Pouch cell, battery pack, and power consuming device

Abstract

The utility model relates to battery technical field discloses a kind of soft package battery, battery pack and electric device, soft package battery includes shell, electric core, pole lug lead-out part and insulating sealing layer.Shell includes first shell and second shell, shell has flange edge, first shell and second shell all include inner side adhesive layer, intermediate metal layer and outer side protective layer.Pole lug lead-out part is led out from sealing edge to shell outside.Insulating sealing layer is set between pole lug lead-out part and sealing edge.Wherein, the interval distance of the intermediate metal layer of first shell in sealing edge, with the intermediate metal layer of second shell in sealing edge is a.Along the lead-out direction of pole lug lead-out part, the adhesive length between insulating sealing layer and sealing edge is d, satisfy, 0.4mm 2 ≤d*a≤9.5mm 2 The utility model can solve the problem of shell black spot caused by shell electrification and liquid leakage.

Description

Technical Field

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

[0002] With the rapid development of new energy technologies, batteries are being used more and more widely, and they are now being installed in electric vehicles and other fields.

[0003] Currently, pouch batteries are simpler to manufacture and cheaper than prismatic and cylindrical batteries, so they are widely used in the new energy field. However, due to the poor airtightness of the pouch casing, the aluminum layer of the pouch battery casing is often corroded and black spots are produced during battery use, which leads to a decline in the overall performance of the casing and causes safety hazards such as battery fire and explosion. Utility Model Content

[0004] In view of this, the present invention provides a soft-pack battery, a battery pack, and an electrical device to solve the problem of black spots caused by corrosion of the aluminum layer of the soft-pack battery casing, which poses a safety hazard.

[0005] In a first aspect, this utility model provides a soft-pack battery, comprising: a casing having a receiving space, the casing including a first casing and a second casing, both the first casing and the second casing having flange edges, the flange edges of the first casing and the flange edges of the second casing being sealed together to form a sealing edge, both the first casing and the second casing including an inner adhesive layer, an intermediate metal layer and an outer protective layer; a battery cell disposed within the receiving space; a tab lead-out portion electrically connected to the battery cell and extending from the sealing edge to the outside of the casing; and an insulating sealing layer disposed between the tab lead-out portion and the sealing edge; wherein the projections of the first casing, the second casing and the insulating sealing layer overlap to form a first overlapping area, and within the first overlapping area, the distance between the intermediate metal layer of the first casing located at the sealing edge and the intermediate metal layer of the second casing located at the sealing edge along a first direction is a; along the lead-out direction of the tab lead-out portion, the adhesive length between the insulating sealing layer and the sealing edge is d, satisfying 0.4 mm. 2 ≤d*a≤9.5mm 2 The units for d and a are both mm; the lead-out direction of the electrode tab is perpendicular to the first direction.

[0006] Beneficial effects: By controlling the distance between the two intermediate metal layers of the housing sealing edge and the bonding length between the insulating sealing layer and the electrode lead-out part within a suitable range, i.e., 0.4mm, the requirement is met. 2 ≤d*a≤9.5mm 2This ensures a safe distance between the tab lead-out section and the intermediate metal layer, reducing the risk of the intermediate metal layer becoming charged due to their overlap. At the same time, it ensures a safe path to prevent electrolyte leakage, reducing the risk of leakage. This prevents black spots from forming on the intermediate metal layer of the casing, improves the safety of the pouch battery, and avoids excessively low overall space utilization of the pouch battery, which would affect the overall energy density and cycle life of the pouch battery.

[0007] Secondly, this utility model also provides a battery pack, including at least two pouch cells as described in the first aspect embodiment, wherein the at least two pouch cells are arranged along a first direction. This arrangement can save space, improve the space utilization rate of the battery pack, and suppress large-area expansion of the batteries.

[0008] Thirdly, this utility model also provides an electrical device, including the soft-pack battery of the first aspect embodiment.

[0009] Since the electrical device includes the pouch battery of the first aspect embodiment, it has the same beneficial effects as the pouch battery, which will not be described again here. Attached Figure Description

[0010] 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.

[0011] Figure 1 This is a partial top view of the soft-pack battery according to an embodiment of the present invention; Figure 2 This is a cross-sectional view of the soft-pack battery according to an embodiment of the present invention; Figure 3 for Figure 2 Enlarged schematic diagram of the middle section structure; Figure 4 This is a schematic diagram of the structure of the battery cell and the lead-out portion of the electrode according to an embodiment of the present utility model; Figure 5 This is a cross-sectional view of a soft-pack battery according to another embodiment of the present invention; Figure 6 This is a cross-sectional view of a soft-pack battery according to another embodiment of the present utility model; Figure 7 This is a schematic diagram of the battery pack structure according to an embodiment of the present invention.

[0012] Explanation of reference numerals in the attached figures: 10-Housing; 11-First housing; 111-First groove; 112-Rounded corner transition; 12-Second housing; 13-Inner adhesive layer; 14-Intermediate metal layer; 15-Outer protective layer; 101-Sealing edge; 102-Folded connection; 102a-Protruding structure; 102b-Receiving groove; 20-Battery cell; 30-Lead-out part; 31-Electrode tab; 32-Adapter piece; 40-Insulating sealing layer; 41-First insulating sealing layer; 42-Second insulating sealing layer; 200-Panel; X-First direction; Y-Lead-out direction; Z-Second direction. Detailed Implementation

[0013] 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.

[0014] Currently, the casing of pouch batteries is prone to corrosion, resulting in black spots and posing a safety hazard. Research has found that poor sealing at the casing's sealing edges and swelling of the inner adhesive layer (such as the CPP layer) in the electrolyte can cause bulging at the sealing edges, leading to electrolyte leakage. This allows the exposed metal layer at the casing edge to overlap with the electrode leads, forming a lithium-aluminum alloy. This results in black spots on the aluminum foil, reducing casing strength. During charging and discharging, the casing may crack, causing high-temperature gases, liquids, and metal shavings to be ejected from the pouch battery, potentially leading to a fire or explosion. Especially in humid environments (such as during the rainy season), moisture can easily enter the sealing edges during heat sealing, increasing the risk of poor sealing. Furthermore, in humid environments, the electrode leads are more likely to overlap with the aluminum layer edge of the casing, causing the aluminum layer to become charged. The charged aluminum layer reacts chemically with the leaked electrolyte, ultimately forming black spots and creating a safety hazard for pouch batteries. For example, when the aluminum layer is in contact with the negative electrode, the low-potential aluminum layer will form lithium-aluminum alloy black spots on the edge of the aluminum layer under the action of lithium ions and electrons.

[0015] To address this, by controlling the distance between the two intermediate metal layers on the sealing edge of the casing within a suitable range, a safe distance between the tab lead-out portion and the intermediate metal layer can be ensured, reducing the risk of the intermediate metal layer becoming charged due to overlap. At the same time, by controlling the bonding length between the insulating sealing layer and the tab lead-out portion within a suitable range, a safe path can be ensured to prevent electrolyte leakage. Thus, black spots are prevented from forming on the intermediate metal layer of the casing, improving the safety of the soft-pack battery.

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

[0017] According to an embodiment of the present invention, in a first aspect, a pouch battery is provided, comprising a casing 10, a battery cell 20, a tab lead-out portion 30, and an insulating sealing layer 40. The casing 10 includes a first casing 11 and a second casing 12, both having flange edges. The flange edges of the first casing 11 and the second casing 12 are sealed together to form a sealing edge 101. Both the first casing 11 and the second casing 12 include an inner adhesive layer 13, an intermediate metal layer 14, and an outer protective layer 15. The battery cell 20 is disposed within the receiving space of the casing 10. The tab lead-out portion 30 is electrically connected to the battery cell 20 and extends from the sealing edge 101 to the outside of the casing 10. The insulating sealing layer 40 is disposed between the tab lead-out portion 30 and the sealing edge 101. The first housing 11, the second housing 12, and the insulating sealing layer 40 project to form a first overlapping area. Within this first overlapping area, the distance between the intermediate metal layer 14 of the first housing 11 and the intermediate metal layer 14 of the second housing 12 located on the sealing edge 101 along the first direction X is 'a'. Along the lead-out direction Y of the tab lead-out portion 30, the bonding length between the insulating sealing layer 40 and the sealing edge 101 is 'd', satisfying 0.4 mm. 2 ≤d*a≤9.5mm 2 The units for d and a are both mm; the lead-out direction Y of the electrode tab 30 is perpendicular to the first direction X. d*a can be any one of 0.4, 1, 2, 5, 6, 8, 9, 9.5 or any value between two of them. In some embodiments, 0.2mm ≤ a ≤ 1mm. a can be any one of 0.2mm, 0.3mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 1mm or any value between two of them. 2mm ≤ d ≤ 10mm. d can be any one of 2mm, 4mm, 5mm, 7mm, 8mm, 9mm, 10mm or any value between two of them. The value of 'a' includes the thickness of the two insulating sealing layers 40 located between the intermediate metal layer 14 of the first housing 11 and the intermediate metal layer 14 of the second housing 12 in the sealing edge 101, the thickness of the two inner adhesive layers 13, and the thickness of the single electrode lead-out portion 30. The thickness of the single insulating sealing layer 40 is preferably 0.03 mm to 0.18 mm, the thickness of the single inner adhesive layer 13 is preferably 0.05 mm to 0.1 mm, and the thickness of the electrode lead-out portion is preferably 0.2 mm to 0.5 mm.

[0018] Cell 20 can be stacked or wound.

[0019] The battery cell 20 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 pouch cell 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 first housing 11 and the second housing 12 are respectively disposed on the upper and lower surfaces of the battery cell 20. The first housing 11 and the second housing 12 can be connected as a whole or separately, and are sealed together by multiple sealing edges.

[0026] The housing 10 is a soft shell. For example, it can be an aluminum-plastic film.

[0027] The inner adhesive layer 13 can be made of polypropylene (PP) or polyethylene, or other materials resistant to electrolyte corrosion. The middle metal layer 14 can be made of pure aluminum or aluminum alloy, copper, or other metals or alloys used to block moisture and oxygen. The outer protective layer 15 can be made of nylon (ON) or polyethylene terephthalate (PET), and a PET layer can also be added.

[0028] The aluminum-plastic film ensures that the film does not deform during the lithium-ion battery manufacturing process. The primary function of the intermediate metal layer 14 is waterproofing. Lithium batteries are extremely sensitive to moisture, and the packaging film must effectively prevent the intrusion of water vapor. Nylon itself is not waterproof and cannot meet this requirement, while aluminum, after reacting with oxygen in the air, forms a dense oxide film, thereby 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 forming process to meet the requirements of the perforation process.

[0029] The inner adhesive layer 13 can be a PP layer, i.e., a polypropylene layer, which has the property of melting at high temperatures and being adhesive. The thermal sealing process of the battery mainly relies on the PP layer melting and bonding together when the end cap is heated, and then curing and bonding during cooling.

[0030] The flange edges of the first housing 11 and the flange edges of the second housing 12 are bonded or heat-sealed together by their respective inner adhesive layers (heat-sealing layers) to form the sealing edges 101 of the housing 10. The housing 10 also includes a folded connection portion 102, which connects the first housing 11 and the second housing 12. The first housing 11, the second housing 12, and the folded connection portion 102 are an integral structure. The housing 10 has three sealing edges 101, two of which are located along the edge of the housing 10. Figure 2 On opposite sides in the Y direction, another sealing edge and the folded connection 102 are located on opposite sides of the housing 10 in the second direction Z.

[0031] In one example, one of the first housing 11 and the second housing 12 may be provided with a groove, while the other may be a plate-like structure. In another example, both the first housing 11 and the second housing 12 may be provided with grooves, and the edges of the grooves are transitionally connected to the flange edges.

[0032] The tab lead-out portion 30 is used to lead out the internal current of the pouch battery. The tab lead-out portion 30 can be integrally connected to the cell 20, or it can be separately electrically connected to the lead-out end of the cell 20. The electrical connection can be achieved by welding, bonding, snap-fitting, or other methods. For example, the tab of the cell 20 can be directly led out from the sealing edge 101 to form the tab lead-out portion 30, or it can be led out through an adapter piece (such as a tap).

[0033] The first direction X is the direction in which the flange edges of the two housings are stacked. The lead-out direction Y of the tab lead-out section 30 can be the length direction of the pouch battery. The second direction Z can be the width direction of the pouch battery. The first direction X, the second direction Z, and the lead-out direction Y of the tab lead-out section 30 are all perpendicular to each other.

[0034] Since the tab lead-out portion 30 extends from the sealing edge, an insulating sealing layer 40 is used to achieve a better seal between the tab lead-out portion 30 and the sealing edge. At the same time, in order to avoid the risk of short circuit of the battery as a result of the tab lead-out portion 30 overlapping with the intermediate metal layer of the casing 10, and the risk of casing corrosion, the insulating sealing layer 40 ensures the insulation safety between the tab lead-out portion and the sealing edge.

[0035] Insulating sealing layers 40 are respectively disposed on the upper and lower surfaces of the electrode lead-out portion, and the width is greater than or equal to the width of the electrode lead-out portion. The width direction is perpendicular to the first direction X and the lead-out direction Y of the electrode lead-out portion.

[0036] The insulating sealing layer 40 can be made of polypropylene (CPP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene succinate (PBS), polyimide (PI), or other insulating materials.

[0037] The bonding length d between the insulating sealing layer 40 and the sealing edge 101 along the lead-out direction Y of the tab lead-out portion 30 can be obtained by measuring the distance between the end of the insulating sealing layer 40 near the cell 20 along the lead-out direction Y of the tab lead-out portion 30 and the end of the sealing edge 101 away from the cell 20 (outer end). Figure 1 As shown in the figure, the bonding length d is the sealing connection length.

[0038] d*a is too large, greater than 9.5mm 2 It occupies too much space, has low space utilization, and results in low volumetric energy density when pouch batteries are assembled; d*a is too small, less than 0.4mm. 2 The overlap between the electrode lead-out portion 30 and the intermediate metal layer 14, as well as the high risk of electrolyte leakage, leads to black spots on the intermediate metal layer 14 of the casing 10, posing a safety hazard; therefore, 0.4mm 2 ≤d*a≤9.5mm 2 This can reduce the risk of overlap between the tab lead-out part 30 and the intermediate metal layer 14 and electrolyte leakage, prevent black spots from forming on the intermediate metal layer of the casing, improve safety, reduce space occupation, and increase the volumetric energy density when the soft-pack battery is assembled.

[0039] Preferred size: 0.6mm 2 ≤d*a≤8mm 2Within this range, not only is space utilization further improved, but the sealing effect is also guaranteed and leakage is reduced. Furthermore, it avoids the difficulty of shell molding caused by excessively thick shells or the large amount of heat caused by excessively long sealing edges, which affects the insulation effect of the cell separator.

[0040] In some embodiments, refer to Figure 2 and Figure 3 The first housing 11 is provided with a first groove 111, and the edge of the groove 111 is connected to the flange edge of the first housing 11 through a rounded transition portion 112. The distance between the end of the insulating sealing layer 40 near the cell 20 and the rounded transition portion 112 is b1, which satisfies 3mm≤b1≤15mm. b1 can be any one of 3mm, 5mm, 10mm, 13mm, 14mm, and 15mm, or any value between two of them.

[0041] The end of the insulating sealing layer 40 near the cell 20 is bonded to the sealing edge 101. The rounded transition portion 112 has a first end that connects to the sealing edge 101 and a second end that connects to the groove edge of the first groove 111. The distance between the end of the insulating sealing layer 40 near the cell 20 and the first end of the rounded transition portion 112 is b1.

[0042] If b1 is too small (less than 3mm), the rounded transition portion 112 has a certain curvature and relatively weak strength. The end of the insulating sealing layer 40 near the cell 20 is too close to the rounded transition portion 112, which can easily lead to poor sealing between the end of the insulating sealing layer 40 near the cell 20 and the sealing edge 101 of the shell. This increases the risk of electrolyte leakage due to bulging and ultimately increases the probability of black spots forming on the intermediate metal layer of the shell. If b1 is too large (greater than 15mm), it will encroach on the bonding dimension between the insulating sealing layer 40 and the sealing edge 101. That is, if the aforementioned dimension d is too small, the electrolyte leakage path will be shorter, which also leads to a high risk of electrolyte leakage and a greater probability of black spots forming on the intermediate metal layer of the shell. Therefore, 3mm≤b1≤15mm can ensure the sealing effect between the insulating sealing layer 40 and the sealing edge 101 and provide a safe path to prevent electrolyte leakage. This can reduce the risk of overlap between the tab lead-out portion 30 and the intermediate metal layer 14 and electrolyte leakage, prevent black spots forming on the intermediate metal layer of the shell, and improve safety.

[0043] In some embodiments, along the lead-out direction Y of the tab lead-out portion 30, the end of the insulating sealing layer 40 away from the cell 20 extends beyond the sealing edge 101 by a distance b2, satisfying 0.5mm ≤ b2 ≤ 4mm. b2 can be any one of 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, or a value between any two of them.

[0044] If b2 is too small (less than 0.5 mm), creepage and overlap between the tab lead-out portion 30 and the intermediate metal layer 14 of the casing will occur, resulting in a high risk of the intermediate metal layer 14 becoming charged and reacting with the leaked electrolyte, leading to a high risk of black spots on the intermediate metal layer. If b2 is too large (greater than 4 mm), the high temperature during welding of the tab lead-out portion 30 will have a significant impact on the insulating sealing layer 40 (such as weakening the adhesion strength or melting), resulting in a high risk of sealing failure of the insulating sealing layer 40. Therefore, 0.5 mm ≤ b2 ≤ 4 mm can reduce the risk of the intermediate metal layer 14 becoming charged due to overlap between the tab lead-out portion 30 and the intermediate metal layer 14, and also prevent the risk of leakage due to sealing failure of the insulating sealing layer 40, thereby preventing black spots on the intermediate metal layer of the casing and improving safety.

[0045] In some embodiments, the insulating sealing layer 40 includes a first insulating sealing layer 41 located between the flange edge of the first housing 11 and the electrode lead-out portion 30, and a second insulating sealing layer 42 located between the flange edge of the second housing 12 and the electrode lead-out portion 30. Along the lead-out direction Y of the electrode lead-out portion 30, the distance by which the first insulating sealing layer 41 extends beyond the sealing edge 101 is different from the distance by which the second insulating sealing layer 42 extends beyond the sealing edge 101. This configuration avoids the simultaneous failure of the first insulating sealing layer 41 and the second insulating sealing layer 42, further reducing the risk of the intermediate metal layer 14 becoming electrified due to the overlap between the electrode lead-out portion 30 and the intermediate metal layer 14.

[0046] In other embodiments, the distance by which the first insulating sealing layer 41 extends beyond the sealing edge 101 can be the same as the distance by which the second insulating sealing layer 42 extends beyond the sealing edge 101.

[0047] In some embodiments, along the Y-direction of the tab lead-out portion 30, the end of the tab lead-out portion 30 away from the cell 20 extends beyond the end of the insulating sealing layer 40 away from the cell 20 by a distance b3, satisfying 10mm ≤ b3 ≤ 50mm. b3 can be any one of 10mm, 15mm, 20mm, 30mm, 40mm, and 50mm, or a value between any two of them.

[0048] If b3 is too small (less than 10mm), the high temperature during welding of the tab lead 30 can easily weaken the bonding strength of the insulation sealing layer 40 or cause it to melt, resulting in a high risk of leakage due to sealing failure of the insulation sealing layer 40. If b3 is too large (greater than 50mm), it occupies a lot of space, resulting in low space utilization and low volumetric energy density when the pouch battery is assembled. Therefore, 10mm≤b3≤50mm can reduce the risk of leakage due to sealing failure of the insulation sealing layer 40 and also help improve the volumetric energy density when the pouch battery is assembled.

[0049] In some embodiments, along the second direction Z, at least one end of the insulating sealing layer 40 extends beyond the tab lead-out portion 30 by a distance c, satisfying 1.5mm ≤ c ≤ 8mm. c can be any one of 1.5mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, or any value between any two.

[0050] If c is too small, less than 1.5mm, the edge of the tab lead-out portion 30 along the second direction Z overlaps with the intermediate metal layer 14 of the housing, resulting in a high risk of the intermediate metal layer 14 becoming electrified; if c is too large, greater than 8mm, it occupies the bonding size of the sealing edge 101, resulting in a high risk of sealing failure of the sealing edge 101. Therefore, 1.5mm≤c≤8mm can reduce the risk of the intermediate metal layer 14 becoming electrified due to the overlap between the edge of the tab lead-out portion 30 along the second direction Z and the intermediate metal layer 14 of the housing, and can also reduce the risk of sealing failure of the sealing edge 101.

[0051] In some embodiments, along the second direction Z, the distance between the edge of the insulating sealing layer 40 and the inner wall of the housing 10 is m, satisfying 8mm ≤ m ≤ 40mm. m can be any one of 8mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, or any combination thereof.

[0052] If m is too small (less than 8 mm), the distance between the edge of the insulating sealing layer 40 and the inner wall of the housing 10 is too close, occupying the sealing dimension of the sealing edge 101, resulting in a high risk of leakage due to sealing failure of the sealing edge 101. If m is too large (greater than 40 mm), it encroaches on the edge of the insulating sealing layer 40 beyond the dimension c of the tab lead-out portion 30, causing the tab lead-out portion 30 to overlap with the intermediate metal layer 14 of the housing, resulting in a high risk of the intermediate metal layer 14 becoming charged. Therefore, 8 mm ≤ m ≤ 40 mm can reduce the risk of the intermediate metal layer 14 becoming charged due to the overlap between the edge of the tab lead-out portion 30 along the second direction Z and the intermediate metal layer 14 of the housing, and can also reduce the risk of sealing failure of the sealing edge 101.

[0053] In some embodiments, the insulating sealing layer 40 includes a first insulating sealing layer 41 located between the flange edge of the first housing 11 and the electrode lead-out portion 30, and a second insulating sealing layer 42 located between the flange edge of the second housing 12 and the electrode lead-out portion 30. Along the first direction X, the thickness of the first insulating sealing layer 41 is t1, and the thickness of the intermediate metal layer 14 of the first housing 11 located at the sealing edge 101 is t2, satisfying 0.3 ≤ t1 / t2 ≤ 2. t1 / t2 can be any one of 0.3, 0.5, 1, 1.3, 1.6, 2, or a value between any two of these.

[0054] If t1 / t2 is too large or too small, the thickness of the first insulating sealing layer 41 will differ significantly from the thickness of the intermediate metal layer 14. This can easily lead to poor sealing between the edge of the first insulating sealing layer 41 along the second direction Z and the sealing edge 101, resulting in a high risk of electrolyte leakage. Therefore, 0.3 ≤ t1 / t2 ≤ 2 ensures that the thickness difference between the first insulating sealing layer 41 and the intermediate metal layer 14 is small, guaranteeing a good seal between the edge of the first insulating sealing layer 41 along the second direction Z and the sealing edge 101, thus reducing the risk of electrolyte leakage.

[0055] In some embodiments, the thickness of the first insulating sealing layer 41 ranges from 30 μm to 200 μm; the thickness of the second insulating sealing layer 42 ranges from 30 μm to 200 μm. The thickness of the first insulating sealing layer 41 can be any one of 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, and 200 μm, or a value between any two of these. The thickness of the second insulating sealing layer 42 can be any one of 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, and 200 μm, or a value between any two of these.

[0056] If the thickness of the first insulating sealing layer 41 and / or the thickness of the second insulating sealing layer 42 is too thick, exceeding 200 μm, the adhesion curvature between the edge of the first insulating sealing layer 41 along the second direction Z and the sealing edge 101 is large, resulting in a high risk of sealing failure. If the thickness of the first insulating sealing layer 41 and / or the thickness of the second insulating sealing layer 42 is too thin, the allowance during hot melting will be insufficient, which will also lead to a high risk of sealing failure. Therefore, the thickness of the first insulating sealing layer 41 and / or the thickness of the second insulating sealing layer 42 should be in the range of 30 μm to 200 μm to reduce the risk of sealing failure between the insulating sealing layer 40 and the sealing edge 101.

[0057] In some embodiments, the thickness of the first insulating sealing layer 41 and the thickness of the second insulating sealing layer 42 are equal. This ensures better sealing consistency between the first insulating sealing layer 41 and the sealing edge 101, and between the second insulating sealing layer 42 and the sealing edge 101, further reducing the risk of sealing failure between the insulating sealing layer 40 and the sealing edge 101.

[0058] In some embodiments, the thickness t2 of the intermediate metal layer 14 of the first housing 11 located at the sealing edge 101 satisfies 0.03mm ≤ t2 ≤ 0.1mm. t2 can be any one of 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, or a value between any two of them.

[0059] If t2 is too small, less than 0.03 mm, the shell strength will be insufficient, and cracking will lead to a high risk of leakage. If t2 is too large, greater than 0.1 mm, the adhesion between the edge of the first insulating sealing layer 41 along the second direction Z and the sealing edge 101 will be poor, resulting in poor sealing and a high risk of leakage. Therefore, 0.03 mm ≤ t2 ≤ 0.1 mm can improve both the shell strength and the sealing effect, thereby reducing the risk of leakage.

[0060] In some embodiments, the thickness h of the electrode lead-out portion 30 ranges from 0.1 mm to 0.8 mm. h can be any one of 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, and 0.8 mm, or a value between any two of them.

[0061] If h is too small, less than 0.1 mm, the strength of the tab lead-out portion 30 is insufficient, and the risk of breakage during welding or bending is high; if h is too large, greater than 0.8 mm, the adhesion between the edge of the first insulating sealing layer 41 along the second direction Z and the sealing edge 101 is poor, resulting in poor sealing and a high risk of leakage. The thickness h of the tab lead-out portion 30 is in the range of 0.1 mm to 0.8 mm, which can reduce the risk of breakage of the tab lead-out portion 30 and improve the sealing effect, thereby reducing the risk of leakage.

[0062] In some embodiments, two electrode leads 30 are provided, and the two electrode leads 30 are located on the same side of the housing 10 along the lead-out direction Y. An insulating sealing layer 40 is provided between each of the two electrode leads 30 and the sealing edge 101. Along the second direction Z, the two insulating sealing layers 40 are spaced apart, and the spacing between them ranges from 10mm to 50mm. It can be any one of 10mm, 20mm, 30mm, 40mm, and 50mm, or any value between two of them.

[0063] Because the two tab leads 30 located on the same side of the housing 10 generate a large amount of heat, they are more prone to sealing failure of the insulating sealing layer 40. Therefore, a larger distance is needed between the two insulating sealing layers 40 to ensure sufficient heat fusion space between them. If this distance is too small (less than 10mm), the heat fusion space between the two insulating sealing layers 40 is insufficient, and the risk of sealing failure between the insulating sealing layer 40 and the sealing edge 101 is high. If this distance is too large (greater than 50mm), the distance from the edge of each insulating sealing layer 40 along the second direction Z to the corresponding inner wall of the housing (…) Figure 1 If the distance between the two insulating sealing layers 40 (m) is too small, the risk of sealing failure between the sealing edge 101 and the edge of the insulating sealing layer 40 along the second direction Z is high. Therefore, the distance between the two insulating sealing layers 40 is in the range of 10mm to 50mm, which can ensure the sealing effect between each insulating sealing layer 40 and the sealing edge 101 and reduce the risk of leakage.

[0064] In some embodiments, refer to Figure 4 The electrode lead-out portion 30 includes an adapter piece 32 and an electrode 31. The electrode 31 is connected to the electrode plate of the battery cell 20. The adapter piece 32 extends from the sealing edge 101 to the outside of the housing 10. An insulating sealing layer 40 is disposed between the adapter piece 32 and the sealing edge 101. The adapter piece 32 and the electrode 31 are welded to form a solder mark F. The insulating sealing layer 40 and the solder mark F are spaced apart, with a spacing e ranging from 0.5mm to 5mm. e can be any one of 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, and 5mm, or any value between any two.

[0065] If e is too small (less than 0.5 mm), the high temperature during welding of the adapter 32 and the tab 31 can easily cause the insulation sealing layer 40 to melt and fail. If e is too large (greater than 5 mm), it will result in a large waste of internal space between the electrode end of the cell 20 and the casing, leading to a low volumetric energy density of the soft-pack battery. Therefore, the distance e between the insulation sealing layer 40 and the solder mark F should be between 0.5 mm and 5 mm. This can prevent the insulation sealing layer 40 from melting and failing due to the high temperature during welding of the adapter 32 and the tab 31, and can also help improve the volumetric energy density of the soft-pack battery.

[0066] In some embodiments, refer to Figure 5 A protruding structure 102a is provided on the side of the housing 10 adjacent to the electrode lead-out portion 30. The protruding structure 102a protrudes toward the side away from the battery cell 20, and the side of the protruding structure close to the battery cell 20 has a receiving groove 102b. The side of the housing 10 adjacent to the electrode lead-out portion 30 can be a folding connection portion 102 of the housing 10.

[0067] The receiving tank 102b of the protruding structure 102a can hold a portion of the electrolyte and disperse a portion of the electrolyte, reducing the risk of electrolyte accumulation at the electrode lead-out part 30, which would lead to increased gas production and break through the insulating sealing layer 40, causing leakage.

[0068] In some embodiments, refer to Figure 6 There are two electrode lead-out portions 30, located on opposite sides of the housing 10 along the lead-out direction Y, 0.4mm apart. 2 ≤d*a≤8mm 2 One of the two electrode leads 30 can be a positive electrode lead and the other a negative electrode lead.

[0069] The positive and negative tabs are respectively located on opposite sides of the housing 10 to avoid concentrated heat generation from the tabs, which would affect the sealing effect of the sealing edge and cause the electrolyte to come into contact with the aluminum shell through the sealing edge.

[0070] In some embodiments, refer to Figure 2The battery cell 20 includes multiple layers of electrodes, which are stacked along a first direction X, and the first direction X is perpendicular to the lead-out direction Y of the electrode lead-out portion.

[0071] The battery cells 20 are stacked along the first direction X. During cycling, they expand more along the first direction X, passing through 0.4mm. 2 ≤d*a≤9.5mm 2 This ensures a safe distance between the tab lead-out section and the intermediate metal layer, as well as a safe path to prevent electrolyte leakage and black spots from forming on the intermediate metal layer of the casing.

[0072] This invention also provides a battery pack comprising at least two pouch cells, arranged along a first direction X. This arrangement saves space, improves the space utilization of the battery pack, and suppresses large-area expansion of the batteries.

[0073] Multiple pouch batteries can be secured together using fasteners such as cable ties, or they can be secured using plate 200 (see reference). Figure 7 The plate 200 may include components such as end plates and side plates. Multiple pouch cells in the battery pack can be connected in series and / or in parallel. Multiple battery packs connected together can form a battery pack.

[0074] This utility model also provides an electrical device, including a pouch battery as described in any of the above embodiments.

[0075] Electrical devices can be, but are not limited to, 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.

[0076] Electrical devices can also include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, 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., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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: The housing (10) has a receiving space. The housing (10) includes a first housing (11) and a second housing (12). Both the first housing (11) and the second housing (12) have flange edges. The flange edges of the first housing (11) and the flange edges of the second housing (12) are sealed together to form a sealing edge (101). Both the first housing (11) and the second housing (12) include an inner adhesive layer (13), an intermediate metal layer (14), and an outer protective layer (15). The battery cell (20) is disposed within the accommodating space; The electrode lead-out portion (30) is electrically connected to the battery cell (20) and extends from the sealing edge (101) to the outside of the housing (10); An insulating sealing layer (40) is disposed between the electrode lead-out portion (30) and the sealing edge (101); The first housing, the second housing, and the insulating sealing layer project to form a first overlapping area. Within this first overlapping area, the distance between the intermediate metal layer (14) of the first housing (11) on the sealing edge (101) and the intermediate metal layer (14) of the second housing (12) on the sealing edge (101) along the first direction (X) is a. Along the lead-out direction (Y) of the tab lead-out portion (30), the bonding length between the insulating sealing layer (40) and the sealing edge (101) is d, satisfying 0.4 mm. 2 ≤d*a≤9.5mm 2 The units of a and d are both mm; the lead-out direction (Y) of the electrode lead-out part (30) is perpendicular to the first direction (X).

2. The soft-pack battery according to claim 1, characterized in that, The first housing (11) is provided with a first groove (111), and the groove edge of the first groove (111) is connected to the flange edge of the first housing (11) through a rounded transition part (112). Along the lead-out direction (Y) of the tab lead-out portion (30), the distance between the insulating sealing layer (40) near the end of the cell (20) and the rounded corner transition portion is b1, which satisfies 3mm≤b1≤15mm.

3. The soft-pack battery according to claim 1, characterized in that, Along the lead-out direction (Y) of the tab lead-out portion (30), the end of the insulating sealing layer (40) away from the cell (20) extends beyond the sealing edge (101) by a distance of b2, satisfying 0.5mm≤b2≤4mm.

4. The soft-pack battery according to claim 3, characterized in that, The insulating sealing layer (40) includes a first insulating sealing layer (41) located between the flange edge of the first housing (11) and the electrode lead-out portion (30) and a second insulating sealing layer (42) located between the flange edge of the second housing (12) and the electrode lead-out portion (30). Along the lead-out direction (Y) of the electrode lead-out portion (30), the distance by which the first insulating sealing layer (41) extends beyond the sealing edge (101) is different from the distance by which the second insulating sealing layer (42) extends beyond the sealing edge (101).

5. The soft-pack battery according to claim 1, characterized in that, Along the lead-out direction (Y) of the tab lead-out portion (30), the end of the tab lead-out portion (30) away from the battery cell (20) extends beyond the end of the insulating sealing layer (40) away from the battery cell (20) by a distance of b3, satisfying 10mm≤b3≤50mm.

6. The soft-pack battery according to claim 1, characterized in that, Along the second direction (Z), at least one edge of the insulating sealing layer (40) extends beyond the tab lead-out portion (30) by a distance c, satisfying 1.5mm≤c≤8mm; the first direction (X), the second direction (Z), and the lead-out direction (Y) of the tab lead-out portion (30) are perpendicular to each other.

7. The soft-pack battery according to claim 1, characterized in that, Along the second direction (Z), the distance between the edge of the insulating sealing layer (40) and the inner wall of the housing (10) is m, which satisfies 8mm≤m≤40mm; the first direction (X), the second direction (Z) and the lead-out direction (Y) of the tab lead-out part (30) are perpendicular to each other.

8. The soft-pack battery according to claim 1, characterized in that, The insulating sealing layer (40) includes a first insulating sealing layer (41) located between the flange edge of the first housing (11) and the electrode lead-out portion (30) and a second insulating sealing layer (42) located between the flange edge of the second housing (12) and the electrode lead-out portion (30). Along the first direction (X), the thickness of the first insulating sealing layer (41) is t1, and the thickness of the intermediate metal layer (14) of the first housing (11) located at the sealing edge (101) is t2, satisfying 0.3≤t1 / t2≤6.

9. The soft-pack battery according to claim 8, characterized in that, The thickness of the first insulating sealing layer (41) ranges from 30 μm to 200 μm; and / or the thickness of the second insulating sealing layer (42) ranges from 30 μm to 200 μm.

10. The soft-pack battery according to claim 9, characterized in that, The thickness of the first insulating sealing layer (41) is equal to the thickness of the second insulating sealing layer.

11. The soft-pack battery according to claim 8, characterized in that, The thickness t2 of the intermediate metal layer (14) of the first housing (11) located on the sealing edge (101) satisfies 0.03mm≤t2≤0.1mm.

12. The pouch cell according to any one of claims 1-11, characterized in that, The thickness of the tab lead-out portion (30) ranges from 0.1 mm to 0.8 mm.

13. The pouch cell according to any one of claims 1-11, characterized in that, Two electrode leads (30) are provided. The two electrode leads (30) are located on the same side of the housing (10) along the lead-out direction (Y). An insulating sealing layer (40) is provided between the two electrode leads (30) and the sealing edge (101). Along the second direction (Z), the two insulating sealing layers (40) are spaced apart with a spacing range of 10mm to 50mm. The first direction (X), the second direction (Z) and the lead-out direction (Y) of the electrode leads (30) are perpendicular to each other.

14. The pouch cell according to any one of claims 1-11, characterized in that, The electrode lead-out part (30) includes an adapter piece and an electrode piece. The electrode piece is connected to the electrode plate of the battery cell (20). The adapter piece extends from the sealing edge (101) to the outside of the housing (10). The insulating sealing layer (40) is disposed between the adapter piece and the sealing edge (101). The adapter piece is welded to the electrode piece to form a solder mark (F). The insulating sealing layer (40) and the solder mark (F) are spaced apart, with a spacing range of 0.5mm to 5mm.

15. The pouch cell according to any one of claims 1-11, characterized in that, 0.2mm≤a≤1mm; and / or, 2mm≤d≤10mm.

16. The pouch cell according to any one of claims 1-11, characterized in that, The housing (10) has a protruding structure on the side adjacent to the tab lead-out portion (30). The protruding structure protrudes toward the side away from the battery cell (20), and the side of the protruding structure close to the battery cell (20) has a receiving groove.

17. The pouch cell according to any one of claims 1-11, characterized in that, Two electrode leads (30) are provided, and the two electrode leads (30) are located on opposite sides of the housing (10) along the lead-out direction (Y), 0.4mm apart. 2 ≤d*a≤8mm 2 .

18. The pouch cell according to any one of claims 1-11, characterized in that, The battery cell includes multiple layers of electrodes, which are stacked along the first direction (X).

19. The pouch cell according to any one of claims 1-11, characterized in that, 0.6mm 2 ≤d*a≤8mm 2 。 20. A battery pack, characterized in that, It includes at least two pouch cells as described above, with the at least two pouch cells arranged along a first direction.

21. An electrical appliance, characterized in that, include: The pouch cell battery according to any one of claims 1-19.

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