Pouch cell and power consuming device

Abstract

The utility model relates to battery technical field discloses a kind of soft package battery and electric device.The soft package battery includes electric core and shell, shell includes oppositely arranged first shell and second shell, first shell and second shell are sealedly connected to form sealing edge, sealing edge includes first sealing edge, and first sealing edge includes at least two laminated sealing sections formed by bending;The outside of first sealing edge is bonded with fastening band, and fastening band is used to keep the bending state of first sealing edge;Wherein, the width of fastening band is L, the bonding size between fastening band and first sealing edge is d, satisfy, 85mm 2 ≤L*d≤400mm 2 The utility model can prevent the rebound of first sealing edge and reduce the short circuit risk of first sealing edge and accessory metal parts.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to pouch batteries and electrical devices. Background Technology

[0002] With the rapid development of new energy technologies, batteries are being used more and more widely. Batteries have been applied in fields such as electric vehicles.

[0003] Currently, pouch batteries are widely used in the battery industry due to their simple manufacturing process and wide range of applications. However, pouch batteries have a risk of short circuits caused by metal leakage at the sealed edge of the casing, which can easily cause the sealed edge of the battery casing to overlap with nearby metal parts, seriously affecting the battery's lifespan. Utility Model Content

[0004] In view of this, the present invention provides a soft-pack battery and an electrical device to solve the problem of short circuit caused by the overlap between the sealing edge of the soft-pack battery and the metal parts of the accessory, which affects the battery's service life.

[0005] In a first aspect, this utility model provides a soft-pack battery, comprising: a battery cell and a casing, wherein the casing houses the battery cell, the casing includes a first casing and a second casing disposed opposite to each other along a first direction, the casing includes a body portion and a flange portion, the body portion is disposed opposite to the battery cell, the flange portion is disposed on the outer periphery of the body portion, the flange portions of the first casing and the second casing are sealed together to form a sealing edge, the sealing edge includes a first sealing edge extending away from the battery cell along a third direction, the first sealing edge including at least two stacked sealing segments formed by bending; a fastening band, the fastening band being adhered to the outside of the first sealing edge, the fastening band being used to keep the first sealing edge in a bent state; wherein, along the second direction, the width of the fastening band is L, and along the first direction, the adhesion dimension between the fastening band and the first sealing edge is d, the units of L and d are mm, satisfying 85mm. 2 ≤L*d≤400mm 2 The first direction, the second direction, and the third direction are perpendicular to each other.

[0006] Beneficial effects: The first sealing edge includes at least two stacked sealing segments formed by bending, which conceals the exposed intermediate metal layer of the first sealing edge, thereby isolating the intermediate metal layer from nearby metal components and preventing short circuits caused by contact between the metal layer and nearby metal components, thus improving battery life. The first sealing edge is secured with a fastening band, effectively preventing springback and cracking, thereby reliably isolating the metal layer from nearby metal components. (85mm) 2 ≤L*d≤400mm 2This not only prevents the first sealing edge from rebounding and reduces the risk of short circuit when the first sealing edge overlaps with the metal parts, but also prevents the cell from falling off due to excessive force when tightening the first sealing edge, which could lead to a decrease in battery energy density or the risk of lithium plating.

[0007] Secondly, this utility model also provides an electrical device, including the soft-pack battery as described above.

[0008] Since the electrical device includes the pouch battery provided by the utility model, it has the same beneficial effects as the pouch battery, and will not be described in detail here. Attached Figure Description

[0009] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the structure of the soft-pack battery according to an embodiment of the present invention; Figure 2 This is a side view of the soft-pack battery according to an embodiment of the present invention; Figure 3 This is a partially enlarged schematic diagram of the soft-pack battery according to an embodiment of the present invention; Figure 4 This is a simplified structural diagram of the fastening strap in both the bonded and unfolded states according to an embodiment of the present invention. Figure 5 This is a simplified structural diagram of the first sealing edge in both the bent and unfolded states according to an embodiment of the present invention. Figure 6 This is a schematic diagram of the structure of the soft-pack battery after assembly according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of a soft-pack battery after assembly according to another embodiment of the present invention.

[0011] Explanation of reference numerals in the attached figures: 10-Battery cell; 11-First tab; 12-Second tab; 20-Housing shell; 201-First sealing edge; 201a-First folding section; 201b-Second folding section; 202-Second sealing edge; 203-Third sealing edge; 204-Integral connecting part; 21-First housing shell; 211-First outer surface; 22-Second housing shell; 221-Second outer surface; a3-First folding end; a4-Second folding end; a5-Tail end; 30 - Fastening band; 30a - First end; 30b - Second end; 30c - First contact portion; 30d - Second contact portion; X - First direction; Y - Second direction; Z - Third direction. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0013] Currently, the sealed edge of a pouch battery is prone to short circuits due to contact with nearby metal parts, which seriously affects the battery's lifespan.

[0014] Research has found that the exposed metal layer of a soft-pack battery after the sealing edge is cut is prone to creeping and overlapping with the tabs, causing the entire metal layer of the battery casing to become charged. The charged metal layer is prone to short circuits with the nearby metal plate or the tabs of other batteries, affecting the battery's lifespan.

[0015] To address this, by bending the sealing edge to form at least two stacked sealing sections, the exposed metal layer after the sealing edge is cut is concealed, thus isolating the metal components. Even if the metal layer is charged when it overlaps with the electrode tab, the risk of a short circuit between the sealing edge and nearby metal components can be effectively prevented, improving battery life. Further research revealed that due to stress concentration, the sealing edge is prone to springing back under vibration. After springing back, it is prone to cracking, leading to failure of the seal between the sealing edge and nearby metal components, as well as seal failure, resulting in a short circuit. To address this, fastening the sealing edge with a fastening tape effectively prevents springing back, thereby reliably isolating nearby metal components and ensuring a reliable seal.

[0016] The following is combined with Figures 1 to 7 The following describes embodiments of the present invention.

[0017] According to an embodiment of the present invention, in a first aspect, a soft-pack battery is provided, including a battery cell 10 and a housing 20. The housing 20 houses the battery cell 10. The housing 20 includes a first housing 21 and a second housing 22 disposed opposite to each other along a first direction X. The housing 20 includes a body portion and a flange portion. The body portion is disposed opposite to the battery cell 10. The flange portion is disposed on the outer periphery of the body portion. The flange portions of the first housing 21 and the second housing 22 are sealed together to form a sealing edge. The sealing edge includes a first sealing edge 201 extending away from the battery cell 10 along a third direction Z. The first sealing edge 201 includes at least two stacked sealing segments formed by bending. A fastening band 30 is adhered to the outside of the first sealing edge 201 to fix the first sealing edge 201 so that the first sealing edge 201 remains in a bent state. The width of the fastening band 30 along the second direction Y is L. The bonding dimension between the fastening band 30 and the first sealing edge 201 along the first direction X is d. The units of L and d are mm, and d satisfies 85 mm. 2 ≤L*d≤400mm 2 The first direction X, the second direction Y, and the third direction Z are all perpendicular to each other. For example, the first direction X can be the width direction of the housing 20, the second direction Y can be the length direction of the housing 20, and the third direction Z can be the thickness direction of the housing 20.

[0018] The battery is a pouch cell. Cell 10 can be either stacked or wound.

[0019] The battery cell 10 includes a positive electrode, a negative electrode, and a separator disposed between the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer disposed on at least one surface of the positive current collector. The negative electrode includes a negative current collector and a negative active material layer disposed on at least one surface of the negative current collector.

[0020] The positive current collector can be made of metal foil. For example, the metal foil can be made of aluminum with a silver-plated surface, stainless steel with a silver-plated surface, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc.

[0021] As an example, the positive electrode active material in the positive electrode active material layer may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. Lithium phosphate may include, but is not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also abbreviated as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Lithium transition metal oxide may include, but is not limited to, at least one of lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and their modified compounds.

[0022] The negative electrode current collector can be made of metal foil. For example, the metal foil can be made of silver-treated aluminum or stainless steel, copper, aluminum, nickel, carbon electrode, nickel or titanium, etc.

[0023] The negative electrode active material in the negative electrode active material layer can be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. 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. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys.

[0024] The membrane material can include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The membrane can be a single-layer film or a multi-layer composite film. When the membrane is a multi-layer composite film, the materials of each layer can be the same or different.

[0025] The outer shell 20 is a soft shell. For example, it can be an aluminum-plastic film. The aluminum-plastic film may include an inner adhesive layer (heat-sealing layer), a middle metal layer (aluminum foil barrier layer), and an outer protective layer. The inner adhesive layer can be made of polypropylene (CPP) or polyethylene, or other materials resistant to electrolyte corrosion. The middle layer can be made of pure aluminum or aluminum-iron alloy, or other materials used to block moisture and oxygen. The outer layer can be made of nylon (ON) or polyester (PET), and a PET layer may also be added.

[0026] The flange edges (flanged portions) of the first housing 21 and the flange edges (flanged portions) of the second housing 22 are bonded together (e.g., by adhesive) or heat-fused together through their respective inner adhesive layers (heat-sealing layers) to form the sealing edge of the housing 20. See, for example... Figure 1The sealing edges of the housing 20 include a first sealing edge 201, a second sealing edge 202, and a third sealing edge 203. The first sealing edge 201 extends away from the battery cell 10 along a third direction Z; the second sealing edge 202 and the third sealing edge 203 extend away from the battery cell 10 along a second direction Y and in a direction opposite to each other. The housing 20 also includes an integral connecting portion 204 on the side opposite to the first sealing edge 201 along a third direction Z, and the first housing 21 and the second housing 22 are connected by the integral connecting portion 204. The first housing 21 and / or the second housing 22 have grooves, which may be formed by stamping.

[0027] The first sealing edge 201 includes a bent section forming at least two stacked sealing segments, such that the first sealing edge 201 has its tail end a5 exposed by cutting off the intermediate metal layer. Figure 3 As shown, the tail end a5 is hidden, meaning it does not directly face the nearby metal component. This metal component can be a metal structure on an adjacent battery, the casing wall of the battery pack, or other metal parts. The number of bends and the shape of the first sealing edge 201 are unlimited, as long as the tail end a5 with the exposed intermediate metal layer does not directly face the metal component of the accessory. Figure 3 An example is shown where the first sealing edge 201 is bent twice to form a folded segment with two layers of sealing sections. It is understood that the number of bends can be three, four, or more, thereby forming more layers of sealing sections. The first sealing edge 201 can be bent towards the side closer to the battery cell or towards the side away from the battery cell. The first sealing edge 201 can be curled after bending.

[0028] There can be one or more fastening straps 30. When there are multiple fastening straps 30, they can be spaced apart along the second direction Y. The method by which the fastening straps 30 secure the bent portion is not limited, as long as the bent portion is kept bent and prevented from springing back. For example, when there is one battery, the fastening strap 30 can be wrapped around the bent portion and adhered to the housing 20 to restrain the bent portion and prevent it from springing back. When there are multiple batteries arranged along the third direction Z, the fastening strap 30 can be fixed to the two outermost batteries along the third direction Z and adhered to the bent portions of multiple batteries, so that multiple bent portions can be restrained simultaneously by one fastening strap 30.

[0029] The fastening tape 30 can be an adhesive tape, including an adhesive layer and an insulating layer. The adhesive layer can be made of one or more of the following materials: acrylic, silicone, and pressure-sensitive rubber. The insulating layer, or base layer, can be made of one or more of the following materials: polyester (PET), polyimide (PI), polypropylene (PP), and polyethylene (PE).

[0030] L represents the width of a single fastening strap (30mm). L can be 10mm to 30mm, such as any one of 10mm, 12mm, 15mm, 20mm, 25mm, or 30mm, or any combination thereof.

[0031] d can be 5mm to 15mm, such as any one of 5mm, 6mm, 8mm, 10mm, 12mm, 13mm, 14mm, 15mm or any two of them.

[0032] If L*d is too small, the binding force of the fastening band 30 on the first sealing edge 201 is too weak, resulting in a high risk of the first sealing edge 201 rebounding, which could lead to a high risk of short circuit between the first sealing edge 201 and the metal parts, and a high risk of sealing failure due to cracking of the first sealing edge 201 after rebounding. If L*d is too large, the binding force of the fastening band 30 on the first sealing edge 201 is too strong, and the first sealing edge 201 may press against the internal cell during battery cycle expansion, which could easily lead to cell material loss, a decrease in battery energy density, or a risk of lithium plating. Therefore, 85mm 2 ≤L*d≤400mm 2 This not only prevents the first sealing edge 201 from rebounding, reducing the risk of short circuit between the first sealing edge 201 and the metal parts, and reducing the risk of seal failure after the first sealing edge 201 rebounds, but also prevents the cell from falling off due to excessive force when tightening the first sealing edge 201, resulting in a decrease in battery energy density or the risk of lithium plating.

[0033] In some embodiments, reference is made together with Figure 3 and Figure 4 The first housing 21 has a first outer surface 211 on the side opposite to the second housing 22 along the first direction X. The first sealing edge 201 has a first folded section 201a and a second folded section 201b. The first folded section 201a is bent toward the side of the first direction X, and the second folded section 201b is bent toward the other side of the first direction X. The first sealing edge 201 has a first folded end a3, a second folded end a4 and a tail end a5.

[0034] The first folded end a3 is the folded end formed after the first sealing edge 201 is bent for the first time, and it is connected to the shell body; the second folded end a4 is the folded end formed after the first sealing edge 201 is bent for the second time, and it is connected to the first folded segment 201a and the second folded segment 201b; the tail end a5 is the end with an exposed intermediate metal layer after cutting.

[0035] The first end 30a of the fastening band 30 along its unfolding direction is bonded to the first outer surface 211. The first outer surface 211 is the surface adjacent to the lead-out end face of the first sealing edge 201. Preferably, the first outer surface is the large surface of the battery casing to ensure reliable fixing strength.

[0036] The fastening band 30 also has a first contact portion 30c that adheres to the first folded end a3. Along the unfolding direction of the fastening band 30, the distance between the first end 30a and the first contact portion 30c is C1, satisfying 10mm ≤ C1 ≤ 60mm. C1 can be any one of 10mm, 20mm, 30mm, 40mm, 50mm, and 60mm, or a value between any two of these.

[0037] If the distance C1 between the first end 30a and the first contact portion 30c is too small, the bonding size between the fastening band 30 and the first outer surface 211 is too small, resulting in poor bonding strength and a high risk of bonding failure. This leads to a high risk of the first sealing edge 201 rebounding, which in turn leads to a high risk of short circuit between the first sealing edge 201 and the metal part. If C1 is too large, the bonding size of the fastening band 30 on the first outer surface 211 of the housing 20 is large, resulting in a large binding force on the first outer surface 211. This leads to a high risk of material falling off the cell corresponding to the first outer surface 211 during battery cycle expansion, resulting in a decrease in battery energy density or a risk of lithium plating. Therefore, 10mm≤C1≤60mm can prevent the first sealing edge 201 from rebounding, reduce the risk of short circuit between the first sealing edge 201 and the metal part, and also prevent cell material falling off due to the large binding force of the fastening band on the first outer surface 211, as well as the risk of a decrease in battery energy density or lithium plating.

[0038] In some embodiments, the fastening band 30 further has a second contact portion 30d that is bonded to the second folded end a4. Along the unfolding direction of the fastening band 30, the dimension between the first contact portion 30c and the second contact portion 30d is C2, satisfying 0.67≤C1 / C2≤4. C1 / C2 can be any one of 0.67, 1, 2, 2.5, 3, 4, or any value between two of them.

[0039] The first folding segment 201a located between the first folding end a3 and the second folding end a4 in the first sealing edge 201 has a high risk of rebound. Therefore, if the distance of the first folding segment 201a is large, the dimension C1 of the distance between the first end 30a and the first contact portion 30c also needs to be large to ensure that the first sealing edge 201 does not rebound. If C1 / C2 is too small (C1 is relatively small, C2 is relatively large), the bonding size between the fastening band 30 and the first outer surface 211 is too small, resulting in poor bonding strength and a high risk of bonding failure, leading to a high risk of short circuit when the first sealing edge 201 overlaps with the metal part. If C1 / C2 is too large (C1 is relatively large, C2 is relatively small), the bonding size between the fastening band 30 and the first outer surface 211 of the housing 20 is too large, which can easily cause the cell to fall off the part corresponding to the first outer surface 211 during battery cycle expansion, as well as a decrease in battery energy density or a risk of lithium plating. Therefore, 0.67≤C1 / C2≤4 can prevent the first sealing edge 201 from rebounding, reducing the risk of short circuit when the first sealing edge 201 overlaps with the metal part, and can also prevent excessive force when fastening the first sealing edge 201 from causing the cell to fall off, as well as a decrease in battery energy density or a risk of lithium plating.

[0040] In some embodiments, refer to Figure 3 and Figure 4 The portion of the fastening band 30 located between the first end 30a and the first contact portion 30c is the first fastening section. The bonding dimension between the first fastening section and the first outer surface 211 is C3, which satisfies 5mm≤C3≤50mm. C3 can be any one of 5mm, 10mm, 20mm, 22mm, 30mm, 40mm, 45mm, and 50mm, or any value between two of them.

[0041] If C3 is too small, the bonding size between the fastening band 30 and the first outer surface 211 is too small, resulting in poor bonding strength, a high risk of bonding failure, a high risk of the first sealing edge 201 rebounding, and a high risk of short circuit between the first sealing edge 201 and the metal part. If C3 is too large, the bonding size between the fastening band 30 and the first outer surface 211 of the housing 20 is too large, which can easily cause the cell to fall off the part corresponding to the first outer surface 211 during battery cycle expansion, resulting in a decrease in battery energy density or a risk of lithium plating. Therefore, 5mm≤C3≤50mm can prevent the first sealing edge 201 from rebounding, reduce the risk of short circuit between the first sealing edge 201 and the metal part, and also prevent excessive force in fastening the first sealing edge 201 from causing the cell to fall off, resulting in a decrease in battery energy density or a risk of lithium plating.

[0042] In some embodiments, the second housing 22 has a second outer surface 221 facing away from the first housing 21 along a first direction X. The second end 30b of the fastening band 30 along its unfolding direction is bonded to the second outer surface 221. The distance between the second end 30b and the second contact portion 30d along the unfolding direction of the fastening band 30 is C4, satisfying 10mm ≤ C4 ≤ 50mm. C4 can be any one of 10mm, 20mm, 30mm, 40mm, 45mm, and 50mm, or a value between any two of these.

[0043] If the distance C4 between the second end 30b and the second contact portion 30d is too small, the bonding size between the fastening band 30 and the second outer surface 221 will be too small, resulting in poor bonding strength, a high risk of bonding failure, a high risk of the first sealing edge 201 rebounding, and a high risk of short circuit between the first sealing edge 201 and the metal part. If C4 is too large, the bonding size between the fastening band 30 and the second outer surface 221 of the housing 20 will be large, which may cause the cell to fall off the part corresponding to the second outer surface 221 during battery cycle expansion, resulting in a decrease in battery energy density or a risk of lithium plating. Therefore, 10mm≤C4≤50mm can prevent the first sealing edge 201 from rebounding and reduce the risk of short circuit between the first sealing edge 201 and the metal part, and can also prevent the cell from falling off due to excessive fastening force, resulting in a decrease in battery energy density or a risk of lithium plating.

[0044] In some embodiments, along the unfolding direction of the first sealing edge 201, the distance between the second folded end a4 and the tail end a5 is G, in mm, and satisfies 170 mm. 3 ≤G*(L*d)≤2400mm 3 G*(L*d) can be 170mm. 3 300mm 3 500mm 3 1000mm 3 1200mm 3 1500mm 3 2000mm 3 2400mm 3 The value is any one of the values ​​or any two of them. The size range of G is 2mm to 6mm.

[0045] The smaller G is, that is, the smaller the size of the second folding segment 201b, the higher the risk of the first sealing edge 201 rebounding. The rebound of the first sealing edge 201 can be directly prevented by controlling the size of G, or the rebound of the first sealing edge 201 can be indirectly controlled by the above-mentioned L*d.

[0046] If G*(L*d) is too small, the size of the second folding segment 201b is too small, and the binding force of the fastening band 30 on the first sealing edge 201 is too weak, resulting in a high risk of springback of the first sealing edge 201 and a high risk of short circuit between the first sealing edge 201 and the metal parts. If G*(L*d) is too large, the size of the second folding segment 201b is too large, occupying a lot of space and resulting in low volumetric energy density. Furthermore, the binding force of the fastening band 30 on the first sealing edge 201 is too strong, causing the first sealing edge 201 to press against the internal battery cell during battery cycle expansion, which can easily lead to cell material loss, decreased battery energy density, or the risk of lithium plating. Therefore, 170mm 3 ≤G*(L*d)≤2400mm 3 This not only prevents the first sealing edge 201 from rebounding and reduces the risk of short circuit between the first sealing edge 201 and the metal parts, but also prevents the cell from falling off due to excessive force when tightening the first sealing edge 201, which could lead to a decrease in battery energy density or the risk of lithium plating. It can also help improve the volumetric energy density of the battery.

[0047] In some embodiments, refer to Figure 2 The first end 30a and the second end 30b are staggered along the third direction Z, and the stagger distance is H, which satisfies 0.1mm≤H≤5mm. H can be any one of 0.1mm, 1mm, 2mm, 3mm, 4mm, 5mm or any value between two of them.

[0048] The smaller the value of H, the better the alignment of the two ends of the fastening band 30, the smaller the dimensional difference between the fastening band 30 and the first outer surface 211 and the second outer surface 221, the better the bonding consistency, and the less likely it is to fail. If H is too large, the dimensional difference between the fastening band 30 and the first outer surface 211 and the second outer surface 221 will be too large, resulting in poor bonding consistency. This will lead to a higher risk of bonding failure on the side with the smaller bonding size, and the first sealing edge 201 will not be effectively restrained. Ultimately, this will cause the first sealing edge 201 to spring back, which will then lead to a short circuit between the first sealing edge 201 and the metal part. Therefore, 0.1mm≤H≤5mm can ensure good alignment of the two ends of the fastening band 30, good bonding consistency between the fastening band 30 and the first outer surface 211 and the second outer surface 221, high bonding reliability, and reduce the risk of short circuit between the first sealing edge 201 and the metal part due to springback.

[0049] In some embodiments, along the unfolding direction of the fastening band 30, the fastening band 30 has a first end 30a and a second end 30b, and the housing 20 has a side surface opposite to the first sealing edge 201 along the third direction Z, to which the first end 30a and / or the second end 30b are bonded. This side surface is the outer surface of the integral connecting portion 204 of the housing 20.

[0050] This configuration can further enhance the bonding strength of the fastening band 30 and improve the fastening reliability of the first sealing edge 201.

[0051] In some embodiments, the sealing edge further includes a second sealing edge 202 and a third sealing edge 203, which are disposed opposite to each other along the second direction Y. A first sealing edge 201 connects the second sealing edge 202 and the third sealing edge 203. The battery cell 10 includes a first electrode 11, which extends from the second sealing edge 202. Along the second direction Y, the shortest interval distance between the fastening band 30 and the edge of the second sealing edge 202 near the edge of the battery cell 10 is M1, satisfying 15mm ≤ M1 ≤ 80mm. M1 can be any one of 15mm, 25mm, 30mm, 40mm, 50mm, 60mm, 70mm, and 80mm, or a value between any two of them.

[0052] During battery cycling, the first tab 11 generates heat, and a significant amount of gas is also generated inside the battery near the first tab 11. If M1 is too small, the fastening band 30 will be too close to the first tab 11, increasing the risk of the fastening band 30 failing due to heat. If M is too large, the portion of the first sealing edge 201 near the first tab 11 will be at high risk of springing back due to gas rupture. Therefore, 15mm ≤ M1 ≤ 80mm can prevent the fastening band 30 from failing due to heat and also prevent the first sealing edge 201 from springing back due to gas rupture.

[0053] In some embodiments, the battery cell 10 further includes a second tab 12 extending from the third sealing edge 203.

[0054] This configuration, compared to having two tabs drawn from the same sealing edge, can disperse the heat generated by the tabs during battery cycling, preventing seal failure due to excessively high local temperature of the casing 20, thereby reducing the risk of the first sealing edge 201 rebounding.

[0055] In some embodiments, multiple fastening straps 30 are provided, and the multiple fastening straps 30 are spaced apart along the second direction Y, with a spacing range of P, satisfying 50mm≤P≤200mm. P can be any one of 50mm, 60mm, 100mm, 130mm, 150mm, 200mm, or any value between any two.

[0056] If P is too large, the fastening band 30 will have a poor binding effect on the first sealing edge 201, resulting in a high risk of the first sealing edge 201 rebounding, which in turn will lead to a high risk of short circuit between the first sealing edge 201 and the metal part. If P is too small, the battery will be subject to a large binding force from the fastening band 30, resulting in a small space for battery cycle expansion, leading to a high risk of cell wear and material loss, and a decrease in battery energy density. Therefore, 50mm≤P≤200mm can prevent the first sealing edge 201 from rebounding and causing a short circuit between the first sealing edge 201 and the metal part, and can also prevent the battery cycle expansion caused by excessive binding force due to insufficient P, which would lead to cell wear and material loss and a decrease in battery energy density.

[0057] In some embodiments, the sum of the widths of the plurality of fastening straps 30 along the second direction Y is L', and the length of the housing 20 along the second direction Y is E, satisfying 0.1≤L' / E≤0.4. L' can be 50mm~200mm. E can be 300mm~800mm.

[0058] If L' / E is too small, L' has a small proportion, resulting in poor binding effect of the fastening band 30 on the first sealing edge 201. This leads to a high risk of the first sealing edge 201 rebounding, which in turn leads to a high risk of short circuit between the first sealing edge 201 and the metal part. If L' / E is too large, the battery is bound by a large force of the fastening band 30, resulting in a small space for battery cycle expansion. This leads to a high risk of cell wear and material loss, and a decrease in battery energy density. Therefore, 0.1≤L' / E≤0.3 can prevent the first sealing edge 201 from rebounding and short circuit between the first sealing edge 201 and the metal part, and can also prevent cell wear and material loss during battery cycle expansion due to excessive binding force caused by an excessively small P, which leads to a decrease in battery energy density.

[0059] In some embodiments, the housing 20 has a midpoint O along the second direction Y, and the distance between the edge of the fastening band 30 closest to the midpoint O and the midpoint O is M2, satisfying 3mm ≤ M2 ≤ 50mm. M2 is a value between any one or any two of 3mm, 10mm, 15mm, 20mm, 30mm, 40mm, and 50mm.

[0060] Generally, the closer the battery is to the center O of the casing 20, the more severe the gas generation and the greater the expansion. Therefore, the fastening band 30 can be positioned away from this center O to prevent it from sticking and reducing the battery's expansion space. If M2 is too large, the fastening band 30 will not effectively restrain the first sealing edge 201, resulting in a high risk of the first sealing edge 201 rebounding, which in turn leads to a high risk of short circuit between the first sealing edge 201 and the metal part. If M2 is too small, it will reduce the battery's expansion space, leading to a high risk of cell wear and material loss, and a decrease in battery energy density. Therefore, 3mm ≤ M2 ≤ 50mm can prevent the first sealing edge 201 from rebounding and causing a short circuit between the first sealing edge 201 and the metal part, and also prevent cell wear and material loss during battery cycle expansion due to excessive restraint force on the center O of the casing 20 caused by an excessively small M2, thus reducing battery energy density.

[0061] In some embodiments, the housing 20 has a midpoint O along the second direction Y, where a fastening band 30 is bonded. The battery cell 10 is wrapped with an insulating film of thickness F1, satisfying 0.01mm ≤ F1 ≤ 0.1mm. F1 can be any one of 0.01mm, 0.05mm, 0.06mm, 0.8mm, 0.1mm, or a value between any two of them.

[0062] With the fastening band 30 bonded at the middle position O, the thickness of the insulating film provides space for battery expansion, thus buffering the expansion. If F1 is too large, the insulating film thickness is too large, which is not conducive to heat dissipation; if F1 is too small, it cannot effectively buffer the battery expansion. Therefore, 0.01mm≤F1≤0.1mm can buffer the battery expansion, reduce the risk of cell wear and material loss, and avoid affecting battery heat dissipation.

[0063] In some embodiments, the fastening band 30 has an adhesive layer and an insulating layer. The adhesive layer is bonded to the first sealing edge 201, and the insulating layer is located on the side of the adhesive layer away from the housing. The thickness of the adhesive layer is N1, satisfying 0.01mm ≤ N1 ≤ 0.15mm. N1 is a value between any and any two of 0.01mm, 0.05mm, 0.08mm, 0.1mm, 0.13mm, and 0.15mm. The adhesive layer is the inner bonding layer, and the insulating layer is the outer protective layer.

[0064] The thicker the adhesive layer (N1), the more compression allowance it provides during bonding, resulting in higher bond strength. However, it should not be too thick, as excessive thickness takes up space and is prone to scratching and tearing. Therefore, a thickness of 0.01mm ≤ N1 ≤ 0.15mm is ideal, as it improves bond strength while preventing seal failure due to excessive thickness causing scratching and tearing.

[0065] In some embodiments, the housing 20 includes an inner adhesive layer, an intermediate metal layer, and an outer protective layer. The intermediate metal layer is disposed between the inner adhesive layer and the outer protective layer. The outer protective layer is located on the outermost side of the intermediate metal layer away from the battery cell 10. The thickness of the intermediate metal layer is F2, where F2 is in μm. The thickness of the fastening band 30 is N2, where N2 is in mm. The following condition must be met: 0.1 ≤ F2 / N2 ≤ 2. F2 / N2 can be any one of 0.1, 0.5, 1, 1.3, 1.5, 2, or any combination thereof. For example, 35 μm ≤ F2 ≤ 60 μm; 0.02 mm ≤ N2 ≤ 6 mm.

[0066] The outer protective layer serves as the outer insulation layer, and its material can be one or more of the following: polycaprolactam (nylon 6), PET (polyethylene terephthalate), polybutylene succinate, etc. The intermediate metal layer can be one or more of the following metals or alloys: aluminum, aluminum alloy, copper, nickel, etc. The inner adhesive layer serves as the inner insulation layer, and its material can be one or more of the following: polypropylene film (PP) and cast polypropylene film (CPP).

[0067] The nylon layer is responsible for maintaining the shape stability of the aluminum-plastic film, ensuring that the film does not deform during the manufacturing process of lithium-ion batteries.

[0068] The primary function of the intermediate metal layer is waterproofing. Lithium batteries are extremely sensitive to moisture, and the packaging film must effectively prevent water vapor intrusion. Nylon itself is not waterproof and cannot meet this requirement, while aluminum, after reacting with oxygen in the air, forms a dense oxide film, thus preventing water vapor penetration and protecting the inside of the battery cell. In addition, the aluminum layer also provides the necessary plasticity during the aluminum-plastic film molding process to meet the requirements of the perforation process.

[0069] The PP layer, or polypropylene layer, has the property of melting at high temperatures and being adhesive. The battery's thermal sealing process mainly relies on the PP layer melting and bonding together when the end caps are heated, followed by curing and bonding during cooling.

[0070] The thicker the fastening band 30 (N2), the greater the binding force on the shell 20. Consequently, the thickness of the intermediate metal layer also needs to be thicker to prevent deformation or damage to the intermediate metal layer due to excessive thinness. By controlling the thickness difference between the two within a suitable range of 0.1≤F2 / N2≤0.13, the risk of deformation or damage to the intermediate metal layer can be reduced.

[0071] In some embodiments, the length of the first sealing edge 201 along the unfolding direction is B, which satisfies 8mm≤B≤20mm. B can be any one of 8mm, 10mm, 12mm, 15mm, 20mm, or any value between two of them.

[0072] If B is too small, the first sealing edge 201 will be broken by the gas inside the battery, resulting in a high risk of the first sealing edge 201 rebounding. If B is too large, it will occupy a lot of space, resulting in low space utilization and low volumetric energy density. Therefore, 8mm≤B≤20mm can reduce the risk of the first sealing edge 201 being broken by the gas inside the battery and rebounding, and is also conducive to improving space utilization and increasing volumetric energy density.

[0073] In some embodiments, the first sealing edge 201 includes a first sealing segment, the length of which along the unfolding direction is D, satisfying 6mm ≤ D ≤ 15mm. D can be any one of 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 14mm, and 15mm, or a value between any two of them. The first sealing segment is the area where the first sealing edge 201 is heat-sealed and fused.

[0074] If the length D of the first sealing section is too small, the sealing effect will be poor, and it will be easily broken by the gas inside the battery, resulting in a high risk of the first sealing edge 201 rebounding. If the length D of the first sealing section is too large, it will occupy a lot of space, resulting in low space utilization and low volumetric energy density. Therefore, 6mm≤D≤15mm can reduce the risk of the first sealing edge 201 rebounding due to the gas inside the battery, and also help to improve space utilization and increase volumetric energy density.

[0075] In some embodiments, multiple batteries are provided, and a fastening band 30 is adhered to the first sealing edge 201 of each battery. This effectively secures the first sealing edge 201 of each battery, reducing the risk of short circuits between the battery and nearby metal components.

[0076] Multiple fastening straps 30 can be attached to each battery. Or, at least two batteries can be attached to one fastening strap 30.

[0077] In some embodiments, refer to Figure 6 Each battery is attached with a fastening band 30, and all fastening bands 30 are attached to a single battery. When multiple fastening bands 30 are attached to each battery, the risk of springback of the first sealing edge 201 is significantly reduced; therefore, L*d can be smaller, such as 60mm. 2 ≤L*d≤300mm 2 This also ensures that the first sealing edge 201 does not spring back and reduces the size of the fastening strip 30, thus lowering costs.

[0078] In some embodiments, refer to Figure 7 A fastening band 30 is used to bond the first sealing edge 201 of at least two batteries. This reduces the amount of fastening band 30 used and lowers costs. Figure 7 Five batteries are shown, with the first sealing edge 201 of all five batteries secured by a fastening band 30. It is understood that it is also possible for two of the five batteries to have their first sealing edge 201 secured by one fastening band 30, while the first sealing edge 201 of the other three batteries is secured by another fastening band 30.

[0079] According to an embodiment of the present invention, an electrical device is also provided, including the soft-pack battery mentioned in any of the above embodiments.

[0080] Battery devices can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. Vehicles can be gasoline-powered vehicles, natural gas-powered vehicles, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc.

[0081] Electrical devices can include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0082] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application, are intended to cover non-exclusive inclusion. In the description of embodiments of this application, technical terms such as "first," "second," etc., are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of embodiments of this application, "a plurality of" means two or more, unless otherwise expressly and specifically defined. The reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0083] In the description of the embodiments of this application, the technical terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated, or used in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0084] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0085] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A soft-pack battery, characterized in that, include: A battery cell (10) and a housing (20) are provided, the housing (20) housing the battery cell (10), the housing (20) including a first housing (21) and a second housing (22) disposed opposite to each other along a first direction (X), the housing including a body portion and a flange portion, the body portion being disposed opposite to the battery cell, the flange portion being disposed on the outer periphery of the body portion, the flange portions of the first housing (21) and the second housing (22) being sealed together to form a sealing edge, the sealing edge including a first sealing edge (201) extending away from the battery cell (10) along a third direction (Z), the first sealing edge (201) including at least two stacked sealing segments formed by bending; Fastening tape (30), the fastening tape (30) is adhered to the outside of the first sealing edge (201), the fastening tape (30) is used to keep the first sealing edge in a bent state; Wherein, along the second direction (Y), the width of the fastening band (30) is L, and along the first direction, the bonding dimension between the fastening band (30) and the first sealing edge is d, where the units of L and d are mm, and satisfy 85mm. 2 ≤L*d≤400mm 2 The first direction, the second direction, and the third direction are perpendicular to each other.

2. The soft-pack battery according to claim 1, characterized in that, The first sealing edge (201) is bent toward the battery cell (10); the first housing (21) has a first outer surface (211) on the side opposite to the second housing (22) along the first direction (X), the first sealing edge (201) has a first folded segment (201a) and a second folded segment (201b), the first folded segment (201a) is bent toward one side of the first direction (X), the second folded segment (201b) is bent toward the other side of the first direction (X), the first sealing edge (201) has a first folded end (a3), a second folded end (a4) and a tail end (a5), the second folded end is disposed between the first folded end and the tail end; The fastening band (30) has its first end (30a) along its unfolding direction bonded to the first outer surface (211); the fastening band (30) also has a first contact portion (30c) bonded to the first folded end (a3); along the unfolding direction of the fastening band (30), the total length of the first end (30a) from the first contact portion (30c) is C1, in mm, which satisfies 10≤C1≤60.

3. The soft-pack battery according to claim 2, characterized in that, The fastening band (30) also has a second contact portion (30d) that is bonded to the second folded end (a4). Along the unfolding direction of the fastening band (30), the dimension between the first contact portion (30c) and the second contact portion (30d) is C2 in mm, which satisfies 0.67≤C1 / C2≤4.

4. The soft-pack battery according to claim 2, characterized in that, The portion of the fastening band (30) located between the first end (30a) and the first contact portion (30c) is the first fastening section. The bonding dimension between the first fastening section and the first outer surface (211) is C3, which satisfies the condition that 5≤C3≤50 mm.

5. The soft-pack battery according to claim 3, characterized in that, The second housing (22) has a second outer surface (221) on the side opposite to the first housing (21) along the first direction (X); The second end (30b) of the fastening band (30) along its unfolding direction is bonded to the second outer surface (221). The distance between the second end (30b) and the second contact portion (30d) along the unfolding direction of the fastening band (30) is C4, in mm, satisfying 10≤C4≤50.

6. The soft-pack battery according to claim 2, characterized in that, Along the unfolding direction of the first sealing edge (201), the distance between the second folded end (a4) and the tail end (a5) is G, in mm, and satisfies 170 mm. 3 ≤G*(L*d)≤2400mm 3 ; and / or, the size range of G is 2mm to 6mm.

7. The soft-pack battery according to claim 5, characterized in that, The first end (30a) and the second end (30b) are staggered along the third direction (Z) and the stagger distance is H, in mm, satisfying 0.1≤H≤5.

8. The pouch cell battery according to any one of claims 1-7, characterized in that, Along the unfolding direction of the fastening band (30), the fastening band (30) has a first end (30a) and a second end (30b), and the housing (20) has a side opposite to the first sealing edge (201) in a third direction, and the first end (30a) and / or the second end (30b) are bonded to the side.

9. The pouch cell battery according to any one of claims 1-7, characterized in that, The sealing edge further includes a second sealing edge (202) and a third sealing edge (203), the second sealing edge (202) and the third sealing edge (203) are arranged opposite to each other along the second direction (Y), and the first sealing edge (201) connects the second sealing edge (202) and the third sealing edge (203). The battery cell (10) includes a first tab (11) extending from the second sealing edge (202); along the second direction (Y), the shortest interval between the edge of the fastening band (30) near the second sealing edge and the end of the second sealing edge (202) is M1, in mm, satisfying 15≤M1≤80.

10. The soft-pack battery according to claim 9, characterized in that, The battery cell (10) also includes a second tab (12) which extends from the third sealing edge (203).

11. The pouch cell according to any one of claims 1-7, characterized in that, Multiple fastening bands (30) are provided, and the multiple fastening bands (30) are spaced apart along the second direction (Y), with a spacing range of P, in mm, satisfying 50≤P≤200.

12. The soft-pack battery according to claim 11, characterized in that, The sum of the widths of the plurality of fastening bands (30) along the second direction (Y) is L', and the length of the housing (20) along the second direction (Y) is E, in mm, satisfying 0.1≤L' / E≤0.

4.

13. The soft-pack battery according to claim 11, characterized in that, The housing (20) has a midpoint (O) along the second direction (Y), and the distance between the edge of the fastening band (30) closest to the midpoint (O) and the midpoint (O) is M2, in mm, and satisfies 3≤M2≤50.

14. The soft-pack battery according to claim 11, characterized in that, The housing (20) has a midpoint (O) along the second direction (Y), and the fastening band (30) is bonded to the midpoint (O). The battery cell (10) is wrapped with an insulating film, the thickness of which is F1 in mm, and satisfies 0.01≤F1≤0.

1.

15. The pouch cell according to any one of claims 1-7, characterized in that, The fastening band (30) has an adhesive layer and an insulating layer. The adhesive layer is bonded to the first sealing edge (201). The insulating layer is located on the side of the adhesive layer away from the housing. The thickness of the adhesive layer is N1 in mm, which satisfies 0.01≤N1≤0.

15.

16. The pouch cell according to any one of claims 1-7, characterized in that, The housing (20) includes an inner adhesive layer, an intermediate metal layer and an outer protective layer. The intermediate metal layer is disposed between the inner adhesive layer and the outer protective layer. The outer protective layer is located on the outermost side of the intermediate metal layer away from the battery cell (10). The thickness of the intermediate metal layer is F2, and the thickness of the fastening band (30) is N2. The unit of F2 is μm and the unit of N2 is mm. The following conditions are met: 0.1≤F2 / N2≤2; and / or 35≤F2≤60; and / or 0.02≤N2≤6.

17. The pouch cell according to any one of claims 1-7, characterized in that, The length of the first sealing edge (201) along the unfolding direction is B, in mm, and satisfies 8≤B≤20.

18. The soft-pack battery according to claim 17, characterized in that, The first sealing edge (201) includes a first sealing segment, the length of which along the unfolding direction is D, in mm, and satisfies 6≤D≤15.

19. The soft-pack battery according to claim 1, characterized in that, Multiple pouch batteries are provided, and the fastening band (30) is adhered to the first sealing edge (201) of each pouch battery, 60mm. 2 ≤L*d≤300mm 2 .

20. The soft-pack battery according to claim 19, characterized in that, Each of the pouch cells is attached with the fastening band (30), and all of the fastening bands are attached to one pouch cell.

21. The soft-pack battery according to claim 19, characterized in that, One of the fastening bands (30) is used to bond the first sealing edge (201) of at least two pouch cells.

22. An electrical appliance, characterized in that, Includes the pouch cell as described in any one of claims 1-21.

Images