1279 results about "Positive current" patented technology

A lithium battery includes: a housing in which an accommodation space is formed; a core disposed in the accommodation space; a negative cover disposed at a first end of the housing; a positive cover disposed at a second end of the housing; a positive current collecting disk disposed on a side of the positive cover close to the core; and a support member disposed between the positive cover and the positive current collecting disk and abutting against the positive current collecting disk.

The invention provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a positive pole piece, an isolating membrane, a negative pole piece and electrolyte, and the positive pole piece, the isolating membrane and the negative pole piece are arranged in a laminated manner; the positive pole piece comprises a positive current collector and a positive active layer arranged on at least one side of the positive current collector, the negative pole piece comprises a negative current collector and a negative active layer arranged on at least one side of the negative current collector, and the positive active layer comprises lithium iron phosphate primary particles; the isolating membrane comprises a base membrane and a bonding layer, the bonding layer is of a porous continuous structure, and the bonding layer is at least arranged on one side, facing the positive electrode active layer, of the base membrane; the electrolyte comprises a first solvent, and the first solvent comprises one or more of dimethyl carbonate and linear carboxylic ester. The battery monomer has relatively good cycle performance.

The invention provides a secondary battery and an electric device. Particularly, the lithium ion secondary battery comprises a positive electrode plate, the positive electrode plate comprises a positive electrode current collector and a positive electrode film layer arranged on the positive electrode current collector and comprising a positive electrode active material, the positive electrode active material comprises a lithium-containing transition metal oxide and a lithium-containing transition metal phosphate, and the lithium-containing transition metal oxide and the lithium-containing transition metal phosphate are arranged on the positive electrode current collector. The lithium-containing transition metal oxide comprises a nickel element, a cobalt element, a manganese element and / or an aluminum element, and a silicon element; the average mass concentration ratio of silicon elements in an external area corresponding to the position where the surfaces of the primary particles of the lithium-containing transition metal oxide extend to the center by 1 / 4 radius is larger than the average mass concentration ratio of silicon elements in a core area corresponding to the position where the centers of the primary particles extend to the surfaces by 1 / 4 radius, and the lithium-containing transition metal phosphate comprises iron elements. The lithium-containing transition metal phosphate comprises secondary particles formed by agglomeration of primary particles.

The invention relates to a battery monomer, a battery device and a power utilization device, the battery monomer comprises an electrode assembly and an electrolyte, the electrode assembly comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive current collector and a positive film layer, the positive film layer comprises a positive active material, the positive active material comprises lithium-containing phosphate of an olivine structure, and the electrolyte is a lithium-containing lithium-containing phosphate of a lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing lithium-containing electrolyte. The resistance of the positive pole piece is 0.1 ohm to 30 ohm, the negative pole piece comprises a negative current collector and a negative film layer, the resistance of the negative pole piece is 0.001 ohm to 0.01 ohm, the electrolyte comprises an organic solvent, the organic solvent comprises a chain ester solvent, and the mass content of the chain ester solvent in the organic solvent is 5% to 75%; the conductivity of the electrolyte at room temperature is 13 mS / cm to 20 mS / cm. The heat production amount of the battery monomer can be reduced, and the use reliability and the cycle performance of the battery monomer can be improved.

The invention provides a battery monomer, a battery device and a power utilization device. Each battery monomer comprises a shell and an electrode assembly in the shell, the electrode assembly comprises a positive pole piece, a negative pole piece and an isolating membrane between the two pole pieces, the positive pole piece comprises a positive current collector and a positive active layer arranged on at least one side of the positive current collector, and the positive active layer comprises a positive active material; the positive electrode active material comprises a nickel-containing lithium transition metal oxide and a lithium-containing phosphate, the molar weight of the Ni element in the nickel-containing lithium transition metal oxide accounts for 70-95% of the total molar weight of the transition metal, the positive electrode active material comprises Ni, Co, Mn, Fe and Li elements, and the ratio of the mass of the Ni element in the positive electrode active material to the sum of the mass of the Fe element and the mass of the Mn element is 0.15-2.

The invention provides a COT step-down converter comprising an inductive current detection circuit configured to detect an inductive current flowing through an inductor connected to a system output of an output voltage of an output system of the COT step-down converter, and generate a current zero-crossing detection signal indicating whether the inductive current crosses zero, the inductive current zero-crossing means that the inductive current is changed from positive current to negative current; and a sleep mode control circuit configured to generate a sleep mode control signal for controlling one or more circuit modules in the COT buck converter to change from an operating state to a closed state based on the current zero-crossing detection signal, an output feedback voltage representing a system output voltage of the COT buck converter, and a predetermined reference voltage.

The invention belongs to the technical field of batteries, and particularly discloses a battery monomer, a battery device and a power utilization device. The battery monomer comprises a positive pole piece, wherein the positive pole piece comprises a positive current collector and a positive film layer; the positive electrode film layer is provided with a first surface far away from the positive electrode current collector and a second surface opposite to the first surface; the distance between the first surface and the second surface is H; in the stacking direction, a region formed by extending from the second surface of the positive electrode film layer to a 0.1 * H position is marked as a first region of the positive electrode film layer; in the stacking direction, a region formed by extending from the first surface of the positive electrode film layer to a 0.1 * H position is marked as a second region of the positive electrode film layer; the types of the positive active materials in the first region and the second region can be the same or different, the positive active materials in each region are matched with the carbon nanotubes, and the direct current resistance of the battery is reduced by improving the conductivity of the pole piece.

A positive electrode sheet, a secondary battery (4), and an electric device (5). The positive pole piece comprises a positive current collector; the bottom coating is positioned on at least one side of the positive current collector and comprises a conductive agent and a binder; the positive electrode active material layer is positioned on one side, far away from the positive electrode current collector, of the bottom coating layer and comprises a positive electrode active material; the thickness of the bottom coating layer is marked as L, and the thickness of the bottom coating layer meets the formula (I); wherein Dv50 is the corresponding particle size when the cumulative particle size distribution number of particles in the volume distribution of the positive electrode active material reaches 50%, and the unit is [mu] m; pD represents the compaction density of the positive pole piece, and the unit is g / cm < 3 >. # imgabs0 #

The invention relates to the technical field of batteries, in particular to a battery. Comprising a positive plate and electrolyte, the positive plate comprises a positive current collector and a coating positioned on the surface edge of at least one side of the positive current collector along the length direction; the coating comprises filling particles, and the filling particles comprise at least one of inorganic particles and nitrogen-containing particles; the electrolyte comprises non-fluorinated cyclic carbonate and fluorinated ethyl acetate; the non-fluorinated cyclic carbonate comprises propylene carbonate and optional ethylene carbonate; on the basis of the total mass of the electrolyte, the content ratio C1 of the non-fluorinated cyclic carbonate is smaller than or equal to 25%, the content ratio C11 of the propylene carbonate is 3.1%-24.9%, the content ratio C12 of the ethylene carbonate is 0%-5%, and the content ratio C2 of the fluorinated ethyl acetate is 20.2%-70%. The battery provided by the invention can improve the problem of lithium precipitation under low-temperature discharge, and has relatively good short-circuit safety performance and relatively low high-temperature gas production rate.

The invention relates to a battery monomer, a battery device and a power utilization device, the battery monomer comprises an electrode assembly, the electrode assembly comprises a plurality of positive pole pieces and a plurality of negative pole pieces, and the positive pole pieces and the negative pole pieces are stacked in the thickness direction of the battery monomer; the positive pole piece comprises a positive pole current collecting part and a positive pole film layer arranged on at least one side of the positive pole current collecting part, the ratio of the size of the positive pole film layer in the length direction of the battery monomer to the size of the positive pole film layer in the width direction of the battery monomer is 4-7, and the size of the positive pole film layer in the length direction is 300-650 mm; the positive electrode film layer includes a lithium-containing phosphate of an olivine structure and a lithium-containing iron oxide. The battery monomer provided by the invention can improve the power performance and the high-temperature cycle performance at the same time.

The invention provides a battery cell and a battery, and the battery cell comprises a positive plate which comprises a positive current collector and positive active material layers respectively arranged on two opposite sides of the positive current collector; the negative plate is located on at least one side of the positive plate, the polarity of the positive plate is opposite to that of the negative plate, and the negative plate comprises a negative current collector and negative active material layers arranged on the two opposite sides of the negative current collector; the diaphragms are positioned between the adjacent positive plates and negative plates; the positive plate comprises a plurality of first bumps formed on the positive active material layer and a plurality of first grooves arranged opposite to the first bumps, and the negative plate comprises a plurality of second bumps formed on the negative active material layer and a plurality of second grooves arranged opposite to the second bumps; the first protruding block and the second groove are oppositely arranged, and the second protruding block and the first groove are oppositely arranged. According to the invention, the electrolyte distribution is improved, the electrolyte infiltration effect is improved, and the cycle life of the battery cell is further prolonged.

The invention provides a lithium ion secondary battery, a battery device, a power utilization device, a preparation method of a positive electrode active material and a preparation method of a positive electrode plate. The lithium ion secondary battery comprises a positive pole piece, a negative pole piece and an electrolyte, the positive pole piece comprises a positive current collector and a positive film layer arranged on at least one side of the positive current collector, the positive film layer comprises a positive active material, and the positive active material comprises lithium-containing transition metal phosphate particles of which at least partial surfaces are provided with carbon coating materials; in the tangent plane of the positive electrode film layer along the thickness direction of the pole piece, the area proportion of particles with the particle size greater than or equal to 1 mu m is 30.0-50.0%; and the mass ratio of the magnetic substance in the positive electrode film layer is greater than or equal to 20 ppm and less than or equal to 1980 ppm.

The invention provides an electrochemical device and an electronic device, the electrochemical device comprises a positive pole piece, the positive pole piece comprises a positive current collector, a first coating and a positive material layer, the first coating is arranged on the surface of the positive current collector, and the positive material layer is arranged on the surface, away from the positive current collector, of the first coating; the first coating comprises inorganic particles, and the inorganic particles comprise at least one of nano boehmite, aluminum oxide, titanium dioxide, magnesium oxide, zirconium oxide or zinc oxide; the positive electrode material layer comprises a first conductive agent, and the first conductive agent comprises a first carbon nanotube; the length of the first carbon nanotube is 2-5 [mu] m, and the diameter of the first carbon nanotube is 2-100 nm; and the ion transference number of the positive electrode material layer is 0.4-0.47. The electrochemical device provided by the invention can consider the nail penetrating safety performance, the low-temperature cycle performance and the quick charging performance.

The invention provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises an electrode assembly, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane positioned between the positive plate and the negative plate; the negative plate comprises a negative current collector and a negative active layer located on at least one side of the negative current collector, the negative active layer comprises a negative material, the negative material comprises a negative active material, and the negative active material comprises graphite; the positive plate comprises a positive current collector and a positive active layer positioned on at least one side of the positive current collector, the positive active layer comprises a positive material, the positive material comprises a positive active material, and the positive active material comprises lithium iron phosphate and a lithium manganese iron phosphate material; the surface density of the positive electrode active layer is 200 to 370 mg / 1540.25 mm < 2 >; and when the battery monomer is in a 100% SOC state, the compaction density of the positive electrode active layer is 2.27-2.67 g / cm < 3 >. The battery monomer has the advantages of low cost, high energy density and long cycle life.

The invention discloses a permanent magnet synchronous motor current dynamic coupling correction method, which comprises the following steps of collecting motor three-phase stator current, performing Clark transformation to obtain a current value under an alpha-beta static coordinate system, and meanwhile, collecting through a position sensor to obtain an electrical angle true value; performing low-pass filtering calculation on the current value under the alpha-beta static coordinate system to obtain a filtering current value, and performing operation through a sliding-mode observer and a PLL phase-locked loop to obtain an electrical angle observation value; calculating to obtain a compensation adjustment coefficient according to the true value and the observed value of the electrical angle, and further calculating to obtain a current value after phase offset compensation; and performing complementary filtering calculation on the filtering current value and the current value after phase offset compensation to obtain a coupling correction current value for current loop calculation, inputting the coupling correction current value into a motor control current loop PID algorithm, and generating a PWM driving signal to drive a motor in combination with vector control. According to the method, the problems of high-frequency interference and phase deviation of current sampling can be solved, so that the motor control efficiency and the dynamic performance are improved.

The invention provides a lithium secondary battery and an electric device. The lithium secondary battery comprises a positive pole piece, a negative pole piece and an electrolyte, the positive pole piece comprises a positive current collector and a positive film layer arranged on at least one side of the positive current collector, the positive film layer comprises a positive active material, and the positive active material comprises lithium-containing transition metal phosphate particles; the lithium-containing transition metal phosphate particles comprise lithium iron phosphate particles, the lithium iron phosphate particles comprise a doping element Q, and the doping element Q comprises one or more of W, Al, Na, K, Mg, Cu, Mn, Cr, Zn, Pb, Ca, Co, Ni, Sr, Nb, V, Ti, B, S, Si, N, F, Cl, Br and Zr; the electrolyte comprises propylene carbonate and a compound with a formula I, R is selected from halogen, and n is an integer selected from 1-6. The lithium secondary battery provided by the invention has relatively good low-temperature fast-charging performance and also has excellent cycling stability.

The invention relates to the technical field of batteries, and discloses a battery cell and a battery, the battery cell comprises a negative pole piece, a diaphragm and a positive pole piece; the negative pole piece comprises a negative current collector and a negative active material coating; the positive pole piece comprises a positive current collector and a positive active material coating; the diaphragm comprises a base material, a first coating and a second coating, wherein the porosity of the first coating is A, the thickness of the first coating is a [mu] m, the porosity of the second coating is B, the thickness of the second coating is b [mu] m, the porosity of the negative electrode active material coating is C, the thickness of the negative electrode active material coating is c [mu] m, the porosity of the positive electrode active material coating is D, and the thickness of the positive electrode active material coating is d [mu] m; and by limiting that [(Dd + Bb) / (b + d)] / [(Aa + Cc) / (a + c)] is larger than or equal to 0.8 and smaller than or equal to 1.2, the porosity of the two sides of the base material of the diaphragm reaches a relatively close state, the cycle performance of a battery cell is improved, and the stability and reliability of the battery in the long-term use process are guaranteed.

The invention provides a secondary battery and an electric device, and relates to the field of batteries. The secondary battery comprises a positive pole piece, a negative pole piece and an isolating membrane, the positive pole piece comprises a positive current collector and a positive membrane layer arranged on at least one side surface of the positive current collector, and the compaction density of the positive membrane layer is 2.0-3.0 g / cm < 3 >; the negative pole piece comprises a negative current collector and a negative film layer located on at least one surface of the negative current collector, and the compaction density of the negative film layer is 1.4 g / cm < 3 >-1.85 g / cm < 3 >; the isolating membrane comprises a base membrane, the thickness of the base membrane ranges from 4 micrometers to 12 micrometers, the base membrane is provided with nanopores, and the average pore size of the nanopores ranges from 10 nm to 300 nm. The secondary battery has high energy density and improved safety performance.

The invention provides a positive pole piece, a preparation method thereof and a lithium ion battery. The positive pole piece comprises a positive current collector and a negative current collector, the first active coating is arranged on the surface of at least one side of the positive electrode current collector; the raw materials of the first active coating comprise a first main material, a first conductive agent and a low-swelling binder; the second active coating is arranged on the surface of one side, relatively far away from the positive electrode current collector, of the first active coating; and raw materials of the second active coating comprise a second main material, a second conductive agent and a high-swelling binder. Different types of binders are introduced into the first active coating and the second active coating, so that the tortuosity and porosity of the pole piece are changed, the diffusion rate of lithium ions is effectively improved, the concentration polarization of the surface layer of the pole piece is reduced, and the rate and cycle performance of the battery are remarkably improved. Particularly, the positive pole piece can achieve the goal of improving the multiplying power and the cycle performance without increasing the proportion of the conductive agent.

The invention relates to the field of electric power, and discloses an electric energy metering method, system and device and a storage medium, and the method comprises the steps: employing an FIR zero compensation angle difference algorithm to correct a synchronization error angle difference between a current signal and a voltage signal, employing a self-convolution cascade zero-pole low-pass filter algorithm to carry out the filtering processing of a synchronization current signal and a synchronization voltage signal, and obtaining a current signal and a voltage signal; correcting a real-time phase difference between the filtering current signal and the filtering voltage signal by adopting a high-real-time FIR zero-step angular difference algorithm to obtain a corrected current signal and a corrected voltage signal, sampling to obtain current data and voltage data, and obtaining an initial electric energy metering result according to the current data and the voltage data; and obtaining environmental factors, calling a pre-trained electric energy metering error prediction model to obtain an electric energy metering prediction error, and obtaining a final electric energy metering result according to the initial electric energy metering result and the electric energy metering prediction error. The electric energy metering method with high accuracy and high linearity is provided, and the problem that an existing electric energy metering mode is large in measurement error is solved.

The invention provides an electrode assembly, a battery monomer, a battery and electric equipment. The electrode assembly comprises a positive pole piece and a negative pole piece which are arranged in a stacked mode. The positive pole piece comprises a positive current collector and a positive active material layer, the positive current collector comprises a positive coating area and a positive pole lug, the positive active material layer is at least partially coated on the positive coating area, the positive pole lug is connected to the end part of the positive coating area along a first direction, and the first direction is perpendicular to the overlapping direction of the positive pole piece and the negative pole piece. The positive pole piece comprises a positive active material layer, the negative pole piece comprises a negative active material layer, the positive active material layer and the negative active material layer are oppositely arranged, and in the first direction, the two ends of the negative active material layer both exceed the positive active material layer. The positive electrode active material layer comprises a positive electrode main body part and a positive electrode edge part, the positive electrode edge part is arranged on one side, deviating from the positive electrode tab in the first direction, of the positive electrode main body part, and the positive electrode edge part is configured as follows: the unit area capacity of the positive electrode edge part is smaller than that of the positive electrode main body part.

The invention provides a lithium ion secondary battery and an electric device. Particularly, the invention provides a lithium ion secondary battery, which is characterized in that the lithium ion secondary battery comprises a positive pole piece, the positive pole piece comprises a positive current collector and a positive film layer which is arranged on the positive current collector and comprises a positive active material, the positive electrode active material comprises a lithium-containing transition metal oxide and a lithium-containing transition metal phosphate, and the lithium-containing transition metal oxide comprises a nickel element, a cobalt element, a manganese element and / or an aluminum element and a zirconium element; the content of a zirconium element in a core area corresponding to the part, extending to 1 / 2 radius from the center of a primary particle of the lithium-containing transition metal oxide to the surface, of the lithium-containing transition metal oxide accounts for 40%-60%, the lithium-containing transition metal phosphate comprises an iron element, and the lithium-containing transition metal phosphate comprises a secondary particle formed by agglomeration of the primary particle.

The invention provides a single battery, a battery device and a power utilization device, the single battery comprises a laminated electrode assembly, the laminated electrode assembly comprises a positive pole piece, an isolating membrane and a negative pole piece which are laminated, the negative pole piece comprises a negative current collector and a negative membrane layer arranged on at least one side of the negative current collector, the positive pole piece comprises a positive pole current collector and a positive pole film layer arranged on at least one side of the positive pole current collector, the positive pole film layer comprises a positive pole active material, the positive pole active material comprises lithium-containing transition metal phosphate particles, the compaction density of the positive pole piece is 2.25-2.65 g / cm < 3 >, and the lithium-containing transition metal phosphate particles are uniformly distributed on the positive pole piece. In a sphericity-like area cumulative distribution curve of particles obtained by a tangent plane of the positive electrode film layer along the thickness direction of the pole piece, the sphericity-like degree LA50 is 0.70-0.75, the isolation film comprises a base film and coatings arranged on two sides of the base film, and a bonding layer in each coating is a porous structure continuous layer and comprises a fluorine-containing polymer. The battery monomer disclosed by the invention can give consideration to both energy density and cycle performance.

The invention provides a battery monomer, a battery device and electric equipment, the battery monomer comprises an electrode assembly and an electrolyte, the electrode assembly comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive current collector and a positive active material layer arranged on at least one side of the positive current collector, and the positive active material layer comprises a positive active material; the positive electrode active material comprises lithium-containing phosphate, and the compaction density of the positive electrode plate is 2.46 g / cm < 3 >-2.8 g / cm < 3 >; the negative pole piece comprises a negative current collector and a negative active material layer arranged on at least one side of the negative current collector, and the compaction density of the negative pole piece is 1.25 g / cm < 3 >-1.5 g / cm < 3 >; the electrolyte comprises fluorine-containing lithium sulfimide and lithium hexafluorophosphate, and based on the total mass of the electrolyte, the ratio of the mass ratio of the fluorine-containing lithium sulfimide to the mass ratio of the lithium hexafluorophosphate is 0.4-0.8; and the mass of the electrolyte corresponding to each Ah of the battery monomer is 2.2-3g.

The invention provides a positive pole piece, a secondary battery and an electronic device. The positive pole piece comprises a positive current collector, a positive material layer and an insulating layer, and the positive material layer and the insulating layer are located on at least one surface of the positive current collector; the positive electrode current collector comprises a main body part and an epitaxial part which are connected with each other, the positive electrode material layer comprises a first positive electrode material layer and a second positive electrode material layer, and the insulating layer comprises a first insulating layer and a second insulating layer; the positive electrode material layer and the first insulating layer are arranged on the main body part; along the thickness direction of the positive pole piece, the first insulating layer is positioned between the second positive pole material layer and the positive pole current collector; the epitaxial part comprises a connecting region and a tab region, and the second insulating layer is arranged in the connecting region; the thickness of the first insulating layer is e [mu] m, the thickness of the second insulating layer is g [mu] m, and 1 < = e < g < = 30. By adopting the positive pole piece disclosed by the invention, the safety performance of the secondary battery can be improved, and the energy density of the secondary battery is considered.

A dual path PLL provides excellent output phase stability over PVT variations, without implementing a high accuracy TDC. A digital integral path employs a binary phase detector, comparing the reference and feedback signals, and an integrator to generate an oscillator control input to lock the long-term output phase to the reference signal. An analog proportional path employs a linear (e.g., edge triggered) phase detector and a charge pump and filter to generate an oscillator control input to mitigate phase noise in the output signal. The feedback signal to the proportional path is delayed, which has the effect of increasing the width of phase error pulses, and moving the charge pump operating point away from the zero point where it generates both positive and negative currents, which are difficult to match. A second linear phase detector in the proportional path compensates for the increased phase error pulse width by comparing the delayed and non-delayed feedback signals, and generating pulses in the opposite direction.

The invention relates to the technical field of lithium ion batteries, in particular to a composite positive pole piece, a preparation method of the composite positive pole piece and a lithium ion battery, the composite positive pole piece comprises a positive current collector, a negative current collector, a positive electrode and a negative electrode, and the positive current collector is provided with two opposite surfaces; the positive electrode active material layer is arranged on at least one surface of the positive electrode current collector; and the solid electrolyte layer is arranged on the positive electrode active material layer. According to the lithium ion battery, the solid electrolyte layer is arranged on the positive active material layer, so that the battery can pass needling, overcharge and short-circuit test inspection, and the use safety of the lithium ion battery is comprehensively improved.

The invention provides a battery monomer, a battery device, a power utilization device and an energy storage device. The battery monomer comprises a laminated battery cell, the laminated battery cell comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive current collector and a positive film layer arranged on at least one side of the positive current collector, and the positive film layer comprises lithium-containing transition metal phosphate particles of which at least part of the surface is provided with a carbon material; in a cumulative distribution curve of a graphitization degree C value obtained by the positive electrode film layer in a surface scanning mode of a laser microscopic confocal Raman spectrometer, the median C50 of the graphitization degree is 0.95-1.20, the graphitization degree C value is IG / ID, IG represents the G peak intensity of a Raman spectrum at 1580 + / -100 cm <-1 >, ID represents the D peak intensity of the Raman spectrum at 1350 + / -100 cm <-1 >, and when the battery monomer is in a full discharge state, the battery monomer is in a non-full discharge state. And the compaction density of the positive pole piece is 2.3-2.6 g / cm < 3 >. The battery monomer provided by the invention has high capacity and good cycle performance.

The embodiment of the utility model provides a battery monomer, a battery device, an energy storage device and a power utilization device, and belongs to the technical field of batteries. The battery monomer comprises a shell and an electrode assembly, the electrode assembly is accommodated in the shell and comprises a pole piece and a diaphragm, a positive pole piece in the pole piece comprises a positive current collector body and a positive pole lug connected with the positive current collector body, a coating layer, an insulating layer and a cementing layer are arranged on the surface of the positive current collector body, and the insulating layer is arranged on the surface of the coating layer. And the insulating layer positioned between the coating layer and the positive pole lug is provided with the cementing layer bonded with the diaphragm. According to the invention, the condition that the non-welded area of the lug root part is pressed between the positive pole piece and the negative pole piece can be reduced.

The invention discloses a battery monomer, a preparation method thereof and an electric device. The battery monomer comprises a positive electrode plate, the positive electrode plate comprises a positive electrode current collector and a positive electrode film layer, the positive electrode film layer is arranged on at least one side surface of the positive electrode current collector, and the positive electrode film layer comprises a first metal oxide, a second metal oxide and a surfactant; the chemical formula of the first metal oxide meets Li5MO4, and M comprises one or more of Fe, Cr, V and Mo; the chemical formula of the second metal oxide meets LiaNbO2, and a is bgt; 1, 1lt; a < = 2, 0lt; b is less than or equal to 1, and N comprises one or more of Cu, Co, Mg, Zn, Mn, Al, Ni, Zr, Ti and Fe; the surfactant comprises one or more of phosphate ester, acrylic ester, hydrogenated butyronitrile and polyvinylpyrrolidone, the first-circle charging capacity of the battery monomer can be improved, and gas production in the battery monomer can be reduced.