Single battery and battery pack

Abstract

The invention provides a single battery and a battery pack, and relates to the technical field of secondary batteries. Each single battery comprises a shell, a first cover plate, a roll core and a first current collector; the first cover plate is connected with one end of the shell; the roll core is arranged in the shell, at least one liquid storage cavity is formed between the roll core and the adjacently connected side wall, and a through liquid injection channel is formed in the roll core; the first flow collecting piece is connected with the roll core and the first cover plate, the first flow collecting piece is provided with a through liquid inlet hole, and the liquid inlet hole communicates with the liquid injection channel; a groove is formed in the side, close to the first cover plate, of the first flow collecting piece, the groove is sunken in the direction away from the first cover plate, and the groove communicates with the liquid storage cavity and the liquid inlet hole. The electrolyte stored in the liquid storage cavity can continuously flow into the liquid inlet hole through the groove and then is supplemented into the liquid injection channel to keep the roll core infiltrated, so that the roll core can be fully infiltrated with the electrolyte, the cycle performance and the safety performance of the single battery are further improved, and the service life of the single battery is prolonged.

Description

Technical Field

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

[0002] As representatives of new energy vehicles, hybrid electric vehicles and pure electric vehicles have gradually been recognized by the majority of manufacturers and consumers. As the main power source of new energy vehicles, power batteries have become one of the key components of electric vehicles.

[0003] Existing batteries have the problem of insufficient infiltration of the electrolyte into the wound core, resulting in the formation of "dead zones", which limits the transmission of lithium ions, and further limits the cycle performance, safety performance and service life of the batteries. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, one of the purposes of the present invention is to provide a single cell.

[0005] The present invention provides the following technical solutions:

[0006] A single cell having a first direction, the single cell comprising:

[0007] A housing including a plurality of side walls;

[0008] A first cover plate connected to one end of the housing along the first direction;

[0009] A wound core disposed in the housing, at least one liquid storage cavity being formed between the wound core and the adjacent connected side walls, the wound core being provided with a liquid injection channel penetrating along the first direction, the liquid injection channel communicating with the liquid storage cavity;

[0010] And

[0011] A first current collector disposed in the housing and connected to the wound core and the first cover plate respectively along the first direction, the first current collector being provided with a liquid inlet hole penetrating along the first direction, the liquid inlet hole communicating with the liquid injection channel; a groove is provided on a side of the first current collector close to the first cover plate, the groove being recessed in a direction away from the first cover plate along the first direction, the groove communicating with the liquid storage cavity and the liquid inlet hole.

[0012] As a further optional solution to the single cell, a part of the first current collector protrudes along the first direction to form a protruding portion, the protruding portion forming the groove on a side of the first current collector facing the first cover plate; the protruding portion is provided with a first liquid immersion hole penetrating along the first direction, the first liquid immersion hole communicating with the groove.

[0013] As a further optional solution for the single cell, the liquid inlet hole corresponds to the liquid injection channel, there are multiple protrusions, and the multiple protrusions are arranged around the liquid inlet hole and extend in a direction away from the liquid inlet hole respectively.

[0014] As a further optional solution for the single battery, each of the protruding portions is provided with a plurality of the first liquid immersion holes, and the plurality of the first liquid immersion holes are arranged at intervals along an extension direction of the corresponding protruding portion.

[0015] As a further optional solution for the single cell battery, the shell also includes a second cover plate connected to multiple side walls, the multiple side walls are arranged around the winding core, the second cover plate is connected to one end of the side wall away from the first cover plate along the first direction, and the first cover plate, the second cover plate and the multiple side walls are connected, and the liquid storage chamber is formed between adjacent side walls and the winding core.

[0016] As a further optional solution for the single battery, the number of the liquid storage chambers is multiple, the multiple liquid storage chambers include multiple interconnected liquid storage spaces, the multiple side walls include a first side wall, a second side wall and a third side wall, the first side wall is connected to the second side wall, and the third side wall is connected to the first side wall and the second side wall respectively;

[0017] The winding core is tangent to the first side wall, the second side wall and the third side wall respectively, and the liquid storage space is formed between the winding core and the first side wall and the second side wall respectively, the liquid storage space is formed between the first side wall and the third side wall, and the liquid storage space is formed between the second side wall and the third side wall.

[0018] As a further optional solution for the single battery, the maximum distance between the axis of the winding core and the side wall is not less than the diameter of the winding core.

[0019] As a further optional solution for the single cell, the single cell further includes an electrode terminal and a second current collector;

[0020] The electrode terminal is disposed through the second cover plate;

[0021] The second current collecting member is arranged in the shell, the second current collecting member is connected to one end of the winding core away from the first current collecting member along the first direction, the second current collecting member is fixedly connected to the electrode terminal, and the second current collecting member is provided with a second immersion hole penetrating along the first direction, and the second immersion hole is connected to the liquid storage chamber.

[0022] As a further optional solution for the single cell, the single cell further includes a first insulating member disposed on a side of the second cover plate facing the wound core along the first direction;

[0023] The second current collector includes a connecting portion and an immersion portion surrounding the connecting portion. The connecting portion is connected to the electrode terminal. The second immersion hole is disposed on the immersion portion. A gap is formed between the immersion portion and the first insulating member. The second immersion hole communicates with the liquid storage cavity through the gap.

[0024] As a further optional solution for the single cell, the first cover plate is provided with a liquid injection hole penetrating along the first direction. The liquid injection hole is disposed opposite to the liquid injection channel along the first direction. The liquid injection hole communicates with the groove and the liquid injection channel.

[0025] Another object of the present invention is to provide a battery pack.

[0026] The present invention provides the following technical solutions:

[0027] A battery pack includes the above single cell.

[0028] The embodiments of the present invention have the following beneficial effects:

[0029] In the above single cell, the liquid storage cavity can increase the space for accommodating the electrolyte, ensuring that the wound core can be fully wetted by the electrolyte. At the same time, the first current collector is provided with a penetrating liquid inlet hole, and the liquid inlet hole communicates with the liquid injection channel that penetrates the wound core along the first direction; a groove is provided on a side of the first current collector close to the first cover plate, and the groove is recessed along the first direction away from the first cover plate, and communicates with the liquid storage cavity and the liquid inlet hole respectively. When assembling the above single cell, the electrolyte is injected into the liquid inlet hole. A part of the electrolyte flows into the liquid injection channel through the liquid inlet hole and directly wets the wound core; another part of the electrolyte flows into the groove through the liquid inlet hole, and then flows into the liquid storage cavity through the groove and is stored in the liquid storage cavity. During the long-term use of the single cell, the electrolyte in the liquid injection channel that is in direct contact with the wound core gradually wears out. At this time, the electrolyte stored in the liquid storage cavity can continuously flow into the liquid inlet hole through the groove, and then be replenished into the liquid injection channel to maintain the wetting of the wound core, so that the wound core can be fully wetted by the electrolyte, reduce or eliminate the "dead zone", and thus improve the cycle performance and safety performance of the single cell and extend the service life of the single cell.

[0030] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following specific preferred embodiments are given below in conjunction with the accompanying drawings and are described in detail as follows. Description of the Drawings

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0032] Figure 1 It shows a schematic diagram of the overall structure of a single battery provided by an embodiment of the present invention;

[0033] Figure 2 It shows an exploded view of a single battery provided by an embodiment of the present invention;

[0034] Figure 3 It shows a longitudinal sectional view of a single battery provided by an embodiment of the present invention;

[0035] Figure 4 It shows a schematic diagram of the structure of the first current collector in a single battery provided by an embodiment of the present invention;

[0036] Figure 5 It shows a sectional view of the first cover plate and the first current collector in a single battery provided by an embodiment of the present invention;

[0037] Figure 6 It shows a transverse sectional view of a single battery provided by an embodiment of the present invention;

[0038] Figure 7 It shows a schematic diagram of the structure of the terminal assembly, the second cover plate and the second current collector in a single battery provided by an embodiment of the present invention;

[0039] Figure 8 It shows a sectional view of the terminal assembly, the second cover plate and the second current collector in a single battery provided by an embodiment of the present invention;

[0040] Figure 9 It shows a schematic diagram of the arrangement and distribution of multiple single batteries.

[0041] Main element symbol description:

[0042] 10 - single battery;

[0043] 100 - housing; 101 - liquid storage chamber; 101a - liquid storage space; 110 - side wall; 111 - first side wall; 112 - second side wall; 113 - third side wall; 120 - second cover plate; 200 - first cover plate; 210 - liquid injection hole; 300 - winding core; 310 - liquid injection channel; 400 - first current collector; 410 - liquid inlet hole; 420 - protrusion; 421 - first liquid immersion hole; 430 - groove; 500 - terminal assembly; 510 - electrode terminal; 511 - first column part; 512 - second column part; 513 - third column part; 520 - first insulating part; 530 - second insulating part; 540 - sealing ring; 600 - second current collector; 610 - second liquid immersion hole; 620 - connecting part; 630 - liquid immersion part; 640 - gap; Z - first direction; X - second direction. Detailed Embodiment

[0044] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

[0045] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time. On the contrary, when an element is referred to as being "directly on" another element, there is no middle element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0046] In the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. It can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise clearly and specifically defined.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of the template herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0049] Embodiment

[0050] Please refer to Figure 1 and Figure 2 simultaneously. In this embodiment, a single cell 10 is provided. The single cell 10 has a first direction Z, and the single cell 10 includes a housing 100, a first cover plate 200, a wound core 300, and a first current collector 400.

[0051] Among them, the housing 100 includes a plurality of side walls 110, and the first cover plate 200 is connected to one end of the housing 100 along the first direction Z.

[0052] Please refer to Figure 3 simultaneously. The wound core 300 is disposed inside the housing 100. At least one liquid storage cavity 101 is formed between the wound core 300 and the adjacent connected side walls 110, and the liquid storage cavity 101 is formed between the inner walls of the housing 100. A liquid injection channel 310 penetrating along the first direction Z is provided inside the wound core 300, and the liquid injection channel 310 is communicated with the liquid storage cavity 101.

[0053] Please refer to Figure 4 and Figure 5 simultaneously. The first current collector 400 is disposed inside the housing 100, and the first current collector 400 is respectively connected to the wound core 300 and the first cover plate 200 along the first direction Z. The first current collector 400 is provided with a liquid inlet hole 410 penetrating along the first direction Z, and the liquid inlet hole 410 is communicated with the liquid injection channel 310.

[0054] In addition, a groove 430 is provided on one side of the first current collector 400 close to the first cover plate 200. The groove 430 is recessed in a direction away from the first cover plate 200 along the first direction Z, and the groove 430 is communicated with the liquid storage cavity 101 and the liquid inlet hole 410.

[0055] It can be understood that the communication between the liquid injection channel 310 and the liquid storage cavity 101 specifically means that the liquid injection channel 310 is communicated with the liquid storage cavity 101 through the liquid inlet hole 410 and the groove 430 in sequence.

[0056] In the above-mentioned single cell 10, a liquid storage cavity 101 is formed between the winding core 300 and the inner wall of the housing 100, and the liquid storage cavity 101 can increase the space for accommodating the electrolyte. At the same time, the first current collector 400 is provided with a through liquid inlet hole 410, and the liquid inlet hole 410 is communicated with a liquid injection channel 310 that penetrates the winding core 300 along the first direction Z; a groove 430 is provided on one side of the first current collector 400 close to the first cover plate 200, and the groove 430 is recessed along the first direction Z away from the first cover plate 200 and is communicated with the liquid storage cavity 101 and the liquid inlet hole 410 respectively.

[0057] When assembling the above-mentioned single cell 10, the electrolyte is injected into the liquid inlet hole 410. A part of the electrolyte flows into the liquid injection channel 310 through the liquid inlet hole 410 and directly infiltrates the winding core 300; another part of the electrolyte flows into the groove 430 through the liquid inlet hole 410, and then flows into the liquid storage cavity 101 through the groove 430 and is stored in the liquid storage cavity 101.

[0058] During the long-term use of the single cell 10, the electrolyte in direct contact with the winding core 300 in the liquid injection channel 310 gradually loses. At this time, the electrolyte stored in the liquid storage cavity 101 can continuously flow into the liquid inlet hole 410 through the groove 430, and then be replenished into the liquid injection channel 310 to maintain the infiltration of the winding core 300, so that the winding core 300 can be fully infiltrated with the electrolyte, reduce or eliminate the "dead zone", and further improve the cycle performance and safety performance of the single cell 10 and extend the service life of the single cell 10.

[0059] Please refer to Figure 5 In some embodiments, the first cover plate 200 is provided with a liquid injection hole 210 that penetrates along the first direction Z. The liquid injection hole 210 is arranged opposite to the liquid injection channel 310 along the first direction Z, and the liquid injection hole 210 is communicated with the groove 430 and the liquid injection channel 310.

[0060] Specifically, the first cover plate 200, the first current collector 400 and the winding core 300 are arranged in sequence along the first direction Z, and the liquid injection hole 210 penetrating the first cover plate 200, the liquid inlet hole 410 penetrating the first current collector 400 and the liquid injection channel 310 penetrating the winding core 300 are communicated in sequence along the first direction Z. At the same time, the liquid injection hole 210 is also communicated with the liquid storage cavity 101 through the liquid inlet hole 410 and the groove 430.

[0061] When assembling the above battery cells, electrolyte is injected into the interior of the housing 100 through the liquid injection hole 210. The electrolyte directly flows into the liquid inlet hole 410. A part of the electrolyte flows into the liquid injection channel 310 to soak the wound core 300; another part of the electrolyte flows into the liquid storage cavity 101 through the groove 430 and is stored in the liquid storage cavity 101. During long-term use, the electrolyte stored in the liquid storage cavity 101 continuously flows into the liquid inlet hole 410 through the groove 430, and then into the liquid injection channel 310, so that the wound core 300 can be fully soaked with the electrolyte.

[0062] Please refer to Figure 4 and Figure 5 In some embodiments, a part of the first current collector 400 protrudes along the first direction Z to form a protruding part 420, and the protruding part 420 forms the aforementioned groove 430 on the side of the first current collector 400 facing the first cover plate 200. In addition, the protruding part 420 is provided with a first liquid immersion hole 421 penetrating along the first direction Z, and the first liquid immersion hole 421 communicates with the groove 430.

[0063] Specifically, the first liquid immersion hole 421 is directly communicated with the groove 430, and then communicates with the liquid storage cavity 101 through the groove 430.

[0064] In addition, the protruding part 420 protrudes in a direction away from the first cover plate 200 along the first direction Z and abuts against one end face of the wound core 300 along the first direction Z. On this basis, the first liquid immersion hole 421 penetrates the protruding part 420 along the first direction Z, so that a part of the end face of the wound core 300 is exposed.

[0065] Thus, the electrolyte stored in the liquid storage cavity 101 can also flow into the first liquid immersion hole 421 through the groove 430, and then soak the wound core 300 from the end face of the wound core 300, and the soaking effect is better, which is beneficial to the wound core 300 being more fully soaked with the electrolyte.

[0066] In some embodiments, the liquid inlet hole 410 corresponds to the liquid injection channel 310, and there are multiple protruding parts 420. The multiple protruding parts 420 are arranged around the liquid inlet hole 410 and extend respectively in a direction away from the liquid inlet hole 410.

[0067] It can be understood that the liquid storage cavity 101 is formed between the wound core 300 and the inner wall of the housing 100 and is located on the periphery of the wound core 300. At the same time, the first current collector 400 is arranged opposite to the wound core 300 along the first direction Z, and the projections of the first current collector 400 and the wound core 300 on the first cover plate 200 coincide along the first direction Z. Therefore, the liquid storage cavity 101 is also located on the periphery of the first current collector 400.

[0068] On this basis, the liquid inlet hole 410 is arranged in the central area of the first current collector 400, and the convex part 420 extends along the direction away from the liquid inlet hole 410 to the edge area of the first current collector 400. Thus, one end of the groove 430 formed below the convex part 420 communicates with the liquid inlet hole 410, and the other end communicates with the liquid storage cavity 101.

[0069] On the one hand, since a plurality of convex parts 420 are arranged around the liquid inlet hole 410, the electrolyte stored in each part of the liquid storage cavity 101 located outside the first current collector 400 can flow into the liquid injection channel 310 and the first liquid immersion hole 421 through the groove 430, so as to infiltrate the winding core 300.

[0070] On the other hand, a plurality of convex parts 420 are arranged around the liquid inlet hole 410, which can also uniformly support the winding core 300, facilitating the winding core 300 to remain stable in the housing 100.

[0071] Exemplarily, the number of the convex parts 420 is four, and the four convex parts 420 are uniformly arranged around the liquid inlet hole 410. Every two convex parts 420 are located on the same straight line and extend in opposite directions.

[0072] Furthermore, a plurality of first liquid immersion holes 421 are provided on each convex part 420, and the plurality of first liquid immersion holes 421 are arranged at intervals along the extending direction of the corresponding convex part 420.

[0073] As described above, one end face of the winding core 300 along the first direction Z is partially exposed through the first liquid immersion hole 421, and the electrolyte stored in the liquid storage cavity 101 can flow into the first liquid immersion hole 421 through the groove 430, and then infiltrate the winding core 300 from the end face of the winding core 300.

[0074] Providing a plurality of first liquid immersion holes 421 on each convex part 420 can increase the area of the end face of the winding core 300 infiltrated by the electrolyte and enhance the infiltration effect. Arranging the plurality of first liquid immersion holes 421 at intervals along the extending direction of the corresponding convex part 420 can enable the end face of the winding core 300 to be uniformly infiltrated, and the infiltration effect is better.

[0075] Exemplarily, three first liquid immersion holes 421 are provided on each convex part 420, and the three first liquid immersion holes 421 are uniformly arranged along the extending direction of the corresponding convex part 420.

[0076] Please refer to Figure 3 and Figure 6In some embodiments, the housing 100 further includes a second cover plate 120 connected to the plurality of side walls 110, and the plurality of side walls 110 are disposed around the winding core 300. The second cover plate 120 is connected to one end of the side wall 110 away from the first cover plate 200 along the first direction Z. The first cover plate 200 and the second cover plate 120 are respectively connected to both ends of the side wall 110 along the first direction Z, and the first cover plate 200, the second cover plate 120 and the plurality of side walls 110 are connected, and a liquid storage chamber 101 is formed between adjacent side walls 110 and the winding core 300.

[0077] Specifically, each side wall 110 is respectively extended along the first direction Z, the first cover plate 200 is simultaneously connected to one end of each side wall 110 along the first direction Z, and the second cover plate 120 is simultaneously connected to the other end of each side wall 110 along the first direction Z, thereby enclosing and forming a closed chamber. The winding core 300 is disposed in the chamber, and the cavity around the winding core 300 is the liquid storage chamber 101.

[0078] In some embodiments, there are multiple liquid storage chambers 101, and the multiple liquid storage chambers 101 include multiple interconnected liquid storage spaces 101a.

[0079] The plurality of side walls 110 include a first side wall 111, a second side wall 112, and a third side wall 113. The first side wall 111 is connected to the second side wall 112, and the third side wall 113 is connected to the first side wall 111 and the second side wall 112, respectively.

[0080] In addition, the winding core 300 is tangent to the first side wall 111, the second side wall 112 and the third side wall 113 respectively, and a liquid storage space 101a is formed between the winding core 300 and the first side wall 111 and the second side wall 112, a liquid storage space 101a is formed between the first side wall 111 and the third side wall 113, and a liquid storage space 101a is formed between the second side wall 112 and the third side wall 113.

[0081] It can be understood that the first side wall 111, the second side wall 112 and the third side wall 113 are connected end to end along the peripheral direction of the housing 100, and together constitute a complete side surface of the housing 100. At this time, the cross section of the housing 100 is set in a triangular shape. Correspondingly, the first cover plate 200 and the second cover plate 120 are both triangular plates, which are adapted to the shape enclosed by the first side wall 111, the second side wall 112 and the third side wall 113.

[0082] Meanwhile, the winding core 300 is tangent to the first side wall 111, the second side wall 112, and the third side wall 113 respectively, dividing the closed chamber formed by enclosing the first cover plate 200, the second cover plate 120, and each side wall 110 into three independent liquid storage spaces 101a. In other words, a liquid storage space 101a is formed between the winding core 300, the first side wall 111, and the second side wall 112, another liquid storage space 101a is formed between the winding core 300, the second side wall 112, and the third side wall 113, and yet another liquid storage space 101a is formed between the winding core 300, the first side wall 111, and the third side wall 113.

[0083] Exemplarily, the widths of the first side wall 111, the second side wall 112, and the third side wall 113 are equal, and the cross-section of the housing 100 is an equilateral triangle. In addition, the winding core 300 is cylindrically arranged, and the center of the winding core 300 coincides with the center of the housing 100.

[0084] Alternatively, any two of the first side wall 111, the second side wall 112, and the third side wall 113 have equal widths.

[0085] Or, the widths of the first side wall 111, the second side wall 112, and the third side wall 113 are all unequal.

[0086] Optionally, the materials of the first cover plate 200, the second cover plate 120, and the plurality of side walls 110 are aluminum or steel.

[0087] Furthermore, rounded corners are provided at the joints of the first side wall 111 and the second side wall 112, the joint of the second side wall 112 and the third side wall 113, and the joint of the first side wall 111 and the third side wall 113 for smooth transition. Among them, the radius of the rounded corner inside the housing 100 is smaller than the radius of the rounded corner outside the housing 100.

[0088] Furthermore, the maximum distance between the axis of the winding core 300 and the side wall 110 is not less than the diameter of the winding core 300.

[0089] It can be understood that the middle part of the side wall 110 along its own width direction is tangent to the winding core 300, and the distance from the axis of the winding core 300 is the smallest and equal to the radius of the winding core 300. Accordingly, the distance from the edge of the side wall 110 along its own width direction to the axis of the winding core 300 is the largest.

[0090] That is to say, the maximum distance between the axis of the winding core 300 and the side wall 110 specifically refers to the distance between the axis of the winding core 300 and the joint of the adjacent side wall 110. When this distance is not less than the diameter of the winding core 300, the volume of the liquid storage space 101a formed between the winding core 300 and the side wall 110 is larger, which can hold enough electrolyte, and thus can soak the winding core 300 for a long time, making the soaking effect better.

[0091] Specifically, taking the second side wall 112 and the third side wall 113 as an example, the above-mentioned single battery 10 also has a second direction X, and the second direction X is perpendicular to the first side wall 111 .

[0092] At the same time, the maximum distance between the axis of the core 300 and the second side wall 112 is the distance between the axis of the core 300 and the second side wall 112 along the second direction X, and the maximum distance between the axis of the core 300 and the third side wall 113 is the distance between the axis of the core 300 and the third side wall 113 along the second direction X. The distance is made not less than the diameter of the core 300, so that the volume of the liquid storage space 101a formed between the core 300, the second side wall 112 and the third side wall 113 is larger and can accommodate sufficient electrolyte.

[0093] Please also read Figure 7 and Figure 8 In some embodiments, the single battery 10 further includes an electrode terminal 510 and a second current collector 600 .

[0094] The electrode terminal 510 is disposed through the second cover plate 120 .

[0095] The second current collector 600 is disposed in the housing 100, and is connected to one end of the winding core 300 away from the first current collector 400 along the first direction Z, and is fixedly connected to the electrode terminal 510. The second current collector 600 is provided with a second immersion hole 610 penetrating along the first direction Z, and the second immersion hole 610 is communicated with the liquid storage chamber 101.

[0096] Similar to the first immersion hole 421, one end of the winding core 300 away from the first current collector 400 along the first direction Z is connected to the second current collector 600, and the end surface is partially exposed to the outside through the second immersion hole 610 that penetrates the second current collector 600. Since the second immersion hole 610 is connected to the liquid storage chamber 101, the electrolyte stored in the liquid storage chamber 101 can also flow into the second immersion hole 610, and then infiltrate the winding core 300 from the other end of the winding core 300, the infiltration effect is better, and it is also conducive to more fully infiltrating the electrolyte in the winding core 300.

[0097] In some embodiments, the single battery 10 further includes a first insulating member 520 , and the first insulating member 520 is disposed on a side of the second cover plate 120 along the first direction Z facing the winding core 300 .

[0098] Accordingly, the second current collecting member 600 includes a connecting portion 620 and an immersion portion 630 surrounding the connecting portion 620. The connecting portion 620 is connected to the electrode terminal 510. The second immersion hole 610 is provided on the immersion portion 630, and a gap 640 is formed between the immersion portion 630 and the first insulating member 520. The second immersion hole 610 is connected to the liquid storage chamber 101 through the gap 640.

[0099] It can be understood that the electrode terminal 510 is simultaneously provided in the second cover plate 120 and the first insulating member 520, and one end of the electrode terminal 510 facing the second current collector 600 along the first direction Z protrudes from the side of the first insulating member 520 away from the second cover plate 120 along the first direction Z. When the connecting portion 620 at the center of the second current collector 600 is connected to the electrode terminal 510, a gap 640 is formed between the immersion portion 630 at the periphery of the second current collector 600 and the first insulating member 520. Accordingly, the electrolyte stored in the liquid storage chamber 101 flows into the second immersion hole 610 through the gap 640.

[0100] Specifically, the electrode terminal 510 is composed of a first column portion 511, a second column portion 512 and a third column portion 513. The first column portion 511, the second column portion 512 and the third column portion 513 are sequentially connected along the first direction Z, and the diameter of the second column portion 512 is smaller than that of the first column portion 511 and the third column portion 513.

[0101] The first column portion 511 is located on a side of the second cover plate 120 away from the first insulating member 520 along the first direction Z. The above-mentioned single battery 10 further includes a second insulating member 530, which is disposed around the first column portion 511, and the first column portion 511 is abutted against the second cover plate 120 through the second insulating member 530, and the first column portion 511 and the second cover plate 120 are kept in an insulated state through the second insulating member 530.

[0102] The second column 512 is disposed through the second cover plate 120 and the first insulating member 520. The single battery 10 further includes a sealing ring 540 disposed around the second column 512. The second column 512 and the second cover plate 120 are insulated by the sealing ring 540.

[0103] The third column portion 513 is located on one side of the second cover plate 120 along the first direction Z toward the winding core 300. The third column portion 513 is abutted against the second cover plate 120 via the first insulating member 520. The third column portion 513 and the second cover plate 120 are insulated from each other via the first insulating member 520. In addition, the third column portion 513 is connected to the connecting portion 620 of the second current collector 600.

[0104] It should be noted that the electrode terminal 510 , the first insulating member 520 , the second insulating member 530 and the sealing ring 540 together constitute the pole assembly 500 for electrically connecting the winding core 300 with an external circuit.

[0105] Further, the second immersion holes 610 are provided in multiple groups, and each group of second immersion holes 610 is arranged around the connecting portion 620. Each group of second immersion holes 610 includes multiple second immersion holes 610, and the multiple second immersion holes 610 in the same group are arranged at intervals in a direction away from the connecting portion 620.

[0106] At this time, the electrolyte stored in the liquid storage chamber 101 flows into each second liquid immersion hole 610 through the gap 640, enabling the end face of the winding core 300 to be evenly wetted, and the wetting effect is better.

[0107] Exemplarily, there are eight groups of second liquid immersion holes 610, and the eight groups of second liquid immersion holes 610 are evenly arranged around the connecting portion 620. Each group of second liquid immersion holes 610 includes three second liquid immersion holes 610, and the three second liquid immersion holes 610 in the same group are evenly arranged along the direction away from the connecting portion 620.

[0108] In summary, in the above-mentioned single cell 10, a liquid storage chamber 101 is formed between the winding core 300 and the inner wall of the housing 100, and the liquid storage chamber 101 can increase the space for accommodating the electrolyte. During long-term use, the electrolyte in the liquid injection channel 310 that is in direct contact with the winding core 300 gradually wears out. At this time, the electrolyte stored in the liquid storage chamber 101 can continuously flow into the liquid inlet hole 410 through the groove 430, and then be replenished into the liquid injection channel 310 to wet the winding core 300 from the inside of the winding core 300; at the same time, the electrolyte stored in the liquid storage chamber 101 can also flow into the first liquid immersion hole 421 through the groove 430, and flow into the second liquid immersion hole 610 through the gap 640, and wet the winding core 300 from the two end faces of the winding core 300 respectively, so that the winding core 300 can be fully wetted with the electrolyte, reduce or eliminate the "dead zone", thereby improving the cycle performance and safety performance of the single cell 10, and extending the service life of the single cell 10.

[0109] Please refer to Figure 9 , this embodiment also provides a battery pack, including the above-mentioned single cell 10.

[0110] In all the examples shown and described here, any specific value should be construed as merely exemplary, not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0111] It should be noted that: similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0112] The above-described embodiments merely represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A single cell battery, characterized in that: The single battery (10) has a first direction (Z) and comprises: A housing (100) comprising a plurality of side walls (110); A first cover plate (200) connected to one end of the housing (100) along the first direction (Z); A winding core (300) is arranged in the shell (100), at least one liquid storage cavity (101) is formed between the winding core (300) and the adjacent side wall (110), the winding core (300) is provided with a liquid injection channel (310) extending along the first direction (Z), and the liquid injection channel (310) is in communication with the liquid storage cavity (101); as well as A first current collecting member (400) is arranged in the shell (100) and is respectively connected to the winding core (300) and the first cover plate (200) along the first direction (Z); the first current collecting member (400) is provided with a liquid inlet hole (410) penetrating along the first direction (Z), and the liquid inlet hole (410) is communicated with the injection channel (310); a groove (430) is provided on a side of the first current collecting member (400) close to the first cover plate (200), and the groove (430) is recessed in a direction away from the first cover plate (200) along the first direction (Z), and the groove (430) is communicated with the liquid storage chamber (101) and the liquid inlet hole (410).

2. The single cell according to claim 1, characterized in that: The first current collecting member (400) is partially raised along the first direction (Z) to form a raised portion (420), and the raised portion (420) forms the groove (430) on the side of the first current collecting member (400) facing the first cover plate (200); the raised portion (420) is provided with a first immersion hole (421) penetrating along the first direction (Z), and the first immersion hole (421) is connected to the groove (430).

3. The single cell according to claim 2, characterized in that: The liquid inlet hole (410) corresponds to the liquid injection channel (310), and there are multiple protrusions (420). The multiple protrusions (420) are arranged around the liquid inlet hole (410) and are respectively extended in a direction away from the liquid inlet hole (410).

4. The single cell according to claim 3, characterized in that: Each of the protruding portions (420) is provided with a plurality of the first immersion holes (421), and the plurality of the first immersion holes (421) are arranged at intervals along the extension direction of the corresponding protruding portion (420).

5. The single cell according to claim 1, characterized in that: The shell (100) further comprises a second cover plate (120) connected to the plurality of side walls (110), the plurality of side walls (110) being arranged around the winding core (300), the second cover plate (120) being connected to one end of the side wall (110) away from the first cover plate (200) along the first direction (Z), and the liquid storage chamber (101) being formed between adjacent side walls (110) and the winding core (300).

6. The single cell according to claim 5, characterized in that: There are a plurality of liquid storage chambers (101), the plurality of liquid storage chambers (101) comprising a plurality of mutually connected liquid storage spaces (101a), the plurality of side walls (110) comprising a first side wall (111), a second side wall (112) and a third side wall (113), the first side wall (111) being connected to the second side wall (112), and the third side wall (113) being connected to the first side wall (111) and the second side wall (112) respectively; The winding core (300) is tangent to the first side wall (111), the second side wall (112) and the third side wall (113) respectively; the winding core (300) forms the liquid storage space (101a) with the first side wall (111) and the second side wall (112) respectively; the liquid storage space (101a) is formed between the first side wall (111) and the third side wall (113); and the liquid storage space (101a) is formed between the second side wall (112) and the third side wall (113).

7. The single cell according to claim 6, characterized in that: The maximum distance between the axis of the winding core (300) and the side wall (110) is not less than the diameter of the winding core (300).

8. The single cell according to claim 5, characterized in that: The single cell (10) further includes an electrode terminal (510) and a second current collector (600); The electrode terminal (510) is disposed through the second cover plate (120); The second current collecting member (600) is arranged in the shell (100), the second current collecting member (600) is connected to one end of the winding core (300) away from the first current collecting member (400) along the first direction (Z), the second current collecting member (600) is fixedly connected to the electrode terminal (510), and the second current collecting member (600) is provided with a second immersion hole (610) penetrating along the first direction (Z), and the second immersion hole (610) is connected to the liquid storage chamber (101).

9. The single cell according to claim 8, characterized in that: The single cell (10) further comprises a first insulating member (520), wherein the first insulating member (520) is arranged on a side of the second cover plate (120) facing the winding core (300) along the first direction (Z); The second current collecting member (600) comprises a connecting portion (620) and an immersion portion (630) surrounding the connecting portion (620), wherein the connecting portion (620) is connected to the electrode terminal (510), the second immersion hole (610) is provided on the immersion portion (630), a gap (640) is formed between the immersion portion (630) and the first insulating member (520), and the second immersion hole (610) is connected to the liquid storage chamber (101) through the gap (640).

10. The single cell according to claim 1, characterized in that: The first cover plate (200) is provided with a liquid injection hole (210) penetrating along the first direction (Z), the liquid injection hole (210) is arranged opposite to the liquid injection channel (310) along the first direction (Z), and the liquid injection hole (210) is connected to the groove (430) and the liquid injection channel (310).

11. A battery pack, characterized in that: It comprises the single cell (10) according to any one of claims 1 to 10.

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