74results about How to "Guaranteed Energy Density" patented technology

The invention relates to the technical field of lithium-ion battery anode materials and in particular relates to a preparation method of a nickel cobalt lithium manganate composite anode material. By utilizing the preparation method, recycling of lithium manganate fine powder is realized, the safety performance of the material can be improved by adding the lithium manganate into ternary material, frit reaction among particles is strengthened by adding a binding agent so that the lithium manganate fine powder is tightly coated on the surface of the ternary particles so as to improve product stacking density, and side reaction between the material and electrolyte can be obstructed by the binding agent remained on the surface of the nickel cobalt lithium manganate composite anode material after high-temperature fusion so as to improve the cycle performance of the material and further improve the safety performance of the material. Compared with the prior art, by utilizing the composite anode material, energy density of nickel cobalt lithium manganate is kept and the safety performance is improved. The composite anode material is one of optimal anode materials applied to power batteries of electromobiles, electric power tools and the like.

The invention relates to a processing method for carrying out focused microwave cutting on a brittle material, which is characterized in that microwave energy high-density focusing is realized by using a tapered waveguide, and microwave beams are emitted to the surface of a workpiece from the front end of the tapered waveguide in a high energy density beam mode so as to heat the workpiece, thereby realizing the cutting processing according to the principle of a hot cracking method. The waveguide comprises a cone-shaped mode converter by which the microwave focusing can be realized; and the processing device is provided with a three-dimensional operating platform by which the processing requirements of any curve can be realized. The invention also relates to a processing device for carrying out microwave cutting on a brittle material by using the processing method.

The invention discloses a method for improving electrolytic solution resistance of a lithium battery negative electrode binder through irradiation, and belongs to the technical field of lithium batteries. The method comprises the following steps: preparing a lithium battery containing a negative electrode taking sodium carboxymethyl cellulose (CMC-Na) and styrene-butadiene rubber emulsion (SBR) asbinders; and placing the whole battery on an under-beam device of an electron beam irradiation accelerator, and irradiating the whole lithium ion battery, wherein the irradiation dose is 10 to 100 kGy, the irradiation dose rate is 2-10 kGy/s, and in the negative electrode, CMC-Na and SBR can generate intramolecular and intermolecular chemical cross-linking so as to improve the electrolytic solution resistance of the binders CMC-Na and SBR in the negative electrode sheet, reduce the swelling of the binders CMC-Na and SBR in the electrolytic solution, reduce the thickness expansion rate of thenegative electrode sheet in the battery circulation process, improve the capacity retention rate of the battery and prolong the service life of the battery. The process is simple and easy to implement, low in cost and suitable for consumer electronic lithium batteries and power type lithium batteries.

The invention discloses an NCMA quaternary gradient material and a preparation method thereof. The material sequentially comprises an inner core structure, a shell structure and a coating layer from inside to outside, wherein the coating layer contains an element Mg, a chemical general formula of the material except the coating layer is LiNixCoyMnzAlwO2, and values of x, y, z and w simultaneouslymeet the following conditions, 0.8 </= x </= 1, 0 </= y </= 0.1, 0 </= z </= 0.2, 0 </= w </= 0.1, and x + y + z + w = 1, a general chemical formula of the core structure is LiNiaCoyMnbAlwO2, a general chemical formula of the shell structure is LiNicCoyMndAlwO2, a is larger than or equal to 0.8 and smaller than or equal to 1, b is larger than or equal to 0 and smaller than or equal to 0.2, a is larger than x, b is smaller than z, and a + y + b + w = 1, c is larger than 0 and smaller than or equal to 0.6, d is larger than or equal to 0.3 and smaller than or equal to 0.9, c is smaller than x, dis larger than z, and c + y + d + w = 1. The material is advantaged in that cycle performance of the high-nickel material can be effectively improved while a high-nickel structure is guaranteed, the method is simple in manufacturing process and high in operability, industrial production of the high-nickel material is facilitated, and problems that in the prior art, cycle performance of the high-nickel material is poor, and the manufacturing environment requirement is high are solved.

The invention relates to the technical field of a lithium battery, particularly a graphite negative electrode structure combination and a preparation method thereof. The graphite negative electrode structure combination comprises a negative electrode structure and a surface modification layer formed on the negative electrode structure; the negative electrode structure comprises a negative electrode current collector and a graphite negative electrode layer formed on the negative electrode current collector; the negative electrode current collector, the graphite negative electrode layer and thesurface modification layer are arranged in an overlaid manner; the graphite negative electrode layer comprises a graphite active material; and the surface modification layer comprises a lithium compound with the ionic conduction characteristic. By taking the surface modification layer as a stable artificial SEI membrane, lithium ion damage in the charging cycle process can be well reduced, the initial charging and discharging coulombic effect is improved, and the specific capacity density of the graphite negative electrode layer is improved; and meanwhile, the surface modification layer can well block macromolecule groups from being nested into the graphite negative electrode layer along with lithium ions, so that stripping of graphite can be avoided, the structural stability of the negative electrode structure can be maintained, and stable conductive performance can be achieved.

The invention discloses a lithium battery core and a manufacturing method. The lithium battery core comprises at least one positive electrode sheet, at least one negative electrode sheet and at least one diaphragm, wherein the positive electrode sheet comprises a positive current collector and a positive electrode active material, the positive current collector comprises a plurality of first small sheets which are parallel at intervals, the adjacent first small sheets are connected by bent blank areas, the positive electrode active material is coated on the side surface of the first small sheet, the negative electrode sheet comprises a negative current collector and a negative electrode active material, the negative current collector comprises a plurality of second small sheets which are parallel at intervals, the adjacent second small sheets are connected by bent blank areas, the diaphragm is bent in an S shape, and the first small sheets and the second small sheets are sequentially and alternately connected to the space formed after the diaphragms are bent and between the adjacent diaphragms, and are connected with the diaphragms. The manufacturing method comprises the steps of inserting, folding and combining. According to the invention, the electrode sheets are fixed, the short-circuit risk of the battery core is reduced, the production efficiency is improved, the lamination qualification rate can be effectively improved, and the production process is effectively simplified.

In order to solve the technical problems that a traditional heat dissipation scheme of a battery cabin section of an underwater vehicle is low in heat dissipation efficiency and not obvious in effect, and the temperature of the battery pack cannot be effectively reduced in a short time, the invention provides the high-thermal-conductivity lithium battery pack for the underwater vehicle. According to the invention, the gaps inevitably formed when the cylindrical lithium batteries are arranged are effectively utilized, the gaps are filled with the high-heat-conduction and insulating heat-conduction gap filling material, and heat in the centers of the batteries can be rapidly conducted to the inner wall of the shell of the battery cabin section through the heat-conduction material, so the heat is further conducted to low-temperature seawater outside the battery cabin section, and the purpose of rapid cooling is achieved; the periphery of each cylindrical lithium battery is filled with the heat conduction gap filling material, so that the temperature uniformity can be well ensured; meanwhile, the central gap formed by the cylindrical lithium battery on the innermost ring is reasonably utilized, the central tube is arranged in the central gap, and the central tube is filled with the high-heat-absorption composite material, so heat generated by the battery pack can be quickly and effectively absorbed, and the temperature of the battery pack is reduced.

The invention discloses a hierarchical porous pole piece and a preparation method thereof. Grading coating and pore forming agent addition are utilized to perform grading regulation and control on thepore structure of the pole piece, thereby enhancing the liquid absorption capacity of the pole piece, ensuring the maximization of the active substances, and ensuring the energy density of the battery on the basis of enhancing the electrochemical properties of the pole piece. The pole piece and a lithium piece are assembled into a button cell, it is proved that the material shows excellent electrochemical performance, the electrode polarization can be effectively reduced, and the energy density and the cycling stability of the cell are improved.

The invention discloses a negative pole piece with a coating layer as well as a preparation method and application of the negative pole piece. The negative pole piece comprises a negative current collector, and a negative material layer and the coating layer which are sequentially positioned on the surface of at least one side of the negative current collector, wherein a negative active substancein the negative material layer comprises a silicon oxide molecular sieve, and the coating layer comprises simethicone and lithium salt. According to the invention, the negative electrode material replaces the use of lithium metal by adopting the silicon oxide molecular sieve, the silicon oxide molecular sieve is a porous silicon material, the negative pole piece material is prepared from the material, and the surface of the negative pole piece material is coated with the coating layer made of a special material, so that the internal resistance can be effectively reduced, and the battery performance is improved. Meanwhile, the positive electrode is prepared from a high-nickel ternary nickel-cobalt-manganese material, so that the performance of the solid-state battery can be further improved, and the high-energy-density all-solid-state battery can be obtained.

The invention discloses an array type positive electrode current collector for a liquid metal battery. By arranging a columnar array pointing to the direction of a negative electrode at the bottom ofa positive electrode current collector shell, the distribution uniformity of the positive electrode interface of the liquid metal battery is effectively improved, the internal stress of an interface alloy layer is reduced, more attachment sites are provided for the alloy layer, and the short-circuit risk in the operation process of a large-size battery is effectively eliminated, at the same time,the mass transfer process of the battery charging and discharging process can be effectively ensured, and the safe, stable and efficient battery operation is promoted.