32results about How to "Avoid internal short circuit" patented technology

The invention discloses a polymer lithium ion battery and a preparation method of a diaphragm of the polymer lithium ion battery. The preparation method comprises the following steps: dissolving P(VDF-HFP) into an organic solvent, and adding inorganic ultra-fine powder into the mixture by adopting an in-situ hydrolysis method so as to prepare a mixed solution of P(VDF-HFP)-TiO2; coating the mixed solution on a polyolefin diaphragm so that the solvent is volatilized and a composite porous membrane is formed on the diaphragm; then assembling positive and negative pole pieces with the diaphragm; injecting liquid electrolyte into an electric core after assembling; and heating and baking the electric core so that the composite porous membrane and the electrolyte form a gel so as to prepare a gel polymer battery. The method has a simple technological process for preparing the polymer battery, low cost and wide application range of a production process; and the manufactured composite porous membrane has the advantages of high liquid absorption rate, high porosity and stable structure, and the battery has good cycling performance and electric conductivity.

The invention relates to the technical field of lithium-ion batteries, and particularly discloses a positive pole piece of the lithium-ion battery and the lithium-ion battery. The positive pole piece of the lithium-ion battery comprises a current collector foil, a membrane, tabs and an insulating protective layer, wherein the membrane coats the current collector foil; the insulating protective layer is pasted on the current collector foil and covers the edge of the membrane; the tabs are arranged on the current collector foil; and a cut edge formed by cutting the tabs on the current collector foil is located in a coverage area of the insulating protective layer. The lithium-ion battery comprises the positive pole piece of the lithium-ion battery disclosed by the invention. An inner short circuit formed by burrs generated when the pole piece is molded and a negative electrode since the burrs puncture an isolating membrane can be effectively prevented; and the safety performance of the lithium-ion battery is improved.

The invention discloses a method for preparing a gel polymer lithium ion battery, which comprises the following steps: dissolving P(VDF-HFP) into an organic solvent, and adding inorganic ultra-fine powder into the mixture by adopting an in-situ hydrolysis method so as to prepare a mixed solution of P(VDF-HFP)-TiO2; coating the mixed solution on positive and negative pole pieces of the battery so that the solvent is volatilized, and composite porous membranes are formed on the positive and negative pole pieces; assembling the pole pieces containing the composite porous membranes with a diaphragm; injecting liquid electrolyte into an electric core after assembling; and heating and baking the electric core so that the composite porous membranes and the electrolyte form a gel so as to preparea gel polymer battery. The method has a simple technological process for preparing the polymer battery, low cost and wide application range of a production process; and the manufactured composite porous membranes have the advantages of high liquid absorption rate, high porosity and stable structure, and the battery has good cycling performance and electric conductivity.

This invention relates to a Li secondary battery of non-aqueous liquid electrolyte including a negative pole and a positive pole capable of inlaying and disinlaying the Li ionic battery, membranes and non-aqueous liquid electrolyte housed in a outer shell of the battery, among which, a support is put in the cove composed of positive, negative plates and membranes, side pressure plates are placed at the outside or of the core, pressed by wedge blocks to make the core bend, laterally fixed in the shell by the top and bottom insulators, which has excellent multiplying factor discharge performance and safety performance.

The invention relates to a composite diaphragm for an alkali metal battery and a preparation method of the composite diaphragm. The composite diaphragm comprises an organic diaphragm matrix layer coated with a ceramic coating and an amorphous alkali metal ion conductor inorganic solid layer, and the preparation method is a vacuum physical deposition method and comprises the following steps of passing an organic diaphragm substrate through a vacuum deposition cavity in a roll-to-roll mode, wherein the vacuum degree of a vacuum box body is 0.5-5 Pa, the reaction gas is nitrogen, the deposition power supply power is 30-180 W, the deposition time is 5-30 min; and depositing to prepare the composite diaphragm. The deposited inorganic solid layer is compact and non-porous, so that the diaphragmhas very strong mechanical property and high-temperature resistance, and the internal short circuit caused by the battery impurities and the metal dendrites and the thermal deformation of the batterydiaphragm can be effectively prevented. Meanwhile, the inorganic solid layer has the alkali metal cation high-speed conduction performance, stability in air and a hetero-ion blocking function, so thatthe safety performance and the cycle life of the battery can be remarkably improved.

The invention provides a negative plate and a lithium ion battery comprising the same. The negative plate is formed by coating a conductive coating between a negative current collector and a first negative active material layer, so that the contact resistance between the first negative electrode active material layer and the negative electrode current collector can be reduced, the acting force between the first negative electrode active material layer and the negative electrode current collector is improved, peeling of the first negative electrode active material layer is avoided, the buffer coating is coated between the first negative electrode active material layer and the second negative electrode active material layer, the contact resistance between the first negative electrode activematerial layer and the second negative electrode active material layer can be reduced, the acting force between the first negative electrode active material layer and the second negative electrode active material layer is improved, and the transmission rate of ions and electrons is increased; and the surface of the second negative electrode active material layer is coated with the safety coating,so that the volume expansion of the second negative electrode active material layer is further buffered, the lithium dendrites can be prevented from directly piercing the diaphragm to cause internal short circuit, and the safety risk is reduced.

The invention discloses a preparation method of a solid-state battery, which comprises the following steps: mixing a positive active material, a solid electrolyte, a binder, a conductive agent and a first solvent, and intermittently coating a positive current collector with the mixture to obtain a positive electrode; adding the solid electrolyte into a second solvent to obtain a solid electrolyte filling liquid; mixing a binder, a solid electrolyte and a third solvent to obtain solid electrolyte slurry; mixing a negative electrode active material, a solid electrolyte, a binder, a conductive agent and a fourth solvent to obtain negative electrode slurry; and coating or curtain coating on the positive electrode according to a lamination sequence of the solid electrolyte filling liquid, the solid electrolyte slurry and the negative electrode slurry, and drying to obtain the integrated electrode. The invention also discloses an integrated electrode, an integrated solid-state battery module and a solid-state battery. The electrode plate is filled with the solid electrolyte, and the integrated module is prepared, so that the interface impedance is reduced, the ion transmission capability of the electrode is improved, the procedures of electrode plate preparation and cell assembly are simplified, and the cost is reduced.

The invention relates to a lithium battery pole piece slitting burr detector. The detector consists of a baseplate, a side bracket, a hand wheel, a screw rod, a screw nut, a transition frame, a guide pillar, a sliding bearing, an up-down adjustment bracket, a fixed ring, a microscope and a clamp plate group. On the baseplate, the screw rod passes through the side bracket through a bearing seat, one end of the screw rod goes through the side bracket and is connected to the hand wheel, the screw nut is in threaded engagement with the screw rod, and is fixedly connected in the transition frame, the guide pillar is parallel to the screw rod and passes through the side bracket on both sides of the baseplate, the guide pillar passes through the transition frame through the sliding bearing, the up-down adjustment bracket perpendicular to the baseplate is fixedly connected to the transition frame, the fixed ring is connected to the up-down adjustment bracket through a clamp seat, the microscope is fixedly sleeved on the fixed ring, the baseplate is provided with the clamp plate group that is parallel to the screw rod and is used for clamping a pole piece, and corresponding to a position above the clamp plate group, the microscope is in a state of mobile measurement of pole piece cut burr along the clamp plate group direction.

The invention discloses a polymer electrolyte and a preparation method and application thereof. The polymer electrolyte comprises a polymer matrix, the polymer matrix is a polymer formed by self-polymerization of a polymeric monomer composed of three building blocks of acryloyl, carbamate and phosphate, or a polymer formed by copolymerizing a polymeric monomer and other monomers, wherein the polymeric monomer is composed of three building blocks, namely acryloyl, carbamate and phosphate. The polymer electrolyte can be used in a battery, the polymer matrix can be subjected to a self-crosslinking reaction at a high temperature of 130-190 DEG C to generate a compact thermosetting polymer which can cut off ion transmission and prevent thermal runaway of the battery; the self-crosslinking reaction is an endothermic reaction, so that the temperature of the battery can be quickly reduced, and the thermal runaway of the battery can be prevented; the polymer electrolyte can capture free radicals and has intrinsic flame retardance; and the characteristics of the polymer matrix are synergistic, so that the thermal runaway of the battery can be effectively prevented.

The invention provides a negative plate with a sandwich structure and a lithium ion battery comprising the negative plate. When a conventional lithium ion battery is subjected to a needling test, an internal short circuit occurs, a large amount of heat is generated in a short time due to relatively large current density of the internal short circuit, thermal shrinkage of a diaphragm is caused, andfinally thermal runaway of the battery is caused. A lithium titanate layer is contained in the negative plate, lithium can be rapidly removed at the moment of internal short circuit to form an air-state insulator, the resistance of the negative plate is sharply increased in the process, the short-circuit current can be reduced, and then the needling safety of the lithium ion battery can be improved. A silicon material layer is contained in the negative plate, lithium dendrites can be consumed through reaction when the silicon material layer makes contact with the lithium dendrites, the situation that the negative plate seriously separates out lithium to form a large number of lithium dendrites in the overcharge process of the battery cell is avoided, and internal short circuit caused by the fact that the lithium dendrites pierce a diaphragm is further avoided.

The invention relates to a negative pole piece as well as a preparation method and application thereof. The negative pole piece comprises a current collector, and an active material layer and an insulating safety coating which are sequentially arranged on the surface of the current collector; and the insulating safety coating comprises coarsened ceramic particles. The insulating safety coating comprises the coarsened ceramic particles, the coarsened ceramic particles can be more tightly adhered to the surface of the negative electrode active substance, uneven dense accumulation of the ceramicparticles is prevented, and then the problem of uneven coating is solved; and by coating the surface of the negative pole piece with the insulating safety coating, negative lithium precipitation occurs between the safety coating and the negative interface, so that lithium dendrites are prevented from being in direct contact with the diaphragm, and internal short circuit of the lithium ion batterydue to the fact that the lithium dendrites pierce the diaphragm is prevented.

The invention discloses a positive pole current collector, a positive pole piece and an electrochemical device. The positive pole current collector comprises a support layer and a conductive layer arranged on the support layer, the conductive layer is made of aluminum or aluminum alloy, and the thickness D1 of the conductive layer is greater than or equal to 300nm and less than or equal to 2mu m;the elongation at break B of the supporting layer is greater than or equal to 12% and greater than or equal to 10000%; the volume resistivity of the supporting layer is greater than or equal to 1.0 *10 <5> ohm.m; when the tensile strain of the positive electrode current collector is 2%, the square resistance growth rate T1 of the conductive layer is less than or equal to 10%. The positive electrode current collector provided by the invention can give consideration to relatively high safety performance and electrical performance at the same time, so that the positive electrode piece and the electrochemical device adopting the positive electrode current collector can give consideration to relatively high safety performance and electrochemical performance at the same time.

The invention discloses a lithium ion power battery with heat runaway control function, comprising a hollow battery case (3), wherein a battery core pack (4) is arranged in the battery case (3); A left end and a right end of that top of the battery core pack (4) are respectively provided with a positive terminal (1) and a negative terminal (6); The outer surface of the battery core pack (4) is provided with a thermal runaway blocking device (2). The thermal runaway blocking device (2) is respectively connected with a positive terminal (1) and a negative terminal (6); Said thermal runaway blocking means (2) being in contact with the battery case (3) for transferring heat on the battery case (3) and causing a short circuit of the battery to occur outside the battery pack (4) when the temperature thereon rises to a preset temperature value. The invention is safe and reliable, can effectively avoid internal short circuit of the lithium ion power battery, prevents the safety accident of thelithium ion power battery due to the internal short circuit, and guarantees the safety performance of the battery.

The invention discloses a method of preparing a gel polymer lithium ion battery, comprising the following steps: solving P(VDF-HFP) in organic solvent, and then adding P(VDF-HFP) nonsolvent to obtain mixed P(VDF-HFP) solution; spreading the mixed P(VDF-HFP) solution on the diaphragm or the positive electrode plate and the negative electrode plate of the lithium ion battery to volatilize the solvent of the mixed P(VDF-HFP) solution and form a composite porous film on the diaphragm or the positive electrode plate and the negative electrode plate of the lithium ion battery; assembling the positive electrode plate and the negative electrode plate with the diaphragm of the lithium ion battery, and injecting liquid electrolyte in to as assembled electrical core; and heating and baking the electrical core to make the composite porous film and the liquid electrolyte form gel to obtain the gel polymer lithium ion battery. The method of preparing the gel polymer lithium ion battery has simple process, low cost and wide application range and ensures that the produced composite porous film has high liquid absorption rate and stable structure and the gel polymer lithium ion battery has good cycling performance and conducting performance.

The invention relates to the technical field of the design of capacitor pole piece structures, and especially a capacitor pole piece with the protection layer. The capacitor pole piece comprises a metal current collector, and the external surface of the metal current collector is wrapped by an active substance layer which is wrapped by a nylon cloth layer. The surface of the nylon cloth layer is wrapped by a scraping-resistant macromolecular coating layer which is wrapped by an insulating rubber layer. Compared with the prior art, the capacitor pole piece is simpler in structure, and the active substance layer of the metal current collector of the capacitor pole piece is sequentially wrapped by the nylon cloth layer, the scraping-resistant macromolecular coating layer and the insulating rubber layer, which can achieve the effective protection of the pole piece, avoids the internal short circuit phenomenon, caused by the collision and torsion, of a capacitor, and prolong the service life of the capacitor. The capacitor pole piece is convenient and practical, and is suitable for popularization and application.