Battery cell, battery device and electrical device

Abstract

Battery cell, characterized in that it comprises: a housing with a receiving cavity; an electrode assembly provided in the receiving cavity, the electrode assembly being constructed as a stacked cell, the stacked cell comprising a plurality of positive electrodes, a plurality of negative electrodes, and a separator, the plurality of positive electrodes and the plurality of negative electrodes being stacked in sequence along a thickness direction of the electrode assembly, the separator being provided between each adjacent positive electrode and negative electrode and on the outside of the outermost positive electrode and / or negative electrode along the thickness direction of the electrode assembly; the thickness direction being parallel to the direction in which the positive electrodes and the negative electrodes are stacked; a first tab provided at one end of the electrode assembly in a longitudinal direction; wherein the electrode assembly has a first side surface and a second side surface opposite each other in a width direction, and the longitudinal direction, the thickness direction, and the width direction of the electrode assembly are perpendicular to each other, wherein the battery cell further comprises a first tape, wherein at least one first tape is provided, and the first tape is adhered to the first side surface, the total length of the first tape along the longitudinal direction of the electrode assembly is “D1”, the dimension of an end of the separator that extends beyond the end of the same side of the negative electrode along the width direction of the electrode assembly is “h”, wherein the following is satisfied: 15 mm 2 ≤ h * D1 ≤ 1800 mm 2 .

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries or accumulators, in particular a battery cell, a battery device and an electrical device. BACKGROUND

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles have become an important part of the sustainable development of the automotive industry due to their advantages of energy conservation and environmental protection. Battery technology is a key factor in the development of electric vehicles.

[0003] During battery use, battery reliability is an issue that cannot be ignored. Therefore, improving battery reliability is a technical problem that needs to be solved at present. SUMMARY OF THE UTILITY MODEL

[0004] The present application provides a battery cell, a battery device, and an electrical appliance, wherein the reliability of the battery cell is improved.

[0005] To achieve the above problem, the main technical solutions adopted by the present application include the following: According to the first aspect, an embodiment of the present application provides a battery cell comprising a housing, an electrode assembly, a first tab, and a first band, wherein the housing has a receiving cavity; the electrode assembly is provided in the receiving cavity, and the electrode assembly is constructed as a stacked cell, the stacked cell including a plurality of positive electrodes, a plurality of negative electrodes, and a separator, wherein the plurality of positive electrodes and the plurality of negative electrodes are stacked in sequence along a thickness direction of the electrode assembly, the separator is provided between each adjacent positive electrode and negative electrode and on the outside of the outermost positive electrode and / or negative electrode along the thickness direction of the electrode assembly;the thickness direction is parallel to the direction in which the positive electrodes and the negative electrodes are stacked; the first tab is provided at one end of the electrode assembly in a longitudinal direction; wherein the electrode assembly has a first side surface and a second side surface that are opposite to each other in a width direction, and the longitudinal direction, the thickness direction, and the width direction of the electrode assembly are perpendicular to each other, wherein at least one first tape is provided, the first tape being adhered to the first side surface, the total length of the first tape along the longitudinal direction of the electrode assembly being "D1", the dimension of an end of the separator that extends beyond the end of the same side of the negative electrode along the width direction of the electrode assembly being "h", wherein the following is satisfied: 15 mm; 2 ≤ h * D1 ≤ 1800 mm 2 .

[0006] In the battery cell according to the embodiment of the present application, a separator is provided between each adjacent positive electrode and negative electrode and on the outside of the outermost positive electrode and / or negative electrode along the thickness direction of the electrode assembly, which can effectively isolate the positive electrodes and the negative electrodes and reduce the possibility of a short circuit within the battery; After the cells are stacked, the plurality of electrodes and the separator are in a loose state, and the first band provided on the side can bind the stacked positive electrodes, negative electrodes, and the separator together, reduce the looseness of the electrode assembly, and thereby reduce the local lithium-ion transfer impedance, which is beneficial for lithium-ion transfer.By controlling the sum of the dimensions of the first band and the dimension of an end of the separator extending beyond the end on the same side of the negative electrode to conform to the above range, the first band is used to bond the electrode assembly, which is beneficial for lithium ion transfer during subsequent charging and discharging.On the one hand, it prevents the tape from being too narrow and prevents the separator from being too small in the direction of the negative electrode, thereby reducing the probability of the separator being kinked when the tape is fixed, thereby reducing the probability of short circuit after the separator is kinked, and ensuring that the tape exerts sufficient binding force on the electrode assembly; On the other hand, it prevents the tape from being too wide and the separator from being too large in the direction of the negative electrode, thereby reducing the probability of simple positional deviation when the tape is bonded, reducing the tensile force of the tape on the separator, and reducing the risk of the separator being kinked due to the tape being too narrow, thereby improving the reliability of the battery.

[0007] According to the second aspect, the embodiment of the present application provides a battery device including a battery cell as described in the above embodiment.

[0008] According to the third aspect, the embodiment of the present application provides an electrical device including a battery device as described in the above embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] To more clearly illustrate the embodiments of the present application or the technical solution in the prior art, the following briefly presents the drawings required for describing the specific implementation or prior art. Obviously, the drawings described below represent some embodiments of the present application. Those skilled in the art can also obtain other drawings based on these drawings without any creative effort. Fig. 1 is a schematic diagram showing the overall structure of an embodiment of the present application; Fig. 2 is a schematic diagram showing the overall structure of the electrode assembly according to an embodiment of the present application; Fig. 3 is an enlarged structural diagram of one end of the electrode assembly according to an embodiment of the present application; Fig. 4 is a front view of one end of the electrode assembly according to an embodiment of the present application; Fig. 5 is a partially enlarged graphical structural representation according to Fig. 4; Fig. 6 is another partially enlarged graphical structural representation according to Fig. 4; Fig. 7 is a plan view of the electrode assembly according to an embodiment of the present application; Fig. 8 is a front view of one end of the electrode assembly according to an embodiment of the present application; Fig. 9 is a front cross-sectional view of the electrode assembly according to an embodiment of the present application. In the figures:

[0010] 100: Housing; 101: Receptacle cavity; 110: End cap; 111: First end cap; 111a: First terminal arrangement; 112: Second end cap; 112a: Second terminal arrangement; 120: Housing body; 200: Electrode assembly; 201: Stacked cell; 210: Positive electrode; 220: Negative electrode; 230: Separator; 201: First side surface; 202: Second side surface; 203: Third surface; 204: Fourth side surface; 300: First Volume; 301: First Section; 302: Second Section; 303: Third Section; 304: Fourth Section; 400: Second volume; 500: First tab; 600: Second tab; 700: Negative electron unit; 720: First separator; 730: Second separator; X: Length direction; Y: Width direction; Z: Thickness direction. DETAILED DESCRIPTION OF EMBODIMENTS

[0011] To clarify the purpose, technical solution, and advantages of the embodiments of the present application, the technical solution in the embodiment of the present application is described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are a part of the embodiments of the present application and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of the present application.

[0012] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used in the specification of this application in the application text are for the sole purpose of describing specific embodiments and are not intended to limit this application. The terms "comprising," "including," and "having" in the application text and claims of this application and the above-mentioned drawings, and any variations thereof, are intended to cover non-exclusive inclusions. The terms "first," "second," etc.in the application text and claims of the present application or the above-mentioned drawings are used to distinguish different objects rather than to describe a specific order or primary and secondary relationship.

[0013] Reference to an "embodiment" in this application means that the specific features, structures, or characteristics described in connection with the embodiment may be included in at least one embodiment of this application. The phrase used in various places throughout the application text does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It will be recognized explicitly and implicitly by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0014] It should be noted, unless otherwise clearly specified and limited, that in the description of this application, the terms "installation," "interconnection," "connection," and "attachment" should be understood in a broad sense. It may, for example, be a fixed connection, a detachable connection, or a one-piece connection; it may be directly connected or indirectly connected via an intermediate medium, or it may be the internal connection of two elements. Those skilled in the art may understand the specific meanings of the above terms in this application according to the specific circumstances.

[0015] The term "and / or" in this application is merely a description of the association relationship of the associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the symbol " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0016] "A plurality of" or "multiple" in this application refers to more than two (including two), similarly, "multiple groups" refers to more than two groups (including two groups) and "multiple sheets" refers to more than two sheets (including two sheets).

[0017] As an example, a battery cell includes a cell with a positive electrode and a negative electrode as electrochemical material carriers, a separator for separating the positive electrode and the negative electrode to prevent short circuits, an electrolyte as an ion transport carrier, a casing to achieve structural protection, and a terminal to achieve connection to an external circuit.

[0018] According to some embodiments, the positive electrode includes a positive current collector, wherein the positive current collector has a plurality of surfaces, at least one of which is provided with a positive active material.

[0019] As an example, the positive active material is located on the surface of the positive current collector along its own thickness direction.

[0020] As an example, the positive current collector may be a metal foil or a composite current collector. When the positive current collector includes a metal foil, at least one of aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium may be used. When the positive current collector includes a composite current collector, the composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver and a silver alloy, etc.) on a polymer material substrate (such as a substrate made of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0021] As an example, the positive active material includes, but is not limited to, the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. Other conventional materials that can be used as positive active materials for batteries can also be used.

[0022] According to some embodiments, the negative electrode includes a negative current collector and a negative active material. The negative current collector includes a metal foil or a composite current collector. When the negative current collector includes a metal foil, at least one of aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium can be used.

[0023] As an example, the negative active material is provided on the surface of the negative current collector along its thickness direction.

[0024] As an example, the negative active material includes, but is not limited to, the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate. Other conventional materials known in the art that can be used as negative active materials for batteries may also be used. The silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys, but the present application is not limited to these materials.These negative active materials can be used alone or in a combination of two or more.

[0025] According to some embodiments, the separator may be selected from any known separator having a porous structure and good chemical stability and mechanical stability.

[0026] As an example, the main material of the separator includes at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramics. The separator can be a single-layer film or a multi-layer composite film without any particular restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different without any particular restrictions. The insulating component can be a single component located between the positive electrode and the negative electrode, or it can be attached to the surface of the positive electrode and the negative electrode.

[0027] According to some embodiments, the positive electrode, the negative electrode, and the separator form a stacked structure. The stacked structure refers to the stacking of the positive electrode, the negative electrode, and the separator of the separate sheet structure; the positive electrode and the negative electrode are both discontinuous, while the adjacent layers are discontinuous; In addition, the separator according to the present application may also be a separate sheet and be discontinuous; According to another embodiment, the separator may also be continuous, while the positive electrode and the negative electrode may be discontinuous, thereby forming a Z-shaped stacked structure.

[0028] According to some embodiments, the housing includes at least one of a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film. The housing can encapsulate components such as the positive electrode, the negative electrode, and the separator.

[0029] According to some embodiments, the housing comprises an end cap and a housing body, wherein the housing is provided with an opening, and the end cap closes the opening to form an enclosed space for receiving substances, such as electrode assemblies and electrolytes. The housing body may be provided with one or more openings. Furthermore, one or more end caps may be provided, wherein the end caps may also be used to provide other structural parts of the battery, such as electrode terminals, pressure relief mechanisms, fluid injection holes, etc., which are not limited in the present application.

[0030] According to some embodiments, at least one electrode terminal is provided on the housing, wherein the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal may play a role in circuit transmission, and the electrode terminal may subsequently be connected to a busbar to establish an electrical connection between multiple battery cells. The electrode terminal may be provided on the end cap or on the housing body.

[0031] Batteries face several challenges in practical applications, among which separator folding is a relatively common problem. Separator folding not only affects battery performance and safety but can also lead to serious consequences, such as short circuits and thermal runaway.

[0032] In the stacked battery, multiple electrodes are stacked in layers. Compared with the case where the conventional battery is covered by the separator, the battery is less restricted. The side of the battery must be fixed with tape. When the tape is fixed, the separator is in a multi-layered scattered state, so the separator is likely to fold. After the separator is folded and buckled, the electrodes may fall off, resulting in uneven distribution of the battery's internal resistance. In places with low internal resistance, the battery may be locally overcharged or overdischarged during cycling, affecting the battery's consistency and cycle performance. In severe cases, this can cause serious consequences, such as short circuit and thermal runaway of the battery.Moreover, after folding and bending the separator, direct contact between the positive electrode and the negative electrode may also be caused to cause a short circuit.

[0033] In view of this, the embodiment of the present application provides a battery cell to improve the reliability of the battery. Fig. 1, Fig. 2, Fig. 3 and Fig. 9, the battery cell includes a housing 100, an electrode assembly 200, a first tab 500, and a first band 300.

[0034] The housing 100 has a receiving cavity 101, with the electrode assembly 200 provided in the receiving cavity 101. It can be appreciated that the housing 100 can provide structural protection for the electrode assembly 200 in the receiving cavity 101, helping to improve the reliability of the battery.

[0035] The electrode assembly 200 is constructed as a stacked cell 201 including a positive electrode 210, a negative electrode 220, and a separator 230. The positive electrodes 210 and the negative electrodes 220 may be plural and are stacked sequentially along the thickness direction "Z" of the electrode assembly 200. It can be appreciated that sequential stacking means that an alternating arrangement of a positive electrode, a negative electrode, another positive electrode, and another negative electrode is provided sequentially along the thickness of the electrode assembly 200, with no limitation on the number of stacked positive electrodes and negative electrodes. Stacking a plurality of positive electrodes 210 and negative electrodes 220 helps improve the power density of the battery.

[0036] As an example, the stacked cell 201 refers to the stacking of a plurality of independent sheet-shaped positive electrodes 210 and negative electrodes 220, wherein each positive electrode 210 and each negative electrode 220 are independent of each other.

[0037] A separator 230 is provided between adjacent positive electrodes 210 and negative electrodes 220 and on the outside of the outermost positive electrode 210 and / or negative electrode 220 along the thickness direction "Z" of the electrode assembly 200. It can be seen that the separator 230, as an electronic insulator, effectively prevents the risk of an internal short circuit of the battery when the battery is operating normally.

[0038] The first tab 500 is provided at one end of the electrode assembly 200 in the longitudinal direction "X." The first tab 500 can play the role of transmitting the cell's internal current and can be electrically connected to the corresponding electrode terminal. The material of the first tab 500 can be the same as the material of the current collector, specifically at least one of aluminum with silver plating on the surface, stainless steel with silver plating on the surface, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium.

[0039] As an example, the material of the first tape 300 may be a polyimide film (PI film), an acrylimide film (PPA film), or a polyethylene film.

[0040] The electrode assembly 200 has a first side surface 201 and a second side surface 202 opposite each other in the width direction "Y," with at least one first band 300 bonded to the first side surface 201. It can be appreciated that multiple first bands 300 can be used to collectively fix the electrode assembly 200, thereby ensuring the bonding effect of the electrode assembly 200 and reducing the likelihood of cell loosening.

[0041] In Fig. 7, along the longitudinal direction “X” of the electrode assembly 200, the total length of the first band 300 is “D1”, and along the width direction “Y” of the electrode assembly 200, the dimension of one end of the separator 230 that extends beyond the end on the same side of the negative electrode 220 is “h”, wherein the following is satisfied: 15 mm 2 ≤ h * D1 ≤ 1800 mm 2. Consequently, the electrode assembly 200 can be bonded, the probability of looseness between the positive electrode 210, the negative electrode 220, and the separator 230 can be reduced, the lithium ion transfer effect between the positive electrode 210, the negative electrode 220, and the separator 230 can be ensured, and the separator 230 can be prevented from being folded and buckled, thereby reducing the risk of the electrode falling and the positive and negative electrodes short-circuiting.

[0042] It should be noted that when the first band 300 is single, the total length of the first band 300 refers to the dimension of the single first band 300 along the longitudinal direction "X" of the electrode assembly 200; when the first band 300 is multiple, the total length of the first band 300 refers to the sum of the dimensions of multiple first bands 300 along the longitudinal direction "X" of the electrode assembly 200.

[0043] According to the above embodiment, by controlling the sum of the dimensions of the plurality of first bands 300 and the dimension of one end of the separator 230 that exceeds the end on the same side of the negative electrode 220 to correspond to the above range, on the one hand, when the band is fixed, the pressure area of ​​the separator 230 can be increased, the pressure on the separator 230 can be reduced, and the probability of folding and buckling at the edge of the separator 230 can be reduced, thereby reducing the risk of positive and negative short circuits and ensuring the insulation between the positive electrode 210 and the negative electrode 220;On the other hand, it can be ensured that the dimension of the separator 230 extending beyond the end on the same side of the negative electrode 220 is not too large and the dimension of the first band 300 is not too large, thereby reducing the possibility of positional deviation when the band is fixed, reducing the risk of the first band 300 pulling the separator 230, and reducing the impact on the heat dissipation of the electrode assembly 200, thereby improving the reliability of the battery.

[0044] Optionally, “h * D1” 15 mm 2 , 150 mm 2 , 300 mm 2 , 450 mm 2 , 600 mm 2 , 750 mm 2 , 900 mm 2 , 1050 mm 2 , 1200 mm 2 , 1350 mm 2 , 1500 mm 2 , 1650 mm 2 , 1800 mm 2 be.

[0045] As an example, “h * D1” is preferably 100 mm 2 ≤ h * D1 ≤ 600 mm2 , where in this case “h * D1” 100 mm 2 , 120 mm 2 , 150 mm 2 , 200 mm 2 , 250 mm 2 , 300 mm 2 , 350 mm 2 , 400 mm 2 , 450 mm 2 , 500 mm 2 , 560 mm 2 , 570 mm 2 , 580 mm 2 , 590 mm 2 , 600 mm 2 By further controlling "h * D1" to conform to the above preferred range, the risk of folding the separator and short-circuiting the positive and negative electrodes can be further reduced. Moreover, the probability of positional deviation when the tape is fixed can be further reduced, and the risk of the tape pulling the separator can be reduced.

[0046] According to other embodiments, “h” satisfies the following: 0.5 mm ≤ h ≤ 3 mm.

[0047] According to the above embodiment, by further controlling the dimension of one end of the separator 230 beyond the end on the same side of the negative electrode 220 to conform to the above range, on the one hand, it can reduce the possibility of pulling the separator 230 to cause the separator 230 to be folded and buckled when the tape is fixed, thereby reducing the risk of a short circuit between the positive and negative electrodes; on the other hand, it can avoid an excessively large dimension of the separator 230 extending beyond the negative electrode 220, thereby reducing the impact on heat dissipation of the cell.

[0048] Optionally, “h” can be 0.5mm, 0.7mm, 0.9mm, 1.1mm, 1.3mm, 1.5mm, 1.7mm, 1.9mm, 2.1mm, 2.3mm, 2.5mm, 2.7mm, 3mm.

[0049] “D1” satisfies the following: 20 mm ≤ D1 ≤ 650 mm.

[0050] According to the above embodiment, by controlling the sum of the dimensions of the plurality of first bands 300 to conform to the above range, on the one hand, the bonding force of the plurality of first bands 300 to the battery cell can be improved and the probability of swelling of the battery cell can be reduced; on the other hand, the influence of the first band 300 on the heat dissipation of the electrode assembly 200 can be reduced and the probability of poor heat dissipation of the electrode assembly 200 can be reduced, and the manufacturing cost of the cell can also be reduced.

[0051] Optionally, “D1” can be 20mm, 30mm, 40mm, 60mm, 90mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm, 500mm, 530mm, 580mm, 610mm, 630mm, 650mm.

[0052] As an example, “D1” is preferably 60 mm ≤ D1 ≤ 300 mm, in which case “D1” can be 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 150 mm, 200 mm, 250 mm, 260 mm, 270 mm, 280 mm, 290 mm, 300 mm.

[0053] “h” is preferably 1 mm ≤ h ≤ 2.5 mm, in which case “h” can be 1 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm, 2.1 mm, 2.3 mm, 2.5 mm.

[0054] As an example, the test results in Table 1 below show the test results of the battery short circuit rate and cell temperature of several specific examples and comparative examples. Table 1. Test results h D1 h*D1 Battery short circuit rate Cell temperature test result Example 1 2 150 300 Not short-circuited Good Example 2 1 100 100 Not short-circuited Good Example 3 2,5 240 600 Not Good short-circuited Example 4 1,2 300 360 Not short-circuited Good Example 5 2,4 60 144 Not short-circuited Good Example 6 3 40 120 Not short-circuited Good Example 7 0,5 250 125 2% Good Example 8 1,2 560 672 Not short-circuited Qualified Example 9 0,7 22 15,4 5% Good Example 10 2,9 590 1711 Not short-circuited Qualified Comparison example 1 0,6 21 12,6 75 % Not qualified Comparison example 2 3 650 1950 20 % Not qualified

[0055] In Table 1, the battery short-circuit rate is the ratio of the number of short-circuited batteries in 100 batteries to the total number of batteries, 100, and the formula is (short-circuited batteries / 100)*100%. The battery short-circuit test method includes using a pulse short-circuit tester to connect the positive and negative tabs of the bare cell and test the voltage between the positive and negative tabs. If the pulse voltage rise "Vp" is less than 200V, it is determined that the battery is short-circuited; if the pulse voltage rise "Vp" reaches 200V or more, it is determined that the battery is not short-circuited.

[0056] In Table 1, the cell temperature test procedure includes installing the cell in the case body, sealing and welding the cover plate and case body, and providing a terminal on the cover plate to test the battery's temperature rise. The specific test steps are as follows: 1) For lithium iron phosphate batteries: charge at a constant current from 4C to 3.65V and charge at a constant voltage until the current drops to 0.05C; for ternary batteries: charge at a constant current from 4C to 4.25V and charge at a constant voltage until the current drops to 0.05C; a temperature sensor is connected to the terminal post, and during the charging process, the terminal post temperature is sensed to obtain the highest temperature "T" of the terminal post area. If the highest temperature "T" of the terminal post area is ≤ 45°C, it is good; if 45°C < T ≤ 65°C, it is qualified; and if T > 65°C, it is not qualified.

[0057] From the above test results, it can be seen that the parameters of Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Example 7, Example 8, Example 9 and Example 10 are all within the protection range of “h”, “D1” and “h * D1” of the above-mentioned present application, the temperature test results are all good and the short circuit rate is less than 20%.

[0058] In the test, the parameter "h" in Examples 1 to 5 is within the preferred range of "h" of the present application, the parameter "D1" in Examples 1 to 5 is within the preferred range of "D1" of the present application, and the parameter "h * D1" in Examples 1 to 5 is within the preferred range of "h * D1" of the present application. The temperature test results of Examples 1 to 5 are all good, and no short circuit occurs.

[0059] The parameters "h" and "D1" in Example 6 and Example 7 are outside the preferred protection range of the corresponding parameters, while the parameter "h * D1" is within the corresponding range of the above-mentioned preferred embodiments. The temperature test results of Example 6 are all good, with no short circuit occurring. The temperature test result of Example 7 is good, but the battery short circuit rate is 2%.

[0060] The parameters "h" and "D1" according to Example 8 are within the preferred protection range of the corresponding parameters, while the parameter "h * D1" is not within the preferred protection range of the corresponding parameters. According to Example 8, no short circuit occurs, and the temperature test result is only qualified.

[0061] All parameters according to Examples 9 and 10 are not within the preferred range of the corresponding parameters. The temperature test result of Example 9 is good, but the battery short-circuit rate is 5%. According to Example 10, no short circuit occurs, but the temperature test result is only qualified.

[0062] The parameter "h * D1" according to Comparative Example 1 is not within the preferred range of the corresponding parameters and is smaller than the lower limit of the protective range of the corresponding parameters. In this case, the probability of pulling the separator 230 increases when the tape is fixed, causing the separator 230 to fold and buckle, thereby increasing the risk of a short circuit between the positive and negative electrodes, resulting in a battery short circuit rate of up to 75%, a large increase in battery temperature, and an unqualified temperature test result.

[0063] The parameter "h*D1" according to Comparative Example 2 is not within the preferred range of the corresponding parameter, which is higher than the upper limit of the protection range of the corresponding parameter. In this case, the separator 230 is easily torn when the tape is fixed, increasing the risk of a short circuit between the positive and negative electrodes, causing the short circuit rate of the battery to reach 20%. Furthermore, because the separator 230 is too large to extend beyond the negative electrode 220, it impairs the heat dissipation of the cell, reducing the heat dissipation rate of the battery and causing a large temperature rise in the battery, resulting in an insufficient temperature test result.

[0064] It can be seen that the parameter range of the present application reduces the battery short circuit rate and the maximum temperature of the terminal area of ​​the battery, thereby improving the reliability of the battery.

[0065] According to other embodiments, see the Fig. 4, Fig. 5 and Fig. 6, the electrode assembly 200 has a third side surface 203 and a fourth side surface 204, wherein the third side surface 203 and the fourth side surface 204 are provided opposite each other along the thickness direction “Z” of the electrode assembly 200.

[0066] The first tape 300 includes a first portion 301, a second portion 302, and a third portion 303 sequentially bonded to each other, the first portion 301 being bonded to the third side surface 203, the second portion 302 being bonded to the first side surface 201, and the third portion 303 being bonded to the fourth side surface 204, where “h” satisfies the following: 0.5 mm ≤ h ≤ 2.5 mm, and “D1” satisfies the following: 30 mm ≤ D1 ≤ 600 mm.

[0067] According to the above embodiment, the first portion 301, the second portion 302, and the third portion 303 of the first band 300 may be integrally formed as a whole or may be sequentially attached to each other to form a whole, and the present application does not impose any limitations in this regard.

[0068] The first portion 301 of the first tape 300 is bonded to the third side surface 203, the third portion 303 is bonded to the fourth side surface 204, and the second portion 302 is bonded to the first side surface 201. It can be seen that the first tape 300 forms a U-shaped structure bonded to the side of the electrode assembly 200. It can be seen that the separator 230, when the tape is fixed, has a soft texture and is easily influenced by the force of bonding the tape to generate wrinkles and creases. Therefore, by controlling "h" and "D1" to conform to the above range, on the one hand, the probability of wrinkles and creases of the separator 230 when the tape is fixed is further reduced.On the other hand, the sum of the dimensions of a plurality of first bands 300 can be appropriately reduced as needed, thereby further reducing the impact on the heat dissipation of the electrode assembly 200 and further reducing the likelihood of poor heat dissipation of the battery cell.

[0069] Optionally, “h” can be 0.5mm, 0.7mm, 0.9mm, 1.1mm, 1.3mm, 1.5mm, 1.7mm, 1.9mm, 2.1mm, 2.3mm, 2.5mm.

[0070] Optionally, “D1” can be 30mm, 40mm, 60mm, 90mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm, 500mm, 530mm, 580mm, 600mm.

[0071] According to other embodiments, see Fig. 4, along the width direction “Y” of the electrode assembly 200, the dimension of the first portion 301 is “L1”, while the dimension of the third portion 303 is “L2”, satisfying: 5 mm ≤ L1 ≤ 40 mm, 5 mm ≤ L2 ≤ 40 mm.

[0072] According to the above embodiment, by controlling "L1" and "L2" within the above range, on the one hand, the connection strength between the first tape 300 and the electrode assembly 200 can be improved, thereby improving the bonding effect of the first tape 300 to the separator 230, reducing the likelihood of battery cell loosening, reducing local lithium-ion transfer impedance, and improving the overall battery performance; on the other hand, it is advantageous to reduce the likelihood of tape fixing position offset during bonding and fixing, thereby reducing the risk of the first tape 300 tearing the separator 230, and moreover, it can reduce the impact on heat dissipation of the electrode assembly 200 and further reduce the likelihood of poor heat dissipation of the cell.

[0073] Optionally, “L1” can be 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm.

[0074] Optionally, “L2” can be 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm.

[0075] According to other embodiments, see Fig. 7, a plurality of first bands 300 are provided at intervals along the longitudinal direction “X” of the electrode assembly 200.

[0076] According to the above embodiment, because a plurality of first tapes 300 are provided at intervals along the longitudinal direction "X" of the electrode assembly 200, the first tape 300 can be firmly attached to the surface of the electrode assembly 200 and play a role in fixing the electrode assembly 200. This reduces the difficulty of bonding and reduces the likelihood of the first tape 300 displacing and tearing the separator 230. On the other hand, it reduces the likelihood of local looseness of the battery cell and reduces the local lithium-ion transfer impedance of the cell, which is conducive to improving the overall performance of the battery.

[0077] According to other embodiments, see Fig. 7, along the longitudinal direction “X” of the electrode assembly 200, the distance between two adjacent first bands 300 is “L3”, which satisfies the following: 20 mm ≤ L3 ≤ 70 mm.

[0078] According to the above embodiment, because the distance between two adjacent first bands 300 conforms to the above range, on the one hand, the distance between adjacent first bands 300 is prevented from being too large, the bonding effect on the cell is improved, and the possibility of the electrode assembly 200 being too loose between adjacent first bands 300 is reduced, thereby reducing the transfer impedance of lithium ions between the positive and negative electrodes. On the other hand, the distance between adjacent first bands 300 is prevented from being too small, reducing the possibility of the separator 230 being pulled between adjacent first bands 300 when it is fixed by the bands on both sides, thereby reducing the possibility of the separator 230 being buckled between adjacent first bands 300.

[0079] Optionally, “L3” can be 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm.

[0080] As an example, when two adjacent first bands 300 are not provided in parallel or the dimensions of two adjacent first bands 300 along the longitudinal direction “X” of the electrode assembly 200 are different, the minimum distance between the two along the longitudinal direction “X” of the electrode assembly 200 corresponds to the above range, whereby the distance between adjacent first bands 300 can be avoided from being too small, the possibility of the separator 230 being pulled between adjacent first bands 300 when being fixed by the bands on both sides can be reduced, and consequently the possibility of the separator 230 being kinked between adjacent first bands 300 can be reduced.

[0081] According to other embodiments, see Fig.7, along the longitudinal direction “X” of the electrode assembly 200, the dimension of the first band 300 is “d”, which satisfies 8 mm ≤ d ≤ 100 mm.

[0082] According to the above embodiment, because the dimension of the first band 300 along the longitudinal direction “X” of the electrode assembly 200 corresponds to the above range, on the one hand, the first band 300 is prevented from being too small, the force-bearing area of ​​the separator 230 is increased, and the pressure on the separator 230 is reduced, thereby reducing the risk of folding and buckling of the separator 230 and reducing the risk of short-circuiting of the exposed positive and negative electrodes of the electrode;On the other hand, it prevents the first tape 300 from being too large, reducing the probability that the tape fixing position is offset during bonding and fixing, thereby reducing the risk that the first tape 300 tears the separator 230, and moreover, it can reduce the influence of the first tape 300 on the heat dissipation of the electrode assembly 200 and reduce the probability of poor heat dissipation of the electrode assembly 200.

[0083] Optionally, “d” can be 8mm, 18mm, 28mm, 38mm, 48mm, 58mm, 68mm, 78mm, 88mm, 98mm, 100mm.

[0084] As an example, at least two first bands 300 have different dimensions along the longitudinal direction “X” of the electrode assembly 200.

[0085] It is understood that the dimensions of the plurality of first bands 300 along the longitudinal direction X of the electrode assembly 200 may be the same or different to facilitate improving the fixing effect at different positions as needed. For example, the width of the first band 300 at both ends along the longitudinal direction "X" of the electrode assembly 200 may be the same and different from the width of the first band 300 in other areas to further reduce the likelihood of folding of the separator 230 and ensure the heat dissipation effect of the electrode assembly 200.

[0086] According to other embodiments, see Fig. 7, along the width direction "Y" of the electrode assembly 200, the dimension of the negative electrode 220 exceeds the dimension of the positive electrode 210 by less than or equal to 2 mm; "d" satisfies 10 mm ≤ d ≤ 100 mm.

[0087] According to the above embodiment, by controlling the dimension of the negative electrode 220 to exceed the dimension of the positive electrode 210 along the width direction “Y” of the electrode assembly 200 by less than or equal to 2 mm, it is ensured that the edge of the separator 230 has sufficient pressure from the positive electrode 210, thereby further reducing the possibility of the separator 230 being buckled and reducing the risk of the positive electrode 210 and the negative electrode 220 being short-circuited after the separator 230 is buckled.

[0088] In addition, the risk of short circuit between the positive electrode and the negative electrode after folding the separator can be reduced due to the smaller dimension of the negative electrode than that of the positive electrode, and the probability of lithium deposition on the surface of the negative electrode can be avoided due to the smaller dimension of the negative electrode than that of the positive electrode; on the other hand, the probability of battery energy density being reduced due to the excessive lithium insertion position of the negative electrode can be reduced, thereby improving the safety and stability of the battery.

[0089] The value of the dimension of the negative electrode 220 that exceeds the dimension of the positive electrode 210 is greater than or equal to 0.5 mm.

[0090] By controlling "d" to conform to the above range, the force-bearing area of ​​the separator 230 is further increased and the pressure on the separator 230 is reduced, thereby reducing the risk of folding and buckling of the separator 230 and reducing the risk of short circuit between the positive electrode and the negative electrode of the exposed electrode; On the other hand, the first tape 300 is prevented from being too large, reducing the possibility of the tape fixing position being displaced during bonding and fixing, thereby reducing the risk of the first tape 300 tearing the separator 230.

[0091] Optionally, “d” can be 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm.

[0092] According to other embodiments, see the Fig. 6 and Fig.7, the battery cell further includes a plurality of second tapes 400, wherein the second tapes 400 are glued to the second side surface 202.

[0093] It can be seen that the second band 400 can be firmly attached to the side of the electrode assembly 200, can play a role in fixing the electrode assembly 200, can reduce the occurrence of multiple loose electrodes, and can reduce the likelihood of increased resistance caused by the direct contact between the positive electrode 210 and the negative electrode 220.

[0094] Along the longitudinal direction “X” of the electrode assembly 200, the sum of the dimensions of the plurality of second bands 400 is “D2”, which satisfies the following: 15 mm 2 ≤ h * D2 ≤ 1800 mm 2 .

[0095] According to the above embodiment, because the ratio of the sum of the dimensions of the plurality of second bands 400 to the dimension of an end of the separator 230 extending beyond the end on the same side of the negative electrode 220 corresponds to the above range, on the one hand, when the band is fixed, the pressing area of ​​the separator 230 can be increased, and the pressure on the separator 230 can be reduced, thereby reducing the likelihood of wrinkles and creases at the edge of the separator 230 and reducing the risk of a short circuit between the positive electrode and the negative electrode;On the other hand, it can be ensured that the dimension of the separator 230 extending beyond the end on the same side of the negative electrode 220 is not too large and the dimension of the second band 400 is not too large, thereby reducing the probability of positional deviation when the band is fixed, reducing the risk of the second band 400 pulling the separator 230, and reducing the influence on the heat dissipation of the electrode assembly 200, thereby reducing the probability of poor heat dissipation of the electrode assembly 200.

[0096] Optionally, “h * D2” can be 15mm 2 , 150 mm 2 , 300 mm 2 , 450 mm 2 , 600 mm 2 , 750 mm 2 , 900 mm 2 , 1050 mm 2 , 1200 mm 2 , 1350 mm 2 , 1500 mm 2 , 1650 mm 2 , 1800 mm 2 be.

[0097] According to some other embodiments, the length of the electrode assembly 200 is greater than or equal to 300 mm, where “D1” satisfies 35 mm ≤ D1 ≤ 600 mm.

[0098] According to the above embodiment, by controlling the length of the electrode assembly 200 to be greater than or equal to 300 mm, the length of the electrode assembly 200 is increased, which helps improve the battery energy density. Moreover, it is easy to design the motor assembly more freely. Therefore, "D1" is further controlled to conform to the above range, increasing the dimension of the tape along the longitudinal direction "X" of the electrode assembly 200, thereby improving the bonding effect of the tape to the multilayer electrode. Specifically, the length of the electrode assembly 200 can be greater than or equal to 300 mm and less than or equal to 1000 mm; specifically, it can be 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 900 mm, 1000 mm.

[0099] By controlling "D1" to the above range, the bonding force of the electrode assembly 200 is further improved, which is beneficial for the transfer of lithium ions during the subsequent charging and discharging process. On the other hand, it ensures that the dimension of the first band 300 is not too large, thereby reducing the likelihood of positional deviation when the band is fixed, reducing the risk of the first band 300 pulling the separator 230, and reducing the risk of the pole piece falling off or the risk of a short circuit between the positive electrode and the negative electrode.

[0100] Optionally, “D1” can be 35 mm, 45 mm, 65 mm, 95 mm, 155 mm, 205 mm, 255 mm, 305 mm, 355 mm, 405 mm, 455 mm, 505 mm, 535 mm, 585 mm or 605 mm.

[0101] According to other embodiments, the thickness of the separator 230 is greater than or equal to 8 µm and less than or equal to 40 µm.

[0102] According to the above embodiment, by controlling the thickness of the separator 230 to conform to the above range, on the one hand, it is prevented from being too thin, so that it is difficult to fix and easy to buckle, thereby reducing the probability of buckling of the separator 230; on the other hand, it is prevented from being too thick to cause excessive internal resistance, which is conducive to reducing the energy loss of the battery during the charging and discharging process, improving the charging and discharging efficiency of the battery, allowing the battery to complete the charging process faster, and being able to output a larger current during discharging, thereby improving the overall performance of the battery.

[0103] According to other embodiments, see Fig.8, the plurality of separators 230 includes a first separator 720 and a second separator 730, wherein the first separator 720 and the second separator 730 are provided along the thickness direction of the electrode assembly on both sides of the negative electrode 220 to form a negative electrode unit 700, wherein the first separator 720 and the second separator 730 are both adhered and sealed to at least a part of the negative electrode 220.

[0104] A plurality of the negative electrode units 700 and the plurality of positive electrodes 210 may be stacked in sequence.

[0105] According to the above embodiment, the negative electrode 220, the first separator 720, and the second separator 730 are assembled into a negative electrode unit 700 to realize a modular design. In this case, the first separator 720 and the second separator 730 are bonded and sealed to at least a portion of the negative electrode 220 to form a sealing structure and increase the hardness of the separator 230 at the edge seal, thereby reducing the risk of the separator 230 being buckled. This contributes to setting the dimension of the first tape 300 smaller along the longitudinal direction "X" of the electrode assembly 200, thereby reducing the likelihood of the tape pulling the separator 230 and further reducing the risk of the separator 230 being folded and buckled.

[0106] According to other embodiments, see the Fig. 2 and Fig.9, the battery cell further includes a second tab 600, wherein the first tab 500 and the second tab 600 have opposite polarities, and the first tab 500 and the second tab 600 are each provided at both ends of the electrode assembly 200 in the longitudinal direction “X”.

[0107] It is understood that when multiple battery cells need to be connected in series or parallel, the arrangement of the tabs at both ends makes connecting the busbar easier and more convenient. Furthermore, the positive tab and the negative tab located along the longitudinal direction "X" at both ends of the electrode assembly 200 can also prevent heat from concentrating on one side of the electrode assembly 200, thereby ensuring the heat dissipation effect of the electrode assembly 200 and reducing the likelihood of heat concentration.

[0108] According to other embodiments, see Fig. 9, the housing 100 includes a housing body 120 and an end cap 110, wherein the housing body 120 and the end cap 110 are enclosed to form a receiving cavity 101. A plurality of end caps 110 may be provided, wherein the plurality of end caps 110 includes a first end cap 111 and a second end cap 112. The first end cap 111 and the second end cap 112 are located at both ends of the housing body 120 along the longitudinal direction "X," respectively. The first end cap 111 and the second end cap 112 are each provided with a first terminal assembly 111a and a second terminal assembly 112a, wherein the first terminal assembly 111a and the second terminal assembly 112a are electrically connected to the first tab 500 and the second tab 600, respectively.

[0109] It can be seen that the terminal assembly is used to electrically connect the battery and the external circuit. The terminal assembly can be connected, for example, to the busbar, etc., to realize a series and parallel connection between multiple battery cells, and the present application imposes no restrictions in this regard.

[0110] According to the above embodiment, the terminal assembly is electrically connected to the tab, which can provide a stable conduction path for current within the battery. The first terminal assembly 111a is connected to the first tab 500, while the second terminal assembly 112a is connected to the second tab 600, so that during the battery charging and discharging process, current can be transferred in an orderly manner from the electrode via the tab to the terminal and then to the external circuit, ensuring that the battery can stably output or input current and ensure normal battery operation.

[0111] It can be appreciated that the tab may be connected directly to the terminal assembly; the tab and terminal assembly may also be connected via an intermediate piece, such as an adapter. Specifically, the tab may be connected to the adapter first, with the adapter then being electrically connected to the terminal assembly. The present application imposes no limitations in this regard.

[0112] Additionally, the first terminal assembly 111a and the second terminal assembly 112a are each connected to the corresponding tabs, which can fix and support the tabs to a certain extent, making the position of the tabs within the battery more stable. In this case, the end cap 110 and the case body 120 are enclosed to form a receiving cavity 101. The connection between the terminal assembly and the tab also helps improve the stability of the entire structure of the case 100, so that the internal structure of the battery is not easily displaced or damaged when subjected to external forces or vibration.

[0113] According to other embodiments, the present application provides a battery device including a battery cell as described in any of the above embodiments.

[0114] Because the battery device of the embodiment of the present application includes the battery cell as described in any one of the above embodiments, the performance and safety of the battery device are improved, and the reliability is better.

[0115] According to other embodiments, the embodiment of the present application provides an electrical device including the battery device as described in the above embodiments.

[0116] Because the electric device of the embodiment of the present application has the battery device as described in the above embodiments, the reliability of the electric device is improved.

[0117] The battery device disclosed in the embodiment of the present application can be used in electrical devices such as, but is not limited to, vehicles, ships, or aircraft. A power supply system including the battery cell, battery device, etc. disclosed in the present application can be used.

[0118] The embodiment of the present application provides an electrical device in which a battery cell is provided as a power source, wherein the electrical device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, a power tool, an electric bicycle, an electric motorcycle, an electric car, a ship, a spacecraft, etc. The electric toy may include a stationary or mobile electric toy, e.g., a game console, an electric car toy, an electric ship toy, or an electric airplane toy, etc., wherein the spacecraft may include an airplane, a rocket, a space shuttle, or a spacecraft, etc.

[0119] For convenience of explanation, the following embodiments will be described by taking a vehicle as an example of an electric device according to an embodiment of the present application.

[0120] The vehicle includes a fuel vehicle, a gas vehicle, or a new energy vehicle, where the new energy vehicle includes, but is not limited to, a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. A battery is provided at the bottom, front, or rear of the vehicle. The battery supplies power to the vehicle. The battery serves as the operating power source of the vehicle 1000 and supplies power to the vehicle's circuitry, including meeting the vehicle's operating power requirements during startup, navigation, and operation.

[0121] The vehicle also includes a control unit and a motor, with the control unit being used to control the battery to supply power to the motor, including meeting the vehicle's operating power requirements during startup, navigation, and driving.

[0122] According to some embodiments of the present application, the battery may be provided not only as the operating power source of the vehicle, but also as the motive power source of the vehicle, replacing or partially replacing fuel or natural gas to provide motive power for the vehicle.

[0123] The battery includes an outer casing and a battery cell contained therein. The outer casing can take on various structures. According to some embodiments, the outer casing includes a first sub-casing and a second sub-casing, wherein the first sub-casing and the second sub-casing are combined to form an outer casing, wherein the first sub-casing and the second sub-casing together define a receiving space for receiving the battery cell. The second sub-casing includes a square structural element with an opening on one side, while the first sub-casing includes a square structural element with an opening on one side. The openings of the first sub-casing and the second sub-casing are combined accordingly, such that the first sub-casing and the second sub-casing together define a receiving space.The first sub-housing contains a plate-shaped structural element, while the first sub-housing covers the opening side of the second sub-housing.

[0124] In the battery, the battery cell can be provided in multiples, wherein the plurality of battery cells can be connected in series, parallel, or in a mixed connection. Mixed connection means that a plurality of battery cells are connected both in series and in parallel. A plurality of battery cells can be connected directly in series, parallel, or in a mixed connection, in which case the whole formed by the plurality of battery cells is housed in the outer casing; of course, the battery can also be a battery module formed by connecting a plurality of battery cells in series, parallel, or in a mixed connection, in which case the plurality of battery modules are connected in series, parallel, or in a mixed connection to form a whole and housed in the outer casing. The battery can also include other structures. The battery can, for example,further include a converging component for implementing an electrical connection between the plurality of battery cells.

[0125] According to the above embodiment, the battery cell includes at least one of a secondary battery and a primary battery; the battery cell includes, but is not limited to, a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery.

[0126] It should also be noted that the terms "include," "comprise," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, commodity, or device that includes a set of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent in such a process, method, commodity, or device. In the absence of further limitations, the elements defined by the phrase "includes a..." do not exclude the presence of other identical elements in the process, method, commodity, or device that include the elements.

[0127] Each embodiment in this application text is described in a progressive manner, where the same and similar parts may be referred to between the embodiments, with the embodiments focusing on the differences from other embodiments. In particular, for a system embodiment, the description is relatively simple because it is substantially similar to the corresponding method embodiment, where the relevant parts may be referred to the partial description of the method embodiment.

[0128] The above description is only one embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modification, equivalent substitution, improvement, etc., made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

[0129] Although the embodiments of the present application have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, all such modifications and variations being within the scope of the appended claims.

Claims

[1] Battery cell, characterized by that it includes: a housing with a receiving cavity; an electrode assembly provided in the receiving cavity, the electrode assembly being constructed as a stacked cell, the stacked cell comprising a plurality of positive electrodes, a plurality of negative electrodes, and a separator, the plurality of positive electrodes and the plurality of negative electrodes being stacked in sequence along a thickness direction of the electrode assembly, the separator being provided between each adjacent positive electrode and negative electrode and on the outside of the outermost positive electrode and / or negative electrode along the thickness direction of the electrode assembly; the thickness direction being parallel to the direction in which the positive electrodes and the negative electrodes are stacked; a first tab provided at one end of the electrode assembly in a longitudinal direction; wherein the electrode assembly has a first side surface and a second side surface opposite each other in a width direction, and the longitudinal direction, the thickness direction, and the width direction of the electrode assembly are perpendicular to each other, wherein the battery cell further comprises a first tape, wherein at least one first tape is provided, and the first tape is adhered to the first side surface, the total length of the first tape along the longitudinal direction of the electrode assembly is “D1”, the dimension of an end of the separator that extends beyond the end of the same side of the negative electrode along the width direction of the electrode assembly is “h”, wherein the following is satisfied: 15 mm 2 ≤ h * D1 ≤ 1800 mm 2 . [2] Battery cell according to claim 1, characterized bythat ‘h’ satisfies the following: 0,5 mm ≤ h ≤ 3 mm, and ‘D1’ satisfies the following: 20 mm ≤ D1 ≤ 650 mm. [3] Battery cell according to one of the preceding claims, characterized by that “h * D1” satisfies the following: 100 mm 2 ≤ h * D1 ≤ 600 mm 2 . [4] Battery cell according to one of the preceding claims, characterized byin that the electrode assembly has a third side surface and a fourth side surface, and the third side surface is provided opposite to the fourth side surface along the thickness direction of the electrode assembly; the first tape comprises a first portion, a second portion, and a third portion sequentially bonded to each other, the first portion being bonded to the third side surface, the second portion being bonded to the first side surface, and the third portion being bonded to the fourth side surface, and the "h" satisfies the following: 0.5 mm ≤ h ≤ 2.5 mm, and "D1" satisfies the following: 30 mm ≤ D1 ≤ 600 mm. [5] Battery cell according to claim 4, characterized by that along the width direction of the electrode assembly, the dimension of the first portion is “L1” and the dimension of the third portion is “L2”, wherein the following are satisfied: 5 mm ≤ L1 ≤ 40 mm, 5 mm ≤ L2 ≤ 40 mm. [6] Battery cell according to one of the preceding claims, characterized by that a plurality of the first bands are provided at intervals along the longitudinal direction of the electrode array. [7] Battery cell according to claim 6, characterized by that along the longitudinal direction of the electrode array, the distance between two adjacent first bands in the plurality of first bands is "L3", wherein the following is satisfied: 20 mm ≤ L3 ≤ 70 mm. [8] A battery cell according to any one of the preceding claims, wherein the material of the first tape is a polyimide film (PI film), an acrylimide film (PPA film) or a polyethylene film. [9] Battery cell according to one of the preceding claims, characterized by that the dimension of the first band is “d”, where the following is satisfied: 8 mm ≤ d ≤ 100 mm. [10] Battery cell according to claim 9, characterized bythat along the width direction of the electrode assembly, the value by which the dimension of the negative electrode exceeds the dimension of the positive electrode is less than or equal to 2 mm; where "d" satisfies 10 mm ≤ d ≤ 100 mm. [11] Battery cell according to one of the preceding claims, characterized by that the battery cell further comprises a plurality of second tapes bonded to the second side surface; wherein along the longitudinal direction of the electrode assembly, the sum of the dimensions of the plurality of second tapes is "D2", wherein the following is satisfied: 15 mm 2 ≤ h * D2 ≤ 1800 mm 2 . [12] Battery cell according to one of the preceding claims, characterized by that the length of the electrode assembly is greater than or equal to 300 mm and ‘D1’ satisfies 35 mm ≤ D1 ≤ 600 mm. [13] Battery cell according to one of the preceding claims, characterized bythat the thickness of the separator is greater than or equal to 8 µm and less than or equal to 40 µm. [14] Battery cell according to one of the preceding claims, characterized by that the plurality of separators comprise a first separator and a second separator, and along the thickness direction of the electrode assembly, the first separator and the second separator are provided on both sides of the negative electrode to form a negative electrode unit, and the first separator and the second separator are both adhered and sealed to at least a part of the negative electrode; wherein a plurality of the negative electrode units and the plurality of positive electrodes are stacked in sequence. [15] Battery cell according to one of the preceding claims, characterized bythat the battery cell further comprises a second tab, wherein the first tab and the second tab have opposite polarities and the first tab and the second tab are provided at both ends of the electrode assembly in the longitudinal direction, respectively. [16] Battery cell according to claim 15, characterized byin that the housing comprises a housing body and an end cap, the housing body and the end cap are enclosed to form the receiving cavity, a plurality of end caps are provided and the plurality of end caps comprise a first end cap and a second end cap, the first end cap and the second end cap are located at both ends of the housing body along the longitudinal direction, the first end cap and the second end cap are provided with a first terminal arrangement and a second terminal arrangement, respectively, and the first terminal arrangement and the second terminal arrangement are electrically connected to the first tab and the second tab, respectively. [17] Battery device, characterized by that it comprises a battery cell according to one of claims 1 to 16 [18] Electrical device, characterized bythat it comprises a battery cell according to one of claims 1 to 16 or a battery device according to claim 17 or comprises a battery with a battery cell according to one of claims 1 to 16. [19] Electrical device according to claim 18, which is designed as a vehicle, ship, aircraft or power supply system, or which is designed as a vehicle, wherein the battery is provided as the operating power source of the vehicle and / or as the motive power source of the vehicle, wherein it replaces or partially replaces fuel or natural gas to provide motive power for the vehicle. [20] An electrical device according to claim 18, wherein the electrical device is a mobile phone, a tablet computer, a laptop computer, an electric toy, a power tool, an electric bicycle, an electric motorcycle, an electric car or electric vehicle, a ship or a spacecraft, preferably wherein the electric toy includes a stationary or mobile electric toy, e.g., a game console, an electric car toy, an electric ship toy, or an electric airplane toy, preferably wherein the spacecraft includes an airplane, a rocket, a space shuttle, or a spacecraft.

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