Battery cell shell and battery cell

Abstract

The application discloses an electric core shell and an electric core. The electric core shell comprises a plurality of outer sides, a transition curved surface connecting two adjacent outer sides, and a flow guide structure arranged on at least part of the transition curved surface and used for guiding fluid to be uniformly distributed on the transition curved surface. The flow guide structure is used for guiding the fluid to be uniformly distributed, thereby improving the problem of insufficient coating edge thickness or overflow of the light-curing jet printing technology at the edge of the electric core, and improving the uniformity of the coating.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a cell housing and a cell. Background Technology

[0002] In the battery industry, photopolymer inkjet printing technology is used as a coating process to prepare insulating coatings for battery cell casings.

[0003] In related technologies, the battery cell casing usually has a regular polyhedral shape, with significant abrupt changes in size and sharp geometric edges, which makes it easy for the photocurable coating to have uneven thickness or overflow at the edges, affecting insulation and reliability. Utility Model Content

[0004] This application provides a battery cell housing and a battery cell to at least partially solve the above-mentioned technical problems.

[0005] In a first aspect, embodiments of this application provide a battery cell housing, including: a plurality of outer surfaces; a transition surface connecting two adjacent outer surfaces; and a flow guiding structure disposed on at least a portion of the transition surface for guiding fluid to be uniformly distributed on the transition surface. By guiding the fluid to be uniformly distributed through the flow guiding structure, the problem of insufficient coating edge thickness or overflow at the edges of the battery cell in photopolymer inkjet printing technology is improved, thereby enhancing coating uniformity.

[0006] Optionally, the flow guiding structure includes at least one flow guiding unit, which is arranged along the extension direction of the transition surface. The flow guiding unit's arrangement along the extension direction of the transition surface effectively guides the flow of the liquid coating, enhancing the uniform spreading effect of the coating.

[0007] Optionally, the flow guiding unit includes a flow guiding channel, which is arranged along the extension direction of the transition surface. The flow guiding channel provides a clear flow path for the liquid coating, and utilizes capillary action to ensure that the coating is evenly distributed within the flow guiding channel and on the transition surface.

[0008] Optionally, the flow channel and the transition surface are connected by a smooth transition. The smooth transition reduces the obstruction to the flow of the paint, allowing the paint to flow smoothly from the transition surface to the flow channel and spread evenly across the entire transition surface.

[0009] Optionally, the flow guiding structure includes multiple flow guiding units, which are arranged circumferentially along the transition surface. The multiple flow guiding units, arranged circumferentially along the transition surface, disperse and guide the flow of the coating, resulting in a more uniform coating thickness across the entire transition surface.

[0010] Optionally, along the first direction intersecting the extension direction of the transition surface, the distance L1 between adjacent edges of two adjacent flow guiding units satisfies: 0.03mm ≤ L1 ≤ 0.1mm. Reasonably controlling the distance between adjacent flow guiding units ensures the natural transition and filling of the coating within the interval area, while fully utilizing the guiding role of the flow guiding units and avoiding localized excessive thickness or thinness of the coating.

[0011] Optionally, the flow guiding structure is provided on a portion of the transition surface; in the portion of the transition surface where the flow guiding structure is not provided, a cross section is made along the direction perpendicular to the extension of the transition surface, and the outer contour of the transition surface includes a first circular arc segment and a second circular arc segment that are continuously connected to each other, and the tangents at the connection between the two form an included angle α.

[0012] By using a combination of the first and second circular arc segments, the processing difficulty is reduced, while maintaining a smooth transition of the transition surface, which helps the coating to be distributed evenly.

[0013] Optionally, at least one of the following conditions must be met: the included angle α satisfies 156°≤α≤180°; the radius of the first arc segment is Rb, and the radius of the second arc segment is Rc, satisfying Rb=Rc≥0.05mm+L2, where L2 is the wall thickness of the outermost side of the battery cell housing with the largest area; the projected dimensions of the transition surface in the orthogonal direction are h1 and h2, respectively, the radius of the first arc segment is Rb, and the radius of the second arc segment is Rc, satisfying h1=h2≥0.7Rb=0.7Rc; the range of the projected dimensions h1 and h2 of the transition surface 11 in its orthogonal direction satisfies: |h1-h2| ≤0.5 mm. Reasonable control of the included angle α and the arc radius ensures the smoothness of the transition surface and the smoothness of the coating flow; at the same time, by matching the projected dimensions with the arc radius, the transition surface presents a regular and symmetrical shape, which helps to achieve uniform coating distribution.

[0014] Optionally, at least one of the following conditions must be met: the outer surface of the battery cell casing has a microstructure, including at least one of pits, protrusions, and cracks, to increase the contact area between the coating and the outer surface; the outer surface of the battery cell casing has a plasma treatment layer to ensure that the surface energy of the battery cell casing is not less than 50 mN / m. The microstructure increases the contact area between the coating and the outer surface of the battery cell casing, improving adhesion; the plasma treatment layer improves the surface energy, allowing the coating to better wet and penetrate the surface of the battery cell casing, enhancing the bonding force between the coating and the substrate.

[0015] Optionally, the pits satisfy at least one of the following: pit diameter D, 20μm≤D≤1000μm; pit depth h3, 1μm≤h3≤30μm; and distance between adjacent pits L3, L3≤0. By rationally controlling the diameter, depth, and spacing of the pits, effective mechanical anchoring points are formed, significantly enhancing the adhesion between the coating and the outer surface of the battery cell casing, while also guiding the coating to distribute evenly.

[0016] Optionally, at least two photocurable insulating layers are sequentially formed on the outer surface of the cell casing, with the thickness h4 of each photocurable insulating layer satisfying 10μm≤h4≤150μm. This multi-layer photocurable insulating layer design, through pre-curing and final curing processes, effectively controls the coating's flowability and curing quality, ensuring the coating's smoothness and thickness uniformity, and improving its insulation performance.

[0017] Secondly, embodiments of this application provide a battery cell including a battery cell casing as described above. Using a battery cell casing with the aforementioned superior characteristics improves the overall performance and safety of the battery cell.

[0018] In the battery cell housing of this application embodiment, when liquid coating is sprayed onto the transition curved surface of the battery cell housing, the flow guiding structure spreads the liquid coating evenly on the transition curved surface. Due to the guiding effect of the flow guiding structure, the discontinuity of the liquid coating flow at the edge is reduced, so that the coating can be distributed on the transition curved surface in a predetermined manner, thereby improving the problem of insufficient coating edge thickness or overflow at the edge of the battery cell in the photocuring inkjet printing technology.

[0019] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0021] Figure 1 This is a three-dimensional schematic diagram of the battery cell casing provided in the embodiments of this application; Figure 2 yes Figure 1 A magnified view of a section at point A in the middle; Figure 3 This is a front view schematic diagram of the battery cell housing provided in an embodiment of this application; Figure 4 yes Figure 3 Enlarged schematic diagram of part B in the middle; Figure 5 This is a side cross-sectional schematic diagram of the battery cell housing provided in the embodiments of this application; Figure 6 yes Figure 5 An enlarged schematic diagram of section C; Explanation of reference numerals in the attached figures: 1. Battery cell casing; 10. Outer surface; 11. Transition surface; 111. First circular arc segment; 112. Second circular arc segment; 12. Flow guiding structure; 120. Flow guiding unit; 121. Flow guiding groove. Detailed Implementation The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0022] In the battery industry, photopolymer inkjet printing technology, as a coating process, has been widely used in the preparation of insulating coatings for battery cell casings.

[0023] In related technologies, the battery cell casing usually has a regular polyhedral shape, with significant abrupt changes in size and sharp geometric edges, which makes it easy for the photocurable coating to have uneven thickness or overflow at the edges, affecting insulation and reliability.

[0024] Regarding the above technical issues, firstly, refer to Figure 1 , Figure 3 This application provides a battery cell housing 1, including: a plurality of outer surfaces 10; a transition surface 11 connecting two adjacent outer surfaces 10; and a flow guiding structure 12 disposed on at least a portion of the transition surface 11 for guiding fluid to be uniformly distributed on the transition surface 11 through capillary action.

[0025] In this embodiment, when the liquid coating is sprayed onto the transition surface 11 of the cell housing 1, the flow guiding structure 12 uses capillary action to evenly spread the liquid coating on the transition surface 11. Due to the guiding effect of the flow guiding structure 12, the discontinuity of the liquid coating flow at the edges is reduced, allowing the coating to be distributed on the transition surface 11 in a predetermined manner. This improves the problem of insufficient coating edge thickness or overflow at the edges of the cell in photopolymer inkjet printing technology.

[0026] Furthermore, the liquid coating is evenly spread on the transition surface 11 by the flow guiding structure 12, which allows the coating to better bond with the battery cell housing 1, increases the contact area between the coating and the housing, improves the bonding force between the two, and thus reduces the risk of coating falling off.

[0027] For example, the guiding structure 12 can be a groove structure, a micro-protrusion array structure, or a porous structure, all of which can guide the liquid coating to be evenly distributed on the transition surface 11. Specifically, for example, a portion of the transition surface 11 can be designed as a porous structure with a large number of tiny, interconnected pores. When the liquid coating is sprayed onto it, the coating will penetrate into these pores, and through capillary action, the liquid coating will be evenly distributed inside and on the surface of the porous structure.

[0028] For example, the battery cell housing 1 is integrally stamped and has six common outer surfaces 10, wherein the transition surface 11 between the outer surface 10 at the bottom of the battery cell housing 1 and the adjacent outer surface 10 is provided with a flow guiding structure 12.

[0029] In some embodiments, reference Figure 1 , Figure 2 The flow guiding structure 12 includes at least one flow guiding unit 120, which is arranged along the extension direction of the transition surface 11.

[0030] In this embodiment, the flow guiding structure 12 includes at least one flow guiding unit 120, and the flow guiding unit 120 is arranged along the extension direction of the transition surface 11. When the liquid coating is sprayed onto the transition surface 11 of the cell housing 1, the flow guiding unit 120 can play a guiding role. Taking the trench structure as an example, the liquid coating flows along the extension direction of the transition surface 11 under the guidance of the trench. At the same time, by utilizing capillary action, the liquid coating can gradually and uniformly spread inside the trench and on the transition surface 11.

[0031] In some embodiments, reference Figure 2 The flow guiding unit 120 includes a flow guiding groove 121, which is arranged along the extension direction of the transition surface 11.

[0032] In this embodiment, after the liquid coating is sprayed onto the transition surface 11 of the cell housing 1, it comes into contact with the guide channel 121. The guide channel 121 is arranged along the extension direction of the transition surface 11, providing a flow path for the liquid coating. At the same time, the sidewall of the guide channel 121 constrains and guides the liquid coating, and through capillary action, the liquid coating is not only uniformly distributed inside the guide channel 121, but also gradually diffuses into the transition surface 11 area around the guide channel 121, ultimately achieving uniform spreading of the liquid coating across the entire transition surface 11.

[0033] In some embodiments, reference Figure 2 , Figure 4 The sidewall of the guide channel 121 and the transition surface 11 are smoothly connected.

[0034] In this embodiment, since the flow channel 121 and the transition surface 11 are smoothly connected, there are no obvious abrupt structural changes such as steps or sharp corners. On the one hand, based on the capillary action principle, the liquid coating will generate capillary action inside the flow channel 121, resulting in a uniform distribution of the coating within the flow channel 121. Simultaneously, because the transition connection is smooth, the liquid coating flows continuously and smoothly from the transition surface 11 to the flow channel 121, without being hindered by structural abrupt changes. This allows the liquid coating to gradually diffuse from inside the flow channel 121 to the surrounding transition surface 11 region, thereby achieving uniform spreading of the liquid coating across the entire transition surface 11. On the other hand, the smooth transition surface 11 and the surface of the flow channel 121 allow coating molecules to more fully contact the surface of the battery cell housing 1, forming a tighter intermolecular force, which is beneficial for a firm bond between the coating and the battery cell housing 1.

[0035] Optionally, in a cross-section perpendicular to the extension direction of the transition surface 11, the profile of the guide channel 121 is a concave, smooth curve, such as a parabola. The concave, smooth curve profile of the guide channel 121 further enhances the uniformity of the coating flow within the guide channel 121 and the tightness of its contact with the surface of the cell housing 1.

[0036] In some embodiments, reference Figure 2 , Figure 4 The flow guiding structure 12 includes multiple flow guiding units 120, which are arranged circumferentially along the transition surface 11.

[0037] In this embodiment, multiple flow guiding units 120 are arranged circumferentially along the transition surface 11, and each flow guiding unit 120 can guide the liquid coating to be evenly distributed in its responsible area. Through this dispersed guidance method, the coating thickness on the entire transition surface 11 is more uniform, thereby improving the phenomenon of local over-thickness or under-thinness of the coating caused by the irregular shape of the transition surface 11.

[0038] Furthermore, the spaced arrangement of multiple flow guiding units 120 further increases the contact area between the coating and the battery cell housing 1, which is conducive to the formation of a tighter and more uniform intermolecular force between the coating molecules and the surface molecules of the battery cell housing 1, reducing the possibility of coating peeling off.

[0039] In some embodiments, reference Figure 4 Along the first direction x that intersects the extension direction of the transition surface 11, the distance L1 between the adjacent edges of two adjacent guide units 120 satisfies: 0.03mm≤L1≤0.1mm.

[0040] In this embodiment, within the range of 0.03mm ≤ L1 ≤ 0.1mm, such as 0.03mm, 0.05mm, 0.08mm, and 0.1mm, a reasonable distance range ensures that the coating has sufficient space to naturally transition and fill within the interval area through surface tension, while also allowing the guiding function of the flow guiding unit 120 to be fully utilized, avoiding situations where the coating is locally too thick or too thin. If L1 is too large, the interval between adjacent flow guiding units 120 is too large, making it difficult to control the flow and diffusion of the liquid coating within the interval area, and the coating is difficult to uniformly cover the entire interval area, easily resulting in local coating gaps or uneven thickness. If L1 is too small, higher precision is required to ensure that the interval distance between the flow guiding units 120 meets the requirements, increasing processing difficulty and production costs.

[0041] In some embodiments, reference Figure 5 , Figure 6 The flow guiding structure 12 is provided on a portion of the transition surface 11. In the portion of the transition surface 11 where the flow guiding structure 12 is not provided, a cross section is made along the extension direction perpendicular to the transition surface 11. The outer contour of the transition surface 11 includes a first circular arc segment 111 and a second circular arc segment 112 that are continuously connected to each other, and the tangents at the connection between the two form an included angle α.

[0042] Specifically, taking a square cell housing 1 as an example, the transition surface 11 between the peripheral sides of the square cell housing 1 has a flow guiding structure 12, achieving a smooth geometric transition, reducing processing difficulty and improving production efficiency. Furthermore, the transition surface 11 between the peripheral side and the bottom surface uses a combination of a first arc segment 111 and a second arc segment 112 to ensure a smooth geometric transition while meeting the cell housing wall thickness requirements.

[0043] Understandably, when stamping the battery cell housing 1, due to the limitations of the stamping process, it is quite difficult to achieve a single large rounded corner transition surface while ensuring that the battery cell housing 1 reaches the required wall thickness.

[0044] In this embodiment, the combination of the first arc segment 111 and the second arc segment 112 makes it easier to control the forming accuracy of the two arc segments during the stamping process. By reasonably designing the radius, length and the included angle α of the tangent at the connection of the two arc segments, the continuous connection of the two arc segments ensures that the cell shell 1 reaches the required wall thickness, and the transition surface 11 can still maintain a relatively smooth transition, reducing the processing difficulty and improving production efficiency.

[0045] In some embodiments, reference Figure 6 The included angle α satisfies 156°≤α≤180°.

[0046] In this embodiment, when the included angle α is too small, the transition between the first arc segment 111 and the second arc segment 112 at the connection point becomes abrupt. When spraying liquid coating, the flow direction of the coating changes drastically when it flows to the connection area due to the large turning angle, resulting in poor flow of the coating in that area. When the included angle α is too large, i.e., the transition surface 11 is relatively close to a large fillet, the precision requirements for stamping are significantly increased, increasing the processing difficulty.

[0047] In some embodiments, reference Figure 6 The radius of the first arc segment 111 is Rb, and the radius of the second arc segment 112 is Rc, satisfying Rb=Rc≥0.05mm+L2, where L2 is the wall thickness of the outermost side 10 of the battery cell housing 1 with the largest area.

[0048] In this embodiment, Rb = Rc ≥ 0.05mm + L2 is set, and the radius of the arc is correlated with the wall thickness L2 of the outermost surface 10 of the cell housing 1, which has the largest area. This allows the design of the transition surface 11 to better fit the overall structure of the cell housing. During the stamping process, the radius of the arc of the transition surface can be reasonably determined while ensuring that the cell housing reaches the required wall thickness, thus reducing the processing difficulty. In some embodiments, reference Figure 6 The projection dimensions of the transition surface 11 in the orthogonal direction are h1 and h2, respectively. The radius of the first circular arc segment 111 is Rb, and the radius of the second circular arc segment 112 is Rc, satisfying h1=h2≥0.7Rb=0.7Rc.

[0049] In this embodiment, by setting h1=h2≥0.7Rb = 0.7Rc, it can be ensured that the projected size of the transition surface 11 in the orthogonal direction matches the radius of the arc, making the transition surface 11 present a more regular and symmetrical shape. This helps the coating to better conform to the shape of the surface during the flow process and distribute more evenly on the transition surface 11. In addition, it is also beneficial to disperse the external stress on the battery cell during use, reduce stress concentration, and improve the overall structural stability of the battery cell housing 1.

[0050] In some embodiments, the range of the projected dimensions h1 and h2 of the transition surface 11 in its orthogonal direction satisfies: |h1-h2|≤0.5 mm.

[0051] In this embodiment, when |h1-h2|≤0.5mm, for example 0.5mm, 0.4mm, or 0.3mm, it indicates that the projected dimensions of the transition surface 11 in the two orthogonal directions are not significantly different, exhibiting a relatively regular and symmetrical shape. By controlling the range of the projected dimensions of the transition surface 11 in the orthogonal directions, the uniform distribution of the coating on the surface can be ensured, avoiding the problem of localized excessive thickness or thinness of the coating caused by irregular surface shape.

[0052] In some embodiments, at least a portion of the outer surface of the cell housing 1 is provided with a microstructure, including at least one of pits, protrusions, and cracks, to increase the contact area between the coating and the outer surface.

[0053] Understandably, the outer surface of the battery cell housing 1 in this embodiment includes an outer surface 10 and a transition curved surface 11. In this embodiment, when coating is sprayed onto the outer surface of the battery cell housing 1 with microstructures, the coating will penetrate into the pits of these microstructures, or wrap around the protrusions, or fill the gaps in the cracks during the flow and drying curing process. Due to the presence of the microstructures, the contact between the coating and the outer surface of the battery cell housing 1 is no longer a simple planar contact, but forms a complex mechanical interlocking relationship, thereby increasing the contact area between the coating and the outer surface, and thus enhancing the adhesion between the coating and the outer surface of the battery cell housing 1.

[0054] In addition, during the flow process, the coating fills and spreads along the shape and direction of the microstructure, guiding the coating to be more evenly distributed on the outer surface of the cell housing 1, reducing the accumulation or dripping of the coating in local areas.

[0055] For example, the microstructure is a pit structure, which can accommodate a large amount of coating material. After the coating material cures, it forms strong mechanical anchoring points, significantly enhancing the adhesion between the coating and the battery cell housing 1. Furthermore, the numerous pits increase the actual contact area between the coating and the outer surface of the battery cell housing 1, making the bond between the coating and the substrate even tighter.

[0056] In some embodiments, the pits satisfy at least one of the following: pit diameter D, 20μm≤D≤1000μm; pit depth h3, 1μm≤h3≤30μm; and distance between adjacent pits L3, L3≤0.

[0057] Understandably, the pit diameter D satisfies 20μm ≤ D ≤ 1000μm, for example, 20μm, 22μm, 90μm, 100μm, 500μm, 800μm, 1000μm. The pit depth h3 satisfies 1μm ≤ h3 ≤ 30μm, for example, 1μm, 2μm, 9μm, 13μm, 24μm, 30μm. Furthermore, the spacing L3 between adjacent pits is set to L3 ≤ 0, meaning the pits overlap each other without gaps.

[0058] In this embodiment, the reasonable range of the pit diameter D and depth h3 is set so that it can accommodate a sufficient amount of paint to form an effective mechanical anchoring point, without affecting the filling effect of the paint or the bonding strength with the battery cell housing 1 due to excessively large or small sizes. That is, if the pit diameter is too small or the depth is too shallow, the paint cannot fill it sufficiently, making it difficult to form an effective anchor; if the pit diameter is too large or the depth is too deep, the paint may be uneven during the filling process, and the bonding strength with the housing will also be affected.

[0059] Furthermore, the coating penetrates into the pits and solidifies to form mechanical anchoring points. At the same time, the numerous densely overlapping pits increase the actual contact area between the coating and the outer surface of the battery cell housing 1, creating a complex mechanical interlocking relationship between the coating and the battery cell housing 1. This significantly enhances the adhesion between the coating and the outer surface of the battery cell housing 1 and reduces the risk of coating peeling off.

[0060] Furthermore, due to the densely overlapping distribution of the pits, the coating will fill and spread along the shape and direction of the pits during the flow process, guiding the coating to be more evenly distributed on the outer surface of the cell housing 1, reducing the accumulation or dripping of the coating in local areas, and making the coating thickness more uniform across the entire outer surface.

[0061] In some embodiments, at least two photocurable insulating layers are sequentially provided on the outer surface of the battery cell housing 1, and the thickness h4 of each photocurable insulating layer satisfies 10μm≤h4≤150μm.

[0062] Understandably, when forming a photocurable insulating coating on the outer surface of the cell housing 1, at least two photocurable insulating layers are sequentially applied. During the coating preparation process, the photocurable insulating coating is first sprayed onto the outer surface of the cell housing 1 using the main nozzle, forming a preliminary cured layer. After pre-curing, a compensation nozzle is used to supplement any potential localized printing defects, ensuring the coating completely covers the outer surface of the cell housing 1.

[0063] In this embodiment, a preliminary curing layer is first rapidly formed on the coating surface, ensuring the smoothness and thickness uniformity of the coating. Then, local printing defects are promptly repaired, further improving the integrity and quality of the coating.

[0064] In some embodiments, the outer surface of the cell housing 1 is provided with a plasma treatment layer to ensure that the surface energy of the cell housing 1 is not less than 50 mN / m.

[0065] In this embodiment, by using plasma treatment to directionally control the leveling properties of the coating, a uniform and smooth coating can be formed on the surface of the battery cell housing 1, reducing the local accumulation or sagging of the coating caused by surface energy differences.

[0066] Furthermore, since the surface energy of the battery cell casing 1 is no less than 50 mN / m after plasma treatment, the wettability between the coating and the surface of the battery cell casing 1 is significantly improved. The coating can better penetrate into the micro-uneven structure of the surface of the battery cell casing 1, forming a stronger mechanical interlocking effect. At the same time, the increase in surface energy also enhances the chemical bonding between the coating molecules and the surface molecules of the battery cell casing 1, thereby improving the adhesion between the coating and the battery cell casing 1.

[0067] Secondly, embodiments of this application provide a battery cell including the battery cell housing 1 described above. Therefore, it also includes the advantages of the battery cell housing 1 described above.

[0068] In the description of this application, 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. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0069] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0070] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0071] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A battery cell housing (1), characterized in that, include: Multiple outer surfaces (10); A transition surface (11) connects two adjacent outer surfaces (10); A flow guiding structure (12) is disposed on at least part of the transition surface (11) for guiding fluid to be uniformly distributed on the transition surface (11) by capillary action.

2. The cell housing (1) according to claim 1, characterized in that, The flow guiding structure (12) includes at least one flow guiding unit (120), which is arranged along the extension direction of the transition surface (11).

3. The cell housing (1) according to claim 2, characterized in that, The flow guiding unit (120) is a flow guiding groove (121), which is arranged along the extension direction of the transition surface (11).

4. The cell housing (1) according to claim 3, characterized in that, The sidewall of the guide groove (121) and the transition surface (11) are connected by a smooth transition.

5. The cell housing (1) according to claim 2, characterized in that, The flow guiding structure (12) includes a plurality of flow guiding units (120), which are arranged circumferentially along the transition surface (11).

6. The cell housing (1) according to claim 5, characterized in that, Along the first direction (x) that intersects the extension direction of the transition surface (11), the distance L1 between the adjacent edges of two adjacent flow guiding units (120) satisfies: 0.03mm≤L1≤0.1mm.

7. The cell housing (1) according to any one of claims 1 to 6, characterized in that, The flow guiding structure (12) is disposed on a portion of the transition surface (11); in the portion of the transition surface (11) where the flow guiding structure (12) is not disposed, a cross section is made along the extension direction perpendicular to the transition surface (11), and the outer contour of the transition surface (11) includes a first arc segment (111) and a second arc segment (112) that are continuously connected to each other, and the tangents at the connection between the two form an angle α.

8. The cell housing (1) according to claim 7, characterized in that, Meet at least one of the following: a-1) The included angle α satisfies 156°≤α≤180°; a-2) The radius of the first arc segment (111) is Rb, and the radius of the second arc segment (112) is Rc, satisfying Rb=Rc≥0.05mm+L2, where L2 is the wall thickness of the outer side (10) with the largest area of ​​the battery cell housing (1); a-3) The projection dimensions of the transition surface (11) in the orthogonal direction are h1 and h2, respectively. The radius of the first arc segment (111) is Rb, and the radius of the second arc segment (112) is Rc, satisfying h1=h2≥0.7Rb=0.7Rc; The range of the projection dimensions h1 and h2 of the transition surface (11) in its orthogonal direction (a-4) satisfies: |h1-h2| ≤0.5 mm.

9. The cell housing (1) according to any one of claims 1 to 6, characterized in that, Meet at least one of the following: b-1) The outer surface of the battery cell housing (1) is provided with a microstructure, the microstructure including at least one of pits, protrusions and cracks, to increase the contact area between the coating and the outer surface; b-2) The outer surface of the battery cell housing (1) is provided with a plasma treatment layer to ensure that the surface energy of the battery cell housing (1) is not less than 50 mN / m.

10. The cell housing (1) according to claim 9, characterized in that, The pit satisfies at least one of the following: c-1) Diameter of the pit D, 20μm≤D≤1000μm; c-2) The pit depth h3, 1μm≤h3≤30μm; c-3) There should be at least partial overlap between adjacent pits.

11. The cell housing (1) according to any one of claims 1 to 6, characterized in that, The outer surface of the battery cell housing (1) is provided with at least two photocurable insulating layers in sequence, and the thickness h4 of each photocurable insulating layer satisfies 10μm≤h4≤150μm.

12. A battery cell, characterized in that, Includes the cell housing (1) as described in any one of claims 1 to 11 above.

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