WO2021155852A1 - 负极极片、应用所述负极极片的电池以及电子装置 - Google Patents

负极极片、应用所述负极极片的电池以及电子装置 Download PDF

Info

Publication number
WO2021155852A1
WO2021155852A1 PCT/CN2021/075641 CN2021075641W WO2021155852A1 WO 2021155852 A1 WO2021155852 A1 WO 2021155852A1 CN 2021075641 W CN2021075641 W CN 2021075641W WO 2021155852 A1 WO2021155852 A1 WO 2021155852A1
Authority
WO
WIPO (PCT)
Prior art keywords
pole piece
fiber
fiber coating
negative electrode
battery
Prior art date
Application number
PCT/CN2021/075641
Other languages
English (en)
French (fr)
Inventor
崔伟
Original Assignee
宁德新能源科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 宁德新能源科技有限公司 filed Critical 宁德新能源科技有限公司
Publication of WO2021155852A1 publication Critical patent/WO2021155852A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2200/00—Safety devices for primary or secondary batteries
    • H01M2200/30—Preventing polarity reversal
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • This application relates to the field of batteries, and in particular to a negative pole piece, a battery using the negative pole piece, and an electronic device including the battery.
  • lithium-ion batteries Due to its own characteristics, lithium-ion batteries are prone to internal short-circuits and thermal runaway when subjected to abnormal conditions such as puncture, extrusion, and high temperature, which may cause the battery to catch fire or even explode.
  • the thermal runaway of lithium-ion batteries is usually caused by the instability of the negative electrode (anode).
  • the battery When the battery short-circuits the positive and negative electrodes under abnormal conditions, it will release heat, especially the positive current collector aluminum foil and negative pole pieces. Because of its low contact resistance, it releases more heat, which triggers a chain reaction of the negative electrode, which in turn releases more heat, causing thermal runaway, causing the battery to catch fire or even explode.
  • the isolation film is likely to cause a short circuit between the positive and negative electrodes due to thermal shrinkage, resulting in fire or even explosion.
  • This application provides a negative pole piece, including a pole piece substrate and a fiber coating.
  • the pole piece base includes a negative electrode current collector and a negative electrode active layer arranged on the surface of the negative electrode current collector.
  • the fiber coating is arranged on the surface of the pole piece substrate, and the fiber coating has a porous structure. Among them, based on the total mass of the fiber coating, the fiber coating includes 90% to 100% fiber, 0% to 8% binder, and 0% to 2% thickener in terms of mass percentage.
  • the fiber is selected from at least one of carboxymethyl cellulose, polyester fiber and polysulfone fiber
  • the binder is selected from styrene-butadiene rubber, polyacrylate, polyacrylic acid, sodium carboxymethyl cellulose, and carboxymethyl cellulose.
  • the aspect ratio of each fiber is 20 to 5000, wherein the length of each fiber is 10 ⁇ m to 50 ⁇ m, and the diameter of each fiber is 0.01 ⁇ m to 0.5 ⁇ m.
  • the melting point of each fiber is greater than or equal to 200°C.
  • the thickness of the fiber coating is 0.1 ⁇ m to 10 ⁇ m.
  • the thickness of the fiber coating is 0.5 ⁇ m to 5 ⁇ m.
  • the porosity of the fiber coating is 20% to 70%.
  • the bonding force between the fiber coating and the pole piece substrate is greater than or equal to 5 N/m.
  • the area of the pole piece substrate covered by the fiber coating accounts for 50% or more of the surface of the pole piece substrate, and the surface of the pole piece substrate refers to the surface area of a single side of the pole piece substrate.
  • the application also provides a battery, which includes a positive pole piece, a separator, and the negative pole piece as described above, and the separator is disposed between the positive pole piece and the negative pole piece.
  • the bonding force between the fiber coating and the isolation membrane is greater than or equal to 5 N/m.
  • the present application also provides an electronic device, including the battery as described above.
  • the fiber coating in the negative pole piece in this application has a porous structure, which has the characteristics of high strength, good toughness and good heat resistance, which is beneficial to protect the pole piece substrate and can effectively prevent the positive and negative poles from short-circuiting. Occurrence, such as preventing the short circuit of the positive and negative electrodes caused by puncture, extrusion, and the short circuit of the positive and negative electrodes caused by the failure of the high-temperature separator, thereby reducing the probability of short circuits and improving the safety of the battery.
  • due to the porous structure and specific content composition of the fiber coating it does not block the transmission of lithium ions and electrolyte, ensuring the normal use of the battery.
  • FIG. 1 is a schematic diagram of the structure of a negative pole piece according to an embodiment of the application.
  • Fig. 2 is a scanning electron microscope (SEM) image of a fiber coating according to an embodiment of the application.
  • Fig. 3 is an SEM image of the fiber coating shown in Fig. 2 at another magnification.
  • FIG. 4 is a schematic diagram of the structure of a battery cell according to an embodiment of the application.
  • an embodiment of the present application provides a negative pole piece 100, which includes a pole piece base 10 and a fiber coating 30 disposed on the surface of the pole piece base 10.
  • the pole piece base 10 includes a negative electrode current collector 11 and a negative electrode active layer 15 disposed on the negative electrode current collector 11.
  • the fiber coating 30 is disposed on the surface of the negative electrode active layer 15 away from the negative electrode current collector 11.
  • the fiber coating 30 has a porous structure.
  • the fiber coating 30 contains 90% to 100% fiber, 0% to 8% binder, and 0% to 2% thickener based on the total mass of the fiber coating 30 in terms of mass percentage.
  • the porous structure of the fiber coating makes the fiber coating 30 high in strength and toughness, which is beneficial to protect the pole piece substrate.
  • the thickness of the fiber coating 30 is 0.1 ⁇ m to 10 ⁇ m.
  • the thickness of the fiber coating 30 is 0.5 ⁇ m to 5 ⁇ m.
  • the porosity of the fiber coating 30 is 20% to 70%.
  • the electrolyte needs to pass through the fiber coating 30 and then contact the pole piece substrate 10, and lithium ions need to pass through the fiber coating 30 for transmission between the positive and negative electrodes. Therefore, The higher the porosity of the fiber coating 30 is, the faster the electrolyte can infiltrate the pole piece substrate 10 and the lower the transmission resistance of lithium ions.
  • the porosity of the fiber coating 30 is too high, the strength of the fiber coating 30 will be insufficient to prevent the burr of the aluminum foil from passing through the pores of the fiber coating 30 to contact the pole piece substrate 10, so that the fiber coating 30 is opposite to the pole.
  • the protective effect of the sheet substrate 10 is weakened.
  • the area of the pole piece substrate 10 covered by the fiber coating 30 accounts for 50% or more of the surface area of the pole piece substrate 10 (in this application, the above-mentioned proportion is referred to as the coverage of the fiber coating). If the area of the pole piece base body 10 covered by the fiber coating 30 is too small on the surface of the pole piece base body 10, the puncture process is likely to cause a short circuit of the positive and negative electrodes.
  • the bonding force between the fiber coating 30 and the pole piece base 10 is greater than or equal to 5 N/m, so as to prevent the fiber coating 30 from falling off the pole piece base 10.
  • the fiber has a relatively high melting point and is non-conductive, and can be selected from but not limited to at least one of carboxymethyl cellulose fiber, polyester fiber, and polysulfone fiber.
  • the chemical stability and electrochemical stability of the fiber are good.
  • the aspect ratio of each fiber is 20 to 5000.
  • the length of each fiber is 10 ⁇ m to 50 ⁇ m to facilitate the overlap between the fibers to form a film layer, and the diameter of each fiber is 0.01 ⁇ m to 0.5 ⁇ m.
  • the slurry forming the fiber coating will easily block the filter screen during filtration, and easily block the micropores of the gravure roll during coating; while the aspect ratio is too small, the length of the fiber will be short, and the raw material itself The processing is difficult, and it is not conducive to the formation of a complete coverage network, that is, it is not conducive to the lap between the fibers to form a film layer.
  • the melting point of each fiber is greater than or equal to 200° C., so that the fiber coating 30 has better heat resistance, which is beneficial to protect the pole piece substrate under high temperature conditions.
  • the binder may be selected from but not limited to at least one of styrene butadiene rubber, polyacrylate, polyacrylic acid, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyvinylidene fluoride, or polyethylene glycol.
  • sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyacrylic acid, and polyethanol can also be used as thickeners in fiber coatings.
  • the slurry for forming the fiber coating can be applied to the surface of the pole piece base 10 by means of extrusion, transfer, printing, spraying, etc., and then dried to form the fiber coating 30.
  • the solvent for forming the fiber coating slurry can be selected from but not limited to water (such as deionized water), N-methylpyrrolidone, N,N-dimethylformamide and N,N-dimethylacetamide Wait.
  • the above-mentioned negative pole piece 100 is applied to a battery.
  • the battery further includes a positive pole piece 200 and a separator 300.
  • the isolation film 300 is disposed between the positive pole piece 200 and the negative pole piece 100.
  • the negative pole piece 100, the separator 300, and the positive pole piece 200 may constitute a stacked cell (ie, a laminated cell) or a wound cell.
  • the bonding force between the fiber coating 30 and the isolation film 300 is greater than or equal to 5 N/m, so as to avoid the misalignment of the negative pole piece 100 and the isolation film 300 under the action of external force (for example, impact) and cause short circuit of the battery. Further improve the safety of the battery.
  • the above-mentioned battery can be applied to an electronic device.
  • Electronic devices can be, but are not limited to, mobile phones, computers, toys, etc.
  • the aluminum foil is used as the positive electrode current collector, and the positive electrode active slurry is uniformly coated on the surface of the aluminum foil, and then the positive electrode active layer is formed by cold pressing, thereby preparing the positive pole piece.
  • the positive electrode active slurry is composed of 97.8 wt% of LiCoO 2 (LCO, positive electrode active material), 0.8 wt% of polyvinylidene fluoride (PVDF), and 1.4 wt% of conductive carbon black.
  • the preparation of the negative electrode piece the copper foil is used as the negative electrode current collector, and the negative electrode active slurry is uniformly coated on the surface of the copper foil, and then the negative electrode active layer is formed by cold pressing, thereby preparing the negative electrode piece.
  • the negative active slurry is composed of 97.7 wt% of artificial graphite, 1.3 wt% of carboxymethyl cellulose (CMC), and 1.0 wt% of styrene butadiene rubber (SBR).
  • the thickness of the negative electrode active layer is 200 ⁇ m.
  • the preparation of the battery the above-mentioned positive pole piece and the above-mentioned negative pole piece are wound, wherein the positive pole piece and the negative pole piece are separated by a polyethylene (PE) film as a separator, and then a wound battery cell is prepared ;
  • the winding cell is sealed on the top side, coded, vacuum dried, injected with electrolyte, left standing at a high temperature, and then subjected to formation and capacity testing to obtain a battery.
  • PE polyethylene
  • Comparative Example 2 The difference between Comparative Example 2 and Comparative Example 1 lies in the preparation of the negative pole piece.
  • the preparation of the negative pole piece is: using copper foil as the negative electrode current collector, uniformly coating the negative electrode active slurry on the surface of the copper foil, and then cold pressing to form the negative electrode active layer, thereby preparing the pole piece substrate; wherein, the negative electrode active slurry is made of It is composed of 97.7 wt% of artificial graphite, 1.3 wt% of carboxymethyl cellulose (CMC) and 1.0 wt% of styrene butadiene rubber (SBR), and the thickness of the negative electrode active layer is 200 ⁇ m.
  • CMC carboxymethyl cellulose
  • SBR styrene butadiene rubber
  • the fiber slurry is prepared by dissolving fibers, binders and thickeners in deionized water and dispersing them at a constant speed. Among them, the solid content of the fiber slurry is 10%.
  • the fiber, binder and thickener are 85% carboxymethyl cellulose fiber, 10% styrene butadiene rubber emulsion and 5% carboxymethyl cellulose in terms of mass percentage.
  • the aspect ratio of the fiber is 500.
  • the thickness of the fiber coating is 0.5 ⁇ m, the porosity is 70%, and the coverage is 90%.
  • Comparative Example 3 The difference between Comparative Example 3 and Comparative Example 2 is that the fiber, binder and thickener are 97% carboxymethyl cellulose fiber, 2% styrene butadiene rubber emulsion and 1% carboxymethyl cellulose by mass percentage. ; The coverage of fiber coating is 45%.
  • Example 1 The difference between Example 1 and Comparative Example 1 lies in the preparation of the negative pole piece.
  • the preparation of the negative pole piece is: using copper foil as the negative electrode current collector, uniformly coating the negative electrode active slurry on the surface of the copper foil, and then cold pressing to form the negative electrode active layer, thereby preparing the pole piece substrate; wherein, the negative electrode active slurry is made of It is composed of 97.7 wt% of artificial graphite, 1.3 wt% of sodium carboxymethyl cellulose (CMC) and 1.0 wt% of styrene butadiene rubber (SBR), and the thickness of the negative active layer is 200 ⁇ m.
  • the surface of the pole piece base is coated with fiber slurry and dried to form a fiber coating, and then a negative pole piece is prepared.
  • the fiber slurry is prepared by dissolving fibers, binders and thickeners in deionized water and dispersing them at a constant speed. Among them, the solid content of the fiber slurry is 10%.
  • the fiber, binder and thickener are 97% carboxymethyl cellulose fiber, 2% styrene-butadiene rubber emulsion and 1% carboxymethyl cellulose by mass percentage.
  • the aspect ratio of the fiber is 500.
  • the thickness of the fiber coating is 0.5 ⁇ m, the porosity is 70%, and the coverage is 90%.
  • Example 2 The difference between Example 2 and Example 1 is that the thickness of the fiber coating is 5 ⁇ m.
  • Example 3 The difference between Example 3 and Example 1 is that the thickness of the fiber coating is 3 ⁇ m.
  • Example 4 The difference between Example 4 and Example 3 is that the aspect ratio of the fiber is 300.
  • Example 5 The difference between Example 5 and Example 3 is that the fibers are polysulfone fibers.
  • Example 6 The difference between Example 6 and Example 3 is that the fiber coating contains 90% carboxymethyl cellulose fiber, 9% styrene butadiene rubber emulsion, and 1% carboxymethyl cellulose in terms of mass percentage.
  • Example 7 The difference between Example 7 and Example 2 is that the fiber coating contains 100% carboxymethyl cellulose fiber in terms of mass percentage.
  • Example 8 contains 97% polyester fiber, 2% polyacrylate emulsion, and 1% lithium carboxymethyl cellulose in terms of mass percentage.
  • Example 9 The difference between Example 9 and Example 3 is that the aspect ratio of the fiber is 20.
  • Example 10 The difference between Example 10 and Example 3 is that the aspect ratio of the fiber is 5000.
  • Example 11 The difference between Example 11 and Example 3 is that the aspect ratio of the fiber is 250.
  • Example 12 contains 97% polyester fiber, 2% styrene butadiene rubber emulsion, and 1% polyacrylic acid in terms of mass percentage; the fiber aspect ratio is 300.
  • Example 13 The difference between Example 13 and Example 3 is that the porosity of the fiber coating is 20%.
  • Example 14 The difference between Example 14 and Example 3 is that the fiber coating contains 97% carboxymethyl cellulose fiber, 2% polyacrylate emulsion, and 1% polyacrylic acid in terms of mass percentage.
  • Example 15 The difference between Example 15 and Example 3 is that the porosity of the fiber coating is 45%.
  • Example 16 The difference between Example 16 and Example 3 is that the porosity of the fiber coating is 60%.
  • Example 17 contains 98.5% carboxymethyl cellulose fiber, 0.5% styrene butadiene rubber emulsion, and 1% carboxymethyl cellulose in terms of mass percentage.
  • Example 18 contains 95% carboxymethyl cellulose fiber, 4% styrene butadiene rubber emulsion, and 1% carboxymethyl cellulose in terms of mass percentage.
  • Example 19 The difference between Example 19 and Example 3 is that the coverage rate of the fiber coating is 50%.
  • Example 20 The difference between Example 20 and Example 3 is that the coverage rate of the fiber coating is 100%.
  • Example 21 contains 97% carboxymethyl cellulose fiber, 2% polyvinylidene fluoride powder, and 1% polyvinyl alcohol in terms of mass percentage.
  • Example 22 The difference between Example 22 and Example 1 is that the thickness of the fiber coating is 0.1 ⁇ m, and the aspect ratio of the fiber is 350.
  • Example 23 The difference between Example 23 and Example 1 is that the thickness of the fiber coating is 10 ⁇ m.
  • the method for measuring the above battery capacity is: stand for 30min in an environment of 25 ⁇ 3°C, charge at a constant current of 0.5C (1C is the rated capacity of the battery) until the battery voltage reaches 4.4V (rated voltage), and then transfer to constant voltage charging , Stop charging when the current reaches 0.05C; let the battery stand for 30min; then discharge the battery to 3.0V with a current of 0.2C and let it stand for 30min; take the discharge capacity as the actual capacity of the battery.
  • the method for measuring the nail penetration performance of the above battery is as follows: Take 10 batteries in each comparative example or embodiment, and fully charge them in an environment of 25 ⁇ 3°C, specifically, charge with 0.5C current and constant current to 4.4V, and constant voltage. Charging to 0.05C current cut-off. Each battery is nailed under normal temperature conditions, the nailing speed is set to 30mm/s, and the nailing depth is subject to the taper of the steel nail passing through the battery. If the battery does not fire or explode after nail penetration, the battery passes the nail penetration test, otherwise, it fails. In this way, count the number of batteries that have passed the nail penetration test among the 10 batteries.
  • steel nails with a diameter of 4mm are used for nailing, the material is carbon steel, the taper is 16.5mm, and the total length of the steel nails is 100mm.
  • the penetration of the battery in each comparative example or example was detected and recorded in Table 1 below.
  • the method for measuring the discharge rate performance of the above battery is as follows: after the battery is allowed to stand in an environment of 25°C ⁇ 3°C for 30 minutes, it is charged to 4.4V with a constant current of 0.5C, and then charged to a current cut-off of 0.05C at a constant voltage; the battery is left for 30min; Discharge at a constant current of 0.2C to 3.0V to obtain the discharge capacity C1; leave the battery for 30min; then charge at a constant current of 0.5C to 4.4V, then charge at a constant voltage to 0.05C, the current cut-off; leave the battery for 30min; then use a constant current of 2.0C Discharge to 3.0V to obtain the discharge capacity C2, C2/C1 is the discharge rate of the battery at 2C. Specific data are recorded in Table 1 and Table 2 below.
  • the binding force between the fiber coating in the negative pole piece and the corresponding pole piece substrate in Example 1-23 was measured, and the specific method was: the negative pole piece was pasted on a smooth steel plate through double-sided tape, and the negative electrode Stick a piece of adhesive paper on the surface of the sheet away from the steel plate, and fix one end of the adhesive paper on the tensile machine, pull the adhesive paper through the tensile machine, read the adhesive force of the adhesive paper when it is stretched, and divide the read adhesive force by the adhesive The width of the paper can obtain the bonding force between the fiber coating and the pole piece substrate. Specific data are recorded in Table 1 below.
  • the binding force between the fiber coating in the negative pole piece and the corresponding separator in Example 1-23 was measured, and the specific method was as follows: the negative pole piece and the separator were laminated together under the conditions of 85°C and -1MPa Under heat press for 2 minutes, the separator is bonded to the fiber coating.
  • the length of the separator is longer than the length of the negative pole piece so that the separator extends from one end of the negative pole piece, and the part of the separator that extends from the negative pole piece is fixed on
  • pull the isolating film through the tensile machine read the adhesive force of the isolating film when it is stretched, and divide the read adhesive force by the width of the isolating film to obtain the adhesion between the fiber coating and the isolating film force.
  • Extrusion test and hot box test were performed on Comparative Example 1, Comparative Example 3 and Examples 1-23, respectively.
  • the specific operations of the measurement method of the extrusion test and the measurement method of the hot box test are as follows.
  • the measurement method of the squeeze test Fully charge at a certain current to the full charge voltage of the battery cell, and then charge at a constant voltage to a certain current under the full charge voltage (for example: fully charge to 4.45V at a constant current of 0.5C, and then charge at 4.45V. Press down and charge until the current reaches 0.025C); take a picture before the test, then use an 8mm square pressure rod to squeeze the cell head with a pressure of 13.0kN for testing, and take a picture after the test. If the battery does not explode and does not catch fire, the battery passes the squeeze test, otherwise, it fails. In this way, count the number of batteries that passed the squeeze test among the 10 batteries and record them in Table 1 below.
  • the measurement method of the hot box test Fully charge at a certain current to the full charge voltage of the battery cell, and then charge at a constant voltage to a certain current under the full charge voltage (for example: fully charge to 4.45V at a constant current of 0.5C, and then charge at 4.45V. Charge under pressure until the current reaches 0.025C); let stand at 25 ⁇ 5°C for 60min, check the appearance and take pictures before testing, and then increase to 120°C ⁇ 2°C, 130 at a rate of 5°C/min ⁇ 2°C/min. °C ⁇ 2 °C, 135 °C ⁇ 2 °C, 140 °C ⁇ 2 °C, and then keep for 30 minutes to test, and after the test, check the appearance and take pictures. If the battery does not explode and does not catch fire, the battery passes the hot box test, otherwise, it fails. In this way, count the number of batteries that have passed the hot box test among the 10 batteries and record them in Table 1 below.
  • the fiber coating in the negative pole piece in this application has a porous structure, which has the characteristics of high strength, good toughness and good heat resistance, which is beneficial to protect the pole piece substrate and can effectively prevent the occurrence of short-circuit between the positive and negative electrodes. For example, it can prevent the short circuit of the positive and negative electrodes caused by puncture, extrusion, and the short circuit of the positive and negative electrodes caused by the failure of the high-temperature separator, thereby reducing the probability of short circuits and improving the safety of the battery. In addition, due to the porous structure and specific content composition of the fiber coating, it does not block the transmission of lithium ions and electrolyte, ensuring the normal use of the battery.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Cell Separators (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

一种负极极片，包括极片基体及纤维涂层。所述极片基体包括负极集流体以及设置于所述负极集流体的表面的负极活性层；所述纤维涂层设置于所述极片基体的表面，所述纤维涂层为多孔结构；其中，以质量百分比计，所述纤维涂层中包括90％～100％的纤维、0％～8％的粘结剂以及0％～2％的增稠剂。本申请还提供一种应用上述负极极片的电池及包括上述电池的电子装置，所述负极极片有利于提高电池的安全性。

Description

负极极片、应用所述负极极片的电池以及电子装置 技术领域
本申请涉及电池领域，尤其涉及一种负极极片、应用所述负极极片的电池以及包括所述电池的电子装置。
背景技术
锂离子电池由于其本身的特性，在受到穿刺、挤压、高温等异常工况时，极易发生内部短路而引发热失控，从而造成电池的起火甚至爆炸。研究显示，锂离子电池的热失控通常是由于负极(阳极)的不稳定性造成的，当电池在异常工况下发生正负极短路时会放出热量，尤其是正极集流体铝箔和负极极片的接触，由于其接触电阻小，因此所释放的热量更多，从而引发负极发生连锁反应，进而放出更多的热量，从而发生热失控，造成电池的起火甚至爆炸。另外当电池处在高温环境中(>130℃时)，隔离膜由于热收缩进而容易导致正负极接触短路从而发生起火甚至爆炸。
发明内容
鉴于上述情况，有必要提供一种提高安全性的负极极片以及应用所述负极极片的电池和应用所述电池的电子装置。
本申请提供了一种负极极片，包括、极片基体及纤维涂层。极片基体包括负极集流体以及设置于负极集流体的表面的负极活性层。纤维涂层设置于所述极片基体的表面，纤维涂层为多孔结构。其中，基于纤维涂层的总质量，以质量百分比计，纤维涂层中包括90％至100％的纤维、0％至8％的粘结剂以及0％至2％的增稠剂。
进一步的，纤维选自羧甲基纤维素、聚酯纤维以及聚砜类纤维中的至少一种，粘结剂选自丁苯橡胶、聚丙烯酸酯、聚丙烯酸、羧甲基纤维素钠、羧 甲基纤维素锂、聚偏氟乙烯以及聚乙二醇中的至少一种。
进一步的，每一纤维的长径比为20至5000，其中，每一纤维的长度为10μm至50μm，每一纤维的直径为0.01μm至0.5μm。
进一步的，每一纤维的熔点大于或者等于200℃。
进一步的，纤维涂层的厚度为0.1μm至10μm。
进一步的，纤维涂层的厚度为0.5μm至5μm。
进一步的，纤维涂层的孔隙率为20％至70％。
进一步的，纤维涂层与极片基体之间的粘结力大于或等于5N/m。
进一步的，极片基体被纤维涂层覆盖的面积占极片基体表面的50％及其以上，极片基体表面指的是极片基体单面的表面积。
本申请还提供一种电池，包括正极极片、隔离膜以及如上所述的负极极片，隔离膜设置于正极极片与负极极片之间。
进一步的，纤维涂层与隔离膜之间的粘结力大于或等于5N/m。
本申请还提供一种电子装置，包括如上述所述的电池。
本申请中的负极极片中的纤维涂层为多孔结构，具有强度高、韧性好以及耐热性好的特点，有利于保护所述极片基体，并且能够有效地防止正负极短路的情况发生，例如防止穿刺、挤压等情形引起的正负极短路以及高温隔离膜失效后引起的正负极接触短路，进而降低短路概率，提高了电池的安全性。另外，由于纤维涂层的多孔结构及特定的含量组成，其并未阻隔锂离子和电解液的传输，保证了电池的正常使用。
附图说明
图1为本申请一实施方式的负极极片的结构示意图。
图2为本申请一实施方式的纤维涂层的扫描电镜(SEM)图。
图3为图2所示的纤维涂层在另一倍数下的SEM图。
图4为本申请一实施方式的电芯的结构示意图。
主要元件符号说明
负极极片                  100
极片基体                  10
纤维涂层                  30
负极集流体                11
负极活性层                15
正极极片                  200
隔离膜                    300
如下具体实施方式将结合上述附图进一步说明本申请。
具体实施方式
下面对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。除非另有定义，本文所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同。本文中在本申请的说明书中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本申请。
下面对本申请的一些实施方式作详细说明。在不冲突的情况下，下述的实施例及实施例中的特征可以相互组合。
请参阅图1至图3，本申请实施方式提供一种负极极片100，其包括极片基体10以及设置于极片基体10的表面的纤维涂层30。
极片基体10包括负极集流体11以及设置于负极集流体11的负极活性层15。
在本实施方式中，纤维涂层30设置于负极活性层15背离负极集流体11的表面。
纤维涂层30为多孔结构。在纤维涂层30中，基于纤维涂层30的总质量，以质量百分比计，包含90％至100％的纤维、0％至8％的粘结剂以及0％ 至2％的增稠剂。纤维涂层的多孔结构使得纤维涂层30的强度高、韧性好，进而有利于保护极片基体。
在本实施方式中，纤维涂层30的厚度为0.1μm至10μm。优选的，纤维涂层30的厚度为0.5μm至5μm。纤维涂层30的厚度越大，纤维涂层30的强度及耐热性越好，能够更有效地阻隔负极极片100与正极短路，进而安全性越高。然而，纤维涂层30的厚度越大，对锂离子的传导的影响也越大，进而越容易增加电池的阻抗；同时，纤维涂层30的厚度越大，也越容易降低电池的能量密度。
在本实施方式中，纤维涂层30的孔隙率为20％至70％。纤维涂层30设置于极片基体10表面时，电解液需穿过纤维涂层30再与极片基体10接触，并且锂离子在正负极间传输也需穿过纤维涂层30，因此，纤维涂层30的孔隙率越高，电解液浸润极片基体10的速度越快，锂离子的传输阻力也越小。然而，纤维涂层30的孔隙率过高时，纤维涂层30的强度将不足以避免铝箔的毛刺等结构穿过纤维涂层30的孔隙与极片基体10接触，使得纤维涂层30对极片基体10的保护作用减弱。
极片基体10被纤维涂层30覆盖的面积占极片基体10表面面积的50％及其以上(在本申请中，将上述占比称为纤维涂层的覆盖率)。若极片基体10被纤维涂层30覆盖的面积在极片基体10表面的占比过小，穿刺过程容易导致正负极的短路。
优选的，纤维涂层30与极片基体10之间的粘结力大于或等于5N/m，从而避免纤维涂层30从极片基体10上脱落。
纤维具有较高的熔点且不导电，其可选自但不仅限于羧甲基纤维素纤维、聚酯纤维以及聚砜类纤维中的至少一种。纤维的化学稳定性以及电化学稳定性良好。
每一纤维的长径比为20至5000。在本实施方式中，每一纤维的长度为10μm至50μm，以便于纤维之间搭接从而形成膜层，每一纤维的直径为 0.01μm至0.5μm。如图2及图3所示，为含有直径为30nm的羧甲基纤维素纤维的纤维涂层的SEM图。如果长径比过大时，形成纤维涂层的浆料在过滤时容易堵塞滤网，在涂布时则容易堵塞凹版辊的微孔；而长径比过小时，纤维的长度短，原料本身加工困难，也不利于形成完整的覆盖网络，即不利于纤维之间搭接形成膜层。
在本实施方式中，每一纤维的熔点大于或等于200℃，使得纤维涂层30具有较好的耐热性，有利于在高温的情况下保护极片基体。
粘结剂可选自但不仅限于丁苯橡胶、聚丙烯酸酯、聚丙烯酸、羧甲基纤维素钠、羧甲基纤维素锂、聚偏氟乙烯或聚乙二醇中的至少一种。
在本实施方式中，羧甲基纤维素钠、羧甲基纤维素锂、聚丙烯酸、聚乙醇也可作为增稠剂应用于纤维涂层中。
在本实施方式中，可将形成纤维涂层的浆料通过挤压、转印、印刷、喷涂等方式涂布于极片基体10的表面，而后干燥形成纤维涂层30。其中，形成纤维涂层的浆料的溶剂可选自但不仅限于水(如去离子水)、N-甲基吡咯烷酮、N,N-二甲基甲酰胺以及N,N-二甲基乙酰胺等。
将上述负极极片100应用于电池中。其中，请参阅图4，电池还包括正极极片200以及隔离膜300。隔离膜300设置于正极极片200与负极极片100之间。在电池中，负极极片100、隔离膜300以及正极极片200可构成堆叠式的电芯(即叠片型的电芯)，也可构成卷绕式的电芯。
在本实施方式中，纤维涂层30与隔离膜300之间的粘结力大于或等于5N/m，以避免外力作用下(例如撞击)负极极片100与隔离膜300错位导致电池的短路，进一步提高了电池的安全性。
上述电池可应用于电子装置中。电子装置可为但不仅限于手机、电脑、玩具等。
下面通过对比例及实施例对本申请进行具体说明。可以理解的，本申请中极片、隔离膜、电解液等的各尺寸、材质及/或比例不仅限于对比例及实施 例中记载的内容，具体可根据实际需要进行选择。
对比例1
正极极片的制备：采用铝箔作为正极集流体，在铝箔的表面均匀涂布正极活性浆料而后进行冷压形成正极活性层，从而制得正极极片。其中，正极活性浆料由97.8wt％的LiCoO 2(LCO，正极活性材料)、0.8wt％的聚偏二氟乙烯(PVDF)和1.4wt％的导电炭黑组成。
负极极片的制备：采用铜箔作为负极集流体，在铜箔的表面均匀涂布负极活性浆料而后进行冷压形成负极活性层，从而制得负极极片。其中，负极活性浆料由97.7wt％的人造石墨、1.3wt％的羧甲基纤维素(CMC)以及1.0wt％的丁苯橡胶(SBR)组成。负极活性层的厚度为200μm。
电池的制备：将上述正极极片及上述负极极片进行卷绕，其中，正极极片和负极极片之间以聚乙烯(PE)膜作为隔离膜进行分隔，进而制得卷绕式电芯；将卷绕式电芯经顶侧封、喷码、真空干燥、注入电解液、高温静置后进行化成及容量测试，从而制得电池。
对比例2
对比例2与对比例1的区别在于负极极片的制备。
负极极片的制备为：采用铜箔作为负极集流体，在铜箔的表面均匀涂布负极活性浆料而后进行冷压形成负极活性层，从而制得极片基体；其中，负极活性浆料由97.7wt％的人造石墨、1.3wt％的羧甲基纤维素(CMC)以及1.0wt％的丁苯橡胶(SBR)组成，负极活性层的厚度为200μm。在极片基体的表面涂布纤维浆料并干燥形成纤维涂层，进而制得负极极片。纤维浆料由纤维、粘结剂以及增稠剂溶于去离子水中后以恒定转速分散制得。其中，纤维浆料的固含量为10％。在纤维涂层中，纤维、粘结剂以及增稠剂按质量百分比计为85％的羧甲基纤维素纤维、10％的丁苯橡胶乳液及5％的羧甲基纤维素。纤维的长径比为500。纤维涂层的厚度为0.5μm，孔隙率为70％，覆盖率为90％。
对比例3
对比例3与对比例2的区别在于纤维、粘结剂以及增稠剂按质量百分比计为97％的羧甲基纤维素纤维、2％的丁苯橡胶乳液及1％的羧甲基纤维素；纤维涂层的覆盖率为45％。
实施例1
实施例1与对比例1的区别在于负极极片的制备。
负极极片的制备为：采用铜箔作为负极集流体，在铜箔的表面均匀涂布负极活性浆料而后进行冷压形成负极活性层，从而制得极片基体；其中，负极活性浆料由97.7wt％的人造石墨、1.3wt％的羧甲基纤维素钠(CMC)以及1.0wt％的丁苯橡胶(SBR)组成，负极活性层的厚度为200μm。在极片基体的表面涂布纤维浆料并干燥形成纤维涂层，进而制得负极极片。纤维浆料由纤维、粘结剂以及增稠剂溶于去离子水中后以恒定转速分散制得。其中，纤维浆料的固含量为10％。在纤维涂层中，纤维、粘结剂以及增稠剂按质量百分比计为97％的羧甲基纤维素纤维、2％的丁苯橡胶乳液及1％的羧甲基纤维素。纤维的长径比为500。纤维涂层的厚度为0.5μm，孔隙率为70％，覆盖率为90％。
实施例2
实施例2与实施例1的区别在于纤维涂层的厚度为5μm。
实施例3
实施例3与实施例1的区别在于纤维涂层的厚度为3μm。
实施例4
实施例4与实施例3的区别在于纤维的长径比为300。
实施例5
实施例5与实施例3的区别在于纤维为聚砜类纤维。
实施例6
实施例6与实施例3的区别在于在纤维涂层中，按质量百分比计，包含 为90％的羧甲基纤维素纤维、9％的丁苯橡胶乳液及1％的羧甲基纤维素。
实施例7
实施例7与实施例2的区别在于在纤维涂层中，按质量百分比计，包含为100％的羧甲基纤维素纤维。
实施例8
实施例8与实施例3的区别在于在纤维涂层中，按质量百分比计，包含为97％的聚酯类纤维、2％的聚丙烯酸酯乳液及1％的羧甲基纤维素锂。
实施例9
实施例9与实施例3的区别在于纤维的长径比为20。
实施例10
实施例10与实施例3的区别在于纤维的长径比为5000。
实施例11
实施例11与实施例3的区别在于纤维的长径比为250。
实施例12
实施例12与实施例4的区别在于在纤维涂层中，按质量百分比计，包含为97％的聚酯类纤维、2％的丁苯橡胶乳液及1％的聚丙烯酸；纤维长径比为300。
实施例13
实施例13与实施例3的区别在于纤维涂层的孔隙率为20％。
实施例14
实施例14与实施例3的区别在于在纤维涂层中，按质量百分比计，包含为97％的羧甲基纤维素纤维、2％的聚丙烯酸酯乳液及1％的聚丙烯酸。
实施例15
实施例15与实施例3的区别在于纤维涂层的孔隙率为45％。
实施例16
实施例16与实施例3的区别在于纤维涂层的孔隙率为60％。
实施例17
实施例17与实施例3的区别在于在纤维涂层中，按质量百分比计，包含为98.5％的羧甲基纤维素纤维、0.5％的丁苯橡胶乳液及1％的羧甲基纤维素。
实施例18
实施例18与实施例3的区别在于在纤维涂层中，按质量百分比计，包含为95％的羧甲基纤维素纤维、4％的丁苯橡胶乳液及1％的羧甲基纤维素。
实施例19
实施例19与实施例3的区别在于纤维涂层的覆盖率为50％。
实施例20
实施例20与实施例3的区别在于纤维涂层的覆盖率为100％。
实施例21
实施例21与实施例3的区别在于在纤维涂层中，按质量百分比计，包含为97％的羧甲基纤维素纤维、2％的聚偏氟乙烯粉末及1％的聚乙烯醇。
实施例22
实施例22与实施例1的区别在于纤维涂层的厚度为0.1μm，纤维的长径比为350。
实施例23
实施例23与实施例1的区别在于纤维涂层的厚度为10μm。
测定对比例1、对比例3及实施例1-23的各个电池的容量、厚度、宽度、长度以确定各个电池的体积能量密度。测定上述各个电池的穿钉性能以确定各个电池的机械安全性能。测定对比例1-3及实施例1-23各个电池的放电倍率性能以确定各个电池的动力学性能。
上述电池容量的测定方法为：在25±3℃环境中静置30min，以0.5C(1C为电池的额定容量)电流恒流充电至电池电压至4.4V(额定电压)，而后转恒压充电，电流至0.05C时停止充电；电池静置30min；而后以0.2C电流将 电池放电至3.0V，静置30min；取放电容量作为电池的实际容量。
以上述电池的实际容量，乘以电芯实际的电压，并除以电池的体积，即得到电池的体积能量密度，并记载于下表1中。
上述电池的穿钉性能的测定方法为：每个对比例或实施例中分别取电池10枚，在25±3℃环境下满充，具体为以0.5C电流恒流充电至4.4V，恒压充电至0.05C电流截止。在常温条件下对每个电池进行穿钉，穿钉速度设置为30mm/s，穿钉深度以钢钉锥度穿过电池为准。若穿钉后该电池不起火、不爆炸，则该电池通过穿钉测试，反之，则不通过。如此，统计10枚电池中通过穿钉测试的电池数量。其中，穿钉时采用直径为4mm的钢钉，材质为碳钢，锥度为16.5mm，钢钉总长为100mm。检测每个对比例或实施例中电池的穿钉通过情况并记载于下表1中。
上述电池的放电倍率性能的测定方法为：将电池在25℃±3℃环境静置30min后，以0.5C恒定电流充电至4.4V，而后恒压充电至0.05C电流截止；电池搁置30min；而后以0.2C恒定电流放电至3.0V，获取放电容量C1；电池搁置30min；而后以0.5C恒定电流充电至4.4V，再恒压充电至0.05C电流截止；电池搁置30min；而后以2.0C恒定电流放电至3.0V，获取放电容量C2，C2/C1即是该电池在2C下的放电倍率。具体数据记载于下表1及表2中。
测定实施例1-23中负极极片中的纤维涂层与相应的极片基体之间的粘结力，具体方法为：将负极极片通过双面胶粘贴在平滑的钢板上，负极极片背离钢板的表面粘贴一胶纸，并将胶纸的一端固定在拉力机上，通过拉力机拉动胶纸，读取胶纸拉伸时的粘结力，并用读取的粘结力除以胶纸的宽度，即可得到纤维涂层与极片基体之间的粘结力。具体数据记载于下表1中。
测定实施例1-23中负极极片中的纤维涂层与相应的隔离膜之间的粘结力，具体方法为：将负极极片与隔离膜层叠在一起并在85℃、-1MPa的条件下热压2min，其中，隔离膜与纤维涂层粘接，隔离膜的长度大于负极极片 的长度以使隔离膜从负极极片一端伸出，隔离膜从负极极片伸出的部分固定在拉力机上，通过拉力机拉动隔离膜，读取隔离膜拉伸时的粘结力，并用读取的粘结力除以隔离膜的宽度，即可得到纤维涂层与隔离膜之间的粘结力。具体数据记载于下表1中。
对对比例1、对比例3及实施例1-23分别进行挤压测试及热箱测试。挤压测试的测定方法及热箱测试的测定方法的具体操作如下。
挤压测试的测定方法：以一定电流满充至电芯满充电压,然后在满充电压下恒压充电到一定电流(如：以0.5C恒流满充到4.45V，然后在4.45V恒压下充电到电流达到0.025C)；测试前拍摄照片，而后用8mm方型压棒，以13.0kN的压力挤压电芯头部进行测试，并在测试后拍摄照片。如电池未爆炸未起火，则电池通过挤压测试，反之，则未通过。如此，统计10枚电池中通过挤压测试的电池数量，并记载于下表1中。
热箱测试的测定方法：以一定电流满充至电芯满充电压,然后在满充电压下恒压充电到一定电流(如：以0.5C恒流满充到4.45V，然后在4.45V恒压下充电到电流达到0.025C)；在25±5℃下静置60min，测试前检查外观并拍照，再以5℃/min±2℃/min的速率分别升至120℃±2℃、130℃±2℃、135℃±2℃、140℃±2℃，而后保持30min进行测试，并再测试后检查外观并拍照。如电池未爆炸未起火，则电池通过热箱测试，反之，则未通过。如此，统计10枚电池中通过热箱测试的电池数量，并记载于下表1中。
表1
Figure PCTCN2021075641-appb-000001
Figure PCTCN2021075641-appb-000002
表2
Figure PCTCN2021075641-appb-000003
Figure PCTCN2021075641-appb-000004
本申请中的负极极片中的纤维涂层为多孔结构，具有强度高、韧性好以及耐热性好的特点，有利于保护极片基体，并且能够有效地防止正负极短路的情况发生，例如防止穿刺、挤压等情形引起的正负极短路以及高温隔离膜失效后引起的正负极接触短路，进而降低短路概率，提高了电池的安全性。另外，由于纤维涂层的多孔结构及特定的含量组成，其并未阻隔锂离子和电解液的传输，保证了电池的正常使用。
另外，对于本领域的普通技术人员来说，可以根据本申请的技术构思做出其它各种相应的改变与变形，而所有这些改变与变形都应属于本申请的保护范围。

Claims (12)

  1. 一种负极极片，包括：
    极片基体，所述极片基体包括负极集流体以及设置于所述负极集流体的表面的负极活性层；
    其特征在于，所述负极极片还包括：
    纤维涂层，设置于所述极片基体的表面，所述纤维涂层为多孔结构；
    其中，基于纤维涂层的总质量以质量百分比计，所述纤维涂层中包括90％至100％的纤维、0％至8％的粘结剂以及0％至2％的增稠剂。
  2. 如权利要求1所述的负极极片，其特征在于，所述纤维选自羧甲基纤维素、聚酯纤维以及聚砜类纤维中的至少一种，所述粘结剂选自丁苯橡胶、聚丙烯酸酯、聚丙烯酸、羧甲基纤维素钠、羧甲基纤维素锂、聚偏氟乙烯以及聚乙二醇中的至少一种。
  3. 如权利要求1所述的负极极片，其特征在于，每一纤维的长径比为20至5000，其中，每一纤维的长度为10μm至50μm，每一纤维的直径为0.01μm至0.5μm。
  4. 如权利要求1所述的负极极片，其特征在于，每一纤维的熔点大于或者等于200℃。
  5. 如权利要求1所述的负极极片，其特征在于，所述纤维涂层的厚度为0.1μm至10μm。
  6. 如权利要求1所述的负极极片，其特征在于，所述纤维涂层的厚度为0.5μm至5μm。
  7. 如权利要求1所述的负极极片，其特征在于，所述纤维涂层的孔隙率为20％至70％。
  8. 如权利要求1所述的负极极片，其特征在于，所述纤维涂层与所述极片基体之间的粘结力大于或等于5N/m。
  9. 如权利要求1所述的负极极片，其特征在于，所述极片基体被所述纤维涂层覆盖的面积占所述极片基体表面的50％及其以上。
  10. 一种电池，包括正极极片以及隔离膜，其特征在于，所述电池还包括如权利要求1至9任意一项所述的负极极片，所述隔离膜设置于所述正极极片与所述负极极片之间。
  11. 如权利要求10所述的电池，其特征在于，所述纤维涂层与所述隔离膜之间的粘结力大于或等于5N/m。
  12. 一种电子装置，其特征在于，包括如权利要求10或11所述的电池。
PCT/CN2021/075641 2020-02-06 2021-02-05 负极极片、应用所述负极极片的电池以及电子装置 WO2021155852A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010081304.0A CN113224297A (zh) 2020-02-06 2020-02-06 负极极片、应用所述负极极片的电池以及电子装置
CN202010081304.0 2020-02-06

Publications (1)

Publication Number Publication Date
WO2021155852A1 true WO2021155852A1 (zh) 2021-08-12

Family

ID=77085489

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/075641 WO2021155852A1 (zh) 2020-02-06 2021-02-05 负极极片、应用所述负极极片的电池以及电子装置

Country Status (2)

Country Link
CN (1) CN113224297A (zh)
WO (1) WO2021155852A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114478958A (zh) * 2022-01-07 2022-05-13 瑞红锂电池材料(苏州)有限公司 改性sbr粘结剂及其制备方法和应用
CN117154237A (zh) * 2023-08-31 2023-12-01 惠州市柯比电子有限公司 一种锂离子电池制造设备及锂离子电池制造方法
CN117374438A (zh) * 2023-12-08 2024-01-09 中国第一汽车股份有限公司 负极极片及其制备方法、包含其的锂离子电池

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012059486A (ja) * 2010-09-08 2012-03-22 Konica Minolta Holdings Inc リチウムイオン二次電池及びリチウムイオン二次電池用多孔質絶縁層
CN104466231A (zh) * 2013-09-24 2015-03-25 北京有色金属研究总院 一种锂离子二次电池及其制备方法
CN107516721A (zh) * 2016-06-16 2017-12-26 宁德新能源科技有限公司 电芯及储能装置
CN107534129A (zh) * 2015-04-06 2018-01-02 株式会社东芝 电极、电极组及非水电解质电池
CN109802083A (zh) * 2019-03-29 2019-05-24 宁德新能源科技有限公司 电化学装置

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100738054B1 (ko) * 2004-12-18 2007-07-12 삼성에스디아이 주식회사 음극 활물질, 그 제조 방법 및 이를 채용한 음극과 리튬전지
CN104508860B (zh) * 2012-07-24 2016-06-29 株式会社东芝 二次电池
CN104124414B (zh) * 2013-04-28 2017-06-20 华为技术有限公司 一种锂离子电池复合电极片及其制备方法和锂离子电池
JP6219113B2 (ja) * 2013-09-30 2017-10-25 株式会社東芝 二次電池
CN109923699B (zh) * 2016-11-07 2022-03-15 日产自动车株式会社 锂离子电池用负极和锂离子电池

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012059486A (ja) * 2010-09-08 2012-03-22 Konica Minolta Holdings Inc リチウムイオン二次電池及びリチウムイオン二次電池用多孔質絶縁層
CN104466231A (zh) * 2013-09-24 2015-03-25 北京有色金属研究总院 一种锂离子二次电池及其制备方法
CN107534129A (zh) * 2015-04-06 2018-01-02 株式会社东芝 电极、电极组及非水电解质电池
CN107516721A (zh) * 2016-06-16 2017-12-26 宁德新能源科技有限公司 电芯及储能装置
CN109802083A (zh) * 2019-03-29 2019-05-24 宁德新能源科技有限公司 电化学装置

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114478958A (zh) * 2022-01-07 2022-05-13 瑞红锂电池材料(苏州)有限公司 改性sbr粘结剂及其制备方法和应用
CN114478958B (zh) * 2022-01-07 2023-08-29 瑞红锂电池材料(苏州)有限公司 改性sbr粘结剂及其制备方法和应用
CN117154237A (zh) * 2023-08-31 2023-12-01 惠州市柯比电子有限公司 一种锂离子电池制造设备及锂离子电池制造方法
CN117374438A (zh) * 2023-12-08 2024-01-09 中国第一汽车股份有限公司 负极极片及其制备方法、包含其的锂离子电池

Also Published As

Publication number Publication date
CN113224297A (zh) 2021-08-06

Similar Documents

Publication Publication Date Title
WO2021155852A1 (zh) 负极极片、应用所述负极极片的电池以及电子装置
CN105826508B (zh) 压电陶瓷复合隔膜、其制备方法及锂离子电池
WO2020181681A1 (zh) 一种混合固液电解质锂蓄电池
CN111653717B (zh) 一种复合隔膜的制备方法、复合隔膜和锂离子电池
WO2016165633A1 (en) Polymer composite membrane and preparation method thereof, gel electrolyte and lithium ion battery having the same
US20130236765A1 (en) Polymer li-ion battery and the separator thereof
CN111785925B (zh) 极片及应用、含有该极片的低温升高安全性锂离子电池
US9882189B2 (en) Separator for nonaqueous electrolyte battery, and nonaqueous electrolyte battery
US20180233727A1 (en) Separator for a non-aqueous secondary battery and non-aqueous secondary battery
TW202105805A (zh) 電極製造方法、電極及二次電池
CN112467308B (zh) 一种隔膜及其制备方法、锂离子电池
WO2022100661A1 (zh) 一种负极片及其应用
CN106229474B (zh) 一种用于锂离子电池集流体的涂层浆料以及一种锂离子电池
WO2023155604A1 (zh) 复合隔膜及电化学装置
CN111725511B (zh) 一种锂离子二次电池极片及锂离子二次电池
JP4439226B2 (ja) 非水電解質二次電池
JP4140517B2 (ja) リチウムイオン二次電池およびその構成法
CN114006024A (zh) 一种隔膜及含有该隔膜的电池
WO2021243611A1 (zh) 绝缘胶带、极片和电化学装置
CN101826640B (zh) 一种锂离子电池用极芯和使用该极芯的锂离子电池
JP7054997B2 (ja) 非水系二次電池用セパレータ、非水系二次電池、非水系二次電池用セパレータの製造方法、および、非水系二次電池用コーティング組成物
WO2022156459A1 (zh) 锂离子电池的负极片、锂离子电池和电子设备
JP2014026946A (ja) 非水電解質電池用セパレータ及び非水電解質電池
JP7054996B2 (ja) 非水系二次電池用セパレータ、非水系二次電池および非水系二次電池用セパレータの製造方法
WO2023246704A1 (zh) 一种锂离子电池极片及其制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21751082

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21751082

Country of ref document: EP

Kind code of ref document: A1