Insulating member, battery cell, manufacturing method therefor, and electrical device

Abstract

Disclosed in the present application are an insulating member, a battery cell, a manufacturing method therefor, and an electrical device. The insulating member is configured to be heated to 190°C and kept molten for 10 minutes, the viscosity of the molten insulating member being 1000 cps to 5000 cps. An insulating member of too low viscosity is not easy to mold, while an insulating material of two high viscosity exhibits bad fluidity, and is less prone to flow out of an injection member, and difficult to produce. In the present application, the viscosity of the molten insulating member is limited to 1000 cps to 5000 cps, thereby helping to mold the insulating member and aiding in production.

Description

Insulating piece, battery cell, manufacturing method thereof and electric device TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to an insulating piece, a battery cell, a manufacturing method thereof and an electric device. BACKGROUND

[0002] In a secondary battery, internal short circuit is the most common source of safety problems such as fire, and among them, the mode of short circuit that produces the most heat and is most prone to fire and explosion is the short circuit caused by the contact of the positive electrode foil and the negative electrode. At present, in order to reduce the risk of short circuit of the battery cell, an insulating piece is usually pasted in the battery cell. SUMMARY

[0003] Therefore, it is necessary to provide an insulating piece, a battery cell, a manufacturing method thereof and an electric device, which are beneficial to the molding of the insulating piece and facilitate production.

[0004] Embodiments of the present application provide an insulating piece configured to be heated to 190°C, kept for 10 minutes to melt, and the viscosity of the insulating piece after melting is 1000cps to 5000cps. If the viscosity is too small, the insulating piece is not easy to mold, and if the viscosity is too large, the flowability of the insulating material is poor and it is not easy to flow out of the glue injection piece, which is difficult to produce. By limiting the viscosity of the insulating piece after melting to 1000cps to 5000cps, the insulating piece is beneficial to molding and facilitates production.

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

[0006] In one or more optional embodiments above, the material of the insulating piece 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 polyvinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate and modified polyethylene glycol, which is beneficial to improving the adhesion of the insulating piece.

[0007] In one or more optional embodiments above, the modified material includes one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride and epoxy groups, and the modified material has adhesion to metal, which is beneficial to improving the adhesion of the insulating piece.

[0008] In one or more optional embodiments above, the insulating piece includes inorganic fillers, and the inorganic fillers include one or more of boehmite, silicon dioxide, calcium carbonate, talc powder, wollastonite, quartz powder, aluminum hydroxide, mica powder, titanium white powder and glass fiber.

[0009] In one or more optional embodiments above, the mass percentage of the inorganic filler is 5-10% based on the total mass of the insulating member. Increasing the hardness of the insulating member improves the situation that the insulating member is easily deformed or missing during the pasting process, and reduces the situation that the insulating member is too hard to cause the insulating member to be easily cracked, for example, when the insulating member is pasted in the battery cell, after soaking in the 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 10-200 μm. In this way, the insulation performance of the insulating member can be improved, and the space occupied by the insulating member is reduced.

[0011] In one or more optional embodiments above, the thickness d of the insulating member is 10-50 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 optional embodiments above, the melting point T of the insulating member is 100-200℃, which is not easy to melt and shrink during use, and is conducive to playing an insulating role.

[0013] Embodiments of the present application provide a battery cell, which includes a first pole piece and an insulating member according to any one of the above embodiments. The first pole piece 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, the active material layer is arranged on the surface of the first section, and the insulating member is arranged at least on the second section. The first direction is the length direction or the width direction of the first pole piece, the second section is insulated and protected, and the risk of short circuit caused by the burr piercing the isolation film to cause the second section to contact the second pole piece is reduced.

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

[0015] In one or more optional embodiments above, along the first direction, the width d1 of the overlap between the insulating member and the active material layer is 0.1-2 mm, which is conducive to avoiding improving the insulation reliability.

[0016] In one or more optional embodiments above, the electrical connection member is welded to 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 electric core comprises at least two insulating pieces, and the electric connecting piece is located between the two insulating pieces in the second direction. The second direction is the thickness direction of the electric core. In the first direction, the insulating piece comprises a first region, and the first region extends a third section in the first direction in the second direction. The first region comprises a first sub-region, and a projection of the first sub-region is separated from a projection of the electric connecting piece in the second direction. The first sub-regions of the two adjacent insulating pieces are connected in the second direction. By connecting the two first sub-regions, the covering electric connecting piece covers two sides of the electric connecting piece in the third direction, thereby reducing the risk of the burr on the electric connecting piece piercing the isolation film.

[0018] In one or more optional embodiments above, at least part of the second section is arranged between the two insulating pieces in the second direction.

[0019] In one or more optional embodiments above, the adhesion F between the insulating piece and the electric connecting piece is F≥0.08 N / mm, which is conducive to reducing the risk of short circuit between the first and second pole pieces caused by the separation of the insulating piece.

[0020] In one or more optional embodiments above, 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.

[0021] In one or more optional embodiments above, the first pole piece comprises a primer layer arranged on the second section, thereby reducing the risk of the burr piercing the isolation film to cause the second section to be in contact with the second pole piece and short circuit. In the second direction, the insulating piece connects the primer layer and the electric connecting piece, thereby further reducing the risk of the burr piercing the isolation film.

[0022] In one or more optional embodiments above, in the first direction, the insulating piece has a gap d2 of 0 mm≤d2≤0.7 mm with the active material layer. The insulating piece does not overlap the active material layer, which can avoid increasing the thickness of the electric core. If the gap exceeds 0.7 mm, the first pole piece, the primer layer, the electric connecting piece, and the insulating piece are likely to be folded due to the too large gap, thereby causing a safety risk.

[0023] In one or more optional embodiments above, after the first pole piece with the insulating piece is soaked in a 85℃ DMC solution for 24 hours, the adhesion F between the insulating piece and the electric connecting piece is F≥0.06 N / mm, which is conducive to reducing the risk of short circuit between the first and second pole pieces caused by the separation of the insulating piece due to the soaking of the electrolyte during the use of the electric core.

[0024] In one or more optional embodiments above, the insulating piece is attached to the second section. The attachment refers to arranging the insulating piece on the second section by means of adhesion.

[0025] The embodiments of the present application provide a manufacturing method of the battery cell of any one of the above embodiments, the insulating member is arranged on the carrier, and the manufacturing method comprises 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 manufacturing method of the battery cell of any one of the above embodiments, between the step 1 and the step 2, the method further comprises the following step: welding two electrical connectors on two sides of the third section to form welding areas, and the insulating member covers the welding areas.

[0027] The embodiments of the present application provide a use-electricity device comprising the battery cell of any one of the above embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0028] FIG. 1 shows a structural schematic diagram of a carrier and an insulating member in some embodiments of the present application.

[0029] FIG. 2 shows a cross-sectional schematic diagram of a carrier and an insulating member in some embodiments of the present application.

[0030] FIG. 3 shows a structural schematic diagram of a carrier and an insulating member in some embodiments of the present application.

[0031] FIG. 4 shows a flow schematic diagram of a manufacturing method of an insulating member in some embodiments of the present application.

[0032] FIG. 5 shows a structural schematic diagram of a battery cell in some embodiments of the present application.

[0033] FIG. 6 shows a partial cross-sectional schematic diagram of a battery cell in some embodiments of the present application.

[0034] FIG. 7 shows a partial cross-sectional schematic diagram of a battery cell in some embodiments of the present application.

[0035] FIG. 8 shows a partial cross-sectional schematic diagram of a battery cell in some embodiments of the present application.

[0036] FIG. 9 shows a partial structural schematic diagram of a battery cell in some embodiments of the present application.

[0037] FIG. 10 shows a flow schematic diagram of a manufacturing method of a battery cell in some embodiments of the present application.

[0038] FIG. 11 shows a structural schematic diagram of a use-electricity device in some embodiments of the present application.

[0039] Main element symbol explanation: Insulating part 100 First region 110 First sub-region 110a Carrier 200 First composite layer 210 Opening 201 First release layer 211 First base layer 212 First adhesive layer 213 Second composite layer 220 Second release layer 221 Second base layer 222 Electric core 300 Electric core shell 301 Electric pole terminal 302 First pole piece 310 Current collector 311 Active material layer 312 Primer layer 313 First section 311a Second section 311b Third section 311c Electric connection 320 Welding area 320a Welding mark 3201 Glue injection part 1 First direction X Second direction Y

[0040] The following specific embodiments will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0041] The following detailed description is presented for purposes of illustration and description. It is not intended to limit the application in scope to the exact details shown and described. Various embodiments presented herein can be combined in order to achieve further embodiments.

[0042] When an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to or "coupled" to another element, it can be directly connected to the other element or intervening elements can also be present.

[0043] It will be understood that the term "vertical" is used herein to describe a relationship of ideal state between two components. In actual production or use state, there can be a state similar to vertical or equal between two components. For example, in combination with numerical description, vertical can refer to the included angle between two straight lines in the range of 90°±10°, vertical can also refer to the dihedral angle between two planes in the range of 90°±10°, and vertical can also refer to the included angle between a straight line and a plane in the range of 90°±10°. The two components described as "vertical" can not be absolute straight lines or planes, but can be approximately straight lines or planes, and as a whole, the overall extension direction is a straight line or a plane, which can be considered as a "straight line" or a "plane".

[0044] Unless otherwise defined, the term "plurality" as used herein, when used to describe a number of components, specifically refers to two or more of the components.

[0045] Some embodiments of the present application will be described in detail with reference to the drawings, which are provided for purposes of illustration only and in no way limit the scope of the application. The following embodiments and features of the embodiments can be combined with each other in the case of no conflict.

[0046] Referring to FIGS. 1 and 3, the first embodiment of the present application provides an insulating piece 100 configured to be heated to 190°C, kept for 10 minutes to melt, and the viscosity of the insulating piece 100 after melting is 1000cps to 5000cps. If the viscosity is too small, the insulating piece 100 is not easy to shape, and if the viscosity is too large, the flowability of the insulating material is poor, and it is not easy to flow out from the glue injection piece 1, which is difficult to produce. By limiting the viscosity of the insulating piece 100 after melting to 1000cps to 5000cps, the insulating piece 100 is shaped, which is convenient for production.

[0047] Optionally, the viscosity of the insulation piece 100 after melting can be any one or a range between any two of 1000 cps, 1100 cps, 1200 cps, 1300 cps, 1400 cps, 1500 cps, 1600 cps, 1700 cps, 1800 cps, 1900 cps, 2000 cps, 2100 cps, 2200 cps, 2300 cps, 2400 cps, 2500 cps, 2600 cps, 2700 cps, 2800 cps, 2900 cps, 3000 cps, 3100 cps, 3200 cps, 3300 cps, 3400 cps, 3500 cps, 3600 cps, 3700 cps, 3800 cps, 3900 cps, 4000 cps, 4100 cps, 4200 cps, 4300 cps, 4400 cps, 4500 cps, 4600 cps, 4700 cps, 4800 cps, 4900 cps, and 5000 cps.

[0048] In some embodiments, the tensile strength P of the insulation piece 100 is greater than or equal to 3 MPa, so that the insulation piece 100 is not easily deformed or broken in use, which is beneficial to insulation.

[0049] In some embodiments, the insulation material 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 polyvinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate, and modified polyethylene glycol, which is beneficial to improve the adhesion of the insulation piece 100.

[0050] In some embodiments, the modified material includes one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride, and epoxy groups, and the modified material has adhesion to metal, which is beneficial to improve the adhesion of the insulation piece 100.

[0051] In some embodiments, the insulation material includes inorganic fillers, and the inorganic fillers include one or more of boehmite, silica, calcium carbonate, talc powder, wollastonite, quartz powder, aluminum hydroxide, mica powder, titanium white powder, and glass fiber.

[0052] In some embodiments, the mass percentage of the inorganic fillers based on the total mass of the insulation piece 100 is 5% to 10%. Increasing the hardness of the insulation piece 100 improves the deformation and loss of the insulation piece 100 during the pasting process, and reduces the cracking of the insulation piece 100 due to the insulation piece 100 being too hard, for example, when the insulation piece 100 is pasted in the battery cell, if the insulation piece 100 is too hard, it is easy to crack after soaking in the electrolyte.

[0053] Optionally, the mass percentage of the inorganic filler can be any one or a range between any two of 5%, 6%, 7%, 8%, 9%, and 10%.

[0054] In some embodiments, the thickness d of the insulating member 100 is 10 pm ≤ d ≤ 200 pm. In this way, the insulation performance of the insulating member 100 can be improved, and the space occupied by the insulating member 100 can be reduced.

[0055] Optionally, d can be any one or a range between any two of 10 pm, 20 pm, 30 pm, 40 pm, 50 pm, 60 pm, 70 pm, 80 pm, 90 pm, 100 pm, 110 pm, 120 pm, 130 pm, 140 pm, 150 pm, 160 pm, 170 pm, 180 pm, 190 pm, and 200 pm.

[0056] In some embodiments, 10 pm ≤ d ≤ 50 pm. In this way, the insulation performance of the insulating member 100 can be improved, and the space occupied by the insulating member 100 can be further reduced.

[0057] In some embodiments, the width h of the insulating member 100 is 1.5 mm ≤ h ≤ 10 mm.

[0058] Optionally, h can be any one or a range between any two of 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9.0 mm, 9.5 mm, and 10 mm.

[0059] In some embodiments, the length l of the insulating member 100 is 3 mm ≤ h ≤ 20 mm.

[0060] Optionally, l can be any one or a range between any two of 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, and 20 mm.

[0061] In some embodiments, the melting point T of the insulating member 100 is 100℃ ≤ T ≤ 200℃. In use, the insulating member 100 is less likely to melt and shrink, which is conducive to the insulation function. For example, the insulating member 100 does not undergo thermal shrinkage during use of the battery cell, reducing the occurrence of short circuits.

[0062] Optionally, T can be any one or a range between any two of 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, and 200℃.

[0063] Referring to FIG. 1 and FIG. 4, the application provides a manufacturing method of the insulation piece 100, comprising the following steps:

[0064] Step 1: heating the insulation material to melt, and injecting the melted insulation material into the opening 201 of the carrier 200;

[0065] Step 2: forming the insulation piece 100 after the insulation material is cooled.

[0066] In some embodiments, the insulation material is heated to 190°C in step 1, and kept for 10 minutes to melt.

[0067] Referring to FIG. 3, in some embodiments, step 1 injects the insulation material into the opening 201 of the carrier 200 through the glue injection part 1.

[0068] In some embodiments, step 1 specifically comprises heating the insulation material to 190°C, and finally flowing out the insulation material through the glue outlet by air pressure and gear pump, coating on the surface of the carrier 200, pulling the carrier 200 by the equipment, and making the carrier 200 pass through the glue injection part 1, and the glue injection part 1 abuts against the surface of the carrier 200, and scraping the insulation material into the opening 201 when the opening 201 passes through the glue injection part 1.

[0069] In some embodiments, step 2 specifically comprises solidifying to form the insulation piece 100 after air cooling.

[0070] In some embodiments, the thickness of the glue injection part 1 is greater than the width of the opening 201, which is beneficial to scraping the insulation material into the opening 201.

[0071] Referring to FIG. 2, the carrier 200 comprises the first composite layer 210 and the second composite layer 220 arranged along the first direction X, and the first composite layer 210 is connected to the second composite layer 220. The first direction X is the thickness direction of the carrier 200.

[0072] In some embodiments, the first composite layer 210 is provided with the opening 201, and the opening 201 penetrates through the first composite layer 210, and the opening 201 is configured to accommodate the insulation material.

[0073] In some embodiments, the first composite layer 210 comprises the first release layer 211, and the first release layer 211 is located at the outermost side of the first composite layer 210 along the first direction X and faces away from the second composite layer 220.

[0074] In some embodiments, the second composite layer 220 comprises the second release layer 221, and the second release layer 221 is connected to the first composite layer 210, and the second release layer 221 is exposed to the opening 201.

[0075] The adhesion between the insulating material in the injection part 1 and the carrier 200 is reduced by the first release layer 211, and the residual insulating material around the opening 201 is reduced. The insulating material is exposed to the opening 201 by the second release layer 221, so that the insulating part 100 is separated from the second release layer 221 after molding.

[0076] In some embodiments, the carrier 200 includes a plurality of openings 201 arranged along the second direction Y, and the second direction Y is perpendicular to the first direction X.

[0077] In some embodiments, the release force F1 of the first release layer 211 and the insulating material is 3g / 25mm≤F1≤300g / 25mm, so that the adhesion between the insulating material in the injection part 1 and the carrier 200 can be better reduced, and the residual insulating material around the opening 201 can be reduced.

[0078] Optionally, F1 can be any one or a range consisting of any two of 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, 20g / 25mm……297g / 25mm, 298g / 25mm, 299g / 25mm, 300g / 25mm.

[0079] In some embodiments, the first composite layer 210 includes a first base layer 212, the first release layer 211 is arranged along the first direction X with the first base layer 212, and the first base layer 212 is connected to the first release layer 211.

[0080] In some embodiments, along the first direction X, the thickness H1 of the first base layer 212 is 10μm≤H1≤200μm. By limiting 10μm≤H1≤200μm, the thickness of the insulating part 100 is limited, which facilitates the pasting of the insulating part 100 and reduces the space occupied by the insulating part 100.

[0081] Optionally, H1 can be any one or a range consisting of any two of 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm.

[0082] In some embodiments, 20 pm ≤ H1 ≤ 100 pm, further limiting the thickness of the insulating member 100, so as to facilitate better pasting of the insulating member 100 and reduce the space occupied by the insulating member 100.

[0083] In some embodiments, the material of the first release layer 211 includes silicone, reducing the adhesion of the insulating material to the first base layer 212, reducing the residual insulating material around the opening 201, and facilitating the scraping of the insulating material into the opening 201 by the glue injection member 1.

[0084] In some embodiments, the material of the first base layer 212 includes one or more of polyethylene terephthalate, polyimide, polytetrafluoroethylene, polyether ether ketone, polyphenylene sulfide, liquid crystal polymer, and polybenzimidazole.

[0085] In some embodiments, the first composite layer 210 includes a first glue layer 213 connecting the first base layer 212 and the second release layer 221. The adhesion F2 of the first glue layer 213 to the second release layer 221 satisfies 0.001 N / mm ≤ F2 ≤ 0.1 N / mm. If the adhesion is too small, the first base layer 212 and the second release layer 221 are easily separated in the case of scraping the insulating material, winding the carrier 200, etc. In the use of the insulating member 100, 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 is too large, the first base layer 212 and the second release layer 221 are not easily separated, affecting the pasting of the insulating member 100. By limiting 0.001 N / mm ≤ F2 ≤ 0.1 N / mm, the separation of the first base layer 212 and the second release layer 221 in the case of scraping the insulating material, winding the carrier 200, etc. can be reduced, and the first base layer 212 and the second release layer 221 are more easily separated when pasting the insulating member 100.

[0086] Optionally, F2 can be any one of 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, 0.08 N / mm, 0.085 N / mm, 0.09 N / mm, 0.095 N / mm, 0.1 N / mm or a range consisting of any two thereof.

[0087] In some embodiments, the thickness W of the first adhesive layer 213 is 3 μm≤W≤5 μm. 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 is affected. If the thickness of the first adhesive layer 213 is too large, the residual adhesive of the first adhesive layer 213 is likely to take the insulating member 100 away when separating the first base layer 212 and the second release layer 221. By limiting 3 μm≤W≤5 μm, the first base layer 212 and the second release layer 221 can be better connected, and the situation that the residual adhesive of the first adhesive layer 213 takes the insulating member 100 away is reduced.

[0088] Alternatively, W can 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, 5 μm or a range consisting of any two thereof.

[0089] In some embodiments, the release force F3 of the second release layer 221 to the insulating material is 50 g / 25 mm≤F3≤500 g / 25 mm. If the release force F3 is too small, the insulating member 100 is likely to be separated from the second release layer 221, and the insulating member 100 is likely 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 likely to pull the insulating member 100, causing the insulating member 100 to deform and affecting the pasting of the insulating member 100. By limiting 50 g / 25 mm≤F3≤150 g / 25 mm, the insulating member 100 can be better placed in the opening 201, and it is easy to separate the insulating member 100 from the second release layer 221 after the insulating member 100 is pasted.

[0090] Optionally, F3 can be any one or a range consisting of any two of 50g / 25mm, 52g / 25mm, 54g / 25mm, 56g / 25mm, 58g / 25mm, 60g / 25mm, 62g / 25mm, 64g / 25mm, 66g / 25mm, 68g / 25mm, 70g / 25mm, 72g / 25mm, 74g / 25mm, 76g / 25mm, 78g / 25mm, 80g / 25mm, 82g / 25mm, 84g / 25mm, 86g / 25mm, 88g / 25mm, 90g / 25mm, 92g / 25mm, 94g / 25mm, 96g / 25mm, 98g / 25mm, 100g / 25mm, 102g / 25mm, 104g / 25mm, 106g / 25mm, 108g / 25mm, 110g / 25mm, 112g / 25mm, 114g / 25mm, 116g / 25mm, 118g / 25mm, 120g / 25mm, 122g / 25mm, 124g / 25mm, 126g / 25mm, 128g / 25mm, 130g / 25mm, 132g / 25mm, 134g / 25mm, 136g / 25mm, 138g / 25mm, 140g / 25mm, 142g / 25mm, 144g / 25mm, 146g / 25mm, 148g / 25mm, 150g / 25mm, 151g / 25mm, …… 497g / 25mm, 498g / 25mm, 499g / 25mm, 500g / 25mm.

[0091] In some embodiments, the second composite layer 220 comprises a second base layer 222, the second base layer 222 is connected to the second release layer 221, the thickness H2 of the second base layer 222 along the first direction X is 30μm≤H2≤80μm. The carrier 200 is provided as a roll, the glue injection member 1 scrapes the insulating material into the opening 201 during the walking process, the second base layer 222 carries the insulating member 100, by limiting 30μm≤H2≤80μm, so as to reduce the case that the second base layer 222 is stretched and deformed during the walking process, reduce the influence on the forming of the insulating member 100, and facilitate cost control.

[0092] Optionally, H2 can be any one or a range consisting of any two 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, 80μm.

[0093] In some embodiments, the second base layer 222 has a thickness greater than that of the first base layer 212.

[0094] In some embodiments, the material of the second release layer 221 includes silicone, which is beneficial to reduce the adhesion between the insulating material and the second base layer 222, and facilitate separation of the insulating member 100.

[0095] In some embodiments, the material of the second base layer 222 includes one or more of polyethylene terephthalate, polyimide, polytetrafluoroethylene, polyether ether ketone, polyphenylene sulfide, liquid crystal polymer, and polybenzimidazole.

[0096] In some embodiments, the shape of the opening 201 includes any one of a triangle, a rectangle, a circle, an ellipse, and a special shape, as viewed along the first direction X.

[0097] In some embodiments, the opening 201 is formed by die cutting or laser etching.

[0098] In some embodiments, the insulating material is in a molten state when being scraped into the opening 201, and the melting point of the insulating material is less than that of the first base layer 212, which reduces the impact of temperature on the first base layer 212 and reduces the possibility of adhesion between the insulating material and the first base layer 212.

[0099] In some embodiments, the melting point of the insulating material is less than that of the second base layer 222, which reduces the impact of temperature on the second base layer 222, is beneficial to the second base layer 222 to bear the insulating member 100, and reduces deformation of the insulating member 100.

[0100] Referring to FIG. 5, an embodiment of the present application provides an electric core 300, which includes a first pole piece 310 and the insulating member 100 of any one of the above embodiments.

[0101] The electric core 300 includes an electric core shell 301, an electrode assembly (not shown in the figure), and an electrode terminal 302. The electrode assembly is arranged in the electric core shell 301, and the electrode terminal 302 is connected to the electrode assembly and extends out of the electric core shell 301.

[0102] In an embodiment, the electric core 300 includes two electrode terminals 302, and the two electrode terminals 302 have opposite polarities. Alternatively, the two electrode terminals 302 extend out of the electric core shell 301 from different sides. Alternatively, the two electrode terminals 302 extend out of the electric core shell 301 from the same side.

[0103] In some embodiments, the tensile strength P of the insulating member 100 is greater than or equal to 3 MPa, the surface of the insulating member 100 and the stress concentration area of the edge of the electrode terminal 302 are not easy to be cracked after the insulating member 100 is subjected to hot pressing, and the electric core 300 is not easy to be cracked after being subjected to aging tests such as cold and hot impact.

[0104] In some embodiments, the cold-heat shock test method: the battery cell 300 is kept in an environment of 85±3℃ for 30 minutes, and the temperature conversion time is less than or equal to 30 minutes; the battery cell 300 is kept in an environment of -40±3℃ for 30 minutes, and the temperature conversion time is less than or equal to 30 minutes; the above steps are repeated for 96 cycles.

[0105] In some embodiments, the electrode assembly includes the first tab 310, a second tab (not shown in the figure), and a separator film (not shown in the figure), the first tab 310, the separator film, and the second tab are sequentially stacked to form an electrode assembly unit, and a plurality of electrode assembly units are stacked to form the electrode assembly. In other embodiments, the electrode assembly has a winding structure, and the electrode assembly is formed by sequentially stacking and winding the first tab 310, the separator film, and the second tab.

[0106] Referring to FIG. 6, in some embodiments, the first tab 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 arranged at least on the second section 311b, insulating and protecting the second section 311b, and reducing the risk of the burr piercing the separator film and causing the second section 311b to contact the second tab and short circuit. The first direction X is the length direction or the width direction of the first tab 310.

[0107] In some embodiments, part of the insulating member 100 covers the second section 311b, and part of the insulating member 100 is connected to the side of the active material layer 312 away from the current collector 311, further reducing the risk of short circuit.

[0108] In some embodiments, along a second direction Y, at least part of the second section 311b is arranged between two insulating members 100.

[0109] In an embodiment, the active material layer 312 is coated on the first section 311a by extrusion coating, transfer coating, spray coating, or the like.

[0110] Referring to FIG. 7, in some embodiments, the current collector 311 includes a third section 311c connected to the second section 311b. The battery cell 300 includes an electrical connection member 320 arranged on the third section 311c, and the insulating member 100 covers part of the electrical connection member 320, insulating and protecting the electrical connection member 320.

[0111] 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 connection member 320, so that the second section 311b is covered by the insulating member 100, facilitating insulation.

[0112] In some embodiments, the width d1 of the insulation member 100 overlapping the active material layer 312 along the first direction X is 0.1 mm≤d1≤2 mm.

[0113] In an embodiment, the electrical connector 320 is welded to the third section 311c and forms a welding area 320a. The insulation 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.

[0114] In some embodiments, the welding area 320a includes a welding spot 3201, and the insulation member 100 covers the welding spot 3201 to reduce the risk of the welding spot 3201 piercing the separator.

[0115] 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 insulation member 100 can wrap the burr of the electrical connector 320 to reduce the risk of the burr piercing the separator.

[0116] In some embodiments, the first tab 310 includes a primer layer 313 disposed on the second section 311b to reduce the risk of the burr piercing the separator and causing the second section 311b to contact the second tab. The insulation member 100 connects the primer layer 313 and the electrical connector 320 to further reduce the risk of the burr piercing the separator.

[0117] Referring to FIG. 8, in some embodiments, the insulation member 100 has a gap d2 of 0 mm≤d2≤0.7 mm with the active material layer 312 along the first direction X.

[0118] Optionally, d2 can be any one of 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm or a range formed by any two of them.

[0119] In some embodiments, the current collector 311 includes a polymer layer (not shown) and two metal layers (not shown), and the polymer layer is between the two metal layers. The active material layer 312 is disposed on the surface of the metal layer.

[0120] In some embodiments, the electrical connector 320 is connected to the metal layer.

[0121] Referring to FIG. 9, in some embodiments, the battery cell 300 includes at least two insulation members 100, and the electrical connector 320 is between the two insulation members 100 along the second direction Y.

[0122] In some embodiments, the insulation member 100 includes a first area 110 extending out of the third section 311c along the first direction X along the second direction Y.

[0123] In some embodiments, the first region 110 comprises a first sub-region 110a, a projection of the first sub-region 110a along the second direction Y is separated from or does not overlap with a projection of the electrical connector 320. Two first sub-regions 110a of two adjacent insulating pieces 100 are connected along the second direction Y. By connecting the two first sub-regions 110a, the overmolded electrical connector 320 covers two sides of the electrical connector 320 along the third direction Z, reducing the risk of the burr 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.

[0124] In some embodiments, when the battery cell 300 is at a high temperature, the isolation film is heated and shrinks, and the risk of the burr or the welding mark 3201 on the first electrode tab 310 contacting the second electrode tab due to the shrinkage of the isolation film is reduced by the insulating piece 100.

[0125] In some embodiments, the adhesion F between the insulating piece 100 and the electrical connector 320 is F≥0.08 N / mm, which is beneficial to reduce the risk of the insulating piece 100 detaching and causing the first electrode tab 310 and the second electrode tab to short circuit.

[0126] In some embodiments, after the insulating piece 100 is soaked in a 85℃ DMC solution for 24 hours, the adhesion F between the insulating piece 100 and the electrical connector 320 is F≥0.06 N / mm, which is beneficial to reduce the risk of the insulating piece 100 detaching and causing the first electrode tab 310 and the second electrode tab to short circuit during long-term cyclic use of the battery cell.

[0127] The application will be further described below through specific embodiments.

[0128] 100 insulating pieces 100 were produced with different viscosities of the material and mass proportions of the inorganic filler, and the number of formed insulating pieces 100 was recorded.

[0129] The tensile strength of the formed insulating pieces 100 was tested. The tensile strength test method was as follows: the two ends of the insulating piece 100 were clamped by a tensile testing machine, the insulating piece 100 was stretched until it broke, the stretching speed was 50 mm / min, the width of the test sample was 3 mm, and the tensile strength of the insulating piece 100 in the corresponding embodiment was recorded.

[0130] The viscosity test method was as follows: 10-11 g of the insulating piece 100 was weighed, the insulating piece 100 was placed in an aluminum tank of a rotary viscometer, the speed of the rotary viscometer equipment was adjusted to 12 RPM, the aluminum tank was placed in a heating furnace and covered with a heat insulation cap, heated to 190℃, and kept for 10 minutes, and the viscosity of the insulating piece was detected using a SC4-27 type rotor.

[0131] Table 1

[0132] From the examples 1 to 5 in Table 1, it can be known that the insulation piece 100 has a viscosity in the range of 1000cps to 5000cps after melting when heated to 190℃, the insulation piece 100 is easier to shape, and is beneficial to production.

[0133] From the examples 8 to 11, it can be known that the addition ratio of the inorganic filler in the range of 5% to 10% is beneficial to improve the tensile strength P of the insulation piece 100, easy to shape the insulation piece 100 and the insulation piece 100 is not easy to crack, which is beneficial to insulation.

[0134] From the comparative example 1 and the examples 1 to 5, it can be known that when the tensile strength P of the insulation piece is P≥3MPa, the insulation piece 100 is not easy to be deformed or broken in use, which is beneficial to insulation.

[0135] Referring to FIG. 10, the application also provides a manufacturing method of the battery cell 300, comprising the following steps:

[0136] Step 1: forming the first pole piece 310 by coating, cold pressing and slicing;

[0137] Step 2: bonding the insulation piece 100 to the second section 311b;

[0138] Step 3: separating the second release layer 221 and the insulation piece 100.

[0139] In some embodiments, step 1 specifically comprises uniformly coating the prepared slurry on the pretreated current collector 311, roll pressing the dried pole piece, and slicing the pole piece according to the size to form the first pole piece 310.

[0140] In some embodiments, step 2 specifically comprises peeling off the first release layer 211 to expose the insulation piece 100, and bonding the insulation piece 100 to the second section 311b by hot pressing the second release layer 221 to activate the adhesion of the insulation piece 100.

[0141] In some embodiments, the adhesion activation temperature T of the insulation piece 100 is 60℃≤T≤100℃.

[0142] Alternatively, T can be any one of 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃, 100℃ or a range formed by any two of them.

[0143] In some embodiments, the pressure F4 of hot pressing the second release layer 221 is 0.05Mpa≤F4≤0.6Mpa.

[0144] Optionally, F4 can be any one or a range consisting of any two 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, 0.6 MPa.

[0145] In some embodiments, between step 1 and step 2, the following step is included: welding two electrical connectors 320 to both sides of the third section 311c, and forming a welding mark 3201. The insulation member 100 covers the welding mark 3201.

[0146] Referring to FIG. 11, the application also provides a power consuming device 400 using the above-mentioned battery cell 300.

[0147] In an embodiment, the power consuming device 400 of the application can be, but is not limited to, an electronic device, a drone, a backup power supply, an electric vehicle, an electric motorcycle, an electric power-assisted bicycle, an electric tool, a household large storage battery, etc.

[0148] Those skilled in the art should recognize that the above embodiments are only used to illustrate the application, and are not used as a limitation to the application. Any appropriate changes and variations to the above embodiments, as long as they fall within the spirit and scope of the application, are within the scope of the disclosure.

Claims

1. An insulating member, characterized by, The insulating piece is configured to be heated to 190 DEG C, and to be molten for 10 minutes, and the viscosity of the molten insulating piece is 1000cps to 5000cps.

2. The insulator of claim 1, wherein The tensile strength P of the insulating piece is P >= 3MPa.

3. The insulator of claim 1, wherein The material of the insulating piece comprises one or more of modified polypropylene, modified polyethylene, modified ethylene elastomer, modified propylene elastomer, modified styrene elastomer, modified ionomer resin, modified polyvinylidene fluoride, modified polyvinylidene fluoride-hexafluoropropylene copolymer, modified polymethyl methacrylate and modified polyethylene glycol.

4. The insulator of claim 3, wherein The material used for modification comprises one or more of maleic acid, acrylic acid, methacrylic acid, maleic anhydride and epoxy group.

5. The insulator of claim 1, wherein, The insulating piece comprises inorganic fillers, and the inorganic fillers comprise one or more of boehmite, silica, calcium carbonate, talc powder, wollastonite, quartz powder, aluminum hydroxide, mica powder, titanium white powder and glass fiber.

6. The insulator of claim 5, wherein The mass percentage of the inorganic fillers in the total mass of the insulating piece is 5% to 10%.

7. The insulator of claim 1, wherein The thickness d of the insulating piece is 10um <= d <= 200um.

8. The insulator of claim 7, wherein, The thickness d of the insulating piece is 10um <= d <= 50um.

9. The insulator of claim 1, wherein, The melting point T of the insulating piece is 100 DEG C <= T <= 200 DEG C.

10. The insulator of claim 1, wherein, The viscosity is tested by taking 10-11g of the insulating piece, placing the insulating piece into an aluminum tank of a rotary viscometer, adjusting the rotating speed of the rotary viscometer equipment to 12RPM, placing the aluminum tank into a heating furnace and covering it with a heat insulation cap to heat to 190 DEG C for 10 minutes, and using a SC4-27 type rotor for detection.

11. An electric cell characterized by The insulating piece comprises a first pole piece and the insulating piece as claimed in any one of claims 1 to 10. 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, and the active material layer is arranged on a surface of the first section. The insulating piece is arranged at least on the second section, and the first direction is a length direction or a width direction of the first pole piece.

12. The cell of claim 11, wherein, The electric core comprises an electrical connection piece, the current collector comprises a third section, the third section is connected to the second section, the electrical connection piece is arranged on the third section, and the insulating piece covers part of the electrical connection piece.

13. The electrically charged cell of claim 12, wherein, Along the first direction, a width d1 of the insulating piece overlapping the active material layer is 0.1mm <= d1 <= 2mm.

14. The cell of claim 12, wherein, The electrical connection piece is welded to the third section, and forms a welding area, and the insulating piece covers the welding area.

15. The cell of claim 14, wherein, The electric core comprises at least two insulating pieces, and along a second direction, the electrical connection piece is located between the two insulating pieces, and the second direction is a thickness direction of the electric core. Along the first direction, the insulating piece comprises a first area, and the first area extends out of the third section along the first direction. The first area comprises a first sub-area, and along the second direction, a projection of the first sub-area is separated from a projection of the electrical connection piece. Along the second direction, first sub-areas of two adjacent insulating pieces are connected.

16. The electrically charged cell of claim 15, wherein, Along the second direction, at least part of the second section is arranged between the two insulating pieces.

17. The electrically charged cell of claim 12, wherein, The adhesion force F between the insulating member and the electrical connecting member is greater than or equal to 0.08 N / mm.

18. The electrically charged cell of claim 12, wherein, The current collector comprises a polymer layer and two metal layers, the polymer layer is between the two metal layers, and the active material layer is arranged on the surface of the metal layer.

19. The electrically charged cell of claim 12, wherein, The first pole piece comprises a base coating layer, the base coating layer is arranged on the second section, the insulating member connects the base coating layer and the electrical connecting member along the second direction, and the second direction is the thickness direction of the battery cell.

20. The electrically charged cell of claim 11, wherein, Along the first direction, the insulating member has a gap d2 with the active material layer, and 0 mm≤d2≤0.7 mm.

21. The electrically charged cell of claim 12, wherein, After the first pole piece with the insulating member is soaked in a DMC solution at 85°C for 24 hours, the adhesion force F between the insulating member and the electrical connecting member is greater than or equal to 0.06 N / mm.

22. The electrically charged cell of claim 12, wherein, The insulating member is attached to the second section.

23. A method of manufacturing an electrical cell as claimed in any one of claims 11 to 22, wherein the insulating member is provided on the carrier, characterized in that, The method comprises the following steps: 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 of claim 23, wherein the step of forming the electrode assembly comprises the step of: Between the step 1 and the step 2, the following step is included: welding two electrical connecting members on both sides of the third section to form the welding area, and the insulating member covers the welding area. ​ 25. An electrical device, comprising: The battery cell comprises any one of claims 11 to 22.

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