8results about How to "Reduce DC internal resistance" patented technology

The application discloses a negative pole piece and a lithium ion battery, and relates to the technical field of batteries, and specifically discloses a negative pole piece and a lithium ion battery. The negative pole piece comprises a current collector, a first coating layer and a second coating layer which are stacked on at least one side of the current collector; the first coating layer and the second coating layer each comprise a negative active material, a first binder, a second binder, a first conductive agent and a second conductive agent; and the preparation of the negative pole piece satisfies the following conditions: 2≤C2 / C1≤4 and 1.05≤X / Y≤1.25, wherein C1 and C2 are the mass proportions of the first conductive agent in the first coating layer and the second coating layer respectively, and X and Y are the solid contents of the first coating layer slurry and the second coating layer slurry respectively. According to the application, the solid content of the slurry, the proportions of different active materials and conductive agents are designed and controlled in the double-coating pole piece, and the designed proportions satisfy a certain functional relationship, so that the ion conductivity of the battery can be effectively improved while the high conductivity of the pole piece is maintained, the direct-current internal resistance of the pole piece in the charging and discharging process is reduced, the rate charging and discharging performance is improved, and the lithium precipitation window is widened.

The application provides a modified conductive carbon, a slurry, a positive electrode, a battery and a preparation method thereof, the modified conductive carbon, wherein 0.05wt%-0.1wt% of F elements are doped. Compared with unmodified conductive carbon, the modified conductive carbon has an open pore structure. The modified conductive carbon is prepared by fluorination treatment of graphene oxide with sodium 2,2,3,3-tetrafluoropropionate as a fluorine source and phosphoric acid immersion treatment. The application improves the problem of water introduction in the positive electrode slurry, can stabilize the viscosity of the positive electrode slurry in air, and improves the electrical properties such as the resistance, charge and discharge life of the battery, and improves the chemical stability of the positive electrode slurry of the sodium ion battery in air.

The embodiment of the utility model provides a diaphragm, an electrode assembly, a battery and electric equipment. The diaphragm comprises a structural layer, the structural layer comprises a base membrane and a solid electrolyte layer, and the solid electrolyte layer is arranged on at least one side of the base membrane. The number of the bonding layers is two, the two bonding layers are arranged on the two sides of the structural layer respectively, each bonding layer comprises a plurality of cold-pressing micelles, and the cold-pressing micelles are distributed in a dot matrix mode. The arrangement of the solid electrolyte layer and the cold-pressed micelles in dot matrix distribution eliminates the impedance influence of the cold-pressed glue on the diaphragm, so that the direct-current internal resistance of the battery adopting the diaphragm is reduced, and the production and processing cost of the battery adopting the diaphragm is reduced at the same time.

The present application relates to an electrochemical device and an electronic device comprising the same. The electrochemical device of the present application comprises: a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a positive electrode current collector and a positive electrode active material layer on the positive electrode current collector, the positive electrode active material layer comprising a positive electrode active material, wherein the mass percentage of the positive electrode active material is M% based on the mass of the positive electrode active material layer, M ranges from 95 to 99, and the cracking width of the surface of the positive electrode active material layer is W mm, wherein M and W satisfy: M / W≥47.5. The electrochemical device provided by the present application has reduced direct current internal resistance and improved capacity retention rate, low temperature performance and floating performance.

The application provides a battery cell, which comprises a positive electrode sheet, a separator and a negative electrode sheet; the positive electrode sheet comprises a positive electrode current collector and a positive electrode active material layer; the positive electrode active material layer comprises a positive electrode active material, the positive electrode active material comprises lithium cobaltate, the particle size of the lithium cobaltate is d1, the unit is mu m, and the value range of d1 is 0 mu m < d1 <= 2 mu m; the negative electrode sheet comprises a negative electrode current collector and a negative electrode active material layer coated on the surface of the negative electrode current collector; the thickness of the negative electrode current collector is 7 mu m-11 mu m; the negative electrode active material layer comprises a second binder, and the second binder comprises a CMC compound; by introducing lithium cobaltate particles with a particle size of 0-2 mu m into the positive electrode sheet, adopting a negative electrode current collector with a thickness of 7 mu m-11 mu m, and simultaneously adopting a CMC compound in the negative electrode active material layer, the direct current resistance of the battery can be small, the heat generation in the cycle process can be reduced, the by-products caused by temperature rise can be relatively reduced, and the long cycle performance of the battery cell can be ensured.

The invention provides modified conductive carbon, slurry, a positive electrode, a battery and a preparation method of the modified conductive carbon, and the modified conductive carbon is doped with 0.05 wt%-0.1 wt% of an F element. Compared with unmodified conductive carbon, the modified conductive carbon has an open pore structure. The modified conductive carbon is prepared by using 2, 2, 3, 3-tetrafluoropropionate sodium as a fluorine source to carry out fluorination treatment on graphene oxide and carrying out phosphoric acid soaking treatment. The problem of water introduction in the positive electrode slurry is improved, the viscosity of the positive electrode slurry in air can be stabilized, the electrical properties such as resistance and charge-discharge life of the battery are improved, and the chemical stability of the positive electrode slurry of the sodium-ion battery in air is improved.

The invention discloses a secondary battery and an electric device, and belongs to the technical field of secondary batteries. The secondary battery comprises a positive plate, a negative plate, a diaphragm and an electrolyte, the positive plate comprises a positive material layer, the positive material layer comprises a positive material, the positive material comprises a layered transition metal oxide, and the electrolyte comprises a cyclic sulfate compound. According to the present invention, by comprehensively regulating and controlling the unit cell volume a3 of the positive electrode material when the secondary battery is charged to 90% SOC, the amount of Fe < 3 + > produced by the reaction of the positive plate and ferrocene (represented by the concentration bmmol / L of Fe < 3 + > in the solution after the reaction), and the tortuosity c of the positive plate, the a * c / b is within the suitable range, such that the interface activity of the positive electrode material can be reduced, the stability of the positive electrode material can be improved, and the battery performance can be further improved. Gas produced in the battery is reduced, and the safety of the battery is improved; the transmission path of lithium ions can be shortened, and the direct-current internal resistance of the battery is reduced.

The embodiment of the invention provides a biomass charcoal negative electrode material modification method and system, and the method comprises the steps: pretreating a biomass raw material for removing impurities and controlling the particle size; pyrolyzing and carbonizing the pretreated biomass raw material to obtain biomass powder, heating to a carbonization temperature at a controllable heating rate under the protection of inert gas, and preserving heat to form primary biochar; mixing the primary biochar with an activator, and performing chemical activation treatment at an activation temperature to regulate and control a pore structure and surface properties and generate an activated product; neutralizing the activated product by using an acid solution and dissolving residual alkaline substances for post-treatment of the activated product; and mixing and drying an anchoring agent and the post-treated activation product to obtain the modified biomass charcoal negative electrode material, and the anchoring agent is selected from a lithium polysulfide compound and is used for anchoring transition metal ions in an electrolyte. According to the invention, the negative electrode interface is protected from being damaged by transition metal ions in electrochemical energy storage.