70results about How to "Reduce DC internal resistance" patented technology

The invention belongs to the field of lithium batteries, in particular to a low-temperature lithium ion battery. The positive electrode sheet comprises a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer comprises 4.4 V lithium cobaltate material, a positive electrode conductive agent and a positive electrode binder. The negative electrode sheet comprises a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer comprises a hard carbon coatedsecondary particle artificial graphite material, a negative electrode conductive agent, a dispersant and a negative electrode binder. The electrolyte comprises 10-20% of lithium hexafluorophosphate,10-20% of ethyl propionate, 10-20% of diethyl carbonate, 15-30% of vinyl carbonate, 15-30% of propyl propionate, 3-10% of fluorovinyl carbonate, 2-3% of propylene sulfite, 0.5-2.5% of ethylene glycolmonobutyl ether and 0.5-2.5% of 2, 2'-dithiopyridine. Compared with the batteries in the prior art, the lithium ion battery has good charging and discharging performance and higher energy density under low temperature condition.

The invention discloses a composite conductive agent and a preparation method thereof, and a lithium-ion battery positive electrode. The composite conductive agent comprises following components by weight percentage: 0.5-1.6% of conductive carbon black, 0.28-0.56% of carbon nanotubes, 0.12-0.24% of graphene, 0.5-0.8% of dispersing agent, and 97.5-97.9% of solvent. The preparation method of the composite conductive agent comprises following steps: 1) preparing composite powder according to a formula amount; 2) adding the composite powder into the solvent to obtain a mixture; and 3) performing ultrasonic dispersion on the mixture to obtain the composite conductive agent. The composite conductive agent is advantageous in that the composite conductive agent comprises the conductive carbon black, the carbon nano-tubes and the graphene, the particle size of the conductive carbon black is small, the conductive carbon black is in point-shaped connection, the carbon nanotubes are in linear connection, the graphene is in planar connection, a coupling effect is fully produced among the conductive carbon black, the carbon nanotubes and the graphene, the gram volume of the active substance of the positive electrode is improved, and the rate and the circulation property of the lithium iron phosphate battery are optimized.

The invention belongs to the field of batteries and relates to an electrode pole sheet and an electrochemical device. The electrode pole sheet comprises a current collector and an electrode active material layer arranged on at least one surface of the current collector; the current collector comprises a supporting layer and a conductive layer arranged on at least one surface of the supporting layer; the single-surface thickness D2 of the conductive layer meets a relation that D2 is more than or equal to 30nm and less than or equal to 3 micrometers; the electrode active material layer comprisesan electrode active material, a binder and a conductive agent; the conductive agent in the electrode active material layer is non-uniformly distributed in a thickness direction; and based on the total weight of the electrode active material layer, the weight percentage of the conductive agent in the inner side area of the electrode active material layer is higher than the weight percentage of theconductive agent in the outer side area of the electrode active material layer. The electrode pole sheet has good machinability; and the electrochemical device comprising the electrode pole sheet hashigh energy density, good electrical performance and long-term reliability.

The invention provides an integrated double-layer vertical wound inductor, which comprises a magnetic body, a hollow coil and a covered electrode, wherein the magnetic body is formed by pressing magnetic powder; the hollow coil is embedded into the magnetic powder and an integrated structure of the hollow coil and the magnetic body is manufactured through high pressure; the end part of the hollow coil is exposed out of the magnetic body; and the surface of one side, out of which the hollow coil is exposed, of the magnetic body is covered with the covered electrode. Compared with the prior art, the integrated double-layer vertical wound inductor has the advantages of being small in volume, good in performance, high in performance-volume ratio and beneficial to high-density installation, and the integration level of a client is improved. A manufacturing method of the integrated double-layer vertical wound inductor comprises the following steps of (1) carrying out compression molding; (2) carrying out multi-stage temperature sintering and solidifying; (3) adding an anti-oxidation coating; (4) grinding the end surfaces of two sides from which a lead of the hollow coil extends outside; (5) forming symmetrical boning pad positions on the upper surface and the lower surface of a semi-finished product; and (6) arranging the covered electrode.

The invention relates to the field of batteries, in particular to a positive pole piece and an electrochemical device. The positive pole piece comprises a current collector and an electrode active material layer arranged on at least one surface of the current collector, wherein the current collector comprises a support layer and a conductive layer arranged on at least one surface of the support layer, the thickness D2 of a single surface of the conductive layer is more than or equal to 30nm and less than or equal to 3mu m, the thickness D1 of the support layer is more than or equal to 1mu m and less than or equal to 30mu m, and the support layer is made of a high polymer material or a high polymer composite material; the electrode active material layer includes an electrode active material, a binder, and a conductive agent, and the electrode active material includes a small-particle active material having an average particle diameter D50 of 1.0 [mu] m to 7.0 [mu] m and a large-particleactive material having an average particle diameter D50 of 7.1 [mu] m to 20.0 [mu] m. The electrochemical device comprising the positive pole piece has high energy density, good safety performance (especially nail penetrating safety performance) and electrochemical performance.

The invention belongs to the field of batteries and relates to an electrode pole sheet and an electrochemical device. The electrode pole sheet comprises a current collector and an electrode active material layer arranged on at least one surface of the current collector; the current collector comprises a supporting layer and a conductive layer arranged on at least one surface of the supporting layer; the single-surface thickness D2 of the conductive layer meets a relation that D2 is more than or equal to 30nm and less than or equal to 3 micrometers; the electrode active material layer comprisesan electrode active material, a binder and a conductive agent; the conductive agent in the electrode active material layer is non-uniformly distributed in a thickness direction; based on the total weight of the electrode active material layer, the weight percentage of the conductive agent in the inner side area of the electrode active material layer is higher than the weight percentage of the conductive agent in the outer side area of the electrode active material layer; and the conductive agent in the inner side area of the electrode active material layer contains an aqueous binder. The electrode pole sheet has good machinability; and the electrochemical device comprising the electrode pole sheet has high energy density, good electrical performance and long-term reliability.

The invention discloses a secondary battery and an electronic device, and belongs to the technical field of batteries. The secondary battery comprises a positive pole piece, wherein the positive pole piece comprises a current collector and a positive active material layer; the positive electrode active material layer comprises a positive electrode active material and a carbon material; the carbon material comprises a carbon nanotube bundle with the length-diameter ratio of 2.5 to 100; the carbon nano tube bundle comprises a plurality of first carbon nano single tubes. The carbon nanotube bundle can reduce the initial internal resistance of the battery, guarantee the improvement of a conductive network in the circulation process, effectively reduce the increase of the internal resistance, and improve the charging speed.

The invention discloses a lithium ion battery diaphragm as well as a lithium ion battery. The lithium ion battery diaphragm includes a diaphragm base material and non-symmetric organic coatings comprising a first organic coating and a second organic coating, which are formed by respectively coating both surfaces of the diaphragm base material with organic polymers; herein, the first organic coating and the second organic coating include non-symmetric organic coatings, which are prepared from the same organic polymer but are in different surface densities, or include non-symmetric organic coatings, which are prepared from different organic polymers but are in the same surface densities, or include non-symmetric organic coatings, which are prepared from different organic polymers and are indifferent surface densities. In the invention, by coating the both surface of the diaphragm base material with the non-symmetric organic coatings, direct current internal resistance of the lithium ionbattery is reduced on the basis of satisfying the adhesivity between positive and negative plates of the lithium ion battery, so that the lithium ion battery has better performances.

The invention belongs to the field of preparation of positive electrode materials for lithium ion batteries, and in particular relates to a directionally arranged graphene-coated positive electrode material for a lithium ion battery. According to the directionally arranged graphene-coated positive electrode material for the lithium ion battery, the preparation material comprises an A component, aB component and a C component; the A component comprises a fluorine-containing organic substance and an organic solvent; the B component comprises a fluorine-containing organic substance, an organic solvent and graphene; and the C component comprises a positive electrode active material.

The invention belongs to the field of batteries and relates to an electrode pole sheet and an electrochemical device. The electrode pole sheet comprises a current collector and an electrode active material layer arranged on at least one surface of the current collector; the current collector comprises a supporting layer and a conductive layer arranged on at least one surface of the supporting layer; the single-surface thickness D2 of the conductive layer meets a relation that D2 is more than or equal to 30nm and less than or equal to 3 micrometers; the electrode active material layer comprisesan electrode active material, a binder and a conductive agent; the conductive agent in the electrode active material layer is non-uniformly distributed in a thickness direction; based on the total weight of the electrode active material layer, the weight percentage of the conductive agent in the inner side area of the electrode active material layer is higher than the weight percentage of the conductive agent in the outer side area of the electrode active material layer; and the conductive agent in the inner side area of the electrode active material layer contains an acrylic acid group/acrylate group aqueous binder. The electrode pole sheet has good machinability; and the electrochemical device comprising the electrode pole sheet has high energy density, good electrical performance and long-term reliability.

The invention provides a lithium ion battery positive pole piece, which comprises a positive current collector, a conductive coating layer and an active slurry layer, wherein the conductive coating layer and the active slurry layer are sequentially coated on the positive current collector, and the active slurry layer comprises, by mass, 95% of a LiFePO4 active substance, 2.8% of a conductive agent and 2.2% of a binder; the conductive coating layer comprises the following components in percentage by mass: 10% of a conductive agent, 2% of a binder, 1% of ethanol, 1% of acetone and 86% of deionized water; the binder is polyvinylidene fluoride, the conductive agent is conductive carbon black, and the positive active substance is LiFePO4. The preparation method is simple, the conductivity of the pole piece can be effectively improved, the lithium ion transfer impedance in the battery is obviously reduced, the direct-current internal resistance of the battery is obviously reduced, and the cycling stability of the battery can be improved.

The invention relates to the field of batteries, in particular to an electrode plate and an electrochemical device. The electrode plate comprises a current collector and an electrode active material layer arranged on at least one surface of the current collector, wherein the current collector comprises a supporting layer and a conductive layer arranged on at least one surface of the supporting layer, the thickness D2 of a single surface of the conductive layer is greater than or equal to 30nm and less than or equal to 3mu m, the supporting layer is made of a high polymer material or a high polymer composite material, and the thickness D1 of the supporting layer is greater than or equal to 1mu m and less than or equal to 30mu m; wherein the electrode active material layer includes an electrode active material, a binder, and a conductive agent, and the coated electrode active material layer includes three regions based on a compaction density when viewed from a width direction of a coated surface of the electrode sheet, and a compaction density of a middle region is higher than compaction densities of both side regions. The electrode pole piece and the electrochemical device have high energy density and good electrical performance and safety.

The invention belongs to the technical field of lithium ion battery positive electrode materials, and particularly provides a preparation method of a graphene-coated positive electrode material of a lithium ion battery. The invention provides the preparation method of a directionally-arranged graphene-coated positive electrode material of the lithium ion battery. The preparation method comprises the following steps: preparing mixed slurry, and performing drying and compounding, wherein the raw materials of the mixed slurry comprise a binder, graphene and a positive electrode active substance;spray drying is utilized in the drying process, wherein the temperature of spray drying is 120-300 DEG C.

Electrolyte and application thereof are disclosed. The invention discloses an electrolyte for a lithium-ion battery and the lithium-ion battery. The electrolyte for the lithium-ion battery comprises amain lithium salt, an auxiliary lithium salt and an organic solvent, wherein the main lithium salt is tris(trifluoromethylsulfonyl) methyl lithium (LiC(SO2CF3)3), and the auxiliary lithium salt comprises lithium oxalyldifluoroborate(LiODFB) and lithium hexafluorophosphate(LiPF6). The electrolyte takes tri(trifluoromethylsulfonyl) methyl lithium as a main lithium salt, so that the high and low temperature performance of the battery can be obviously improved, the rate capability and the cycling stability of the battery are improved, and the direct-current internal resistance of the battery is reduced.

The invention relates to a preparation method and application of lignin-based hard carbon, and belongs to the technical field of energy storage. The preparation method of the lignin-based hard carboncomprises the following steps: pretreating lignin, and dissolving the pretreated lignin in an organic solvent solution to form a lignin nanoparticle precursor solution; drying the lignin nanoparticleprecursor solution to prepare a lignin nanoparticle precursor; and carrying out vacuum carbonization on the lignin nanoparticle precursor to prepare the lignin-based hard carbon. The lignin-based hardcarbon disclosed by the invention is simple in preparation process, strong in pulse discharge capability, good in low-temperature performance and low in direct-current internal resistance when beingused as a negative electrode material of a lithium ion capacitor.

The invention relates to an oily binder and application thereof. The oily binder comprises at least one of oily polyacrylic acid, oily polyacrylate, oily styrene acrylate, oily polyacrylonitrile, oilypolyacrylamide, oily polyimide and oily polyamideimide, and the molecular weight of the oily binder is selected from 5W-200W. The oily binder is used for replacing a traditional water-based binder tobe used for negative electrode slurry, and the problems that water-based negative electrode slurry is uneven in dispersion and large in number of coating particles, and the water-based binder floatsupwards and sticks to a roller in a cold pressing mode are effectively solved. Compared with a traditional water-based adhesive, a battery cell obtained by the oily adhesive has the characteristics oflow direct-current internal resistance, good quick-charge performance, small quick-charge temperature rise, few side reactions and long cycle life of the battery cell. Compared with oily polyvinylidene fluoride serving as a binder, the oily binder disclosed by the invention has the advantage that the obtained battery cell has higher energy density.

The present invention relates to a battery module including an ultra-long battery cell. The battery module according to the present invention includes: ultra-long battery cells each having opposite ends to which a plurality of electrode tabs are connected; a battery stack formed by stacking the battery cells; end-side bus bar assemblies formed at opposite ends of the battery stack, respectively, and electrically connecting the electrode tabs of the battery cells; transverse bus bar assemblies each electrically connecting electrode tabs connected to opposite ends of an uppermost battery cell ora lowermost battery cell in the battery stack; and a case accommodating the battery stack, the end-side bus bar assemblies, and the transverse bus bar assemblies. With the battery module according tothe present invention, it is possible to suppress an increase in internal resistance of the ultra-long battery cell and heating, and to improve structural stability.