95results about How to "Improve thermal safety" patented technology

Disclosed is an organic / inorganic composite porous film comprising: (a) inorganic particles; and (b) a binder polymer coating layer formed partially or totally on surfaces of the inorganic particles, wherein the inorganic particles are interconnected among themselves and are fixed by the binder polymer, and interstitial volumes among the inorganic particles form a micropore structure. A method for manufacturing the same film and an electrochemical device including the same film are also disclosed. An electrochemical device comprising the organic / inorganic composite porous film shows improved safety and quality.

Disclosed is an organic / inorganic composite porous film comprising: (a) a porous substrate having pores; and (b) an active layer formed by coating a surface of the substrate or a part of the pores in the substrate with a mixture of inorganic particles and a binder polymer, wherein the inorganic particles in the active layer are interconnected among themselves and are fixed by the binder polymer, and interstitial volumes among the inorganic particles form a pore structure. A method for manufacturing the same film and an electrochemical device including the same film are also disclosed. An electrochemical device comprising the organic / inorganic composite porous film shows improved safety and quality, simultaneously.

Disclosed is an organic / inorganic composite porous separator comprising: (a) a polyolefin-based separator substrate; and (b) an active layer formed by coating at least one region selected from the group consisting of a surface of the substrate and a part of pores present in the substrate with a mixture of inorganic particles and a binder polymer, wherein the inorganic particles in the active layer are interconnected among themselves and are fixed by the binder polymer, and interstitial volumes among the inorganic particles form a pore structure. A method for manufacturing the same separator and an electrochemical device including the same separator are also disclosed. An electrochemical device comprising the organic / inorganic composite porous separator shows improved thermal and electrochemical safety and quality, simultaneously.

Disclosed is an organic / inorganic composite porous film comprising: (a) inorganic particles; and (b) a binder polymer coating layer formed partially or totally on surfaces of the inorganic particles, wherein the inorganic particles are interconnected among themselves and are fixed by the binder polymer, and interstitial volumes among the inorganic particles form a micropore structure. A method for manufacturing the same film and an electrochemical device including the same film are also disclosed. An electrochemical device comprising the organic / inorganic composite porous film shows improved safety and quality.

A lithium battery with improved safety that utilizes one or more additives in the battery electrolyte solution wherein a lithium salt is dissolved in an organic solvent, which may contain propylene, carbonate. For example, a blend of 2 wt % triphenyl phosphate (TPP), 1 wt % diphenyl monobutyl phosphate (DMP) and 2 wt % vinyl ethylene carbonate additives has been found to significantly enhance the safety and performance of Li-ion batteries using a LiPF6 salt in EC / DEC electrolyte solvent. The invention relates to both the use of individual additives and to blends of additives such as that shown in the above example at concentrations of 1 to 4-wt % in the lithium battery electrolyte. This invention relates to additives that suppress gas evolution in the cell, passivate graphite electrode and protect it from exfoliating in the presence of propylene carbonate solvents in the electrolyte, and retard flames in the lithium batteries.

A number of materials with the composition Li1+xNiαMnβCoγM′δO2−zFz (M′=Mg,Zn,Al,Ga,B,Zr,Ti) for use with rechargeable batteries, wherein x is between about 0 and 0.3, α is between about 0.2 and 0.6, β is between about 0.2 and 0.6, γ is between about 0 and 0.3, δ is between about 0 and 0.15, and z is between about 0 and 0.2. Adding the above metal and fluorine dopants affects capacity, impedance, and stability of the layered oxide structure during electrochemical cycling. Another aspect of the invention includes materials with the composition Li1+xNiαCoβMnγM′δOyFz (M′=Mg,Zn,Al,Ga,B,Zr,Ti), where the x is between 0 and 0.2, the α between 0 and 1, the β between 0 and 1, the γ between 0 and 2, the δ between about 0 and about 0.2, the y is between 2 and 4, and the z is between 0 and 0.5.

The invention discloses a composite diaphragm which comprises a supporting layer and an organic / inorganic particle blended coating layer, laminated; the coating layer comprises a polymer particle and an inorganic particle, uniformly mixed in an adhesive; micropore structures are arranged on the surface and at the inner part of the coating layer; the porosity is 20%-80%; the aperture average is 0.01 to 10 micrometers; the polymer particle comprises one or more of polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyimide, polyacrylonitrile and aramid fiber resin; the particle size of the polymer particle is 0.01-10 micrometers; the inorganic particle comprises any one or more of SiO2, Al2O3, CaO, TiO2, MgO, ZnO, SnO2 and ZrO2; the particle size of the inorganic particle is 0.01-10 micrometers; the mass ratio of the polymer particle to the inorganic particle is (1:10) to (10:1). The invention further discloses a method for preparing the composite diaphragm. The composite diaphragm and the method have good thermal safety and strong in electrolyte absorption stiffness value, and meanwhile, and can achieve the advantages of low cost and low pollution.

A positive active material for a rechargeable lithium battery is provided. The positive active material includes a core having a lithiated compound and at least two surface-treatment layers on the core, and each of the two surface-treatment layers includes at least one coating element. Alternatively, the positive active material includes at least one surface-treatment layer on the core, wherein the surface treatment at least comprises at least two coating element-included oxides.

The invention discloses an inorganic / organic composite porous membrane, which comprises a porous base material and an active layer attached to the porous base material, wherein the active layer contains a mixture of inorganic granules and a bonding agent. In the inorganic / organic composite porous membrane, the defect of poor heat safety of the conventional polyolefin-base diaphragm is overcome by using the inorganic / organic composite porous membrane formed by the porous base material, the inorganic granules and the bonding agent; the inorganic / organic composite porous membrane has the high antioxidation, can prevent the diaphragm from being oxidized in a lithium battery of a high-voltage anode material system, has the absorption and infiltration capacity of electrolyte which is better than that of conventional polyolefin-base diaphragm, and can improve solve the problem of the absorption and infiltration of the electrolyte in the large-size lithium battery and the lithium precipitation of the battery effectively. Therefore, the inorganic / organic composite porous membrane can improve the performance and safety of an electrochemical device serving as the inorganic / organic composite porous membrane as the diaphragm. In addition, the invention also discloses a preparation method for the inorganic / organic composite porous membrane and the electrochemical device using the membrane.

Disclosed herein are double-layer cathode active materials comprising a nickel-based cathode active material as an inner layer material and a transition metal mixture-based cathode active material as an outer layer material facing an electrolyte. Since the nickel-based cathode active material as an inner layer material has high-capacity characteristics and the transition metal mixture-based cathode active material as an outer layer material facing an electrolyte has superior thermal safety, the double-layer cathode active materials have high capacity, high charge density, improved cycle characteristics and superior thermal safety.

The present invention refers to a separator for an electrochemical device and an electrochemical device having the same. More specifically, the separator of the present invention comprises a porous substrate; a first porous coating layer formed on one surface of the porous substrate and comprising a mixture of inorganic particles and a first binder polymer; and a second porous coating layer formed on the other surface of the porous substrate and comprising a product obtained by drying a mixture of a solvent, a non-solvent and a second binder polymer.Such separator of the present invention can have good thermal safety due to a porous organic-inorganic coating layer formed on one surface thereof, and superior adhesiveness due to a porous coating layer made of a binder thin film formed by applying and drying a mixture of a binder polymer and a non-solvent on the other surface thereof. Also, the separator can have a decreased thickness to reduce the resistance of electrochemical device and improve the capacity thereof.

The invention relates to a polyolefin compound film, comprising a polyolefin layer and a refractory coating which are adhered together. The refractory coating comprises a refractory material and vents distributed on the material, wherein, an average diameter of the vents on the material is not greater than 1 micron. The polyolefin compound film provided by the invention is provided with high strength and independent film layer structure can be preserved even after the polyolefin layer is melted and collapses. If the polyolefin compound film provided by the invention is used as a diaphragm of a lithium ion battery, the refractory layer of the compound film can avoid a contact between an anode and a cathode of the battery and prevent short circuit of the battery even though the polyolefin layer of the diaphragm is melted and collapses so as to really enhance the thermal security capability of the lithium ion battery. The polyolefin compound film provided by the invention has the advantages that the refractory capability is excellent; heat-shrinking is little and the strength is high. By being adopted as the diaphragm of a lithium ion secondary battery, the invention can effectively enhance the thermal security capability and circulation capability of the battery.

The invention provides a lithium ion battery anode material coated with piezoelectric material on the surface and a preparation method thereof. The surface of the battery anode material is coated witha layer of piezoelectric material with piezoelectric effect; the piezoelectric material comprises any one or more of barium titanate, lithium niobate, sodium niobate, lithium tantalite, sodium-potassium metaniobate and barium-strontium metaniobate with piezoelectric effect. The piezoelectric characteristic of the piezoelectric material is utilized to realize a coating modification function for the anode active materials so as to ensure that the volume phase structures of the anode active materials are not influenced and damaged, the growth of solid-electrolyte interface membranes is suppressed, and the diffusion speeds of active material-coating layer interface lithium ions are improved, thereby effectively improving the structure stability and electrochemical cycle performance of the lithium ion battery anode material, improving the pyrolysis temperature of the anode material and then enhancing the safety performance of the lithium ion batteries in the using process.

The invention discloses a porous inorganic membrane used as a separator of a lithium ion battery and a preparation method thereof. The composition of the porous inorganic membrane of the present invention is alumina, silica or magnesia. The preparation method of the porous inorganic membrane of the present invention includes the following steps: mixing and grinding the insulating inorganic material and the pore-forming agent, pressing the membrane under a pressure of 2-20 MPa, and repeating the calcining of the pressed membrane twice at 300-1600°C, and then successively A porous inorganic membrane with stable structure and high porosity was obtained after ultrasonic cleaning in deionized water and ethanol. The porous inorganic membrane of the present invention is used as a lithium-ion battery diaphragm material, and has significant thermal stability and thermal safety advantages, and the battery using the porous inorganic membrane of the present invention shows better cycle performance, rate performance and high and low temperature performance. The porous inorganic membrane prepared by the invention can improve the thermal safety and electrochemical performance of the lithium ion battery, and has stable performance and low cost.

The invention discloses a polyolefin lithium battery diaphragm. A porous polyolefin diaphragm is taken as a substrate, a modified PET fiber coating is electrostatically spun on one side of the polyolefin diaphragm or each of the two sides of the polyolefin diaphragm respectively, and modified PET fibers are fibers formed by compounding inorganic oxide nano-particles and PET. The polyolefin lithiumbattery diaphragm is provided for solving the problem that the high temperature integrity of the existing polypropylene or polyethylene porous diaphragm is lower, the problems that a pore structure or a composite structure of the existing electrostatically spun diaphragm is not uniform, and the like; the polyolefin lithium battery diaphragm can bear the temperature of 250-260 DEG C; the problem that pores are closed as a material is melted under the maximum condition of abuse of batteries is effectively avoided; the polyolefin lithium battery diaphragm has good high temperature integrity, sothat the thermal safety of the batteries can be greatly improved.

The invention relates to the technical field of lithium batteries, in particular to a lithium battery diaphragm with high thermostability and a preparation method thereof. The lithium battery diaphragm is composed of a polyimide nucleopore membrane, a ceramic layer and an electrostatic spinning nanofiber layer, polyimide with high heat resistance performance and high insulating performance is taken as a base membrane, and the base membrane is successively coated with the ceramic layer and the electrostatic spinning nanofiber layer; porous aluminium oxide in the ceramic layer has better heat conduction performance, heat on the diaphragm can be timely conducted, and it is avoided that the short circuit phenomenon occurs due to excess local thermal contraction; the electrostatic spinning nanofiber layer not only can improve the evenness of the diameter of holes in the surface of the diaphragm and improve the thermostability of the lithium battery diaphragm, but also can be closely combined with the ceramic layer to avoid falling of the porous aluminium oxide in the ceramic layer; the lithium battery diaphragm prepared by adopting the method has the advantages that the thermostabilityis good, and the heat conduction effect is excellent.

The invention discloses a scrap preheater of an electric-arc furnace step disturbance culvert. The scrap preheater comprises a heat-exchanging culvert, the low side of the heat-exchanging culvert is connected with a furnace, the high side of the heat-exchanging culvert is respectively connected with a smoke-collecting and dust-removing pipe and a feed sealing device, the heat-exchanging culvert comprises a material- conveying groove and a smoke guide cover, the material-conveying groove is used for conveying steel scrap materials to the electric-arc furnace, the smoke guide cover is covered on the material- conveying groove and is used for guiding smoke, the heat-exchanging culvert is provided with at least one cross-section abrupt change structure in the height-extending direction, and the cross-section abrupt change structure is used for disturbing the steel scrap material flow state and the smoke flow state. The invention further discloses a preheating method of the electric-arc furnace step disturbance culvert, and the steel scrap materials can be added to the material-conveying groove by the feed sealing device; the steel scrap material flow state is disturbed under the combined action of the cross-section abrupt change structure on the heat-exchanging culvert and horizontal vibration, so that the steel scrap materials have air permeability in a certain area; and the smoke flow state can be disturbed in the smoke guide cover, so that the smoke and the steel scrap materials can be subjected to heat exchanging fully.

The invention provides a lithium ion battery composite diaphragm and a preparation method thereof, relating to the technical field of batteries. The lithium ion battery composite diaphragm comprises abase film and an aramid fiber coating and the water-based PVDF composite coating which coat one side of the base film; the water-based PVDF composite coating is prepared from, by weight, 1-10% of a base material and the balance of deionized water, and the base material is prepared from PVDF, a dispersing agent, a thickening agent, an adhesive, nano aramid fiber powder, DMAC or DMF, a cosolvent, an emulsifying agent and a pore forming agent. Compared with the prior art, the aramid fiber coating diaphragm disclosed by the invention has better heat resistance, stability, electrical insulating property and flame retardant property on the whole; the PVDF coating is obtained by coating and drying water-based PVDF slurry, the traditional process that acetone and other oily substances serve as solvents of an existing PVDF-coated lithium ion battery diaphragm is abandoned, and the safety performance, the rate capability and the cycle performance of a lithium ion battery prepared from the diaphragm are obviously improved.

The invention discloses a composite diaphragm with excellent high temperature performance and pore closing performance. The composite diaphragm is prepared by compounding a polyimide electrostatic spinning layer, a PE (Poly Ethylene) microporous membrane layer and a PP (Polypropylene) microporous membrane layer in sequence. The invention further discloses a preparation method of the composite diaphragm. The composite diaphragm has the advantages of high safety as well as excellent high temperature performance and pore closing performance.

The invention relates to a modification method for fireworks and crackers by coating potassium chlorate, belonging to the field of fireworks and crackers. The invention comprises the steps as follows: firstly, coupling agent is employed to form a first coating film on the surface of potassium chlorate particles; secondly, a layer of high polymer material is coated to form a second coating film. The method greatly reduces the mechanical sensitivities of fireworks and crackers agents such as friction, collision and the like under the condition that the setting off effect of the fireworks and crackers is not influenced, coincides with national standards and improves the thermal safety.

A separator for a rechargeable lithium battery includes: a substrate; and a coating layer on at least one side of the substrate, the coating layer including an acrylic-based copolymer obtained from polymerization of a (meth)acrylate salt and (meth)acrylonitrile, and a polyvinyl alcohol-based compound. A rechargeable lithium battery including the separator is also provided.

The invention relates to a thermal safety battery, which comprises electrode group and electrolyte, both sealed in the battery frame. Wherein, the electrode group comprises anode plate, cathode plate and the separating layer, while their widths meet Wto>=3mm, Wn>=Wp, and Wto=Ws-Wn-Wbo, Wn is the width of cathode plate, Wp is the width of anode plate, Ws is the width of separating layer, Wto is the exposed width at one end of separating layer, and Wbo is the exposed width at another end of separating layer.

The invention provides a lithium ion battery pole piece, a production method and a battery cell. The pole piece comprises a positive pole piece and a negative pole piece which are arranged in an overlapping manner; the negative pole piece comprises a negative pole piece body as well as a first ceramic coating and a functional coating which are sequentially coated in a direction from a body to theouter part; the surface of the functional coating or the surface of the positive pole piece is coated with a second ceramic coating; the functional coating is prepared by mixing metal lithium complexpowder, an adhesive, a flatting agent and water. The invention has the advantages that thermal safety of the battery can be improved and the growth of lithium dendrites is inhibited; the functional coating only participates in an electrochemical reaction when the lithium dendrites are grown and does not participate in the electrochemical reaction when the battery cell normally discharges, so thatno special electrolyte is needed and the cost is effectively reduced.

The invention provides a battery thermal safety performance and fire extinguishing system comprehensive detection platform which comprises a fire extinguishing system, a thermal safety performance evaluation system and a fire early warning system. The fire extinguishing system comprises a fire extinguishing device and a fire extinguishing effectiveness evaluation mechanism; the fire extinguishingdevice comprises various fire extinguishing mechanisms fixed in a simulated battery box in a closed state; the fire extinguishing effectiveness evaluation mechanism comprises temperature sensors fixedaround a tested battery; the temperature sensors are communicated with a user side; the fire early warning system comprises detectors fixed at different heights in the simulated battery box; a plurality of detectors are communicated with the user side by a data module; and the thermal safety performance evaluation system acquires flue gas to carry out analysis. The platform provided by the invention integrates thermal safety performance evaluation, fire extinguishing system test and the fire early warning system, and is simple in structure, easy to assemble and repair, visual in testing process and accurate in data. The simulated battery box also can provide two environment demands for opening and closing when having a high-intensity protection function.

A metal capacitor in which an electric conductivity is significantly improved by applying a metal material for an electrolyte and a manufacturing method thereof is provided. The capacitor includes a metal member comprising a groove forming portion where a plurality of grooves is formed, an electrode withdrawing portion formed on the groove forming portion, and a sealing portion; a metal oxide layer being formed on the metal member; an insulating layer being formed on the metal member to expose the electrode withdrawing portion of the metal member; a plurality of main electrode layers, each main electrode layer being formed on the metal oxide layer that is formed on the groove forming portion of the metal member; and a conductive connecting layer being formed on the plurality of main electrode layers and the insulating layer to face the electrode withdrawing portion of the metal member and connect the plurality of main electrode layers, wherein a lead terminal is connected to the electrode withdrawing portion of the metal member and each of the main electrode layers.

The invention relates to a diaphragm for a lithium ion battery and a preparation method thereof. The diaphragm has a thickness of 5-10[mu]m and a thermal shrinkage rate of less than 1.2% at 150 degrees centigrade, and comprises a first ceramic layer, gel polymer layers on both sides of the first ceramic layer, and third ceramic layers on the outer surfaces of the gel polymer layers, wherein the first ceramic layer comprises 60-80% by weight of ceramic oxide and 20-40% by weight of a binder, wherein the ceramic oxide has a particle diameter of 10-30 nm; each gel polymer layers is an aqueous solution of polymer particles having a particle diameter of 30 to 50 nm; and each third ceramic layer comprises 80-90% by weight of ceramic oxide and 10-20% by weight of the binder, wherein the ceramic oxide has a particle diameter of 30-80 nm. The diaphragm has a low thickness, good high temperature resistance, a low thermal shrinkage rate and good stability.

The invention provides a hybrid electric vehicle thermal management system one-dimensional simulation modeling method. Comprising a power driving system model, an electrical system model, an engine cooling system model, a power battery thermal management system model, a motor electric control cooling system model, an air conditioning system model, a passenger compartment model, a vehicle energy management control model, a thermal management system control model and the like. According to the coupling relation of energy management and heat management of the whole vehicle, the simulation models of all the systems and the simulation models of the control modules are integrated by combining the transmission paths of energy flow and heat flow of the whole vehicle, control logic and the like, and a one-dimensional joint simulation model of the whole vehicle heat management system of the hybrid electric vehicle is constructed; a simulation platform is provided for integrated design, system component model selection matching, comprehensive performance analysis, control strategy optimization, energy consumption and driving range analysis and prediction and the like of a hybrid electric vehicle thermal management system.

The invention provides a percutaneous wireless charging device with a multi-closed-loop temperature control and protection function for implantable medical devices. Thermal safety and high energy transfer efficiency of the percutaneous wireless charging device in different charging stages and at different alignment positions are realized through multi-closed-loop temperature control and highest temperature protection design. By controlling the temperature with high steady-state accuracy, stable charging in short charging time is realized, and thermal safety in the charging process is ensured.