Insulating part, battery cell, manufacturing method of battery cell and electric equipment

Abstract

The invention discloses an insulating part, a battery cell, a manufacturing method of the insulating part and electric equipment, the insulating part is configured to be heated to 190 DEG C and molten for 10 minutes, and the viscosity of the molten insulating part is 1000 cps to 5000 cps. The viscosity is too small, an insulating part is not easy to form, the viscosity is too large, the fluidity of an insulating material is poor, the insulating material is not easy to flow out of a glue injection part, and the production difficulty is large. The viscosity of the molten insulating part is limited to be 1000 cps to 5000 cps, so that forming of the insulating part is facilitated, and production is facilitated.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to an insulating component, a battery cell, a manufacturing method thereof, and an electrical device. Background Art

[0002] In secondary batteries, internal short circuits are the most common source of safety issues such as fires, and the mode that generates the most heat and is most likely to cause fire and explosion is when the positive electrode foil contacts the negative electrode. Currently, in order to reduce the risk of short circuits in battery cells, insulating parts are usually pasted inside the battery cells. Summary of the invention

[0003] In view of this, it is necessary to provide an insulating part, a battery cell, a manufacturing method thereof, and an electrical device, which are conducive to the molding of the insulating part and facilitate production.

[0004] An embodiment of the present application provides an insulating part, which is configured to be heated to 190°C and kept melted for 10 minutes, and the viscosity of the insulating part after melting is 1000cps to 5000cps. If the viscosity is too low, the insulating part is not easy to mold, and if the viscosity is too high, the fluidity of the insulating material is poor and it is not easy to flow out of the injection part, which makes production difficult. The present application limits the viscosity of the insulating part after melting to 1000cps to 5000cps, which is conducive to the molding of the insulating part and facilitates production.

[0005] In one or more optional embodiments above, the tensile strength P of the insulating member is P≥3MPa. When the insulating member is in use, it is not easy to be deformed or broken, which is beneficial to insulation.

[0006] In one or more of the above optional embodiments, the material of the insulating part includes one or more of modified polypropylene, modified polyethylene, modified ethylene-based elastomer, modified propylene-based elastomer, modified styrene-based elastomer, modified ionomer resin, modified polyvinylidene fluoride, modified vinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate and modified polyethylene glycol, which is beneficial to improving the bonding strength of the insulating part.

[0007] In one or more of the above optional embodiments, the modified material includes one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride and epoxy groups. The modified material has the ability to bond with metal, which is beneficial to improving the bonding strength of the insulating part.

[0008] In one or more optional embodiments above, the insulating member includes an inorganic filler, and the inorganic filler includes one or more of boehmite, silica, calcium carbonate, talc, wollastonite, quartz powder, alumina, mica powder, titanium dioxide and glass fiber.

[0009] In one or more of the above optional embodiments, the mass of the inorganic filler accounts for 5% to 10% of the total mass of the insulating member. The hardness of the insulating member is increased to improve the situation where the insulating member is easily deformed or missing during the pasting process, and to reduce the situation where the insulating member is too hard, resulting in the insulating member being easy to crack. For example, when the insulating member is pasted into the battery cell and soaked in electrolyte, if the insulating member is too hard, it is easy to crack.

[0010] In one or more optional embodiments above, the thickness d of the insulating member is 10 μm ≤ d ≤ 200 μm. In this way, the insulating performance of the insulating member can be improved and the space occupied by the insulating member can be reduced.

[0011] In one or more of the above optional embodiments, the thickness d of the insulating member is 10 μm≤d≤50 μm, which can improve the insulation performance of the insulating member and further reduce the space occupied by the insulating member.

[0012] In one or more of the above optional embodiments, the melting point T of the insulating member is 100° C. ≤ T ≤ 200° C. During use, the insulating member is not easy to melt or shrink, which is conducive to playing an insulating role.

[0013] The embodiment of the present application provides a battery cell, comprising a first pole piece and an insulating member in any one of the above embodiments. The first pole piece comprises a current collector and an active material layer, the current collector comprises a first section and a second section arranged along a first direction, the active material layer is arranged on the surface of the first section, the insulating member is arranged at least in the second section, the first direction is the length direction or width direction of the first pole piece, the second section is insulated and protected, and the risk of burrs piercing the isolation membrane and causing the second section to short-circuit with the second pole piece is reduced.

[0014] In one or more optional embodiments above, the battery cell includes an electrical connector, the current collector includes a third section, the third section is connected to the second section, the electrical connector is arranged in the third section, and the insulating member covers part of the electrical connector to insulate and protect the electrical connector.

[0015] In one or more optional embodiments above, along the first direction, the width d1 of the insulation member overlapping the active material layer is 0.1 mm ≤ d1 ≤ 2 mm, which is beneficial to avoid improving insulation reliability.

[0016] In one or more of the above optional embodiments, the electrical connector is welded to connect the third section to form a welding area, and the insulating member covers the welding area to insulate and protect the welding area.

[0017] In one or more optional embodiments above, the battery cell includes at least two insulating members, and along the second direction, the electrical connector is located between the two insulating members. The second direction is the thickness direction of the battery cell. Along the first direction, the insulating member includes a first region, and along the second direction, the first region extends out of the first direction to a third section. The first region includes a first sub-region, and along the second direction, the projection of the first sub-region is separated from the projection of the electrical connector. Along the second direction, the first sub-regions of two adjacent insulating members are connected. By connecting the two first sub-regions, the two sides of the electrical connector along the third direction are covered, thereby reducing the risk of burrs on the electrical connector piercing the isolation membrane.

[0018] In one or more of the above optional embodiments, along the second direction, at least a portion of the second section is disposed between two insulating members.

[0019] In one or more of the above optional embodiments, the bonding force F between the insulating member and the electrical connector, F≥0.08N / mm, is beneficial to reducing the risk of the insulating member detaching and causing a short circuit between the first pole piece and the second pole piece.

[0020] In one or more optional embodiments above, the current collector includes a polymer layer and two metal layers, the polymer layer is located between the two metal layers, and the active material layer is disposed on the surface of the metal layer.

[0021] In one or more optional embodiments above, the first pole piece includes a primer layer, which is disposed in the second section to reduce the risk of burrs piercing the isolation membrane and causing the second section to short-circuit with the second pole piece. Along the second direction, the insulating member connects the primer layer and the electrical connector to further reduce the risk of burrs piercing the isolation membrane.

[0022] In one or more optional embodiments above, along the first direction, there is a gap d2 between the insulating member and the active material layer, 0mm≤d2≤0.7mm. The insulating member and the active material layer do not overlap, which can avoid increasing the thickness of the battery cell. If the gap exceeds 0.7mm, the first pole piece, the bottom coating, the electrical connector and the insulating member may be folded due to the large gap, causing safety risks.

[0023] In one or more of the above optional embodiments, after the first pole piece bonded with the insulating component is immersed in 85°C DMC solution for 24 hours, the bonding force F between the insulating component and the electrical connector is ≥0.06N / mm, which is beneficial to reduce the risk of short circuit between the first pole piece and the second pole piece due to detachment of the insulating component due to immersion in the electrolyte during the use of the battery cell.

[0024] In one or more optional embodiments above, the insulating member is attached to the second section. Attaching to means that the insulating member is attached to the second section by means of pasting.

[0025] An embodiment of the present application provides a method for manufacturing a battery cell of any one of the above embodiments, wherein an insulating member is disposed on a carrier, comprising the following steps: forming the first pole piece by coating and cold pressing; bonding the insulating member to the second section; and separating the carrier and the insulating member.

[0026] In a method for manufacturing a battery cell of the above embodiment, between step 1 and step 2, the method further includes welding two electrical connectors on both sides of the third section to form a welding area, and the insulating member covers the welding area.

[0027] An embodiment of the present application provides an electrical device, comprising the battery cell in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of the structure of a carrier and an insulating member in some embodiments of the present application is shown.

[0029] Figure 2 A schematic cross-sectional view of a carrier and an insulating member in some embodiments of the present application is shown.

[0030] Figure 3 The schematic diagrams of the structures of the carrier and the glue injection parts in other embodiments of the present application are shown.

[0031] Figure 4 A schematic flow chart of a method for manufacturing an insulating member in some embodiments of the present application is shown.

[0032] Figure 5 A schematic diagram of the structure of a battery cell in some embodiments of the present application is shown.

[0033] Figure 6 A partial cross-sectional schematic diagram of a battery cell in some embodiments of the present application is shown.

[0034] Figure 7 Partial cross-sectional schematic diagrams of battery cells in other embodiments of the present application are shown.

[0035] Figure 8 Partial cross-sectional schematic diagrams of battery cells in some other embodiments of the present application are shown.

[0036] Fig. 9 A partial structural schematic diagram of a battery cell in some embodiments of the present application is shown.

[0037] Fig.10 A schematic flow chart of a method for manufacturing a battery cell in some embodiments of the present application is shown.

[0038] Fig.11 A schematic diagram of the structure of electrical equipment in some embodiments of the present application is shown.

[0039] Description of main component symbols:

[0040] Insulation 100

[0041] First area 110

[0042] The first sub-region 110a

[0043] Carrier 200

[0044] The first composite layer 210

[0045] Opening 201

[0046] The first release layer 211

[0047] First Base 212

[0048] First adhesive layer 213

[0049] The second composite layer 220

[0050] Second release layer 221

[0051] Second base 222

[0052] Battery Cell 300

[0053] Battery shell 301

[0054] Electrode terminal 302

[0055] The first pole piece 310

[0056] Current collector 311

[0057] Active material layer 312

[0058] Base coating 313

[0059] First section 311a

[0060] Second section 311b

[0061] The third section 311c

[0062] Electrical connector 320

[0063] Welding area 320a

[0064] Welding stamp 3201

[0065] Injection parts 1

[0066] First direction X

[0067] Second direction Y

[0068] The following specific embodiments will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0069] The following specific embodiments are exemplary and non-limiting, and are intended to provide a basic understanding of the present application, and are not intended to identify the key or decisive elements of the present application or to limit the scope of protection. As long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way.

[0070] When a component is considered to be “provided on” another component, it can be directly provided on the other component or there may be a component in between. When a component is considered to be “connected to” another component, it can be directly connected to the other component or there may be a component in between.

[0071] It can be understood that the term "perpendicular" is used to describe an ideal state between two components. In actual production or use, there may be a state that is approximately perpendicular or equal to each other between the two components. For example, in combination with numerical descriptions, perpendicularity can refer to the angle between two straight lines being between 90°±10°, perpendicularity can also refer to the dihedral angle between two planes being between 90°±10°, and perpendicularity can also refer to the angle between a straight line and a plane being between 90°±10°. The two components described as "perpendicular" may not be absolute straight lines or planes, but may be roughly straight lines or planes. From a macroscopic perspective, a component can be considered a "straight line" or a "plane" if the overall extension direction is a straight line or a plane.

[0072] Unless otherwise defined, when the term "plurality" is used to describe the number of components, it specifically means that the components are two or more.

[0073] Some embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0074] See also Figure 1 and Figure 3 The first embodiment of the present application provides an insulating part 100, which is configured to be heated to 190°C and kept melted for 10 minutes. The viscosity of the insulating part 100 after melting is 1000cps to 5000cps. If the viscosity is too low, the insulating part 100 is not easy to mold. If the viscosity is too high, the fluidity of the insulating material is poor and it is not easy to flow out of the injection part 1, which makes production difficult. The present application limits the viscosity of the insulating part 100 after melting to 1000cps to 5000cps, which is conducive to the molding of the insulating part 100 and facilitates production.

[0075] Optionally, the viscosity of the insulating member 100 after melting may be 1000cps, 1100cps, 1200cps, 1300cps, 1400cps, 1500cps, 1600cps, 1700cps, 1800cps, 1900cps, 2000cps, 2100cps, 2200cps, 2300cps, 2400cps, 2500cps, 2600cps, 2700cps, 2800cps, 2900cps, 3000cps, 3100cps, 3200cps, 3300cps, 3400cps, 3500cps, 3600cps, 3700cps, 3800cps, 3900cps, 4000cps, 4100cps, 4200cps, 4300cps, 4400cps, 4500cps, 4600cps, 4700cps, 4800cps, 4900cps, 5000cps, 5100cps, 5200cps, 5300cps, 5400cps, 5500cps, 5600cps, 5700cps, 5800cps, 5900cps, 600cps, 6100cps, 6200cps, 6300cps, 6400cps The content of the present invention is in the range of any one of 3000cps, 3100cps, 3200cps, 3300cps, 3400cps, 3500cps, 3600cps, 3700cps, 3800cps, 3900cps, 4000cps, 4100cps, 4200cps, 4300cps, 4400cps, 4500cps, 4600cps, 4700cps, 4800cps, 4900cps and 5000cps, or a range consisting of any two of them.

[0076] In some embodiments, the tensile strength P of the insulating member 100 is P≥3Mpa. Thus, the insulating member 100 is not easily deformed or broken during use, which is beneficial for insulation.

[0077] In some embodiments, the insulating material includes one or more of modified polypropylene, modified polyethylene, modified ethylene-based elastomer, modified propylene-based elastomer, modified styrene-based elastomer, modified ionomer resin, modified polyvinylidene fluoride, modified vinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate and modified polyethylene glycol, which is beneficial to improving the bonding strength of the insulating member 100.

[0078] In some embodiments, the modified material includes one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride and epoxy groups. The modified material has the ability to bond with metal, which is beneficial to improving the bonding strength of the insulating member 100 .

[0079] In some embodiments, the insulating material includes an inorganic filler, and the inorganic filler includes one or more of boehmite, silica, calcium carbonate, talc, wollastonite, quartz powder, alumina, mica powder, titanium dioxide, and glass fiber.

[0080] In some embodiments, the mass of the inorganic filler accounts for 5% to 10% based on the total mass of the insulating member 100. The hardness of the insulating member 100 is increased to improve the situation that the insulating member 100 is easily deformed or missing during the pasting process, and the situation that the insulating member 100 is too hard, resulting in the insulating member 100 being easy to crack, is reduced. For example, when the insulating member 100 is pasted in the battery cell and soaked in electrolyte, if the insulating member 100 is too hard, it is easy to crack.

[0081] Optionally, the mass proportion of the inorganic filler may be in the range of any one of 5%, 6%, 7%, 8%, 9%, 10%, or any two of them.

[0082] In some embodiments, the thickness d of the insulating member 100 is 10 μm ≤ d ≤ 200 μm. In this way, the insulating performance of the insulating member 100 can be improved and the space occupied by the insulating member 100 can be reduced.

[0083] Optionally, d can be any one of 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, or a range consisting of any two of them.

[0084] In some embodiments, 10 μm≤d≤50 μm, which can improve the insulation performance of the insulating member 100 and further reduce the space occupied by the insulating member 100 .

[0085] In some embodiments, the width h of the insulating member 100 is 1.5 mm ≤ h ≤ 10 mm.

[0086] Optionally, h can be any one of 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4.mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9.0mm, 9.5mm, and 10mm, or a range consisting of any two of them.

[0087] In some embodiments, the length l of the insulating member 100 is 3 mm ≤ h ≤ 20 mm.

[0088] Optionally, l can be any one of 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, and 20mm, or a range consisting of any two of them.

[0089] In some embodiments, the melting point T of the insulating member 100 is 100° C. ≤ T ≤ 200° C. During use, the insulating member 100 is not easy to melt or shrink, which is conducive to playing an insulating role. For example, the insulating member 100 does not shrink during the use of the battery cell, reducing the occurrence of short circuits.

[0090] Alternatively, T may be in the range of any two of 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, and 200°C.

[0091] See also Figure 1 and Figure 4 An embodiment of the present application provides a method for manufacturing the insulating member 100, comprising the following steps:

[0092] Step 1: heating the insulating material until it is melted, and injecting the melted insulating material into the opening 201 of the carrier 200;

[0093] Step 2: After the insulating material is cooled, the insulating member 100 is formed.

[0094] In some embodiments, in the above step 1, the insulating material is heated to 190° C. and kept melted for 10 minutes.

[0095] See also Figure 3 In some embodiments, in step 1 above, the insulating material is injected into the opening 201 of the carrier 200 through the injection molding 1 .

[0096] In some embodiments, step 1 specifically includes heating the insulating material to 190° C., and then using air pressure and a gear pump to allow the insulating material to flow out through a flow channel and finally through a glue outlet, and coating the insulating material on the surface of a carrier 200. The rolled-up carrier 200 is pulled by an apparatus so that the carrier 200 passes through a glue injection part 1, and the glue injection part 1 abuts against the surface of the carrier 200. When the opening 201 passes through the glue injection part 1, the glue injection part 1 scrapes the insulating material into the opening 201.

[0097] In some embodiments, step 2 specifically includes cooling by air and then solidifying to form the insulating member 100 .

[0098] In some embodiments, the thickness of the injection piece 1 is greater than the width of the opening 201 , which facilitates the insulating material to be scraped into the opening 201 .

[0099] See also Figure 2 The carrier 200 includes a first composite layer 210 and a second composite layer 220 arranged along a first direction X, and the first composite layer 210 is connected to the second composite layer 220. The first direction X is a thickness direction of the carrier 200.

[0100] In some embodiments, the first composite layer 210 is provided with an opening 201 , the opening 201 penetrates through the first composite layer 210 , and the opening 201 is configured to receive an insulating material.

[0101] In some embodiments, the first composite layer 210 includes a first release layer 211 . Along the first direction X, the first release layer 211 is located at the outermost side of the first composite layer 210 and faces away from the second composite layer 220 .

[0102] In some embodiments, the second composite layer 220 includes a second release layer 221 . The second release layer 221 is connected to the first composite layer 210 , and the second release layer 221 is exposed in the opening 201 .

[0103] The first release layer 211 is used to reduce the adhesion between the insulating material in the injection part 1 and the carrier 200, thereby reducing the residual insulating material around the opening 201. The second release layer 221 is used to expose the insulating material in the opening 201, so that the insulating material contacts the second release layer 221, which is beneficial to the separation of the molded insulating part 100 from the second release layer 221.

[0104] In some embodiments, the carrier 200 includes a plurality of openings 201 arranged along a second direction Y, where the second direction Y is perpendicular to the first direction X.

[0105] In some embodiments, the release force F1 between the first release layer 211 and the insulating material is 3g / 25mm≤F1≤300g / 25mm. This can better reduce the adhesion between the insulating material in the injection part 1 and the carrier 200 and reduce the residual insulating material around the opening 201.

[0106] Optionally, F1 can be 3g / 25mm, 4g / 25mm, 5g / 25mm, 6g / 25mm, 7g / 25mm, 8g / 25mm, 9g / 25mm, 10g / 25mm, 11g / 25mm, 12g / 25mm, 13g / 25mm, 14g / 25mm, 15g / 25mm, 16g / 25mm, 17g / 25mm, 18g / 25mm, 19g / 25mm,

[0107] The range of any one of 20g / 25mm…297g / 25mm, 298g / 25mm, 299g / 25mm, 300g / 25mm or any two of them.

[0108] In some embodiments, the first composite layer 210 includes a first base layer 212 . The first release layer 211 and the first base layer 212 are arranged along a first direction X. The first base layer 212 is connected to the first release layer 211 .

[0109] In some embodiments, the thickness H1 of the first base layer 212 is 10 μm≤H1≤200 μm along the first direction X. By limiting 10 μm≤H1≤200 μm, the thickness of the insulating member 100 is limited, the insulating member 100 is easily pasted, and the space occupied by the insulating member 100 is reduced.

[0110] Optionally, H1 can be any one of 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, and 200μm, or a range consisting of any two of them.

[0111] In some embodiments, 20 μm≤H1≤100 μm, which further limits the thickness of the insulating member 100 , thereby facilitating better adhesion of the insulating member 100 and reducing the space occupied by the insulating member 100 .

[0112] In some embodiments, the material of the first release layer 211 includes siloxane, which reduces the adhesion between the insulating material and the first base layer 212 and reduces the residual insulating material around the opening 201 , which helps the injection component 1 to scrape the insulating material into the opening 201 .

[0113] In some embodiments, the material of the first base layer 212 includes one or more of polyethylene terephthalate, polyimide, polytetrafluoroethylene, polyetheretherketone, polyphenylene sulfide, liquid crystal polymer, and polybenzimidazole.

[0114] In some embodiments, the first composite layer 210 includes a first adhesive layer 213, and the first adhesive layer 213 connects the first base layer 212 and the second release layer 221. The adhesion force F2 between the first adhesive layer 213 and the second release layer 221 is 0.001N / mm≤F2≤0.1N / mm. If the adhesion force is too small, the first base layer 212 and the second release layer 221 are easily separated when scraping the insulating material, rolling up the carrier 200, etc. When the insulating member 100 is used, the first base layer 212 and the second release layer 221 need to be separated and the insulating member 100 is exposed. If the adhesion force is too large, it is not easy to separate the first base layer 212 from the second release layer 221, which affects the adhesion of the insulating member 100. By limiting 0.001N / mm≤F2≤0.1N / mm, the separation of the first base layer 212 and the second release layer 221 when scraping into the insulating material or rolling up the carrier 200 can be reduced, and the first base layer 212 and the second release layer 221 can be more easily separated when pasting the insulating member 100.

[0115] Optionally, F2 can be 0.001 N / mm, 0.005 N / mm, 0.01 N / mm, 0.015 N / mm, 0.02 N / mm, 0.025 N / mm, 0.03 N / mm, 0.035 N / mm, 0.04 N / mm, 0.045 N / mm, 0.05 N / mm, 0.055 N / mm, 0.06 N / mm, 0.065 N / mm, 0.07 N / mm, 0.075 N / mm,

[0116] The range is any one of 0.08 N / mm, 0.085 N / mm, 0.09 N / mm, 0.095 N / mm, and 0.1 N / mm, or any two of them.

[0117] In some embodiments, the thickness W of the first adhesive layer 213 is 3μm≤W≤5μm. If the thickness of the first adhesive layer 213 is too small, the connection between the first base layer 212 and the second release layer 221 will be affected. If the thickness of the first adhesive layer 213 is too large, when the first base layer 212 and the second release layer 221 are separated, the residual adhesive of the first adhesive layer 213 is likely to take away the insulating member 100. By limiting 3μm≤W≤5μm, the first base layer 212 and the second release layer 221 can be better connected, reducing the possibility of the residual adhesive of the first adhesive layer 213 taking away the insulating member 100.

[0118] Optionally, W may be any one of 3 μm, 3.2 μm, 3.4 μm, 3.6 μm, 3.8 μm, 4 μm, 4.2 μm, 4.4 μm, 4.6 μm, 4.8 μm, and 5 μm, or a range consisting of any two of them.

[0119] In some embodiments, the release force F3 between the second release layer 221 and the insulating material is 50g / 25mm≤F3≤500g / 25mm. If the release force F3 is too small, the insulating member 100 is easy to separate from the second release layer 221, and the insulating member 100 is easy to fall off from the opening 201 during the winding process. If the release force F3 is too large, it is not easy to separate the insulating member 100 from the second release layer 221 after the insulating member 100 is pasted, and the second release layer 221 is easy to pull the insulating member 100, causing the insulating member 100 to deform and affect the pasting of the insulating member 100. By limiting 50g / 25mm≤F3≤150g / 25mm, the insulating member 100 can be better arranged in the opening 201, and it is easy to separate from the second release layer 221 after the insulating member 100 is pasted.

[0120] Optionally, F3 can be 50g / 25mm, 52g / 25mm, 54g / 25mm, 56g / 25mm, 58g / 25mm, 60g / 25mm, 62g / 25mm, 64g / 25mm, 66g / 25mm, 68g / 25mm,

[0121] 70g / 25mm, 72g / 25mm, 74g / 25mm, 76g / 25mm, 78g / 25mm, 80g / 25mm,

[0122] 82g / 25mm, 84g / 25mm, 86g / 25mm, 88g / 25mm, 90g / 25mm, 92g / 25mm,

[0123] 94g / 25mm, 96g / 25mm, 98g / 25mm, 100g / 25mm, 102g / 25mm, 104g / 25mm,

[0124] 106g / 25mm, 108g / 25mm, 110g / 25mm, 112g / 25mm, 114g / 25mm, 116g / 25mm, 118g / 25mm, 120 g / 25mm, 122g / 25mm, 124g / 25mm, 126g / 25mm, 128g / 25mm, 130g / 25mm, 132g / 25mm, 134g / 25 The range of any one of or any two of 150g / 25mm, 162g / 25mm, 168g / 25mm, 172g / 25mm, 176g / 25mm, 178g / 25mm, 180g / 25mm, 181g / 25mm, 182g / 25mm, 183g / 25mm, 184g / 25mm, 186g / 25mm, 187g / 25mm, 188g / 25mm, 189g / 25mm, 200g / 25mm, 201g / 25mm, 202g / 25mm, 203g / 25mm, 204g / 25mm, 205g / 25mm, 206g / 25mm, 207g / 25mm, 208g / 25mm, 209g / 25mm, 210g / 25mm, 211g / 25mm

[0125] In some embodiments, the second composite layer 220 includes a second base layer 222, the second base layer 222 is connected to the second release layer 221, and the thickness H2 of the second base layer 222 along the first direction X is 30μm≤H2≤80μm. The carrier 200 is set as a roll material, and the injection part 1 scrapes the insulating material into the opening 201 during the tape running process. The second base layer 222 carries the insulating part 100. By limiting 30μm≤H2≤80μm, the second base layer 222 can be stretched and deformed during the tape running process, thereby reducing the impact on the molding of the insulating part 100 and helping to control costs.

[0126] Optionally, H2 can be any one of 30μm, 32μm, 34μm, 36μm, 38μm, 40μm, 42μm, 44μm, 46μm, 48μm, 50μm, 52μm, 54μm, 56μm, 58μm, 60μm, 62μm, 64μm, 66μm, 68μm, 70μm, 72μm, 74μm, 76μm, 78μm, and 80μm, or a range of any two of them.

[0127] In some embodiments, the thickness of the second base layer 222 is greater than the thickness of the first base layer 212 .

[0128] In some embodiments, the material of the second release layer 221 includes siloxane, which is helpful to reduce the adhesion between the insulating material and the second base layer 222 and facilitate separation of the insulating member 100 .

[0129] In some embodiments, the material of the second base layer 222 includes one or more of polyethylene terephthalate, polyimide, polytetrafluoroethylene, polyetheretherketone, polyphenylene sulfide, liquid crystal polymer, and polybenzimidazole.

[0130] In some embodiments, when viewed along the first direction X, the shape of the opening 201 includes any one of a triangle, a rectangle, a circle, an ellipse, and a special shape.

[0131] In some embodiments, the opening 201 is formed by die cutting or laser etching.

[0132] In some embodiments, the insulating material is in a molten state when scraped into the opening 201 , and the melting point of the insulating material is lower than that of the first base layer 212 , thereby reducing the effect of temperature on the first base layer 212 and the possibility of adhesion between the insulating material and the first base layer 212 .

[0133] In some embodiments, the melting point of the insulating material is lower than that of the second base layer 222 , which reduces the effect of temperature on the second base layer 222 , helps the second base layer 222 to carry the insulating member 100 , and reduces deformation of the insulating member 100 .

[0134] See also Figure 5 An embodiment of the present application provides a battery cell 300, comprising a first pole piece 310 and an insulating member 100 in any one of the above embodiments.

[0135] The battery cell 300 includes a battery cell housing 301 , an electrode assembly (not shown) and an electrode terminal 302 . The electrode assembly is disposed in the battery cell housing 301 . The electrode terminal 302 is connected to the electrode assembly and extends out of the battery cell housing 301 .

[0136] In one embodiment, the battery cell 300 includes two electrode terminals 302, and the two electrode terminals 302 have opposite polarities. Optionally, the two electrode terminals 302 extend from different sides of the battery cell housing 301. Optionally, the two electrode terminals 302 extend from the same side of the battery cell housing 301.

[0137] In some embodiments, through the tensile strength P of the insulating member 100, P≥3Mpa, after the insulating member 100 is hot pressed, the stress concentration area on the surface of the insulating member 100 and the edge of the electrode terminal 302 is not easily cracked, and the battery cell 300 is not easily cracked after aging tests such as hot and cold shock.

[0138] In some embodiments, the thermal shock test method is as follows: the battery cell 300 is kept in an environment of 85±3°C for 30 minutes, and the temperature conversion time is ≤30 minutes; the battery cell 300 is kept in an environment of -40±3°C for 30 minutes, and the temperature conversion time is ≤30 minutes; the above steps are repeated for 96 cycles.

[0139] In some embodiments, the electrode assembly includes a first pole piece 310, a second pole piece (not shown) and a separator (not shown), the first pole piece 310, the separator and the second pole piece are sequentially stacked to form an electrode assembly unit, and a plurality of electrode assembly units are stacked to form an electrode assembly. In other embodiments, the electrode assembly is a winding structure, and the electrode assembly is formed by sequentially stacking the first pole piece 310, the separator and the second pole piece and then winding them.

[0140] See also Figure 6 In some embodiments, the first pole piece 310 includes a current collector 311 and an active material layer 312. The current collector 311 includes a first section 311a and a second section 311b arranged along a first direction X, and the active material layer 312 is arranged on the surface of the first section 311a. The insulating member 100 is at least arranged in the second section 311b to insulate and protect the second section 311b, thereby reducing the risk of burrs piercing the isolation film and causing the second section 311b to contact and short-circuit with the second pole piece. The first direction X is the length direction or width direction of the first pole piece 310.

[0141] In some embodiments, the insulating member 100 partially covers the second section 311 b and partially connects to a side of the active material layer 312 away from the current collector 311 , further reducing the risk of short circuit.

[0142] In some embodiments, along the second direction Y, at least a portion of the second segment 311 b is disposed between two insulating members 100 .

[0143] In one embodiment, the active material layer 312 is coated on the first section 311 a by extrusion coating, transfer coating, spray coating, or the like.

[0144] See also Figure 7 In some embodiments, the current collector 311 includes a third section 311c, and the third section 311c is connected to the second section 311b. The battery cell 300 includes an electrical connector 320, which is disposed in the third section 311c. The insulating member 100 covers a portion of the electrical connector 320 to insulate and protect the electrical connector 320.

[0145] In some embodiments, part of the insulating member 100 extends to the side of the active material layer 312 away from the current collector 311 , and another part extends to the electrical connector 320 , so that the second section 311 b is covered by the insulating member 100 , which is beneficial to insulation.

[0146] In some embodiments, along the first direction X, the insulating member 100 overlaps the active material layer 312 by a width d1 of 0.1 mm ≤ d1 ≤ 2 mm.

[0147] In one embodiment, the electrical connector 320 is welded to the third section 311c to form a welding area 320a. The insulating member 100 covers the welding area 320a along the second direction Y to insulate and protect the welding area 320a. The second direction Y is perpendicular to the first direction X, and the second direction Y is the thickness direction of the battery cell 300.

[0148] In some embodiments, the welding region 320a includes a welding mark 3201, and the insulating member 100 covers the welding mark 3201, thereby reducing the risk of the welding mark 3201 piercing the isolation membrane.

[0149] In some embodiments, the electrical connector 320 is formed by die cutting, and the electrode terminal 302 is connected to the electrical connector 320. The insulating member 100 can wrap the burrs of the electrical connector 320 to reduce the risk of the burrs piercing the isolation film.

[0150] In some embodiments, the first pole piece 310 includes a primer layer 313, which is disposed in the second section 311b to reduce the risk of burrs piercing the isolation membrane, resulting in a short circuit between the second section 311b and the second pole piece. The insulating member 100 connects the primer layer 313 and the electrical connector 320, further reducing the risk of burrs piercing the isolation membrane.

[0151] See also Figure 8 In some embodiments, along the first direction X, a gap d2 is formed between the insulating member 100 and the active material layer 312 , and 0 mm ≤ d2 ≤ 0.7 mm.

[0152] Optionally, d2 may be any one of 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, and 0.7 mm, or a range consisting of any two of the two.

[0153] In some embodiments, the current collector 311 includes a polymer layer (not shown) and two metal layers (not shown), the polymer layer is located between the two metal layers, and the active material layer 312 is disposed on the surface of the metal layer.

[0154] In some embodiments, electrical connector 320 connects the metal layers.

[0155] See also Fig. 9 In some embodiments, the battery cell 300 includes at least two insulating members 100 , and along the second direction Y, the electrical connector 320 is located between the two insulating members 100 .

[0156] In some embodiments, along the second direction Y, the insulating member 100 includes a first region 110 , and the first region 110 extends along the first direction X beyond the third section 311 c .

[0157] In some embodiments, the first region 110 includes a first sub-region 110a, and along the second direction Y, the projection of the first sub-region 110a is separated from or does not overlap with the projection of the electrical connector 320. Along the second direction Y, the first sub-regions 110a of two adjacent insulating members 100 are connected. Through the connection of the two first sub-regions 110a, the two sides of the electrical connector 320 along the third direction Z are covered, reducing the risk of burrs on the electrical connector 320 piercing the isolation film. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0158] In some embodiments, when the battery cell 300 is at a high temperature, the isolation film shrinks due to the heat. The insulating member 100 can reduce the risk of burrs on the first pole piece 310 and the weld mark 3201 short-circuiting with the second pole piece due to the shrinkage of the isolation film.

[0159] In some embodiments, the bonding force F between the insulating member 100 and the electrical connector 320 is F ≥ 0.08 N / mm, which helps to reduce the risk of the insulating member 100 detaching and causing a short circuit between the first pole piece 310 and the second pole piece.

[0160] In some embodiments, after the insulating part 100 is immersed in a 85°C DMC solution for 24 hours, the adhesion force F between the insulating part 100 and the electrical connector 320 is ≥0.06N / mm, which is beneficial to reduce the risk of the insulating part 100 detaching during long-term cycle use of the battery cell, resulting in a short circuit between the first pole piece 310 and the second pole piece.

[0161] The present application will be further described below through specific embodiments.

[0162] 100 insulating parts of 100 are produced with materials of different viscosities and mass proportions of inorganic fillers, and the molding quantity is recorded.

[0163] The formed insulating member 100 is subjected to a tensile strength test. The tensile strength test method is as follows: the two ends of the insulating member 100 are clamped by a tensile machine, and the insulating member 100 is stretched until the insulating member 100 breaks, the stretching speed is 50 mm / min, the test sample width is 3 mm, and the tensile strength of the insulating member 100 in the corresponding embodiment is recorded.

[0164] Viscosity test method: Weigh 100 g of insulating part 100, put the insulating part 100 into the aluminum can of the rotational viscometer, adjust the rotation speed of the rotational viscometer equipment to 12 RPM, put the aluminum can into the heating furnace and cover it with an insulation cap, heat it to 190°C, keep it for 10 minutes, and use the SC4-27 model rotor to detect the viscosity of the insulating part.

[0165] Table 1

[0166]

[0167]

[0168] It can be seen from Examples 1 to 5 in Table 1 that when heated to 190° C. and melted, the viscosity of the insulating member 100 after melting is in the range of 1000 cps to 5000 cps, and the insulating member 100 is easier to form, which is beneficial to production.

[0169] It can be seen from Examples 8 to 11 that the addition ratio of inorganic filler is in the range of 5% to 10%, which is beneficial to improving the tensile strength P of the insulating member 100, facilitating the molding of the insulating member 100 and preventing the insulating member 100 from cracking, which is beneficial to insulation.

[0170] It can be seen from Comparative Example 1 and Examples 1 to 5 that when the tensile strength P of the insulating member is P≥3MPa, the insulating member 100 is not easily deformed or broken during use, which is beneficial to insulation.

[0171] See also Fig.10 The present application also provides a method for manufacturing a battery cell 300, comprising the following steps:

[0172] Step 1: forming the first pole piece 310 by coating, cold pressing and slicing;

[0173] Step 2: Bond the insulating member 100 to the second section 311b;

[0174] Step 3: Separate the second release layer 221 and the insulating member 100 .

[0175] In some embodiments, step 1 specifically includes: uniformly coating the prepared slurry on the pretreated current collector 311 , rolling the dried electrode sheet, and slicing the rolled electrode sheet according to size to form a first electrode sheet 310 .

[0176] In some embodiments, step 2 specifically includes: peeling off the first release layer 211 to expose the insulating member 100 , and activating the adhesiveness of the insulating member 100 by heat conduction by hot pressing the second release layer 221 , thereby bonding the insulating member 100 to the second section 311 b .

[0177] In some embodiments, the viscous activation temperature T of the insulating member 100 is 60° C. ≤ T ≤ 100° C.

[0178] Optionally, T may be any one of 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, or a range consisting of any two of them.

[0179] In some embodiments, the pressure F4 of hot pressing the second release layer 221 is 0.05 MPa≤F4≤0.6 MPa.

[0180] Optionally, F4 can be any one of 0.05 MPa, 0.1 MPa, 0.15 MPa, 0.2 MPa, 0.25 MPa, 0.3 MPa, 0.35 MPa, 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa, and 0.6 MPa, or a range consisting of any two of them.

[0181] In some embodiments, the following steps are included between step 1 and step 2: welding two electrical connectors 320 to connect two sides of the third section 311 c and form a weld mark 3201. Covering the weld mark 3201 with the insulating member 100.

[0182] See also Fig.11 The present application also provides an electrical device 400 using the above-mentioned battery cell 300.

[0183] In one embodiment, the electrical equipment 400 of the present application may be, but is not limited to, electronic equipment, drones, backup power supplies, electric vehicles, electric motorcycles, electric power-assisted bicycles, electric tools, large household batteries, etc.

[0184] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present application, and are not used as limitations on the present application. As long as they are within the spirit of the present application, appropriate changes and modifications to the above embodiments are within the scope of the present application.

Claims

1. An insulating member, characterized in that: The insulating member is configured to be heated to 190° C. and kept melted for 10 minutes, and the viscosity of the insulating member after melting is 1000 cps to 5000 cps.

2. The insulating member according to claim 1, characterized in that The tensile strength P of the insulating member is P≥3MPa.

3. The insulating member according to claim 1, characterized in that The material of the insulating part includes one or more of modified polypropylene, modified polyethylene, modified ethylene elastomer, modified propylene elastomer, modified styrene elastomer, modified ionomer resin, modified polyvinylidene fluoride, modified vinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate and modified polyethylene glycol.

4. The insulating member according to claim 3, characterized in that The material used for modification includes one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride and epoxy group.

5. The insulating member according to claim 1, characterized in that The insulating member includes an inorganic filler, and the inorganic filler includes one or more of boehmite, silicon dioxide, calcium carbonate, talc, wollastonite, quartz powder, alumina, mica powder, titanium dioxide and glass fiber.

6. The insulating member according to claim 5, characterized in that Based on the total mass of the insulating member, the mass proportion of the inorganic filler is 5% to 10%.

7. The insulating member according to claim 1, characterized in that The thickness d of the insulating member is 10 μm≤d≤200 μm.

8. The insulating member according to claim 7, characterized in that The thickness d of the insulating member is 10 μm≤d≤50 μm.

9. The insulating member according to claim 1, characterized in that: The melting point T of the insulating member is 100°C≤T≤200°C.

10. The insulating member according to claim 1, wherein The viscosity test method is as follows: take 10-11g of the insulating part, put the insulating part into the aluminum can of the rotational viscometer, adjust the rotation speed of the rotational viscometer equipment to 12RPM, put the aluminum can into a heating furnace and cover it with an insulation cap and heat it to 190°C, keep it for 10 minutes, and use an SC4-27 model rotor for detection.

11. A battery cell, characterized in that: comprising a first pole piece and an insulating member as claimed in any one of claims 1 to 10; The first electrode sheet includes a current collector and an active material layer, the current collector includes a first section and a second section arranged along a first direction, and the active material layer is arranged on a surface of the first section. The insulating member is at least arranged in the second section, and the first direction is the length direction or the width direction of the first pole piece.

12. The battery cell according to claim 11, characterized in that: The battery core includes an electrical connector, the current collector includes a third section, the third section is connected to the second section, the electrical connector is arranged in the third section, and the insulating member covers a portion of the electrical connector.

13. The battery cell according to claim 12, characterized in that: Along the first direction, the insulating member overlaps the active material layer by a width d1 of 0.1 mm ≤ d1 ≤ 2 mm.

14. The battery cell according to claim 12, characterized in that: The electrical connector is welded to the third section to form a welding area, and the insulating member covers the welding area.

15. The battery cell according to claim 14, characterized in that: The battery core comprises at least two insulating members, and the electrical connector is located between the two insulating members along a second direction, and the second direction is a thickness direction of the battery core; Along the first direction, the insulating member includes a first region, and the first region extends out of the third section along the first direction; The first region includes a first sub-region, and along the second direction, a projection of the first sub-region is separated from a projection of the electrical connector; Along the second direction, the first sub-regions of two adjacent insulating members are connected.

16. The battery cell according to claim 15, characterized in that: Along the second direction, at least a portion of the second section is disposed between the two insulating members.

17. The battery cell according to claim 12, characterized in that: The bonding force F between the insulating component and the electrical connector is F≥0.08N / mm.

18. The battery cell according to claim 12, characterized in that: The current collector comprises a polymer layer and two metal layers, the polymer layer is located between the two metal layers, and the active material layer is arranged on the surface of the metal layer.

19. The battery cell according to claim 12, characterized in that: The first pole piece includes a bottom coating layer, the bottom coating layer is arranged in the second section, and the insulating member connects the bottom coating layer and the electrical connector along a second direction, and the second direction is a thickness direction of the battery cell.

20. The battery cell according to claim 11, characterized in that: Along the first direction, a gap d2 is formed between the insulating member and the active material layer, and 0 mm ≤ d2 ≤ 0.7 mm.

21. The battery cell according to claim 12, characterized in that: After the first pole piece bonded with the insulating component is immersed in a 85° C. DMC solution for 24 hours, the bonding force F between the insulating component and the electrical connector is ≥0.06 N / mm.

22. The battery cell according to claim 12, characterized in that: The insulating member is attached to the second section.

23. A method for manufacturing a battery cell according to any one of claims 11 to 22, wherein the insulating member is disposed on a carrier, characterized in that: The steps include: Step 1: forming the first pole piece by coating and cold pressing; Step 2: bonding the insulating member to the second section; Step 3: Separating the carrier and the insulating member.

24. The method for manufacturing a battery cell as claimed in claim 23, characterized in that: The following steps are included between step 1 and step 2: welding the two electrical connectors on both sides of the third section to form the welding area, and the insulating member covers the welding area.

25. An electrical device, characterized in that: Comprising the battery cell as claimed in any one of claims 11 to 22.

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