Single battery and battery pack

Abstract

The utility model discloses a single battery and a battery pack, the single battery has a first direction and a second direction which are intersected, and the single battery comprises a shell with an accommodating cavity, and a roll core, a limiting piece and a stabilizing piece which are arranged in the accommodating cavity. Wherein the shell comprises a shell body and a cover body, the shell body is provided with a containing cavity, and the cover body is connected to one side of the shell body in the first direction and covers and seals the containing cavity; arc-shaped surfaces are arranged at two ends of the roll core in the second direction; in the second direction, at least one limiting piece is arranged at each of the two ends of the roll core; wherein the limiting piece is provided with a limiting surface facing the arc-shaped surface, and the limiting surface is in contact with at least part of the arc-shaped surface in an attached mode; in the second direction, the two ends of the stabilizing piece are connected with the limiting pieces located at the two ends of the roll core respectively. According to the scheme, the stabilizing piece restrains the relative positions of the two limiting pieces, and the limiting pieces abut against the arc-shaped surfaces at the two ends of the roll core in an attached mode through the limiting surfaces, so that the positive plate and the negative plate in the roll core are tightly attached on the arc-shaped surfaces, and lithium precipitation is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of secondary batteries, in particular to a single battery and a battery pack. BACKGROUND

[0002] As a core component in the field of new energy technology, the performance of a battery affects the performance of an electrical equipment. The cell inside the battery is generally formed by winding or stacking a positive sheet, a separator and a negative sheet, and the one formed by winding is also called a winding core.

[0003] After winding and hot pressing, the winding core is formed, and the formed winding core has a flat part and an arc part located at opposite ends of the flat part. It is found that the part of the negative sheet and the positive sheet located in the arc part is not tightly fitted due to stress problems, that is, there is a gap between the positive sheet and the negative sheet in the arc part, which makes it difficult for lithium ions to smoothly embed into the negative sheet, and further leads to lithium precipitation of the negative sheet. CONTENT OF THE UTILITY MODEL

[0004] The present application provides a single battery and a battery pack to solve the technical problem of lithium precipitation of the negative sheet in the winding core.

[0005] A single battery has a first direction and a second direction intersecting each other, and the single battery comprises: a shell comprising a shell body and a cover body, the shell body having a receiving cavity, and the cover body being connected to one side of the shell body along the first direction and sealing the receiving cavity; at least one winding core arranged in the receiving cavity, the winding core having an arc surface at both ends in the second direction; a limiting piece arranged in the receiving cavity, the limiting piece being provided with a plurality of limiting pieces, and in the second direction, at least one limiting piece is arranged at each end of the winding core; wherein the limiting piece has a limiting surface facing the arc surface, and the limiting surface is in contact with at least part of the arc surface; and a stabilizing piece arranged in the receiving cavity, and in the second direction, both ends of the stabilizing piece are connected with the limiting pieces located at both ends of the winding core.

[0006] In the embodiment of the present application, the stabilizing piece is connected between the two limiting pieces to constrain the relative position of the two limiting pieces in the second direction, which enables the limiting piece to abut against the arc surface at both ends of the winding core through the limiting surface, thereby limiting the arc surface part of the winding core, so that the positive sheet and the negative sheet in the winding core can be tightly fitted at the corner where the arc surface is located, ensuring that lithium ions smoothly detach or embed between the positive sheet and the negative sheet, so as to reduce lithium precipitation. Moreover, since the stabilizing piece connects the two limiting pieces, the stabilizing piece and the limiting piece form a reliable and stable overall structure, reducing the relative displacement between the limiting piece and the winding core, which makes the relative position between the limiting piece and the winding core more stable, thereby improving the accuracy of the limiting piece in limiting the arc surface of the winding core, to further reduce lithium precipitation.

[0007] As one of the optional embodiments of the present application, the stabilizing piece is arranged on the side of the winding core away from the cover, and the stabilizing piece has a bearing surface facing the winding core, and the winding core is placed on the bearing surface.

[0008] In the embodiments of the present application, the stabilizing piece and the limiting piece jointly form a support structure for bearing and limiting the winding core, and the winding core is limited from the bottom surface and both ends in the second direction, so that the limiting of the winding core is more stable and reliable. It can be understood that the limiting piece can be better limited by the abutment of the limiting surface and the arc surface, and if the position between the limiting piece and the winding core deviates, the abutment between the limiting surface and the arc surface will not be tight enough, thereby losing the limiting effect. However, the embodiments of the present application can effectively ensure the stability of the position between the limiting piece and the winding core through the structural design of the stabilizing piece and the limiting piece.

[0009] As one of the optional embodiments of the present application, the limiting piece includes an arc plate connected to the bearing surface, the arc plate extends along the first direction, and the surface of the arc plate facing the arc surface is a limiting surface.

[0010] In the embodiments of the present application, a specific structure of the limiting piece is disclosed, and the arc plate is arranged to realize abutment with the arc surface while reducing material and space occupation, thereby ensuring the energy density of the battery.

[0011] As one of the optional embodiments of the present application, a third direction is further provided, the first direction, the second direction and the third direction intersect with each other, a plurality of winding cores are provided, and the plurality of winding cores are stacked along the third direction; the limiting piece further includes a support plate connected to the side of the arc plate away from the winding core, and the arc plate is arranged one by one corresponding to the winding core.

[0012] In the embodiments of the present application, when the winding core is provided with a plurality of winding cores, the arc plate is subjected to a larger force, and the support plate can effectively ensure the supporting effect of the arc plate, thereby avoiding the inclination of the arc plate caused by the expansion of the winding core, and ensuring the stable abutment and limiting of the arc surface.

[0013] As one of the optional embodiments of the present application, the arc plate and the support plate jointly form a liquid collecting cavity, and a communication hole is formed in the arc plate to communicate the accommodating cavity and the liquid collecting cavity.

[0014] In the embodiments of the present application, the design of the communication hole enables the electrolyte entering the liquid collecting cavity during liquid injection to fully enter the accommodating cavity through the communication hole, thereby infiltrating the winding core, so as to ensure the full infiltration of the electrolyte.

[0015] As one of the optional embodiments of the present application, an outer envelope arranged in the accommodating cavity is further provided, the outer envelope has an open accommodating cavity, and the overall structure formed by the winding core, the stabilizing piece and the limiting piece is arranged in the accommodating cavity.

[0016] As one of the optional embodiments of the present application, the stabilizing piece is provided with a plurality of liquid permeation holes penetrating through in the first direction.

[0017] As one of the optional embodiments of the present application, the outer film comprises a bottom film and a side film connected to each other, the bottom film is arranged on the side of the stabilizing piece away from the winding core, and the side film is connected to the circumferential side of the bottom film and extends in the direction of the cover body along the first direction; wherein the bottom film is provided with a plurality of liquid leakage holes penetrating through in the first direction, the orthographic projection of the liquid leakage holes on the bearing surface does not overlap with the orthographic projection of the liquid permeation holes on the bearing surface, and the side of the stabilizing piece away from the winding core is recessed to form a flow channel, in the first direction, the orthographic projection of the liquid permeation holes and the liquid leakage holes on the bearing surface is located in the area defined by the orthographic projection of the flow channel on the bearing surface.

[0018] In the embodiments of the present application, the outer film is used for insulation between the winding core and the shell, the liquid permeation holes are arranged on the stabilizing piece to enable the electrolyte entering the accommodating cavity to be infiltrated from the bottom of the winding core to the winding core through the liquid permeation holes, so as to ensure the smooth infiltration of the electrolyte, in addition, the misalignment design of the liquid leakage holes and the liquid permeation holes further avoids the contact between the winding core and the inner wall of the shell, so as to ensure the insulation performance, and the flow channel is designed to ensure the communication between the liquid leakage holes and the liquid permeation holes, so as to ensure that the electrolyte in the shell can finally enter the winding core through the liquid leakage holes and the liquid permeation holes.

[0019] As one of the optional embodiments of the present application, there is a third direction, the first direction, the second direction and the third direction intersect with each other; along the third direction, the stabilizing piece is arranged on one side of the winding core.

[0020] As one of the optional embodiments of the present application, a plurality of winding cores are arranged, the plurality of winding cores are stacked along the third direction; the stabilizing piece is arranged between two adjacent winding cores, and in the second direction, the two ends of the stabilizing piece are connected with the limiting members arranged at the two ends of the winding core, respectively.

[0021] The present application also discloses a battery pack comprising the monomer battery.

[0022] One of the technical solutions has the following advantages or beneficial effects:

[0023] 1. The stabilizing piece is connected between the two limiting pieces to constrain the relative position of the two limiting pieces in the second direction, which enables the limiting piece to be attached to the arc-shaped surface of the two ends of the roll core through the limiting surface, thereby limiting the arc-shaped surface part of the roll core, so that the positive and negative plates in the roll core can be tightly attached at the corner where the arc-shaped surface is located, ensuring that lithium ions smoothly separate or embed between the positive and negative plates to reduce lithium precipitation. And because the stabilizing piece connects the two limiting pieces, it forms a reliable and stable overall structure with the limiting piece, reducing the relative displacement between the limiting piece and the roll core, which makes the relative position between the limiting piece and the roll core more stable, thereby improving the accuracy of the limiting piece in limiting the arc-shaped surface of the roll core to further reduce lithium precipitation.

[0024] 2. The limiting piece and the stabilizing piece are arranged to make full use of the internal space of the battery shell, ensuring the space utilization of the battery under the premise of reducing lithium precipitation, and making the roll core more stable and reliable inside the shell to improve the performance of the battery. It can be understood that in the related art, the arc-shaped part at both ends of the roll core placed in the shell will have a spacing space between the opposite inner wall of the shell, and a separator will be arranged on the side of the roll core away from the cover. In the present application, the limiting piece is arranged in the spacing space to reduce lithium precipitation of the roll core and ensure the stability of the position of the roll core under the premise of ensuring space utilization. BRIEF DESCRIPTION OF DRAWINGS

[0025] The technical solutions and other beneficial effects of the present application will become apparent from the following detailed description of the specific embodiments of the present application, combined with the accompanying drawings.

[0026] Figure 1 is the overall structure diagram of the single battery provided by the embodiment of the present application;

[0027] Figure 2 is the structure diagram of the single battery along the first direction provided by the embodiment of the present application;

[0028] Figure 3 is the schematic diagram for showing the structure of the limiting piece provided by the embodiment of the present application;

[0029] Figure 4 is the schematic diagram for showing the structure of the limiting piece provided by the embodiment of the present application;

[0030] Figure 5 is the schematic diagram for showing the structure of the limiting piece provided by the embodiment of the present application; Figure 4 is the local enlarged view of part A in the above figure;

[0031] Figure 6 is the schematic diagram for showing the connection structure of the limiting piece and the stabilizing piece provided by the embodiment of the present application;

[0032] Figure 7is a cross-sectional view provided by the embodiment of the present application for showing the positional relationship of the limiting member, the stabilizing member and the outer wrapping film;

[0033] Figure 8 is a cross-sectional view provided by the embodiment of the present application for showing the positional relationship of the limiting member, the stabilizing member and the outer wrapping film; Figure 7 is a local enlarged view of the B part in the middle;

[0034] Figure 9 is a schematic view of the connecting structure of the stabilizing member and the limiting member in another embodiment of the present application;

[0035] Figure 10 is a schematic view of the connecting structure of the stabilizing member and the limiting member in another embodiment of the present application in the installed state;

[0036] Figure 11 is a structural schematic view of the limiting member when the winding core is one.

[0037] Reference signs: 1, shell; 11, shell body; 12, cover body; 10, accommodating cavity;

[0038] 2, winding core; 20, arc surface;

[0039] 3, limiting member; 30, limiting surface; 31, support plate; 32, arc plate; 320, limiting groove; 3a, liquid collecting cavity; 3b, communication hole;

[0040] 4, stabilizing member; 40, bearing surface; 4a, liquid permeation hole; 4b, flow channel;

[0041] 5, outer wrapping film; 51, bottom film; 51a, liquid leakage hole; 52, side film; 50, accommodating cavity;

[0042] Z, first direction; X, second direction; Y, third direction. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0044] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the term "and / or" in this paper is only to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can represent the existence of A alone, the existence of A and B together, and the existence of B alone. In addition, the character " / " in this paper generally represents an "or" relationship between the associated objects without special explanation.

[0045] The following description will be made in conjunction with the accompanying drawings Figures 1-11 Further description is made to the present application.

[0046] Reference is made to Figure 1 and Figure 2 A single battery provided for the application has a first direction Z, a second direction X and a third direction Y intersecting with each other, and the single battery comprises a shell 1 having a receiving cavity 10, and a winding core 2, a limiting piece 3 and a stabilizing piece 4 arranged in the receiving cavity 10.

[0047] Specifically, the shell 1 comprises a shell body 11 having the receiving cavity 10, and a cover body 12 connected to one side of the shell body 11 along the first direction Z and sealing the receiving cavity 10; the winding core 2 is provided with at least one, and the winding core 2 has an arc surface 20 at both ends in the second direction X, which is formed by winding and heat pressing the winding core 2; the limiting piece 3 is provided with a plurality of, and at least one limiting piece 3 is arranged at each end of the winding core 2 in the second direction X.

[0048] In combination Figures 3-5 The limiting piece 3 has a limiting surface 30 facing the arc surface 20, and the limiting surface 30 is in contact with at least part of the arc surface 20; the two ends of the stabilizing piece 4 are respectively connected with the limiting pieces 3 at the two ends of the winding core 2 in the second direction X.

[0049] Specifically, the cover body 12 is provided with a positive pole and a negative pole, and the winding core 2 comprises a positive pole sheet, a negative pole sheet and a diaphragm, which are wound to form a cylindrical or square winding core with a multi-layer structure. In one example, the winding core 2 is approximately square, i.e. the winding core 2 comprises a middle flat part and two arc-shaped parts arranged at both ends of the flat part in the second direction respectively. The winding core 2 is provided with a positive pole lug and a negative pole lug on the side close to the cover body 12, and the positive pole lug and the negative pole lug are respectively welded to the positive pole and the negative pole to realize the electrical conduction of the winding core 2. The cover body 12 is welded to the shell body 11 on the side of the opening to realize the sealing of the receiving cavity 10 by the cover body 12.

[0050] In the embodiment of the present application, the stabilizing piece 4 is connected between the two limiting pieces 3 to constrain the relative position of the two limiting pieces 3 in the second direction X, which enables the limiting piece 3 to abut against the arc-shaped surface 20 at both ends of the roll core 2 through the limiting surface 30, thereby limiting the arc-shaped surface 20 of the roll core 2, so that the positive and negative electrode sheets in the roll core 2 can be closely attached to the arc-shaped surface 20, ensuring that lithium ions smoothly separate or embed between the positive and negative electrode sheets, thereby reducing lithium precipitation. Moreover, since the stabilizing piece 4 connects the two limiting pieces 3, it forms a reliable and stable overall structure with the limiting piece 3, reducing the relative displacement between the limiting piece 3 and the roll core 2, which makes the relative position between the limiting piece 3 and the roll core 2 more stable, thereby improving the accuracy of the limiting piece 3 in limiting the arc-shaped surface 20 of the roll core 2, to further reduce lithium precipitation.

[0051] With reference to Figure 2 As an optional embodiment of the present application, the stabilizing piece 4 is arranged on the side of the roll core 2 away from the cover 12, and the stabilizing piece 4 has a bearing surface 40 facing the roll core 2, and the roll core 2 rests on the bearing surface 40. It can be understood that the roll core 2 resting on the bearing surface 40 means that the side surface of the roll core 2 close to the bearing surface 40 is in contact with the bearing surface 40, and the bearing surface 40 can bear at least part of the pressure of the roll core 2.

[0052] Specifically, the stabilizing piece 4 and the limiting piece 3 are both rigid materials that can stably limit the arc-shaped surface 20. It can be understood that the limiting piece 3 and the stabilizing piece 4 are both rigid materials and are connected to each other, and since they are constrained by the stabilizing piece 4, the relative position between the two limiting pieces 3 is relatively stable, thereby ensuring the abutting effect of the limiting piece 3 on the arc-shaped surface 20. In one example, the stabilizing piece 4 and the limiting piece 3 are made of polyethylene terephthalate (PET) material, which has certain strength and is insulating. The end of the limiting piece 3 close to the stabilizing piece 4 is integrally connected to the stabilizing piece 4, which further ensures the stability of the position of the two. In one example, the stabilizing piece 4 is a plate-shaped structure with a thickness of 0.5 mm. The stabilizing piece 4 and the limiting piece 3 can also be other materials that are insulating, resistant to electrolyte corrosion, and stable in performance in an electrochemical system, and the thickness of the stabilizing piece 4 can be adjusted according to the internal structure of the single battery, and is not limited to 0.5 mm.

[0053] In the embodiment of the present application, the stabilizing piece 4 and the limiting piece 3 jointly form a support structure for bearing and limiting the roll core 2, and the roll core 2 is limited from the bottom surface and both ends of the roll core 2 in the second direction X, so that the limitation of the roll core 2 is more stable and reliable. It can be understood that, because the limiting piece 3 can be better limited by the abutment of the limiting surface 30 and the arc surface 20, if the position between the limiting piece 3 and the roll core 2 is offset, the abutment between the limiting surface 30 and the arc surface 20 will not be tight enough, so that the limiting effect is lost or reduced, and the stability of the position between the limiting piece 3 and the roll core 2 can be effectively ensured by the structural design of the stabilizing piece 4 and the limiting piece 3 in the embodiment of the present application.

[0054] With reference to Figures 3-5 In an optional embodiment, the limiting piece 3 includes an arc-shaped plate 32, the arc-shaped plate 32 is connected to the bearing surface 40, the arc-shaped plate 32 extends along the first direction Z, and the surface of the arc-shaped plate 32 facing the arc surface 20 is the limiting surface 30. The structure of the limiting piece 3 as the arc-shaped plate 32 can abut against the arc surface 20 while reducing the material and space occupation, so as to ensure the energy density of the battery.

[0055] As one of the optional embodiments of the present application, the roll core 2 is provided in plurality, and the plurality of roll cores 2 are stacked along the third direction Y; the limiting piece 3 further includes a support plate 31, the support plate 31 is connected to the side of the arc-shaped plate 32 away from the roll core 2, and the arc-shaped plate 32 is provided one by one corresponding to the roll core 2. Specifically, one by one in the above means that at least one arc-shaped plate 32 should be provided when any one of the roll cores 2 is located at one end of the second direction X, so that at least one arc-shaped plate 32 can abut against and limit the arc surface 20 at one end of the roll core 2. When the roll core 2 is provided in plurality, the arc-shaped plate 32 is subjected to a larger force, and the support plate 31 can effectively ensure the support of the arc-shaped plate 32, avoid the inclination of the arc-shaped plate 32 due to the expansion of the roll core 2, and ensure the stable abutment and limitation of the arc surface 20.

[0056] It should be noted that, in the example of the present application, the roll core 2 is provided in two or more than two, but the case that the roll core 2 is only one is not excluded, for example Figure 11 It is shown in the example that the number of the roll core 2 is one, and the limiting piece 3 includes the arc-shaped plate 32, and the limiting piece 3 can abut against the arc surface 20 completely or partially.

[0057] In the embodiment of the present application, when the roll core 2 is two or more than two, the limiting piece 3 is provided as including the arc-shaped plate 32 and the support plate 31. When the roll core 2 is only one, the limiting piece 3 can only include the arc-shaped plate 32.

[0058] However, it can be understood that when the winding core 2 is only one, the limiting member 3 can also include the support plate 31, and when the winding core 2 is more than two, the limiting member 3 can also only include the arc-shaped plate 32.

[0059] With reference to Figure 3 and Figure 5 , as one of the optional embodiments of the present application, when the winding core 2 is more than two, the arc-shaped plate 32 and the support plate 31 jointly form the liquid collecting cavity 3a, and the arc-shaped plate 32 is provided with the communication hole 3b, which communicates the accommodating cavity 10 and the liquid collecting cavity 3a.

[0060] Specifically, the support plate 31 extends along the first direction Z, and the second direction X is the thickness direction of the support plate 31. The arc-shaped plate 32 is provided with two corresponding winding cores 2, and one side of the arc-shaped plate 32 is integrally connected with the support plate 31 in the first direction Z. The part of the arc-shaped plate 32 away from the support plate 31 is curved in an arc shape. Specifically, the bending trend of the arc-shaped plate 32 should cooperate with the corresponding arc-shaped surface 20, so that the limiting surface 30 on the arc-shaped plate 32 at least partially abuts the arc-shaped surface 20. In some examples, the bending curvatures of the two arc-shaped plates 32 are the same, and the distance between the two arc-shaped plates 32 gradually decreases along the direction from the arc-shaped part of the winding core 2 to the flat part of the winding core 2. This makes the arc-shaped plate 32 and the support plate 31 jointly form the liquid collecting cavity 3a. In the embodiment of the present application, a space is left between the sides of the two arc-shaped plates 32 close to each other, and this part of the space forms the communication hole 3b for communicating the liquid collecting cavity 3a and the accommodating cavity 10.

[0061] In the embodiment of the present application, the design of the communication hole 3b enables the electrolyte entering the liquid collecting cavity 3a to fully enter the accommodating cavity 10 through the communication hole 3b during liquid injection, so as to be soaked on the winding core 2, thereby ensuring sufficient soaking of the electrolyte.

[0062] It should be noted that the structure of the communication hole 3b is not limited to the embodiment of the present application. For example, in one optional example, the sides of the two arc-shaped plates 32 away from the support plate 31 are partially closed, which makes the communication hole 3b not a continuous hole along the first direction Z, but a hole formed at intervals in the first direction Z; or in another optional example, the sides of the two arc-shaped plates 32 away from the support plate 31 are completely connected and closed to each other, and the communication hole 3b is recessed from the limiting surface 30 and penetrates the arc-shaped plate 32, which can also achieve the communication between the accommodating cavity 10 and the liquid collecting cavity 3a. In some examples, the central axis of the communication hole 3b is parallel or coaxial with the normal direction of the corresponding part of the arc-shaped surface 20.

[0063] With reference to Figure 2 , Figures 6-8As one of the optional embodiments of the present application, the outer envelope 5 is arranged in the accommodating cavity 10, and the outer envelope 5 has an open accommodating cavity 50, and the overall structure formed by the roll core 2, the stabilizing piece 4 and the limiting piece 3 is arranged in the accommodating cavity 50.

[0064] As one of the optional embodiments of the present application, the stabilizing piece 4 is provided with a plurality of liquid permeation holes 4a penetrating in the first direction Z. The outer envelope 5 includes a bottom film 51 and a side film 52 connected to each other, the bottom film 51 is arranged on the side of the stabilizing piece 4 away from the roll core 2, and the side film 52 is connected to the circumferential side of the bottom film 51 and extends in the first direction Z; specifically, the side film 52 is provided with four pieces and is connected to the circumferential side of the bottom film 51, in the first direction Z, one end of the side film 52 away from the cover body 12 is connected to the bottom film 51, and the other end of the side film 52 extends in the direction of the cover body 12; wherein the bottom film 51 is provided with a plurality of liquid leakage holes 51a penetrating in the first direction Z, the orthographic projection of the liquid leakage holes 51a on the bearing surface 40 does not overlap with the orthographic projection of the liquid permeation holes 4a on the bearing surface 40, and the side of the stabilizing piece 4 away from the roll core 2 is recessed to form a flow-through groove 4b, and the liquid permeation holes 4a and the liquid leakage holes 51a are arranged in the coverage range of the flow-through groove 4b.

[0065] It can be understood that the liquid permeation holes 4a and the liquid leakage holes 51a arranged in the coverage range of the flow-through groove 4b means that, in the first direction, the orthographic projection of the liquid permeation holes 4a and the liquid leakage holes 51a on the bearing surface 40 are all located in the area defined by the orthographic projection of the flow-through groove 4b on the bearing surface 40.

[0066] Specifically, the outer envelope 5 can be made of polypropylene (PP) material, which is corrosion-resistant; the bottom of the outer envelope 5 is punched to form the liquid leakage holes 51a, and the diameter of the liquid leakage holes 51a is 1-3 mm, and in one example, the diameter of the liquid leakage holes 51a is 2 mm. Of course, the diameter of the liquid leakage holes 51a can also be selected in other ranges other than 1-3 mm, which is determined comprehensively according to the capacity size of the battery, the type of the battery, etc.

[0067] In the embodiments of the present application, the outer envelope 5 is used for insulation between the roll core 2 and the shell 11, the liquid permeation holes 4a are arranged on the stabilizing piece 4 to enable the electrolyte entering the accommodating cavity 50 to infiltrate into the roll core 2 from the bottom of the roll core 2, thereby ensuring smooth infiltration of the electrolyte, in addition, the staggered design of the liquid leakage holes 51a and the liquid permeation holes 4a further avoids the contact between the roll core 2 and the inner wall of the shell 11, thereby ensuring the insulation performance, and the design of the flow-through groove 4b is to ensure the smooth communication between the liquid leakage holes 51a and the liquid permeation holes 4a, thereby ensuring that the electrolyte in the shell 11 can finally enter the roll core 2 through the liquid leakage holes 51a and the liquid permeation holes 4a.

[0068] It should be noted that the orthographic projection of leakage hole 51a on bearing surface 40 and leakage hole 4a on bearing surface 40 do not overlap, meaning that leakage hole 51a and leakage hole 4a neither coincide nor intersect each other. In one example, for instance... Figure 8 As shown, the leakage hole 51a and the seepage hole 4a have the same diameter and are spaced apart from each other in the second direction X. This arrangement is for insulation considerations. It is understandable that if there is an intersection between the leakage hole 51a and the seepage hole 4a, as the number of charge and discharge cycles increases, when some active material on the core 2 falls off, it will be easier for it to come into direct contact with the outer casing 1 through the leakage hole 51a and the seepage hole 4a, which may lead to a short circuit in the core 2.

[0069] It should be noted that in some optional examples, there may be partial overlap between the leakage hole 51a and the seepage hole 4a. The area of ​​the overlapping region is small enough to prevent the active material from contacting the inner wall of the shell 11 through the overlapping area from the core 2. The area of ​​the overlapping region is set according to the particle size of the active material. In some examples, the area of ​​the overlapping region between the leakage hole 51a and the seepage hole 4a is less than or equal to 0.4 mm. 2 .

[0070] Reference Figure 9 and Figure 10 As one optional embodiment of this application, along the third direction Y, the stabilizing member 4 is disposed on one side of the core 2. In one example, multiple cores 2 are disposed, and the multiple cores 2 are stacked along the third direction Y; the stabilizing member 4 is sandwiched between two adjacent cores 2, and in the second direction X, the two ends of the stabilizing member 4 are respectively connected to the limiting members 3 at both ends of the core 2.

[0071] In this embodiment, the stabilizing member 4 can also be disposed on the side of the core 2 along the third direction Y, that is, the stabilizing member 4 is disposed on the larger surface side of the core 2. The larger surface side refers to the two opposite sides of the core 2 with the largest area, which in this embodiment refers to the two sides of the core 2 facing each other in the third direction Y. It should be noted that when there are multiple cores 2, in this example the stabilizing member 4 is disposed between two cores 2, but in other alternative embodiments, the stabilizing member 4 can also be disposed on the side of the two cores 2 that are opposite to each other.

[0072] This application also discloses a battery pack, including the aforementioned single battery cell.

[0073] The above merely describes some embodiments of the present application, and does not limit the present application in any form. The protection scope of the present application is not limited to this, and any person skilled in the art can easily think of simple modifications, equivalent changes and modifications within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A single-cell battery, characterized in that, Having intersecting first direction (Z) and second direction (X), the single cell comprises: The outer casing (1) includes a housing (11) and a cover (12), the housing (11) having a receiving cavity (10), and the cover (12) being connected to one side of the housing (11) along the first direction (Z) and covering the receiving cavity (10); At least one core (2) is disposed in the receiving cavity (10), and the core (2) has an arc-shaped surface (20) at both ends in the second direction (X); A limiting member (3) is disposed in the receiving cavity (10). Multiple limiting members (3) are provided. In the second direction (X), at least one limiting member (3) is provided at each end of the core (2). The limiting member (3) has a limiting surface (30) facing the arc surface (20), and the limiting surface (30) is in close contact with at least a portion of the arc surface (20). A stabilizing member (4) is disposed in the receiving cavity (10). In the second direction (X), the two ends of the stabilizing member (4) are respectively connected to the limiting members (3) located at both ends of the core (2).

2. The single-cell battery as described in claim 1, characterized in that, The stabilizing member (4) is disposed on the side of the core (2) away from the cover (12), and the stabilizing member (4) has a bearing surface (40) facing the core (2), on which the core (2) rests.

3. The single-cell battery as described in claim 2, characterized in that, The limiting member (3) includes an arc-shaped plate (32), which is connected to the bearing surface (40). The arc-shaped plate (32) extends along the first direction (Z), and the surface of the arc-shaped plate (32) facing the arc-shaped surface (20) is the limiting surface (30).

4. The single-cell battery as described in claim 3, characterized in that, It also has a third direction (Y), the first direction (Z), the second direction (X) and the third direction (Y) intersect each other, and multiple cores (2) are provided, and multiple cores (2) are stacked along the third direction (Y); The limiting member (3) also includes a support plate (31), which is connected to the side of the arc plate (32) away from the core (2), and the arc plate (32) is provided one-to-one with the core (2).

5. The single-cell battery as described in claim 4, characterized in that, The arc-shaped plate (32) and the support plate (31) together form a liquid collection cavity (3a). A connecting hole (3b) is provided on the arc-shaped plate (32), and the connecting hole (3b) connects the accommodating cavity (10) and the liquid collection cavity (3a).

6. The single-cell battery as described in claim 2, characterized in that, It also includes an outer film (5) disposed in the receiving cavity (10), the outer film (5) having an open receiving cavity (50), and the integral structure formed by the core (2), the stabilizing member (4) and the limiting member (3) is disposed in the receiving cavity (50).

7. The single-cell battery as described in claim 6, characterized in that, The stabilizing member (4) has multiple seepage holes (4a) that extend along the first direction (Z).

8. The single-cell battery as described in claim 7, characterized in that, The outer film (5) includes a bottom film (51) and a side film (52) connected to each other. The bottom film (51) is disposed on the side of the stabilizing member (4) away from the core (2). The side film (52) is connected to the periphery of the bottom film (51) and extends along the first direction (Z) toward the direction where the cover (12) is located. The bottom film (51) has a plurality of leakage holes (51a) extending along the first direction (Z). The orthographic projection of the leakage hole (51a) on the bearing surface (40) and the orthographic projection of the seepage hole (4a) on the bearing surface (40) do not overlap. The side of the stabilizing member (4) facing away from the core (2) has a recessed flow groove (4b). In the first direction (Z), the orthographic projections of the seepage hole (4a) and the leakage hole (51a) on the bearing surface (40) are both located within the area defined by the orthographic projection of the flow groove (4b) on the bearing surface (40).

9. The single-cell battery as described in claim 1, characterized in that, It also has a third direction (Y), and the first direction (Z), the second direction (X), and the third direction (Y) intersect each other; Along the third direction (Y), the stabilizing member (4) is disposed on one side of the core (2).

10. The single-cell battery as described in claim 9, characterized in that, Multiple cores (2) are provided, and the multiple cores (2) are stacked along the third direction (Y); the stabilizing member (4) is sandwiched between two adjacent cores (2), and in the second direction (X), the two ends of the stabilizing member (4) are respectively connected to the limiting member (3) located at both ends of the core (2).

11. A battery pack, characterized in that, Including the single cell battery as described in any one of claims 1-10.

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