Single battery and battery pack

Abstract

The utility model provides a single battery and a battery pack, and relates to the technical field of secondary batteries. Each single battery comprises a shell, an electrode assembly, an insulating layer and a bottom supporting plate; the electrode assembly is coated with the insulating layer, the insulating layer comprises a bottom insulating part, the bottom insulating part is located at one end of the electrode assembly in the first direction and attached to the electrode assembly, and a first through hole is formed in the bottom insulating part in a penetrating mode; the bottom supporting plate is connected with the side, away from the electrode assembly, of the bottom insulating part, a groove is formed in the side, facing the bottom insulating part, of the bottom supporting plate, a second through hole is formed in the groove bottom wall of the groove in a penetrating mode, the second through hole and the first through hole are arranged in a staggered mode in the second direction, and the groove is communicated with the first through hole and the second through hole to form a channel for electrolyte to flow. The electrolyte at the bottom of the shell can enter the electrode assembly through the channel to continuously infiltrate the electrode assembly, so that the problem that the electrode assembly cannot absorb the electrolyte at the bottom of the shell is solved, and the cycle capacity retention rate of the single battery is improved.

Description

Technical Field

[0001] This utility model relates to the field of secondary battery technology, and in particular to a single cell battery and a battery pack. Background Technology

[0002] The absorption and consumption of electrolyte by the electrode assembly have a significant impact on the performance of secondary batteries.

[0003] Currently, secondary batteries suffer from a problem where the electrode assembly cannot absorb the electrolyte from the bottom of the casing due to the barrier between the electrode assembly insulation layer and the bottom plate, which in turn leads to a decrease in cycle capacity retention. Utility Model Content

[0004] In order to solve the problems existing in the prior art, one of the objectives of this utility model is to provide a single-cell battery.

[0005] This utility model provides the following technical solution:

[0006] A single-cell battery having intersecting first and second directions, the single-cell battery comprising:

[0007] case;

[0008] Electrode assembly, disposed within the housing;

[0009] An insulating layer, disposed within the housing, covers the electrode assembly. The insulating layer includes a bottom insulating portion located at one end of the electrode assembly along the first direction, and the bottom insulating portion has a through-hole.

[0010] A bottom support plate is disposed inside the housing. The bottom support plate is connected to the side of the bottom insulating part away from the electrode assembly and is located between the housing and the bottom insulating part. The bottom support plate has a groove on the side facing the bottom insulating part. A second through hole is provided on the bottom wall of the groove. The second through hole and the first through hole are offset along the second direction. The groove communicates with the first through hole and the second through hole respectively.

[0011] As a further optional solution for the single cell, the number of the first through holes is multiple, and the multiple first through holes are arranged at intervals along the second direction;

[0012] The groove extends along the second direction, and the projection of the groove wall onto the bottom insulating portion along the first direction overlaps with the wall of the plurality of first through holes spaced apart along the second direction.

[0013] As a further optional solution for the single cell, the number of the second through holes is multiple, and the multiple second through holes are arranged at intervals along the second direction;

[0014] The groove extends along the second direction, and the projection of the groove wall onto the bottom insulating portion along the first direction overlaps with the wall of a plurality of second through holes spaced apart along the second direction.

[0015] As a further optional embodiment of the single cell, the single cell also has a third direction that intersects the first direction and the second direction in pairs;

[0016] The number of grooves is multiple, and the multiple grooves are arranged at intervals along the third direction;

[0017] The number of the first through holes is multiple sets, and the multiple sets of the first through holes are arranged at intervals along the third direction. The multiple sets of the first through holes are corresponding to the multiple grooves one by one. Each set of the first through holes includes multiple first through holes arranged at intervals along the second direction.

[0018] As a further optional solution for the single cell, the number of the second through holes is multiple sets, the multiple sets of the second through holes are arranged at intervals along the third direction, and the multiple sets of the second through holes are corresponding one-to-one with the multiple grooves, and the second through holes and the first through holes corresponding to the same groove are alternately arranged along the second direction.

[0019] As a further alternative to the single cell, the first through hole and the second through hole are staggered along the third direction.

[0020] As a further alternative to the single cell, the groove extends along the second direction through the surface of the base plate near the bottom insulation portion.

[0021] As a further alternative to the single cell, the thickness of the insulating layer along the first direction is less than the thickness of the base plate along the first direction.

[0022] As a further optional solution for the single battery, the single battery also includes a top cover, which is connected to the housing along the first direction and is disposed opposite to the bottom insulating portion along the first direction. A liquid injection hole is provided through the top cover, and the liquid injection hole communicates with the first through hole.

[0023] Another objective of this invention is to provide a battery pack.

[0024] This utility model provides the following technical solution:

[0025] A battery pack comprising the aforementioned individual battery cells.

[0026] The embodiments of this utility model have the following beneficial effects:

[0027] In the aforementioned single-cell battery, the electrode assembly, insulating layer, and bottom support plate are all housed within the casing. A first through-hole is formed through the bottom insulating portion of the insulating layer. A groove is formed on the side of the bottom support plate facing the bottom insulating portion, and a second through-hole is formed through the bottom wall of the groove. The first and second through-holes are connected through the groove, forming a channel for electrolyte flow. At this time, the electrolyte at the bottom of the casing can enter the electrode assembly through this channel, continuously wetting the electrode assembly and solving the problem that existing electrode assemblies cannot absorb the electrolyte at the bottom of the casing, thus improving the cycle capacity retention rate of the single-cell battery.

[0028] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This diagram shows an overall structural schematic of a single battery provided by an embodiment of the present invention;

[0031] Figure 2 An explosion diagram of a single-cell battery provided in an embodiment of the present invention is shown;

[0032] Figure 3 This diagram illustrates the structure of the insulating layer and the base plate in a single-cell battery according to an embodiment of the present invention.

[0033] Figure 4 The diagram shows a top view of an insulating layer and a bottom support plate in a single-cell battery according to an embodiment of the present invention;

[0034] Figure 5 It shows Figure 4 Sectional view along line AA;

[0035] Figure 6 It shows Figure 5 Enlarged view of point B in the middle;

[0036] Figure 7 It shows Figure 4 A partial schematic diagram of the cross-sectional view along the CC direction;

[0037] Figure 8 It shows Figure 4 A partial schematic diagram of the sectional view along the DD direction.

[0038] Explanation of key component symbols:

[0039] 100-Electrode assembly; 110-Electrode tab; 200-Insulating layer; 210-Bottom insulating part; 220-First through hole; 300-Bottom support plate; 310-Second through hole; 320-Groove; 400-Housing shell; 410-Receiving cavity; 500-Top cover; 510-Injection hole; 520-Electrode post; X-First direction; Y-Second direction; Z-Third direction. Detailed Implementation

[0040] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein 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 and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0041] It should be noted that when an element is said to be "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is said to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. Conversely, when an element is said to be "directly on" another element, there is no intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0042] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the template description is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0045] In related technologies, secondary batteries suffer from the problem that the electrode assembly 100 cannot absorb the electrolyte at the bottom of the casing 400 due to the obstruction of the electrolyte by the insulating layer 200 outside the electrode assembly 100 and the bottom plate 300, which in turn leads to a poor cycle capacity retention rate.

[0046] While increasing the amount of electrolyte injected and removing the insulation layer 200 can solve this problem to some extent, the former will increase costs and reduce the energy density of the secondary battery; the latter carries the risk of powder shedding and short circuits and salt bridge short circuits.

[0047] To address the aforementioned issues, this embodiment provides a single-cell battery. Please refer to the following: Figure 1 and Figure 2 The single cell has intersecting first direction X and second direction Y. The single cell includes a housing 400, an electrode assembly 100, an insulating layer 200, and a bottom support plate 300. The housing 400 has a receiving cavity 410 for containing electrolyte, and the electrode assembly 100, the insulating layer 200, and the bottom support plate 300 are all disposed in the receiving cavity 410.

[0048] Please combine Figure 3 The insulating layer 200 covers the electrode assembly 100 and includes a bottom insulating portion 210. The bottom insulating portion 210 is located at one end of the electrode assembly 100 along the first direction X, and is attached to the electrode assembly 100. The bottom insulating portion 210 has a through hole 220.

[0049] For example, the first direction X is the length direction of the single cell. The plane where the bottom insulating portion 210 is located is perpendicular to the first direction X, and the axial direction of the first through hole 220 is parallel to the first direction X. The first through hole 220 penetrates the bottom insulating portion 210 of the insulating layer 200 along the first direction X.

[0050] Furthermore, the bottom support plate 300 is connected to the side of the bottom insulating portion 210 opposite to the electrode assembly 100, and the bottom support plate 300 is located between the housing 400 and the bottom insulating portion 210. The bottom support plate 300 has a groove 320 on the side facing the bottom insulating portion 210, and a through second through hole 310 is provided on the bottom wall of the groove 320. The second through hole 310 communicates with the receiving cavity 410, and the second through hole 310 and the first through hole 220 are offset along the second direction Y. The groove 320 communicates with both the first through hole 220 and the second through hole 310.

[0051] For example, the second direction Y is the width direction of the single cell, and the second direction Y is perpendicular to the first direction X. The axial direction of the second through hole 310 is also parallel to the first direction X, and the second through hole 310 penetrates the bottom wall of the groove 320 along the first direction X.

[0052] In the aforementioned single-cell battery, the electrode assembly 100, the insulating layer 200, and the bottom support plate 300 are all disposed within the receiving cavity 410. The bottom insulating portion 210 of the insulating layer 200 has a first through hole 220. The bottom support plate 300 has a groove 320 on the side facing the bottom insulating portion 210. A second through hole 310 is provided through the bottom wall of the groove 320, communicating with the receiving cavity 410. The first through hole 220 and the second through hole 310 are connected through the groove 320, forming a channel for electrolyte flow. At this time, the electrolyte at the bottom of the casing 400 can enter the electrode assembly 100 through this channel, continuously wetting the electrode assembly 100, solving the problem that the existing electrode assembly 100 cannot absorb the electrolyte at the bottom of the casing 400, and improving the cycle capacity retention rate of the single-cell battery.

[0053] It should be noted that if the groove 320 is not provided on the side of the bottom support plate 300 facing the bottom insulation part 210, and only the first through hole 220 is provided on the bottom insulation part 210 and the second through hole 310 is provided on the bottom support plate 300, when the first through hole 220 and the second through hole 310 are misaligned, because the surfaces of the bottom insulation part 210 and the bottom support plate 300 are both smooth planes, the gap between the first through hole 220 and the second through hole 310 (i.e., the gap between the bottom insulation part 210 and the bottom support plate 300) is squeezed due to the gravity of the electrode assembly 100, resulting in an unsatisfactory seepage effect and failing to effectively solve the problem that the existing electrode assembly 100 cannot absorb the electrolyte at the bottom of the housing 400. Alternatively, when the first through hole 220 and the second through hole 310 are aligned, although the seepage effect is good, there is a risk of powder shedding, short circuit, and salt bridge overlap, which is not conducive to the long-term stable operation of the single cell.

[0054] In contrast, the single cell provided in this application not only effectively connects the first through hole 220 and the second through hole 310 by setting a groove 320 on the bottom plate 300 to ensure good liquid seepage effect, but also makes the second through hole 310 and the first through hole 220 offset along the second direction Y, which can greatly reduce the risk of powder shedding short circuit and salt bridge overlap, and is conducive to the long-term stable operation of the single cell.

[0055] Please refer to the following: Figure 2 and Figure 3 In some embodiments, the aforementioned single battery cell also includes a top cover 500.

[0056] The top cover 500 is connected to the housing 400 along the first direction X, and the top cover 500 covers the receiving cavity 410. The top cover 500 is disposed opposite to the bottom insulating part 210 along the first direction X. A liquid injection hole 510 is provided through the top cover 500, and the liquid injection hole 510 communicates with the first through hole 220.

[0057] Specifically, the top cover 500 and the bottom insulating portion 210, which are disposed opposite to each other along the first direction X, are located at both ends of the electrode assembly 100 along the first direction X. The insulating layer 200 only covers the end of the electrode assembly 100 along the first direction X facing the bottom insulating portion 210, and the various sides of the electrode assembly 100 parallel to the first direction X. At the same time, the end of the electrode assembly 100 along the first direction X facing the top cover 500 is exposed and is provided with a tab 110. Correspondingly, a pole post 520 is provided on the top cover 500, and the pole post 520 is welded to the tab 110 and electrically connected.

[0058] Furthermore, the axial direction of the injection hole 510 is parallel to the first direction X, and the injection hole 510 penetrates the top cover 500 along the first direction X. Since the top cover 500 is directly placed on the receiving cavity 410, the injection hole 510 penetrating the top cover 500 is directly connected to the receiving cavity 410, and then indirectly connected to the first through hole 220 through the receiving cavity 410.

[0059] Please refer to the following: Figure 4 , Figure 5 and Figure 6 In some embodiments, there are multiple first through holes 220, and the multiple first through holes 220 are arranged at intervals along the second direction Y.

[0060] Meanwhile, the groove 320 extends along the second direction Y, and the projection of the groove wall of the groove 320 onto the bottom insulating portion 210 along the first direction X overlaps with the hole walls of a plurality of first through holes 220 arranged at intervals along the second direction Y.

[0061] Understandably, providing multiple first through holes 220 on the bottom insulating portion 210 facilitates the smooth flow of electrolyte in the groove 320 into the inner side of the insulating layer 200, thereby enabling better wetting of the electrode assembly 100.

[0062] Furthermore, the projection of the bottom of the groove 320 onto the bottom insulating portion 210 along the first direction X overlaps with the wall of the first through hole 220, meaning the groove 320 and the first through hole 220 are aligned along the first direction X. Based on this, by arranging multiple first through holes 220 at intervals along the second direction Y, and simultaneously extending the groove 320 along the second direction Y, it is possible to connect multiple first through holes 220 with one groove 320, simplifying the structure of the bottom support plate 300.

[0063] In other embodiments, the groove 320 may also be curved or other shapes, as long as it can connect multiple first through holes 220 at the same time. This embodiment does not limit this.

[0064] To better guide the electrolyte into the first through-hole 220, the groove 320 can be configured as an inverted trapezoid, meaning that the width of the groove 320 gradually decreases along the first direction X from near the insulating layer 200 to away from the insulating layer 200. This facilitates the rapid entry of the electrolyte from the second through-hole 310 into the first through-hole.

[0065] Please combine Figure 7 Furthermore, the diameter of the first through hole 220 is D1, and the width of the groove 320 is W, satisfying 1mm≤D1≤10mm, and W>D1.

[0066] In other words, the width of the groove 320 is greater than the diameter of the first through hole 220. At this time, the projection of the bottom of the groove 320 along the first direction X onto the bottom insulating portion 210 completely covers the wall of the first through hole 220. The first through hole 220 can be fully utilized, which facilitates the smoother flow of the electrolyte within the groove 320 into the inner side of the insulating layer 200, thereby better wetting of the electrode assembly 100.

[0067] Optionally, the diameter of the first through hole 220 can be 1 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm or any value between 1 mm and 10 mm.

[0068] Please refer to it again. Figure 3 In some embodiments, there are multiple second through holes 310, and the multiple second through holes 310 are arranged at intervals along the second direction Y.

[0069] Meanwhile, the groove 320 extends along the second direction Y, and the projection of the groove wall of the groove 320 onto the bottom insulating portion 210 along the first direction X overlaps with the hole walls of a plurality of second through holes 310 spaced apart along the second direction Y.

[0070] Understandably, providing multiple second through holes 310 on the bottom plate 300 facilitates the smooth flow of electrolyte from the bottom of the housing 400 into the groove 320, and then into the inner side of the insulating layer 200 through the first through hole 220, thereby enabling better wetting of the electrode assembly 100.

[0071] Furthermore, the projection of the bottom of the groove 320 onto the bottom insulating portion 210 along the first direction X overlaps with the wall of the second through hole 310, meaning that the groove 320 and the second through hole 310 are aligned along the first direction X. Based on this, by arranging multiple second through holes 310 at intervals along the second direction Y, and simultaneously extending the groove 320 along the second direction Y, it is possible to connect multiple second through holes 310 with one groove 320, which also simplifies the structure of the bottom support plate 300.

[0072] Please combine Figure 8 Furthermore, the diameter of the second through hole 310 is D2, and the width of the groove 320 is W, satisfying 1mm≤D2≤10mm, and W>D2.

[0073] In other words, the width of the groove 320 is greater than the diameter of the second through hole 310. At this time, the projection of the bottom of the groove 320 along the second direction Y onto the bottom insulating portion 210 completely covers the projection of the hole wall of the second through hole 310 along the second direction Y onto the bottom insulating portion 210. The second through hole 310 can be fully utilized, which facilitates the smoother flow of electrolyte from the bottom of the housing 400 into the groove 320, and then into the inner side of the insulating layer 200 through the first through hole 220, thereby better wetting the electrode assembly 100.

[0074] Optionally, the diameter of the second through hole 310 can be 1 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm or any value between 1 mm and 10 mm.

[0075] Please refer to it again. Figure 3 Furthermore, the groove 320 extends along the second direction Y through the surface of the bottom support plate 300 near the bottom insulation portion 210.

[0076] At this time, the two ends of the groove 320 along the second direction Y are respectively connected to the receiving cavity 410. The electrolyte at the bottom of the housing 400 can also flow into the groove 320 from both ends, and then flow into the inner side of the insulating layer 200 through the first through hole 220. As a result, more electrolyte flows into the groove 320, resulting in a better wetting effect on the electrode assembly 100.

[0077] In some embodiments, the aforementioned single cell also has a third direction Z that intersects the first direction X and the second direction Y in pairs.

[0078] At the same time, there are multiple grooves 320, and the multiple grooves 320 are arranged at intervals along the third direction Z.

[0079] Accordingly, there are multiple sets of first through holes 220. The multiple sets of first through holes 220 are arranged at intervals along the third direction Z, and the multiple sets of first through holes 220 are corresponding one-to-one with multiple grooves 320. Each set of first through holes 220 includes multiple first through holes 220 arranged at intervals along the second direction Y.

[0080] Understandably, multiple sets of first through holes 220 are arranged at intervals along the third direction Z, and multiple first through holes 220 in each set of first through holes 220 are arranged at intervals along the second direction Y, that is, the array of first through holes 220 is arranged on the bottom insulating portion 210. Based on this, multiple grooves 320 are provided in a one-to-one correspondence with multiple sets of first through holes 220, and the grooves 320 are connected to multiple first through holes 220 in the corresponding set of first through holes 220, so that the electrolyte entering the grooves 320 can flow evenly into the inner side of the insulating layer 200 through each first through hole 220, thereby evenly wetting the electrode assembly 100 and preventing the electrode assembly 100 from having insufficient local absorption of electrolyte.

[0081] For example, the third direction Z is the thickness direction of a single cell, and the third direction Z is perpendicular to both the first direction X and the second direction Y.

[0082] Furthermore, there are multiple sets of second through holes 310. The multiple sets of second through holes 310 are arranged at intervals along the third direction Z, and the multiple sets of second through holes 310 are corresponding one-to-one with multiple grooves 320. The second through holes 310 and the first through holes 220 corresponding to the same groove 320 are arranged alternately along the second direction Y.

[0083] Similarly, multiple sets of second through holes 310 are arranged at intervals along the third direction Z, corresponding one-to-one with multiple grooves 320. Multiple second through holes 310 in the same group corresponding to the same groove 320 are arranged at intervals along the second direction Y, i.e., the second through holes 310 are arrayed on the bottom support plate 300. Based on this, the multiple sets of second through holes 310 communicate with their respective corresponding grooves 320, allowing the electrolyte at the bottom of the housing 400 to flow evenly into the grooves 320 through each second through hole 310. This also facilitates the even flow of electrolyte into the inner side of the insulating layer 200, thereby evenly wetting the electrode assembly 100 and preventing insufficient localized electrolyte absorption in the electrode assembly 100.

[0084] Furthermore, since the second through hole 310 and the first through hole 220 corresponding to the same groove 320 are arranged alternately, the electrolyte at the bottom of the housing 400 can flow into the groove 320 through the first through hole 220 via the shortest path after flowing into the groove 320 through the second through hole 310, thereby improving the wetting effect on the electrode assembly 100.

[0085] Please refer to it again. Figure 6Furthermore, the diameter of the first through hole 220 is D1, the diameter of the second through hole 310 is D2, and the distance between the center of the first through hole 220 and the center of the adjacent second through hole 310 along the second direction Y is L, satisfying L>(D1+D2) / 2.

[0086] Since the distance between the center of the first through hole 220 and the center of the adjacent second through hole 310 along the second direction Y is greater than the sum of the radii of the first through hole 220 and the second through hole 310, it can be ensured that the first through hole 220 and the second through hole 310 are completely misaligned along the second direction Y, reducing the risk of powder shedding short circuits and salt bridge overlaps.

[0087] In some embodiments, the first through hole 220 and the second through hole 310 are staggered along the third direction Z.

[0088] Since the width of the groove 320 is greater than the diameter of the first through hole 220 and also greater than the diameter of the second through hole 310, under the premise that the groove 320 and the first through hole 220, and the groove 320 and the second through hole 310 are aligned along the first direction X respectively, the first through hole 220 and the second through hole 310 are staggered along the third direction Z, which can make full use of the space in the width direction of the groove 320. At this time, the first through hole 220 and the second through hole 310 are both staggered along the second direction Y and staggered along the third direction Z, which can further reduce the risk of powder shedding short circuits and salt bridging.

[0089] Please refer to it again. Figure 8 Furthermore, the thickness of the insulating layer 200 along the first direction X is less than the thickness of the base plate 300 along the first direction X.

[0090] The insulation layer 200 has a thickness of H1 along the first direction X, and the base plate 300 has a thickness of H2 along the first direction X, satisfying H1 < H2. Furthermore, 0.01 mm ≤ H1 ≤ 1 mm, and 1 mm ≤ H2 ≤ 5 mm.

[0091] Understandably, the width of the gap between the electrode assembly 100 and the bottom inner wall of the housing 400 is limited. When the sum of the thickness of the insulating layer 200 and the thickness of the base plate 300 is not greater than the width of this gap, making the thickness of the base plate 300 greater than the thickness of the insulating layer 200, and allocating more of the limited space to the base plate 300, ensures that the base plate 300 has sufficient strength.

[0092] Optionally, the thickness of the insulating layer 200 can be any value between 0.01mm, 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm, or 0.01mm to 1mm. The thickness of the base plate 300 can be any value between 1mm, 2mm, 3mm, 4mm, 5mm, or 1mm to 5mm.

[0093] Please refer to it again. Figure 6 Furthermore, the depth of the groove 320 is T, which satisfies 0.1mm ≤ T ≤ 1mm. In addition, T < H2.

[0094] Understandably, ensuring that the depth of the groove 320 is not less than 0.1 mm ensures that the electrolyte flows smoothly within the groove 320. Conversely, ensuring that the depth of the groove 320 is not greater than 1 mm prevents the area of ​​the base plate 300 corresponding to the bottom of the groove 320 from becoming too thin, thus ensuring that the base plate 300 has sufficient structural strength.

[0095] Optionally, the depth of the groove 320 can be 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm or any value between 0.1mm and 1mm.

[0096] In summary, the aforementioned single-cell battery, by providing a first through-hole 220 through the bottom insulating portion 210 of the insulating layer 200, a groove 320 on the side of the bottom support plate 300 facing the bottom insulating portion 210, and a second through-hole 310 through the bottom wall of the groove 320, allows the receiving cavity 410 to communicate with the inner region of the insulating layer 200 sequentially through the second through-hole 310, the groove 320, and the first through-hole 220, forming a channel for electrolyte flow. At this time, the electrolyte at the bottom of the casing 400 can enter the electrode assembly 100 through this channel, continuously wetting the electrode assembly 100, solving the problem that the existing electrode assembly 100 cannot absorb the electrolyte at the bottom of the casing 400, and improving the cycle capacity retention rate of the single-cell battery.

[0097] For example, the assembly process of the above-mentioned single battery cell is as follows:

[0098] The first step is to weld the electrode assembly 100 to the top cover 500, specifically by welding and fixing the tab 110 on the electrode assembly 100 to the pole 520 on the top cover 500.

[0099] The second step involves using materials such as polyethylene ester and polyvinyl chloride to make an insulating layer 200. A first through hole 220 is opened in the bottom insulating part 210 of the insulating layer 200, and then the insulating layer 200 is wrapped around the electrode assembly 100.

[0100] The insulation layer 200 has a thickness of 0.2 mm. The diameter of the first through hole 220 is 2 mm, and the first through holes 220 are arranged in a rectangular array with a longitudinal and transverse spacing of 8 mm.

[0101] The third step involves fabricating a base plate 300 using materials such as polyethylene terephthalate (PE) and polyvinyl chloride (PVC). A second through hole 310 is formed on the base plate 300, and a strip-shaped groove 320 is provided at the position corresponding to the second through hole 310. The base plate 300 is fixed to the outside of the insulating layer 200 by heat fusion and is located at the bottom of the electrode assembly 100, with the side of the base plate 300 having the groove 320 facing the insulating layer 200. The first through hole 220 and the second through hole 310 are not aligned, but are in a straight line, and the groove 320 connects the first through hole 220 and the second through hole 310.

[0102] The base plate 300 has a thickness of 2mm. The diameter of the second through hole 310 is 2mm, and the second through holes 310 are arranged in a rectangular array with a longitudinal and transverse spacing of 8mm. The groove 320 has a depth of 0.2mm and a width of 4mm. The groove 320 is arranged along the second direction Y, connecting the second through holes 310 arranged at intervals along the second direction Y in series.

[0103] The fourth step is to install the top cover 500, the core, the insulation layer 200, and the bottom support plate 300 into the housing 400, and weld them together at the gap between the top cover 500 and the housing 400 to form a seal.

[0104] The fifth step is to inject electrolyte into the receiving cavity 410 through the injection hole 510.

[0105] This embodiment also provides a battery pack, including the above-mentioned single battery cell.

[0106] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limitations; therefore, other examples of exemplary embodiments may have different values.

[0107] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0108] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A single cell, characterized by, The monomer battery has a first direction (X) and a second direction (Y) intersecting each other, and comprises: a shell (400); an electrode assembly (100) arranged in the shell (400); an insulation layer (200) arranged in the shell (400), the insulation layer (200) covering the electrode assembly (100), the insulation layer (200) comprising a bottom insulation part (210) located at one end of the electrode assembly (100) along the first direction (X), the bottom insulation part (210) being provided with a first through hole (220) penetrating therethrough; and a bottom supporting plate (300) arranged in the shell (400), the bottom supporting plate (300) being connected to a side of the bottom insulation part (210) away from the electrode assembly (100) and located between the shell (400) and the bottom insulation part (210), the bottom supporting plate (300) being provided with a groove (320) on a side thereof facing the bottom insulation part (210), the groove (320) being provided with a second through hole (310) penetrating therethrough on a groove bottom wall thereof, the second through hole (310) being arranged in a staggered manner with the first through hole (220) along the second direction (Y), and the groove (320) being in communication with the first through hole (220) and the second through hole (310) respectively.

2. The cell according to claim 1, wherein The number of the first through holes (220) is multiple, and the multiple first through holes (220) are arranged in a spaced manner along the second direction (Y); the groove (320) is arranged in an extending manner along the second direction (Y), and a projection of a groove wall of the groove (320) on the bottom insulation part (210) along the first direction (X) overlaps with hole walls of the multiple first through holes (220) arranged in a spaced manner along the second direction (Y).

3. The cell according to claim 1, wherein The number of the second through holes (310) is multiple, and the multiple second through holes (310) are arranged in a spaced manner along the second direction (Y); the groove (320) is arranged in an extending manner along the second direction (Y), and a projection of a groove wall of the groove (320) on the bottom insulation part (210) along the first direction (X) overlaps with hole walls of the multiple second through holes (310) arranged in a spaced manner along the second direction (Y).

4. The cell according to claim 1, wherein The monomer battery also has a third direction (Z) intersecting each of the first direction (X) and the second direction (Y); The number of the grooves (320) is multiple, and the multiple grooves (320) are arranged in a spaced manner along the third direction (Z); The number of the first through holes (220) is multiple groups, the multiple groups of the first through holes (220) are arranged in a spaced manner along the third direction (Z), and the multiple groups of the first through holes (220) are arranged in a one-to-one correspondence with the multiple grooves (320), each group of the first through holes (220) comprising multiple first through holes (220) arranged in a spaced manner along the second direction (Y).

5. The cell according to claim 4, wherein The second through holes (310) are arranged in multiple groups, the multiple groups of the second through holes (310) are arranged at intervals along the third direction (Z), and the multiple groups of the second through holes (310) are arranged one by one with the multiple grooves (320). The second through holes (310) corresponding to the same groove (320) and the first through holes (220) are arranged alternately along the second direction (Y).

6. The cell according to claim 4, wherein The first through holes (220) and the second through holes (310) are arranged alternately along the third direction (Z).

7. The cell according to claim 1, wherein The groove (320) penetrates the surface of the bottom supporting plate (300) close to the bottom insulation part (210) along the second direction (Y).

8. The cell according to claim 1, wherein The thickness of the insulation layer (200) along the first direction (X) is less than the thickness of the bottom supporting plate (300) along the first direction (X).

9. The cell of claim 1 wherein, The single battery further comprises a top cover (500) connected with the shell (400) along the first direction (X), the top cover (500) is arranged opposite to the bottom insulation part (210) along the first direction (X), and a liquid injection hole (510) is arranged through the top cover (500), the liquid injection hole (510) communicates with the first through hole (220).

10. A battery pack, characterized by, The single battery of any one of claims 1-9 is included.

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