155results about How to "Excellent liquid retention" patented technology

The invention discloses a lithium ion battery composite diaphragm and a preparation method and an application thereof, belonging to the technical field of lithium ion batteries. The composite diaphragm comprises a polyolefin microporous membrane, a polymer microsphere based coating on one side surface of the polyolefin microporous membrane, and an inorganic ceramic-based coating on the other side surface of the polyolefin microporous membrane. The lithium ion battery composite diaphragm has good air permeability, liquid retaining capability and high-temperature resistance and can remarkably improve the security and the circulation property of the battery. The melting point or softening point of the polymer microsphere-based coating in the composite diaphragm is 90-140 DEG C, and when the temperature of the battery is increased, the polymer microsphere based coating is molten or swelled within a short time, then the apertures of the polyolefin microporous membrane are blocked rapidly, the thermal turn-off effect of the diaphragm is achieved, a lithium ion conveying channel is cut off, and short circuit inside the battery is prevented; meanwhile as ceramic grains inside the inorganic ceramic-based coating have the high-temperature resistance property, the polyolefin microporous membrane is effectively prevented from shrinkage, and the situation that positive and negative films directly come into contact to cause short circuit of the battery.

The invention relates to a novel ceramic coating polyolefin composite film which comprises a polyolefin substrate with micro pores, wherein one side or both sides of the polyolefin substrate is/are compounded with ceramic coating(s); the ceramic coating comprises porous ceramic particles, an inorganic filler and an adhesive. The invention also relates to a method for preparing the novel ceramic coating polyolefin composite film. The method comprises the following steps: a, dissolving the adhesive in a solvent, thereby preparing an adhesive solution; b, adding the porous ceramic particles and the functional inorganic filler into the adhesion solution prepared in the step a, and performing dispersing treatment, thereby preparing coating slurry; and c, coating one or two surfaces of the polyolefin substrate with the coating slurry prepared in the step b, and drying and curing to prepare the product. The novel functional composite film has high liquid absorption and retention performance, has the functions of reducing harmful gases inside a battery, improving the performance of the battery and prolonging the service life of the battery, and has the safety characteristics of low closed pore temperature, high melting temperature and low hot-shrinkage rate.

The invention discloses a nitride ceramic coating applied to a lithium ion battery. The nitride ceramic coating consists of the following components in parts by weight: 2-10 parts of adhesive, 10-40 parts of nitride ceramic particles, 0.5-3 parts of thickening agent, 0.05-2 percent of dispersing agent and the balance of solvent. The nitride ceramic coating is prepared by the following steps: (1) preparing slurry, namely uniformly mixing and stirring the solvent, the dispersing agent and the thickening agent, standing, defoaming, adding the nitride ceramic particles, uniformly dispersing and forming slurry A; (2) dispersing at high speed, namely dispersing the slurry A at high speed, then adding the additive, uniformly stirring, performing vacuum defoaming, and screening to form slurry B; (3) coating, namely coating the slurry B on an edge of the anode and/or the surface of the cathode and/or a diaphragm in the lithium ion battery, and drying at the temperature of 60-120 DEG C. According to the nitride ceramic coating, the liquid absorption capacity and liquid retaining capacity of the diaphragm or the pole piece can be effectively improved, the hydrofluoric acid resistance and thermal shock resistance of the pole piece or the diaphragm are improved, and a better heat barrier effect is achieved.

The invention discloses an artificial graphite negative electrode material for a lithium ion battery and a preparation method thereof. The preparation method for the artificial graphite negative electrode material comprises the following steps: preparing powder, adding a binder and/or a crystal nucleus-induced growth additive, kneading, carrying out compression molding, thermally roasting, carrying out nodulizing shaping and/or fusing, carrying out ultrahigh-temperature graphitization, screening, removing magnetism and screening. The preparation method disclosed by the invention is simple to operate, easy to control, lower in production cost and suitable for industrial production. The prepared artificial graphite negative electrode material has high graphitization degree, high compactness, high capacity, high coulombic efficiency, high conductivity and high multiplying power, and can be used for the lithium ion battery.

This invention discloses pole plates of Li ionic cells, in which, a micro-porous film is set on the pole plate with PVDF as the matrix and chemical gel formed by chimical cross-link is set in the micro-porous film.This invention also discloses a Li-ionic cell core with said pole plates and a preparation method including: the PVDF film forming chemical gel inside by irradiation and cross-link has the heat contraction rate of nearly zero under 100-220deg.C, which can prevent electronic short circuit of positive and negative pole plates caused by over contraction of intensified switchable Polyolefin micro-hole septums under high temperature when being coated on the pole plates.

The invention provides a preparation method of composite graphite to overcome the problems that the composite graphite prepared by the method in the prior art is low in energy density, poor in high-rate charge and discharge properties and high in expansion rate in the charging and discharging processes. The preparation method comprises the following steps: (S1) providing ultrafine carbon powder, wherein the ultrafine carbon powder comprises green coke and/or mesophase carbon green microspheres; (S2) mixing the ultrafine carbon powder with a binder to obtain a mixture A, mixing the mixture A with a catalyst to obtain a mixture B, and then carrying out combined treatment on the mixture B to obtain a precursor; (S3) carrying out graphitizing treatment on the precursor to obtain a semi-finished product; and (S4) crushing, spheroidizing, wrapping and sieving the semi-finished product to obtain the composite graphite. Meanwhile, the invention further discloses the composite graphite prepared by the method and a lithium ion battery. The composite graphite provided by the invention is high in energy density, good in liquid absorption and retention properties, good in isotropic property, good in high-rate charge and discharge properties and low expansion rate in the charging and discharging processes.

The invention provides a low-temperature type lithium ion battery with high voltage and high volume energy density. The low-temperature type lithium ion battery comprises a cathode, an anode, an isolating membrane and an electrolyte solution, wherein the isolating membrane is formed by coating polyvinylidene fluoride-hexafluoropropylene copolymer coatings on both sides of a polyolefin isolating membrane substrate. According to the low-temperature type lithium ion battery with high voltage and high volume energy density provided by the invention, the polyvinylidene fluoride-hexafluoropropylene copolymer coated on the surfaces of the isolating membrane can polymerize with polyvinylidene fluoride in positive and negative pole pieces, so that the cathode and the anode are tightly attached with the isolating membrane together, the expansion of the cathode and the anode is reduced, the inner volume of the battery is further reduced, and the energy density is improved; moreover, the polyvinylidene fluoride on the surfaces of the isolating membrane has good electrolyte retention, and is matched with the low-temperature type lithium ion electrolyte solution and good cathode and anode space conducting network, so that lithium ions can be relatively high in diffusion and disembedding speed between the electrolyte solution and the cathode and the anode under low temperature, and the discharging capacity of greater than or equal to 90% at -20 DEG C can be realized.

The invention provides a diaphragm of a lithium battery and a preparation method thereof. The diaphragm of the lithium battery comprises a base diaphragm, a ceramic coating and a hot melted polymer coating. The ceramic coating and the hot melted polymer coating are located on the same side of the base diaphragm, and the ceramic coating comprises a ceramic particle material and a first adhesive; the hot melted polymer coating comprises hot melted polymer material particles and a second adhesive. The problem of thermal closing and thermal contraction of the diaphragm is solved.

The invention relates to a novel battery, which solves technical problems of a conventional chargeable battery, including high cost, low specific energy, short service life and serious pollution. The novel battery comprises a battery anode, a battery cathode, an electrolyte and a diaphragm. The battery anode is made of manganese dioxide/polyaniline/carbon composite materials. The electrolyte is weakly acidic. The novel battery can be widely applied to the field of batteries.

The invention discloses a lithium ion battery electrode slice which comprises binder I. The binder I is made from any one of or a mixture of at least two of maleic anhydride grafted polyvinylidene fluoride, polymethyl methacrylate and polyethylene oxide. The electrode slice can be a positive electrode slice or a negative electrode slice. The invention further discloses a preparation method of the positive electrode slice. The preparation method includes the following steps: (1), binder II is added into dissolvent, and mixed to be dissolved in the dissolvent, and then the binder I is added into the dissolvent to prepare and obtain binder mother solution; (2), conductive agent and positive electrode active material are added into the binder mother solution to prepare and obtain sizing agent, and then coating and drying are performed to prepare and obtain the lithium ion battery positive electrode slice. The preparation process is simple, the production efficiency is high, the lithium ion battery positive electrode slice is compatible with existing equipment for battery preparation, industrial and large batch production can be achieved, and the prepared lithium ion battery positive electrode slice is good in machinability and liquid retainability.

The invention relates to a high-capacity and high-compaction artificial graphite negative electrode material, a preparation method thereof and a lithium ion battery. The preparation method comprises the steps of selecting at least two of pitch coke, petroleum coke and needle coke as graphite raw materials, and uniformly mixing with a coating agent to obtain a mixed material; and performing graphitization on the mixed material at 3,000-3,300 DEG C under a protection atmosphere to obtain the high-capacity and high-compaction artificial graphite negative electrode material. According to the preparation method of the high-capacity and high-compaction artificial graphite negative electrode material, the problem that the material is easy to press excessively due to inappropriate selection of theraw material cokes is solved by selection and matching of raw material cokes with different hardness, and the prepared graphite negative electrode material has appropriate hardness and rebound rate.A pole plate prepared from the artificial graphite negative electrode material is high in compaction density, an electrolyte is rapidly immersed, and the electrochemical performance of the lithium ionbattery is prolonged.

In an electric storage device, lithium electrodes are disposed on respective outermost portions of an electrode laminated unit in which a positive electrode and a negative electrode are laminated alternately via positive/negative electrode separators. The lithium electrode includes lithium metal serving as a lithium ion supply source, and a lithium electrode separator (a non-woven fabric separator) constituted by a non-woven fabric that satisfies the following conditions: (a) an average fiber diameter of 0.1 μm to 10 μm; and (b) a thickness of 5 μm to 500 μm is provided. By forming the lithium electrode separator that contacts the lithium electrode including the lithium ion supply source from a non-woven fabric in this manner, a dramatic improvement can be achieved in the cycle characteristic of the electric storage device.

The invention provides a septum used in a battery which is suitable to be used in nickel-cadmium battery, nickel-zinc battery, nickel-hydrogen battery, and other alkaline rechargeable batteries. The septum has excellent tear strength, and using a surfactant makes for reducing short circuit incidence rate. The septum is made of non-woven fabric which is processed by hydrophilization. The septum used in the battery is formed by a core-sheath type complex fibernon-woven fabric, with polypropylene as composition of a core and polyethylene as composition of a sheath. The septum is characterized in that a ratio ([beta/alpha]) of a sectional area ([beta]) of polypropylene and a sectional area ([alpha])ofpolyethylene is larger than 50/50 and is lower than 90/10. In a DSC curve obtained by differential scanning thermal analysis of the septum used in the battery, a ratio (A/B) of fusing peak area (A) from the polyethylene on a low-melting-point side and fusing peak area (B) from the polypropylene on a high-melting-point side is larger than 0.15 and lower than 1.20.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a battery diaphragm. The battery diaphragm includes a diaphragm base layer and a hot-melt polymer layer arranged on at least one surface of the diaphragm base layer. The diaphragm base layer includes at least one of glass fibers and ceramic fibers, and first adhesive. The hot-melt polymer layer includes a hot-melt polymer and second adhesive. Compared with the prior art, the diaphragm has better thermal stability, higher mechanical strength and stronger liquid retention and absorption capacity. In addition, the invention provides a preparation method of the battery diaphragm and a lithium ion battery containing the diaphragm.

The present invention discloses a preparation method of a material for abdominal wall defect intraperitoneal repair, and the obtained material thereof. The preparation method comprises: 1, preparing a quaternized bacterial cellulose solution; 2, carrying out polydopamine modification on a polypropylene mesh sheet; and 3, coating the quaternized bacterial cellulose solution on the obtained polypropylene mesh sheet. The present invention further provides the material used for the abdominal wall defect intraperitoneal repair and obtained through the process. The obtained material of the present invention has characteristics of good mechanical property, good biocompatibility, good adhesion resistance and good antibacterial property.

The invention discloses a bacterial cellulose/fabric laminated composite material and a preparation method thereof. The preparation method comprises the following steps: (1) inoculating acetobacter xylinum into a fluid medium for enlarged cultivation; (2) appropriately cutting a fabric and treating with low-temperature oxygen plasmas or aqueous alkali, or through ultraviolet light surface grafting; and sterilizing and then drying the fabric; (3) arranging the medium containing floccules into a culture dish, spreading the treated fabric on bacterium solution, adding the medium containing floccules into the fabric, and arranging in a biochemical incubator until the laminated composite material is formed; and (4) soaking the composite material with deionized water at normal temperature, soaking the composite material with sodium hydroxide solution for two days, and soaking the composite material with deionized water until the composite material is neutral. The composite material is formed at a time, the appetency of the single fabric and the texture is improved, and the water retainability and the transdermal absorption ratio of the fabric are improved; meanwhile, the operation is convenient and simple and the using efficacy is greatly improved.

The present invention relates to one kind of slurry paper for no-mercury Zn-Mn cell with polymer electrolyte. The slurry paper includes base paper and slurry, and the slurry consists of one kind of polymer gel prepared with coordination ion liquid and organic mercury-replacing buffer liquid. The coordination ion liquid is prepared with urea, thiourea, zinc chloride and ammonium chloride; and the polymer gel is prepared with coordination ion liquid, PVA, PAM, PEG and crosslinking starch in certain proportion. The no-mercury Zn-Mn cell with polymer electrolyte can decrease the internal resistance of cell, improve dynamic discharge performance of cell, prolong the maintenance time and avoid environmental pollution caused by mercury.

The invention relates to a secondary lithium ion battery and a preparation method thereof. The secondary lithium ion battery comprises an anode, a cathode, a diaphragm and a non-water electrolyte, wherein the surface of the cathode is coated with a mixture containing an anode exchange mateiral and an inorganic material, the anode exchange material is aluminosilicate or phosphoaluminate containing anions of lithium, sodium and ammonium, the inorganic material is Al2O3 or SiO2, and in addition, the mass ratio of the anode exchange material to the inorganic material is (1:50)-(10:1). Compared with the traditional lithium ion battery, the lithium ion battery disclosed by the invention is obviously promoted in safety performance and cycle performance, and is long service life and suitable for large-scale industrial production.