19results about How to "Low areal density" patented technology

According to the thin-layer sound absorption superstructure composite acoustic enclosure and the using method, the acoustic enclosure is composed of the cover plate, the conformal frame, the thin-layer sound absorption superstructures and the porous sound absorption materials, the variety of the thin-layer sound absorption superstructures is not limited to one, and the broadband noise reduction effect can be achieved through the parallel superposition design of the thin-layer sound absorption superstructures and the porous sound absorption materials. Wherein the thin-layer sound absorption superstructure can absorb noise in different frequency ranges of medium and low frequency bands, the porous sound absorption material can absorb noise in medium and high frequency bands, and the working bandwidth of the composite acoustic shield after parallel connection and superposition can cover the low, medium and high wide frequency bands. The thin-layer sound absorption superstructure composite acoustic shield further has the advantages of being high in space utilization rate, high in space adaptability, small in thickness, low in surface density and high in material replaceability. Compared with an existing sound insulation cover, on the premise that the thickness is small and the surface density is low, the working frequency band is wider, the sound insulation effect is better, and the sound insulation cover has wide application prospects in noise control of various mechanical and electrical products.

The invention relates to a self-supporting alloy negative electrode and a preparation method thereof. The negative electrode is a composite material containing metal, an intermetallic compound and a high polymer material. The preparation method comprises the following steps: firstly, preparing a copper foil with a circular through hole structure through a direct current electrodeposition method, then coating a layer of polymer insulating film on one surface of the copper foil, and then depositing a layer of dual-phase alloy negative electrode active material on the other surface of the copper foil through a double-target co-sputtering method. And dropwise adding a colloidal electrolyte on the surface of the active material, curing at a certain temperature, and finally pre-embedding lithium to obtain the final alloy negative electrode. The prepared alloy negative electrode has outstanding electrochemical performance: the gram volume is higher than 1000mAh / g, the lithium intercalation and deintercalation potential is lower than 0.5 V (Vs Li / Li < + >), and the alloy negative electrode has high volume and mass energy density; the cycle life is long, and the material can stably circulate for more than 100 cycles; the growth of lithium dendrites can be inhibited, the risk of short circuit is avoided, and the safety is high. The preparation method of the electrode material is simple, and industrial large-scale production can be realized.

The present invention discloses a titanium alloy and aramid lightweight composite protective plate, comprising alternately distributed titanium alloy plates and aramid plates, wherein the total number of layers of the titanium alloy plates and aramid plates is 3 to 7 layers, and the outermost layer of the protective plate is a titanium alloy plate. In addition, the present invention also provides a method for preparing the titanium alloy and aramid lightweight composite protective plate, wherein the titanium alloy plates and aramid plates are coated with an adhesive and then stacked, and then cured at room temperature and high pressure to obtain a composite protective plate. The present invention adopts a multi-layer composite reinforcement method of titanium alloy and aramid, and by designing the thickness of different materials layer by layer, the advantages of the linear ultra-high strength of the aramid material and the high specific strength of the titanium alloy material are maximized in the ability to resist projectile penetration, and the surface density of the protective plate is greatly reduced.

This application provides an electrode processing apparatus and method, belonging to the field of electrode processing technology. The electrode processing apparatus includes: a winding / unwinding device for conveying the workpiece to be processed from the unwinding side to the winding side; and a scribing device disposed between the unwinding and winding sides, used to form grooves on the uncompacted workpiece. The scribing device scribes lines on the uncompacted workpiece, making the scribing operation of grooves on the electrode coating easier and simpler, and increasing scribing efficiency.

The invention discloses an impact-resistant structure wave-absorbing material and a preparation method thereof, and belongs to the technical field of wave-absorbing materials. The impact-resistant structure wave-absorbing material comprises a rubber sheet and a light structure wave-absorbing layer which are stacked in sequence. And the raw materials of the rubber sheet comprise rubber and hollow glass beads filled in the rubber. By filling the hollow glass beads, the impedance matching property between the material and air is remarkably improved, so that electromagnetic waves enter the wave-absorbing layer to the greatest extent to generate loss, and the wave-absorbing property of the material is effectively improved; the rubber sheet has good flexibility and impact resistance, and has excellent impact resistance even under the condition that the thickness is 0.4-1.2 mm; due to the fact that the hollow glass beads are added, the surface density of the rubber sheet is only 0.3-0.8 kg / m, the rubber sheet is combined with the light structure wave-absorbing material, the overall weight is light, and the maneuverability of maneuvering equipment is improved. The impact-resistant structure wave-absorbing material not only has good electromagnetic wave absorption performance and impact resistance, but also is light in weight and high in environmental adaptability, and the preparation process is simple.

This invention discloses a composite current collector, its preparation method, an electrode, and a battery, belonging to the field of lithium-ion battery technology. The composite current collector provided by this invention includes: a porous conductive matrix comprising a polymer and a first conductive filler dispersed in the polymer, prepared by differential roller stretching; a conductive layer disposed on at least one surface of the porous conductive matrix; and the conductive layer comprising a second conductive filler and a binder. The composite current collector of this invention achieves a significant reduction in electrode resistivity while maintaining excellent mechanical properties, effectively resolving the performance contradiction between lightweight and conductivity in traditional composite current collectors. The assembled lithium-ion battery exhibits high energy density, high cycle stability, and high safety.

The wall multiplying power of the wood structure solid wall can be improved without additionally installing reinforcing materials or reinforcing materials or increasing the specific gravity and / or the plate thickness of gypsum surface materials. A gypsum-based solid surface material (10) for a wood structure solid wall is configured from a main material or a core material and a paper member covering at least the front and back surfaces of the main material or the core material, the main material or the core material being formed from a plate-shaped gypsum hardened body in which inorganic fibers and an organic-based strength reinforcing material are mixed, and being capable of exhibiting a nail side resistance of 500 N or more. The present invention relates to a solid-resistant surface material which has a surface density in the range of 6.5-8.9 kg / m2 and a compressive strength of 6.5 N / mm2 or more, exhibits a limit displacement ([delta] u) of more than 20 * 10 <-3 > rad and an initial stiffness (K) of 2.0 kN / 10 <-3 > rad or more in an in-plane shear test of a solid-resistant wall, and is capable of improving the plasticity ([mu]) not only by increasing the limit displacement and by decreasing the yield point displacement ([delta] v), but also by reducing the initial stiffness (K) of 2.0 kN / 10 <-3 > rad. Therefore, the wall multiplying power and the short-term reference shear endurance (P0) of the wood structure endurance wall can be effectively or efficiently improved.

The invention discloses an ultrathin carbon fiber felt and a preparation method thereof, and relates to the technical field of composite materials. According to the method, the fiber amount of the ultrathin carbon fiber felt is controlled by adopting the electrostatic flocking technology and controlling the flocking voltage and the flocking time, and due to the fact that the uniformity of the electric field is high and easy to control, the high-precision uniformity of the ultrathin carbon fiber felt can be achieved, and the ultrathin carbon fiber felt with lower surface density can be prepared. According to the invention, the problems of tedious procedures and environmental protection of current wet-process forming of the carbon fiber felt can be solved, and the problem of overhigh surface density of the ultrathin carbon fiber felt can be solved.

The present invention belongs to the technical field of secondary batteries, and specifically relates to a secondary battery diaphragm coating slurry, and a secondary battery composite diaphragm, and further discloses a preparation method thereof. The secondary battery diaphragm coating slurry of the present invention uses nanocellulose whisker materials with high wettability, high heat resistance and light weight, and high adhesion and low-cost PMMA materials as raw materials, while taking into account the advantages of nanofiber whisker materials and PMMA materials. The secondary battery diaphragm of the present invention forms a modified diaphragm by coating the slurry on the surface of a polyolefin base film, and the 180°C thermal shrinkage and surface density are significantly reduced, and the bonding force is greatly improved, which can improve the safety of the battery, improve the adhesion, and also realize the lightweight design of the battery cell.

The present invention discloses a low-frequency broadband flat-plate sound-absorbing structure, comprising a frame, a front panel and a back panel fixedly arranged on the upper and lower sides of the frame, and a sound-absorbing body enclosed by the frame, the front panel and the back panel for absorbing low-frequency noise; a plurality of sound-absorbing holes are arranged on the front panel, one side of the sound-absorbing holes faces the sound source, and the other side is connected to the sound-absorbing body. The sound-absorbing body is composed of a plurality of partitions arranged in parallel in the frame, one end of the partition is fixed to the inner wall of one side of the frame, and the other end is gap-matched with the inner wall of the other side of the frame; the partition divides the space in the frame into serpentine channels, and the channels are provided with frame inner walls for separation, and the channels between adjacent frame inner walls form a MIE-type resonance cavity. The present invention has a compact structure, light weight, low surface density, a wide low-frequency sound absorption band, and good low-frequency sound absorption performance.

This invention relates to a secondary battery, an electrode wetting method, and a method for preparing the secondary battery. From a product design perspective, this invention reduces the areal density and compaction density of the electrode, increases the number of stacked layers, establishes a correlation between electrode areal density, compaction, and the number of stacked layers and the electrode pore volume, and directionally increases electrode pores to provide channels and storage space for electrolyte penetration. Based on this, the electrolyte formulation is optimized, thereby improving electrolyte wettability and ultimately enhancing the battery's long-term cycle life and high-temperature storage performance.

This invention discloses a method for preparing a flexible PAN / TiO2 / rubber composite electromagnetic shielding film, characterized by the following steps: (1) using PAN and 6% TiO2 as precursors, a casting solution is prepared, and electrospinning is used to spin a 10μm~20μm film; (2) after pre-oxidation at 180℃~200℃ and carbonization at 1200℃~1500℃, a C@TiO2 electromagnetic shielding film is obtained; (3) using chloroprene rubber as a matrix, the C@TiO2 electromagnetic shielding film / rubber sheet is stacked layer by layer through dry lamination hot vulcanization method for 10 alternating times to obtain a flexible PAN / TiO2 / rubber composite electromagnetic shielding film.

The application provides a full-band three-dimensional wave-absorbing metamaterial, comprising a plurality of basic structure units arranged in a periodic array, wherein the basic structure unit comprises a first electromagnetic loss three-dimensional superstructure, a second electromagnetic loss three-dimensional superstructure, a third electromagnetic loss three-dimensional superstructure, a fourth electromagnetic loss three-dimensional superstructure, a fifth electromagnetic loss three-dimensional superstructure, a sixth electromagnetic loss three-dimensional superstructure and a metal back plate arranged in sequence from top to bottom; and a resistive frequency selective surface is loaded on each of the first electromagnetic loss three-dimensional superstructure, the second electromagnetic loss three-dimensional superstructure, the third electromagnetic loss three-dimensional superstructure, the fourth electromagnetic loss three-dimensional superstructure, the fifth electromagnetic loss three-dimensional superstructure and the sixth electromagnetic loss three-dimensional superstructure; the application has the following beneficial effects: the resistive frequency surface, the pure metal patch and the electromagnetic loss three-dimensional superstructure are combined for multi-dimensional coupling absorption design, so that the full-band absorption performance is realized in the L, S, C, X, Ku, K and Ka bands which have a high utilization rate at present, and a certain electromagnetic loss performance is still exhibited in the V and W bands; the thickness is relatively thin, the maximum oblique incidence angle is not less than 70 DEG, so that the demand of a thin-layer, low-area-density electromagnetic wave-absorbing material working in a full-band range at present is met.

The invention belongs to the technical field of production of non-woven cloth, and particularly relates to a production process and production equipment of non-film bulletproof cloth applied to manufacturing bulletproof inserting plates. Aiming at the defects in the prior art, the film-free bulletproof fabric production process provided by the invention comprises the following steps: (1) cleaning, carding, drying and flattening fibers; (2) flatly laminating the flattened tow sheet and a flat hot melt adhesive film on a laminating roller; (3) fully compounding the laminated fiber sheet and a hot melting mold on a hot pressing roller; (4) cooling the composite sheet fused with the hot melt film, and then calendaring and shaping by using a cold roll; (5) automatically cutting the cold-rolled single-layer film-free non-woven cloth into square blocks; and (6) overlapping the cut single-layer non-woven cloth according to 0 degree / 90 degrees, and pressing according to the required layer number of the plugboard. According to the production process and equipment, a film-free process route is adopted, the yarn content of the non-woven cloth is increased, and the bulletproof performance can be remarkably improved; no film restriction exists, and the pressing process is simpler; the film-free single-layer non-woven cloth is cut and then directly enters the insertion plate pressing process, so that the production process of 2UD non-woven cloth is reduced, the efficiency is improved, and the cost is reduced; through the operation, the purposes of removing the film in the plugboard (helmet), improving the yarn content, increasing the adhesive force, preventing the layer from falling off, improving the performance, improving the efficiency and reducing the cost are achieved.

In order to improve the lithium precipitation problem of a pole piece, the invention provides a battery cell and a battery, the battery cell comprises a positive plate and a negative plate, the positive plate comprises a positive current collector, a positive tab and a positive active material layer, the positive active material layer is arranged on at least one side of the positive current collector, and the positive tab is connected with the positive current collector; the negative plate comprises a negative current collector, a negative tab and a negative active material layer, the negative active material layer is arranged on at least one side of the negative current collector, and the negative tab is connected with the negative current collector; in the length direction of the negative plate, the coating surface density of the negative active material layer is gradually increased along the direction far away from the negative tab; and in any region of the battery cell, the ratio K of the coating surface density of the negative electrode active material layer to the coating surface density of the positive electrode active material layer at the corresponding position is more than or equal to 0.4 and less than or equal to 0.52.

The invention belongs to the technical field of microwave absorption, and particularly relates to a carbon-based magnetic composite material, a columnar structure microwave absorber and a preparation method and application of the columnar structure microwave absorber. According to the carbon-based magnetic composite material, a common waste biomass material serves as a carbon source, after high-temperature carbonization, an inherent porous structure of the biomass carbon material is reserved, a common commercial magnetic material is compounded with the carbon-based magnetic composite material, and the magnetic material is evenly distributed in the biomass carbon material; the composite material has the advantages of low cost, high yield, excellent wave absorbing performance and the like; and the preparation method of the composite material is simple, does not generate extra pollution waste materials, and can be used for mass production. The composite material is applied to preparation of the microwave absorber with the columnar structure, the unit size of the microwave absorber with the columnar structure is optimized, the wave absorbing performance of the microwave absorber with the columnar structure is effectively improved, meanwhile, the weight of the wave absorber is reduced, and the surface density of the microwave absorber with the columnar structure is effectively reduced.

The invention discloses a linear light lithium battery diaphragm and a preparation method thereof, the linear light lithium battery diaphragm comprises a base membrane and a coating on the base membrane, the coating is obtained by coating slurry, and the slurry comprises a silane coupling agent, carboxymethyl cellulose and rodlike aluminum silicate hydrate. The length of the rod-like hydrated aluminum silicate is 100-130 microns, and the width of the rod-like hydrated aluminum silicate is 200-600 nm. And the surface density of the diaphragm is effectively reduced by adding the rod-like hydrated aluminum silicate, so that the mass of the lithium ion battery is reduced. Meanwhile, the diaphragm disclosed by the invention also has relatively high liquid absorption, liquid retention capability and wettability, and the lithium ion battery has excellent cycle performance.

The utility model discloses a current collector, a battery monomer and a power device, the current collector comprises a foil material, the foil material is provided with a through hole, and the through hole is filled with a thermosensitive insulating material; the surfaces of the two sides, in the thickness direction, of the foil are coated with the first coating, and the first coating is configured to generate inert gas under the preset condition; and the second coating is coated on the surface of one layer, far away from the foil, of the first coating. According to the current collector disclosed by the utility model, the first coating capable of generating inert gas at high temperature is coated on the current collector, so that the pressure in the battery cell is increased, the anti-explosion valve can be opened in advance for heat dissipation, the violent degree of thermal runaway in the battery cell and the explosion risk are reduced, and the safety coefficient in the battery cell is improved; and the thermosensitive insulating material melts under the influence of temperature rise, expands in volume, flows out of the through holes and covers the surface of the foil, so that the surface of the foil is insulated, and the condition of short circuit is avoided.