top wall 110. The second flange 320 extends into the first mounting hole 111 and fits with the inner wall of the first mounting hole 111. The second flange 320 insulates the pole ear from the top wall 110 to ensure electrical safety. In addition, through the cooperation between the second flange 320 and the first mounting hole 111, the positioning between the second plastic part 300 and the top wall 110 is also accurate, which helps to improve the assembly accuracy of the battery housing assembly.

[0087] Alternatively, see Figure 2 and Figure 3 The battery housing assembly in this embodiment further includes an explosion-proof valve 400. A second mounting hole 115 is provided on the top wall 110, and the explosion-proof valve 400 is arranged in the second mounting hole 115; a vent hole 340 is provided on the second plastic body 310 at a position corresponding to the second mounting hole 115, and a vent hole 340 is provided along the first direction ( Figure 2 , Figure 3 The projection of the vent hole 340 on the top wall 110 (in the Z-axis direction shown in the figure) coincides with the projection of the explosion-proof valve 400 on the top wall 110. Therefore, when the pressure in the battery housing 100 exceeds the valve opening pressure of the explosion-proof valve 400, high-temperature, high-pressure gas and liquid can be discharged from the battery housing 100 through the vent hole 340 and the explosion-proof valve 400, avoiding the risk of explosion and having high safety. In addition, criss-crossing support ribs 116 are also provided in the second mounting hole 115, and the structural strength of the battery housing 100 at the second mounting hole 115 can be improved by the support ribs 116. Furthermore, a plurality of vent holes 340 on the second plastic body 310 can be arranged at intervals to increase the flow area, so that high-temperature, high-pressure gas and liquid can be discharged quickly and circulate smoothly.

[0088] Furthermore, in this embodiment, the two first plastic parts 200 and the one second plastic part 300 are separately provided, and each part is separately injection molded. In other embodiments, the two first plastic parts 200 and the one second plastic part 300 may also be an integrated structure, and are directly injection molded on the top wall 110. It should be noted that in this solution, the two first plastic parts 200 and the one second plastic part 300 are not easy to be removed from the top wall 110.

[0089] Optionally, in some embodiments, a first injection hole 117 is further provided on the top wall 110, and a second injection hole 350 is provided on the second plastic body 310 at a position corresponding to the first injection hole 117. Along the first direction, the projection of the first injection hole 117 on the top wall 110 coincides with the projection of the second injection hole 350 on the top wall 110. Electrolyte can be injected into the mounting cavity of the battery housing 100 through the first injection hole 117 and the second injection hole 350 so that the electrode group can be immersed in the electrolyte. After the injection is completed, an injection plug can be installed in the first injection hole 117 and / or the second injection hole 350 to seal the first injection hole 117 and / or the second injection hole 350 to prevent leakage of the electrolyte. Exemplarily, the injection plug is made of a material with elastic deformation ability such as rubber.

[0090] This embodiment also provides a battery, including a bottom plate, a pole group, and the above-mentioned battery housing assembly, wherein the bottom plate is connected to the opening 121 of the battery housing 100 to encapsulate the pole group in the mounting cavity of the battery housing 100. The pole lugs of the pole group can be led out through the battery housing assembly, and the poles outside the battery housing 100 are connected to the external circuit so that the pole group can supply power to the external circuit or store energy. By adopting the above-mentioned battery housing assembly, the space utilization rate inside the battery housing 100 is high, the volume of the pole group is increased, and the energy density of the battery is high.

[0091] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A battery housing assembly, characterized in that: include: A battery housing, wherein the interior is hollow to form a mounting cavity, one side of the battery housing has an opening communicating with the mounting cavity, the electrode group is loaded into the mounting cavity through the opening, and a first mounting hole is provided on one wall of the battery housing; A first plastic part, disposed outside the mounting cavity and connected by hot melt to the wall provided with the first mounting hole, wherein the first plastic part is provided with a first through hole; A second plastic part is disposed in the installation cavity and is connected to the wall provided with the first installation hole by heat melting, and a second through hole is provided on the second plastic part; The pole is located on a side of the first plastic part away from the battery housing, and the pole lug of the pole group is connected to the pole after passing through the second through hole, the first mounting hole and the first through hole.

2. The battery housing assembly according to claim 1, characterized in that: The battery housing comprises a top wall and a peripheral side wall, the top wall and the peripheral side wall are arranged to form the mounting cavity, and the top wall is provided with the first mounting hole.

3. The battery housing assembly according to claim 2, characterized in that: One of the first plastic part and the top wall is provided with a first melting column, and the other of the first plastic part and the top wall is provided with a first fixing groove, and the first melting column is inserted and fixed in the first fixing groove by melting; And / or, one of the second plastic part and the top wall is provided with a second melting column, and the other of the second plastic part and the top wall is provided with a second fixing groove, and the second melting column is inserted and fixed in the second fixing groove by melting.

4. The battery housing assembly according to claim 3, characterized in that: The cross-sectional shape of the first fixing groove matches the cross-sectional shape of the first melting column, and the cross-sectional shape of the first melting column is one of a circle, a waist shape and a polygon; And / or, the shape of the cross section of the second fixing groove matches the shape of the cross section of the second melting column, and the shape of the cross section of the second melting column is one of a circle, a waist shape and a polygon.

5. The battery housing assembly according to claim 3, characterized in that: A first overflow groove is recessed on the groove wall of the first fixed groove; And / or, a second overflow groove is recessed on the groove wall of the second fixing groove.

6. The battery housing assembly according to claim 5, characterized in that: The first fixing groove is one of a straight groove, a trapezoidal groove and a stepped groove; And / or, the first overflow groove is one of a straight groove, a trapezoidal groove and a stepped groove; And / or, the second fixing groove is one of a straight groove, a trapezoidal groove and a stepped groove; And / or, the second overflow groove is one of a straight groove, a trapezoidal groove and a stepped groove.

7. The battery housing assembly according to claim 2, characterized in that: The first plastic part comprises a first plastic part body, the first through hole is arranged in the first plastic part body, a lap portion is arranged in the circumference of the first plastic part body, a sink groove is arranged on the end surface of the top wall facing away from the second plastic part, the lap portion is embedded in the sink groove and fits with the bottom wall of the sink groove; Wherein, along the first direction, the thickness of the top wall is H, and the distance between the end surface of the overlapping portion facing away from the second plastic part and the end surface of the top wall facing away from the second plastic part is b; The value range of b satisfies: -1mm≤b≤0.5H, 1mm≤H≤3mm; and / or, along the second direction, the width of the overlap portion is c; The value range of c satisfies: 0mm≤c≤10mm.

8. The battery housing assembly according to claim 7, characterized in that: A first flange and a connecting rib are provided on the side of the first plastic part body facing away from the second plastic part. The first flange is arranged in the circumference of the first through hole. The first flange, the connecting rib and the first plastic part body form a mounting groove. At least part of the pole is embedded in the mounting groove.

9. The battery housing assembly according to claim 1, characterized in that: The second plastic part includes a second plastic part body and a second flange. The second through hole is arranged in the second plastic part body. The second flange is arranged in the circumference of the second through hole. The second flange extends into the first mounting hole and fits with the inner wall of the first mounting hole.

10. A battery, characterized in that: The invention comprises a bottom plate, a pole group, and a battery housing assembly according to any one of claims 1 to 9, wherein the bottom plate is connected to an opening of the battery housing, and the pole group is encapsulated in a mounting cavity of the battery housing.

Images