Single battery and battery pack

Abstract

The invention discloses a single battery and a battery pack, and belongs to the technical field of batteries, the single battery comprises: a shell having an accommodating cavity; the naked battery cell is arranged in the accommodating cavity, and the naked battery cell comprises an arc-shaped side surface; the supporting piece is located between the arc-shaped side face and the shell and connected with the arc-shaped side face and the shell, the supporting piece is provided with a supporting groove formed towards the naked battery cell, the arc-shaped side face is embedded in the supporting groove, and at least part of the arc-shaped side face is attached to the inner wall of the supporting groove. The supporting piece is arranged between the arc-shaped side face of the naked battery cell and the shell, and at least part of the arc-shaped side face is attached to the inner wall of the supporting groove, so that when the naked battery cell deforms, the supporting piece can play a certain role in restraining the naked battery cell, deformation of the naked battery cell is restrained, and the distance between a positive plate and a negative plate on the naked battery cell can be prevented from being increased; and the phenomenon of lithium separation between the positive plate and the negative plate is avoided.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to a single cell and a battery pack. Background Art

[0002] In the battery, the bare cell can be formed by winding the positive and negative electrode sheets and the isolation layer together. After the bare cell is wound, its two sides are arc-shaped structures, and the bare cell is set inside the battery casing. During the use of the battery, the bare cell is prone to deformation, which increases the distance between the electrode sheets, resulting in lithium deposition between the electrode sheets. Summary of the invention

[0003] Purpose of the invention: The embodiment of the present application provides a single cell battery, aiming to overcome the technical problem that bare cells are prone to deformation, which increases the distance between pole pieces. Another purpose of the present application is to provide a battery pack.

[0004] Technical solution: A single cell battery according to an embodiment of the present application includes:

[0005] A housing having a receiving cavity;

[0006] A bare battery cell is disposed in the accommodating cavity, wherein the bare battery cell comprises an arc-shaped side surface;

[0007] A support member is located between the arc-shaped side surface and the shell, and is connected to the arc-shaped side surface and the shell respectively, the support member has a support groove opened toward the bare battery cell, the arc-shaped side surface is embedded in the support groove, and at least a portion of the arc-shaped side surface is arranged in contact with the inner wall of the support groove;

[0008] The single cell satisfies: 0.5≤S1 / S≤1;

[0009] Wherein, S is the total area of ​​the arc-shaped side surface, and S1 is the area where the arc-shaped side surface fits with the inner wall of the support groove.

[0010] In some embodiments, there is a gap between the portion of the arc-shaped side surface and the inner wall of the supporting groove, and the maximum size of the gap is L, satisfying: L≤1mm.

[0011] In some embodiments, the support member includes a first filling portion and a second filling portion arranged along the width direction X of the shell, the first filling portion is respectively connected to the shell and the curved side, the second filling portion is respectively connected to the shell and the curved side, and the first filling portion and the second filling portion enclose to form the support groove.

[0012] In some embodiments, the single cell includes a plurality of bare cells, and the plurality of bare cells are arranged along the width direction X of the shell. The support member has a plurality of support grooves arranged along the width direction X of the shell, and each of the arc-shaped side surfaces is embedded in one of the support grooves.

[0013] In some embodiments, the support member comprises:

[0014] The transition surface is located between the inner walls of two adjacent support grooves and is respectively connected to the inner walls of the two adjacent support grooves; the transition surface is an arc-shaped surface.

[0015] In some embodiments, the support member comprises:

[0016] A transition surface, located between the inner walls of two adjacent support grooves, and respectively connected to the inner walls of the two adjacent support grooves;

[0017] The transition surface includes a first connecting surface and a second connecting surface that are connected to each other, the first connecting surface is connected to one of the inner walls of the two adjacent support grooves and is arranged toward one of the two adjacent bare battery cells, the second connecting surface is connected to the other of the inner walls of the two adjacent support grooves and is arranged toward the other of the two adjacent bare battery cells, and the connection between the first connecting surface and the second connecting surface is spaced apart from the two adjacent bare battery cells.

[0018] In some embodiments, the support member includes a first side surface and a second side surface, and the first side surface and the second side surface are spaced apart along a width direction X of the housing;

[0019] The support member includes a first overlapping surface and a second overlapping surface, the first overlapping surface is located between the first side surface and the inner wall of the support groove, and is respectively connected to the first side surface and the inner wall of the support groove, the first overlapping surface is arranged toward the bare battery cell, the second overlapping surface is located between the second side surface and the inner wall of the support groove, and is respectively connected to the second side surface and the inner wall of the support groove, and the second overlapping surface is arranged toward the bare battery cell; the first overlapping surface and the second overlapping surface are arc-shaped surfaces or inclined surfaces.

[0020] In some embodiments, the support member includes a first side surface and a second side surface, and the first side surface and the second side surface are arranged at intervals along the width direction X of the shell; the support member includes a large surface arranged away from the inner wall of the support groove;

[0021] The support member includes a third overlapping surface and a fourth overlapping surface, the third overlapping surface is located between the first side surface and the large surface, and is respectively connected to the first side surface and the large surface, and the third overlapping surface is an arcuate surface or an inclined surface intersecting the first side surface and the large surface; the fourth overlapping surface is located between the second side surface and the large surface, and is respectively connected to the second side surface and the large surface, and the fourth overlapping surface is an arcuate surface or an inclined surface intersecting the second side surface and the large surface.

[0022] In some embodiments, the support member comprises:

[0023] A main body part is located between the arc-shaped side surface and the shell, and is connected to the arc-shaped side surface and the shell respectively, and the supporting groove is formed on the main body part; the main body part has a hollow groove communicating with the accommodating cavity, and the hollow groove is arranged away from the bare battery cell;

[0024] At least one reinforcement portion is located in the hollow groove and connected to the main body, and an extension direction of at least a portion of the reinforcement portion is the same as or intersects with a width direction of the shell.

[0025] A battery pack comprises any one of the above-mentioned single cells.

[0026] Beneficial effects: The single cell battery of the embodiment of the present application comprises: a shell having a accommodating cavity; a bare cell arranged in the accommodating cavity, the bare cell comprising an arc-shaped side surface; a support member located between the arc-shaped side surface and the shell, and respectively connected to the arc-shaped side surface and the shell, the support member having a support groove opened toward the bare cell, the arc-shaped side surface being embedded in the support groove, and at least a portion of the arc-shaped side surface being arranged in contact with the inner wall of the support groove; the single cell battery satisfies: 0.5≤S1 / S≤1; wherein S is the total area of ​​the arc-shaped side surface, and S1 is the area in contact with the inner wall of the support groove. The support member is arranged between the arc-shaped side surface of the bare cell and the shell, and at least a portion of the arc-shaped side surface is in contact with the inner wall of the support groove. When the bare cell is deformed, the support member can play a certain restraining role on it, suppressing the deformation of the bare cell, thereby preventing the distance between the positive and negative electrode sheets on the bare cell from increasing, and avoiding the phenomenon of lithium deposition between the positive and negative electrode sheets. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1This is a schematic diagram of the top view of the single cell structure of the embodiment of the present application, wherein the arc-shaped side portion is in contact with the inner wall of the support groove;

[0029] Figure 2 For the embodiment of this application Figure 1 A partial enlarged view of the middle C area;

[0030] Figure 3 This is a schematic diagram of the top view of the single cell of the embodiment of the present application, wherein the arc-shaped side surface is completely in contact with the inner wall of the support groove;

[0031] Figure 4 A three-dimensional diagram of a support member having a support groove according to an embodiment of the present application;

[0032] Figure 5 It is a schematic diagram of a top view of a single cell according to an embodiment of the present application, wherein the support member includes a first filling portion and a second filling portion;

[0033] Figure 6 It is a three-dimensional diagram of the first filling part and the second filling part of the embodiment of the present application;

[0034] Figure 7 This is a schematic structural diagram of a form of a support member in an embodiment of the present application;

[0035] Figure 8 For the embodiment of this application Figure 7 Enlarged view of area A in the middle;

[0036] Fig. 9 This is a schematic structural diagram of another form of a support member according to an embodiment of the present application;

[0037] Fig.10 For the embodiment of this application Fig. 9 Enlarged view of area B in the middle;

[0038] Fig.11 It is a schematic diagram of the top view of the single cell structure of an embodiment of the present application, wherein the support member has a plurality of support grooves;

[0039] Fig.12 This is a structural schematic diagram of a form of the inner wall connection of two adjacent support grooves in an embodiment of the present application;

[0040] Fig.13 This is a schematic diagram of another structural form of the inner wall connection of two adjacent support grooves in an embodiment of the present application;

[0041] Fig.14 This is a schematic structural diagram of a support member having multiple support grooves according to an embodiment of the present application;

[0042] Fig.15 It is a rear perspective view of a support member of an embodiment of the present application, wherein the support member has a support groove;

[0043] Fig.16 This is a rear perspective view of the second filling portion of the embodiment of the present application;

[0044] Fig.17 It is a rear perspective view of a support member of an embodiment of the present application, wherein the support member has a plurality of support grooves;

[0045] Figure markings: 10-shell; 11-accommodating cavity; 20-bare cell; 21-arc-shaped side; 211-gap; 30-support member; 31-support groove; 311-inner wall; 32-first filling part; 33-second filling part; 34-transition surface; 341-first sub-surface; 342-second sub-surface; 35-first side surface; 36-second side surface; 37-first lap surface; 38-second lap surface; 39-large surface; 310-third lap surface; 320-fourth lap surface; 330-hollow groove; 340-main body; 350-reinforcement part; X-width direction. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0047] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "plurality" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined.

[0048] In a battery, a bare cell can be formed by winding the positive and negative electrodes and the isolation layer together. After the bare cell is wound and formed, its two sides are arc-shaped structures. When the bare cell is set inside the battery shell, there is a certain gap between the arc-shaped structure on it and the shell. During the use of the battery, the bare cell is prone to deformation. At the position of the arc-shaped structure, since there is no constraint of the shell and the distance between the shell is large, it is easier to deform here. The deformation of the bare cell will increase the distance between the positive and negative electrodes on it, thereby causing lithium precipitation between the positive and negative electrodes at the position of the arc-shaped structure (lithium precipitation refers to the phenomenon that lithium ions react in the electrolyte to form solid lithium metal or lithium alloy during the battery charging and discharging process). This phenomenon will cause the performance of the battery to decline and even cause safety problems.

[0049] In view of this, an embodiment of the present application provides a single cell to overcome at least one of the above technical problems.

[0050] See also Figure 1 , Figure 2 , Figure 3 and Figure 4 In the embodiment of the present application, the single cell includes a shell 10 , a bare cell 20 and a support member 30 .

[0051] The shell 10 has a accommodating cavity 11, and other structural components of the battery can be arranged inside the accommodating cavity 11. The shell 10 can be arranged in coordination with the cover plate assembly of the battery to protect the structural components installed inside the accommodating cavity 11. The bare cell 20 is formed by winding the positive and negative electrodes and the isolation layer together, and is arranged in the accommodating cavity 11. The bare cell 20 includes an arcuate side surface 21, and there are two arcuate side surfaces 21, which are respectively located on both sides of the bare cell 20. At the same time, there is a certain space between each arcuate side surface 21 and the shell 10, and the support member 30 is arranged between the arcuate side surface 21 and the shell 10, and is respectively connected to the arcuate side surface 21 and the shell 10. The support member 30 has a support groove 31 opened toward the bare cell 20, and the arcuate side surface 21 is embedded in the support groove 31, and at least a part of the arcuate side surface 21 is arranged in contact with the inner wall 311 of the support groove 31. It can be understood that the support member 30 is arranged between the arc-shaped side surface 21 of the bare cell 20 and the shell 10 to fill the space between the arc-shaped side surface 21 and the shell 10. The support member 30 is provided with a support groove 31 toward the arc-shaped side surface 21, so that the arc-shaped side surface 21 of the bare cell 20 can be embedded in the support groove 31. This slotted arrangement can make the support member 30 better fit the shape of the space between the arc-shaped side surface 21 and the shell 10, so that the arc-shaped side surface 21 is more fully in contact with the inner wall 311 of the support groove 31, thereby improving the filling effect of the support member 30. At least part of the arc-shaped side surface 21 is in contact with the inner wall 311 of the support groove 31, that is, part of the arc-shaped side surface 21 is in contact with the inner wall 311, or the entire arc-shaped side surface 21 is in contact with the inner wall 311. This arrangement can meet the need to constrain bare cells 20 of different specifications and sizes, improve the applicable scope of the support member 30, and there is no need to set a support member 30 for each bare cell 20 of each specification and size. The shape of the inner wall 311 of the support groove 31 is not limited. Preferably, the inner wall 311 can be arc-shaped, which is conducive to fitting with the arc-shaped side surface 21, and improving the restraining effect of the support member 30 on the bare battery cell 20. When the bare battery cell 20 is deformed, the support member 30 can play a certain restraining role on it, suppressing the deformation of the bare battery cell 20, thereby preventing the distance between the positive and negative electrode sheets at or near the arc-shaped side surface 21 on the bare battery cell 20 from increasing, avoiding the phenomenon of lithium deposition between the positive and negative electrode sheets, avoiding safety problems, and extending the service life of the battery.

[0052] The single cell satisfies: 0.5≤S1 / S≤1; wherein S is the total area of ​​the arc-shaped side surface 21, and S1 is the area where the arc-shaped side surface 21 and the inner wall 311 of the support groove 31 are bonded. It can be understood that when the arc-shaped side surface 21 and the inner wall 311 of the support groove 31 are bonded, the ratio of the bonded area S1 to the total area of ​​the arc-shaped side surface 21 is in the range of 0.5 to 1, and can be any value among 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, or a range value between any two values. When the ratio between the two is in the range of 0.5 to 1, the support member 30 can provide a better restraining effect on the bare cell 20, and can prevent the bare cell 20 from being deformed to a large extent, and avoid the phenomenon of lithium deposition between the positive and negative electrodes at or near the arc-shaped side surface 21.

[0053] The values ​​of S1 and S can be measured by an optical 3D scanner (scanning the surface and recording a large amount of point cloud data, then using this data to reconstruct the geometric shape of the surface and calculate the area of ​​the surface), a surface measuring instrument (combining optics, laser or other measurement technology, which can directly measure the shape and size of the surface and calculate the area of ​​the surface). The test results of the embodiments and comparative examples are shown in the following table:

[0054]

[0055]

[0056] According to the test data in the above table, when 0.5≤S1 / S≤1 is satisfied, the battery is subjected to a cycle test, and the test result indicates that no lithium deposition occurs between the pole pieces at the position of the curved side surface 21. When 0.5≤S1 / S≤1 is not satisfied, the battery is subjected to a cycle test, and the test result indicates that lithium deposition occurs between the pole pieces at the position of the curved side surface 21. This indicates that satisfying the range of 0.5≤S1 / S≤1 can enable the support member 30 to provide a good restraint effect on the bare battery cell 20, avoid increasing the distance between the positive and negative pole pieces at the position of the curved side surface 21, and prevent lithium deposition between the pole pieces, thereby reducing the safety risk during battery use and increasing the battery life.

[0057] See also Figure 1 , Figure 2 and Figure 3In combination with the above embodiments, in some embodiments, there is a gap 211 between part of the arcuate side surface 21 and the inner wall 311 of the support groove 31, and the maximum size of the gap 211 is L, which satisfies: L≤1mm. It can be understood that when a part of the arcuate side surface 21 is fitted with the inner wall 311 of the support groove 31, there will be a gap 211 between the other part of the arcuate side surface 21 and the inner wall 311 of the support groove 31, and the maximum size L of the gap 211 in the radial direction of the arcuate side surface 21 must meet the requirement of being less than 1mm (L can be measured by tools such as vernier calipers and laser rangefinders). Within this range, the support member 30 can also provide a better restraint effect on the bare battery cell 20, which can prevent the bare battery cell 20 from being deformed to a certain extent, and avoid the phenomenon of lithium deposition in the battery. At the same time, the existence of the gap 211 is caused by the different curvatures of the curved side surface 21 and the inner wall 311 of the support groove 31. Different curvatures facilitate the restraint of different bare cells 20, thereby improving the applicability of the support member 30, and only needs to meet the range requirements of 0.5≤S1 / S≤1 and L≤1mm.

[0058] See also Figure 5 and Figure 6In combination with the above embodiments, in some embodiments, the support member 30 includes a first filling portion 32 and a second filling portion 33 arranged along the width direction X of the housing 10. The first filling portion 32 and the second filling portion 33 may be arranged at intervals in the width direction X, or may be arranged in connection in the width direction X. The first filling portion 32 and the second filling portion 33 are combined to form the support member 30. The first filling portion 32 is respectively connected to the housing 10 and the arc-shaped side surface 21, and the second filling portion 33 is respectively connected to the housing 10 and the arc-shaped side surface 21. The first filling portion 32 and the second filling portion 33 enclose a support groove 31. It can be understood that the first filling part 32 and the second filling part 33 both have a groove body on the side facing the curved side surface 21. The groove body on the first filling part 32 and the groove body of the second filling part 33 can enclose to form a support groove 31. The groove walls of these two groove bodies are equivalent to the inner wall 311 of the support groove 31. At least part of the curved side surface 21 is fitted with the groove wall of the corresponding groove body, so that the first filling part 32 and the second filling part 33 can play a certain restraining role on the bare battery cell 20, thereby preventing it from deforming and avoiding the increase in the distance between the positive and negative electrodes at or near the curved side surface 21 on the bare battery cell 20. The bare battery cell 20 is restrained by the first filling part 32 and the second filling part 33. Since the individual volumes of the two are smaller than the entire support member 30, it is more convenient to install the first filling part 32 and the second filling part 33 between the shell 10 and the curved side surface 21 respectively, which reduces the difficulty of installation compared to installing a support member 30 with a larger volume. At the same time, the first filling part 32 and the second filling part 33 are mirror-image structures and are identical in structure. During production and processing, only one of them needs to be processed. Compared with processing the support member 30, processing the filling part alone is simpler and can improve the efficiency of production and processing.

[0059] See also Fig.11 and Fig.14 In combination with the above embodiments, in some embodiments, the single battery includes a plurality of bare cells 20, and the plurality of bare cells 20 are arranged along the width direction X of the shell 10. The support member 30 has a plurality of support grooves 31 arranged along the width direction X of the shell 10, and each arc-shaped side surface 21 is embedded in a support groove 31. It can be understood that two or more bare cells 20 can be arranged inside the shell 10 along the width direction X at the same time, and the arc-shaped side surfaces 21 of these bare cells 20 are constrained. The support member 30 can be provided with the same number of support grooves 31 as the bare cells 20, and the corresponding arc-shaped side surfaces 21 are constrained by the inner wall 311 of each support groove 31. The support member 30 with a plurality of support grooves 31 can meet the requirements of constraining a plurality of bare cells 20, improve the applicable scope of the support member 30, and better meet the use requirements of the battery.

[0060] See also Fig.11 and Fig.12In combination with the above embodiments, in some embodiments, the support member 30 includes a transition surface 34. The transition surface 34 is located between the inner walls 311 of two adjacent support grooves 31, and is respectively connected to the inner walls 311 of the two adjacent support grooves 31; the transition surface 34 is an arc surface. It can be understood that when the support member 30 constrains a plurality of bare cells 20, the inner walls 311 of two adjacent support grooves 31 thereon can be connected through the transition surface 34, and the transition surface 34 is located between two adjacent bare cells 20 and is set as an arc surface. Since the surface of the arc surface is relatively smooth, when the support member 30 and the bare cell 20 are assembled, the transition surface 34 will not cause damage to the bare cell 20. If the bare cell 20 expands during the recycling process and contacts or squeezes the transition surface 34, the transition surface 34 will not cause damage to the bare cell 20, which can reduce the risk of damage and puncture of the bare cell 20 to a certain extent.

[0061] See also Fig.11 and Fig.13 In combination with the above embodiments, in some embodiments, the support member 30 includes a transition surface 34. The transition surface 34 is located between the inner walls 311 of two adjacent support grooves 31, and is respectively connected to the inner walls 311 of the two adjacent support grooves 31. The transition surface 34 includes a first connection surface 341 and a second connection surface 342 that are connected to each other, the first connection surface 341 is connected to one of the inner walls 311 of the two adjacent support grooves 31, and is arranged toward one of the two adjacent bare cells 20, the second connection surface 342 is connected to the other of the inner walls 311 of the two adjacent support grooves 31, and is arranged toward the other of the two adjacent bare cells 20, and the connection between the first connection surface 341 and the second connection surface 342 is spaced from the two adjacent bare cells 20. It can be understood that the transition surface 34 can be configured as a first connection surface 341 and a second connection surface 342 that are connected to each other. The first connection surface 341 and the second connection surface 342 are respectively connected to two adjacent inner walls 311. The first connection surface 341 and the second connection surface 342 can be an arc surface or a plane. The connection between the two is relatively sharp, and the connection is spaced apart from the two adjacent bare cells 20. When the bare cell 20 and the support member 30 are assembled, the bare cell 20 can be prevented from contacting the connection between the two to a certain extent, thereby preventing the connection between the two from causing damage to the bare cell 20. If the bare cell 20 expands during the recycling process, the connection between the first connection surface 341 and the second connection surface 342 has a certain gap with the bare cell 20, providing a certain buffer space for the expansion of the bare cell 20, thereby preventing the bare cell 20 from directly contacting and squeezing the connection between the two when expanding, and also preventing the connection from causing damage to the bare cell 20 to a certain extent, thereby reducing the risk of damage or puncture to the bare cell 20.

[0062] See also Figure 7 , Figure 8 , Fig. 9 , Fig.10 and Fig.14 In combination with the above embodiments, in some embodiments, the support member 30 includes a first side surface 35 and a second side surface 36, and the first side surface 35 and the second side surface 36 are arranged at intervals along the width direction X of the housing 10. It can be understood that the first side surface 35 and the second side surface 36 are surfaces facing the shell wall of the housing 10, and are arranged back to back with each other.

[0063] The support member 30 includes a first lap joint surface 37 and a second lap joint surface 38. The first lap joint surface 37 is located between the first side surface 35 and the inner wall 311 of the support groove 31, and is respectively connected to the first side surface 35 and the inner wall 311 of the support groove 31. The first lap joint surface 37 is arranged toward the bare cell 20. The second lap joint surface 38 is located between the second side surface 36 and the inner wall 311 of the support groove 31, and is respectively connected to the second side surface 36 and the inner wall 311 of the support groove 31. The second lap joint surface 38 is arranged toward the bare cell 20. The first lap joint surface 37 and the second lap joint surface 38 are arcuate surfaces or inclined surfaces. It can be understood that the first side surface 35 is connected to the inner wall 311 of the support groove 31 through the first lap joint surface 37. When the first lap joint surface 37 is an arcuate surface, it is arranged toward the bare cell 20. The arcuate surface is relatively smooth, and when the bare cell 20 is assembled with the support member 30, it will not cause damage to the bare cell 20. When the first lap joint surface 37 is an inclined surface and is disposed toward the bare cell 20, the angle between the first lap joint surface 37 and the first side surface 35 is an acute angle, and the connection between the two is relatively sharp. This arrangement will allow a certain space to exist between the connection between the first lap joint surface 37 and the first side surface 35 and the bare cell 20, and when the bare cell 20 is assembled with the support member 30 or the bare cell 20 expands, the bare cell 20 and the connection between the first lap joint surface 37 and the first side surface 35 can be prevented from contacting to a certain extent, thereby reducing the risk of damage or puncture of the bare cell 20.

[0064] See also Figure 7 , Figure 8 , Fig. 9 and Fig.10 In combination with the above embodiments, in some embodiments, the support member 30 includes a first side surface 35 and a second side surface 36, and the first side surface 35 and the second side surface 36 are arranged at intervals along the width direction X of the housing 10; the support member 30 includes a large surface 39 arranged away from the inner wall 311 of the support groove 31. It can be understood that the first side surface 35 and the second side surface 36 are surfaces facing the housing wall of the housing 10, and are arranged back to back with each other. The large surface 39 is also a surface facing the housing wall of the housing 10, and is arranged back to back with the inner wall 311 of the support groove 31.

[0065] The support member 30 includes a third overlap surface 310 and a fourth overlap surface 320. The third overlap surface 310 is located between the first side surface 35 and the large surface 39, and is connected to the first side surface 35 and the large surface 39 respectively. The third overlap surface 310 is an arcuate surface or an inclined surface intersecting the first side surface 35 and the large surface 39. The fourth overlap surface 320 is located between the second side surface 36 and the large surface 39, and is connected to the second side surface 36 and the large surface 39 respectively. The fourth overlap surface 320 is an arcuate surface or an inclined surface intersecting the second side surface 36 and the large surface 39. It can be understood that the first side surface 35 is connected to the large surface 39 through the third overlap surface 310. The third overlap surface 310 can be an arcuate surface, and the surface of the arcuate surface is relatively smooth. Since it is arranged toward the shell 10, when the third overlap surface 310 contacts the shell 10, the smooth third overlap surface 310 can avoid damage to the shell 10 and prevent interference between the support member 30 and the shell 10. The third lap surface 310 may also be an inclined surface, and the angles between the inclined surface and the first side surface 35 and the large surface 39 are all obtuse angles, which is equivalent to reducing the sharpness of the connection between the first side surface 35 and the large surface 39, and to a certain extent, it can also avoid damage to the shell 10 and prevent interference between the support member 30 and the shell 10. Similarly, the second side surface 36 is connected to the large surface 39 through the fourth lap surface 320, and the fourth lap surface 320 can be an arc surface or an inclined surface, which can also avoid damage to the shell 10 and prevent interference between the support member 30 and the shell 10.

[0066] See also Fig.15 , Fig.16 and Fig.17 In combination with the above embodiments, in some embodiments, the support member 30 includes a main body 340. The main body 340 is located between the arc-shaped side surface 21 and the shell 10, and is respectively connected to the arc-shaped side surface 21 and the shell 10, and the support groove 31 is formed on the main body 340. The main body 340 has a hollow groove 330 connected to the accommodating cavity 11, and the hollow groove 330 is arranged away from the bare battery cell 20. It can be understood that a hollow groove 330 is provided on the main body 340 of the support member 30, and the hollow groove 330 is provided on the side of the main body 340 away from the bare battery cell 20, which does not affect the inner wall 311 of the support groove 31 to constrain the bare battery cell 20. By providing the hollow groove 330, the weight of the support member 30 can be reduced, making the battery setting lighter, and at the same time, the material used for the support member 30 can be reduced, reducing the cost of its production and processing. Furthermore, when injecting electrolyte into the battery, the electrolyte can be filled in the hollow groove 330, and more electrolyte can be injected into the battery so that the electrolyte can fully soak the bare battery cell 20. The first filling part 32 and the second filling part 33 in the above embodiment can also be provided with a hollow groove 330, and the effect is the same as described above.

[0067] See also Fig.15 , Fig.16 and Fig.17 In combination with the above embodiments, in some embodiments, the support member 30 includes a reinforcing portion 350. The reinforcing portion 350 is located in the hollow groove 330 and is connected to the main body 340. It can be understood that the reinforcing portion 350 is provided inside the hollow groove 330 to ensure the use strength of the support member 30, improve the ability to resist deformation, ensure the restraint effect on the bare battery cell 20, and avoid deformation of the support member 30 when the bare battery cell 20 squeezes the support member 30.

[0068] See also Fig.15 , Fig.16 and Fig.17 In combination with the above embodiments, in some embodiments, the support member 30 includes a plurality of reinforcing parts 350, and the plurality of reinforcing parts 350 are all located inside the hollow groove 330. The extension direction of at least part of the reinforcing part 350 is the same as or intersects with the width direction X of the shell 10. It can be understood that a plurality of reinforcing parts 350 can be arranged inside the hollow groove 330, and the plurality of reinforcing parts 350 can be extended along the width direction X of the shell 10, or along a direction intersecting with the width direction X of the shell 10. In short, the reinforcing part 350 can be arranged horizontally, vertically, or inclined, or a part can be arranged horizontally and the other part can be arranged vertically or inclined (the direction of the inclined setting refers to the direction inclined to the horizontal setting). By setting different directions as needed, the easily deformed position of the support member 30 can be well reinforced to avoid deformation at this position, thereby improving the restraining effect of the support member 30 on the bare battery cell 20.

[0069] A battery pack includes any of the above-mentioned single cells, and has all the technical features and beneficial effects of the single cells, which will not be described in detail here.

[0070] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0071] The single cell and battery pack provided in the embodiments of the present application are introduced in detail above, and the principles and implementation methods of the present application are explained by using specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A single cell battery, characterized in that: include: A housing having a receiving cavity; A bare battery cell is disposed in the accommodating cavity, wherein the bare battery cell comprises an arc-shaped side surface; A support member is located between the arc-shaped side surface and the shell, and is connected to the arc-shaped side surface and the shell respectively, the support member has a support groove opened toward the bare battery cell, the arc-shaped side surface is embedded in the support groove, and at least a portion of the arc-shaped side surface is arranged in contact with the inner wall of the support groove; The single cell satisfies: 0.5≤S1 / S≤1; Wherein, S is the total area of ​​the arc-shaped side surface, and S1 is the area where the arc-shaped side surface fits with the inner wall of the support groove.

2. The single cell according to claim 1, characterized in that: There is a gap between the arc-shaped side portion and the inner wall of the supporting groove, and the maximum size of the gap is L, which satisfies: L≤1mm.

3. The single cell according to claim 1, characterized in that: The support member includes a first filling portion and a second filling portion arranged along the width direction of the shell, the first filling portion is respectively connected to the shell and the curved side surface, the second filling portion is respectively connected to the shell and the curved side surface, and the first filling portion and the second filling portion enclose the support groove.

4. The single cell according to claim 1, characterized in that: The single battery comprises a plurality of bare cells arranged along the width direction of the shell, the support member comprises a plurality of support grooves arranged along the width direction of the shell, and each of the arc-shaped side surfaces is embedded in one of the support grooves.

5. The single cell according to claim 4, characterized in that: The support member comprises: The transition surface is located between the inner walls of two adjacent support grooves and is respectively connected to the inner walls of the two adjacent support grooves; the transition surface is an arc-shaped surface.

6. The single cell according to claim 4, characterized in that: The support member comprises: A transition surface, located between the inner walls of two adjacent support grooves, and respectively connected to the inner walls of the two adjacent support grooves; The transition surface includes a first connecting surface and a second connecting surface that are connected to each other, the first connecting surface is connected to one of the inner walls of the two adjacent support grooves and is arranged toward one of the two adjacent bare battery cells, the second connecting surface is connected to the other of the inner walls of the two adjacent support grooves and is arranged toward the other of the two adjacent bare battery cells, and the connection between the first connecting surface and the second connecting surface is spaced apart from the two adjacent bare battery cells.

7. The single cell according to claim 1 or 4, characterized in that: The support member comprises a first side surface and a second side surface, wherein the first side surface and the second side surface are arranged at intervals along the width direction of the housing; The support member includes a first overlapping surface and a second overlapping surface, the first overlapping surface is located between the first side surface and the inner wall of the support groove, and is respectively connected to the first side surface and the inner wall of the support groove, the first overlapping surface is arranged toward the bare battery cell, the second overlapping surface is located between the second side surface and the inner wall of the support groove, and is respectively connected to the second side surface and the inner wall of the support groove, and the second overlapping surface is arranged toward the bare battery cell; the first overlapping surface and the second overlapping surface are arc-shaped surfaces or inclined surfaces.

8. The single cell according to claim 1 or 4, characterized in that: The support member includes a first side surface and a second side surface, and the first side surface and the second side surface are arranged at intervals along the width direction of the shell; the support member includes a large surface arranged away from the inner wall of the support groove; The support member includes a third overlapping surface and a fourth overlapping surface, the third overlapping surface is located between the first side surface and the large surface, and is respectively connected to the first side surface and the large surface, and the third overlapping surface is an arcuate surface or an inclined surface intersecting the first side surface and the large surface; the fourth overlapping surface is located between the second side surface and the large surface, and is respectively connected to the second side surface and the large surface, and the fourth overlapping surface is an arcuate surface or an inclined surface intersecting the second side surface and the large surface.

9. The single cell according to claim 1, characterized in that: The support member comprises: A main body part is located between the arc-shaped side surface and the shell, and is connected to the arc-shaped side surface and the shell respectively, and the supporting groove is formed on the main body part; the main body part has a hollow groove communicating with the accommodating cavity, and the hollow groove is arranged away from the bare battery cell; At least one reinforcement portion is located in the hollow groove and connected to the main body, and an extension direction of at least a portion of the reinforcement portion is the same as or intersects with a width direction of the shell.

10. A battery pack, characterized in that: The invention comprises a single cell according to any one of claims 1 to 9.

Images