2387 results about "Silicon based" patented technology

The invention belongs to the technical field of semiconductor devices, and particularly relates to an optical waveguide device based on a glass substrate, which comprises the glass substrate and a transition layer, an X silicon-based waveguide layer is arranged on the first surface of the transition layer, a heterogeneous material chip layer is integrated on the X silicon-based waveguide layer, the first surface of the X silicon-based waveguide layer is coated with a protective layer, and the protective layer is arranged on the first surface of the transition layer. The protective layer covers the glass substrate, the X silicon-based waveguide layer and the heterogeneous material chip layer at the same time; wherein the transition layer comprises an X element which is the same as that of the X silicon-based waveguide layer, through the above structure, the optical waveguide device with multiple layers of transition function areas is provided, the problems that the surface roughness of a large glass substrate is high, and the warping possibility is higher due to size effect amplification can be solved, and the optical waveguide device is suitable for large glass substrates. On the premise of fully utilizing the advantages of low cost and high performance of the glass substrate, the design of a large-size optical waveguide device for inhibiting packaging warping is realized.

The invention discloses a negative electrode interface modification material, a negative electrode plate, a positive electrode interface functional layer, a positive electrode plate, a solid-state battery and a power utilization device, and relates to the technical field of batteries, the negative electrode interface modification material comprises a first polymer matrix, a reinforcing filler, a conductive agent and a lithium salt, the modulus of the reinforcing filler is greater than 50 GPa. The tensile strength of the negative electrode interface modification material can be improved through the first polymer matrix, breakage of a negative electrode interface modification layer is reduced, interface impedance is reduced, meanwhile, the first polymer matrix can be matched with the expansion coefficient of a silicon-based material, and bulging of a negative electrode plate is reduced. The modulus of the reinforcing filler is greater than 50GPa, so that the modulus of the negative electrode interface modification layer can be improved, the expansion of the silicon-based active material is further inhibited, the conductive agent can relieve the problem that the flexible substrate interface of the copper foil and the negative electrode interface modification layer possibly causes unsmooth electron transmission, and the lithium salt can improve the ion conduction capability and reduce the interface impedance.

The invention discloses a multi-hydrogen bond enhanced fluorine-containing core-shell water-based binder as well as a preparation method and application thereof, and relates to the technical field of lithium ion silicon-based negative electrode binders. The preparation method comprises the following steps: dissolving methyl methacrylate, acrylonitrile and an emulsifier in water, carrying out a polymerization reaction to obtain a rigid core emulsion, adding acrylic acid long-chain ester, a fluorine-containing monomer and acrylamide, carrying out a mixing reaction to obtain a core-shell structure emulsion, mixing the core-shell structure emulsion with a sodium alginate solution, adding nano SiO2, and carrying out a polymerization reaction to obtain the high-temperature-resistant water-based acrylic emulsion. And after the reaction is finished, obtaining the multi-hydrogen bond enhanced fluorine-containing core-shell water-based adhesive. Through core-shell structure design and introduction of a multiple hydrogen bond network, the problem of bonding caused by volume expansion of the silicon negative electrode material in the charging and discharging process is successfully solved, the cycle life and stability of the battery are remarkably prolonged, meanwhile, the environment-friendly characteristic and the process simplicity are considered, and the preparation method is simple and convenient. And an efficient and sustainable development solution is provided for the field of lithium ion batteries.

The invention provides a secondary battery and a power utilization device, the secondary battery comprises a positive pole piece and a negative pole piece, a negative active layer of the negative pole piece comprises a silicon-based material, and a positive active layer of the positive pole piece comprises a lithium transition metal oxide and lithium-containing phosphate of an olivine structure, the lithium-containing phosphate comprises secondary particles I formed by primary particles I, pores exist among the primary particles I in the secondary particles I, and the secondary particles I are of a porous structure; and in the cross section of the secondary particles I, the area of the area filled with the primary particles I accounts for 60%-85%. The secondary battery prepared by the invention has both low-temperature performance and energy density.

The invention provides a silicon-based material and a preparation method thereof, a negative pole piece and a solid-state battery. The silicon-based material comprises an inner core and a surface coating layer, the inner core comprises a silicon-based negative electrode material, the surface coating layer is a carbon fluoride layer, the carbon fluoride layer internally comprises Li-M, LiF and LiX, M represents a metal element and is selected from at least one of Ag, Mg, Zn and Al, and X represents a non-metal element and is selected from at least one of N, S and P. The silicon-based negative electrode material is used as a core, the surface of the silicon-based negative electrode material is coated with the carbon fluoride layer, and the Li-M alloy / LiF / LiX composite lithium compound is introduced into the carbon fluoride layer, so that triple effects of ion-electron double-conduction network construction, interface chemical stabilization and mechanical buffer enhancement are achieved; and the chemical stability of an interface between the silicon negative electrode and sulfide solid electrolyte is improved while the rate capability of the negative electrode is improved and the expansion and shrinkage of the silicon negative electrode are relieved, and the cycling stability is improved.

The invention belongs to the technical field of treatment of special gas packaging gas cylinders, and particularly relates to a treatment method and application of a mixed gas packaging gas cylinder, and the treatment method comprises the following steps: S1, filling a packaging gas cylinder with monosilane mixed gas, maintaining the pressure, and then carrying out vacuum-pumping treatment; s2, filling the dry compressed air, maintaining the pressure, then vacuumizing, and repeatedly filling the dry compressed air, maintaining the pressure and vacuumizing for 2-3 times; and S3, nitrogen is refilled, then vacuumizing treatment is carried out, and nitrogen filling and vacuumizing are repeatedly carried out 5-8 times. S4, target mixed gas with the pressure of 50 psig-150 psig and the concentration of 50-100 times is filled and stored for 24-168 h, then the target mixed gas in a mixed gas packaging gas cylinder is analyzed, if the target mixed gas is smaller than or equal to three times of the index before filling, it is judged that treatment is qualified, and otherwise the steps S1-S3 are repeated. The interior of the gas cylinder is pretreated, a silicon-based isolation layer is formed on the inner wall of the gas cylinder, and the corrosion resistance of the interior of the gas cylinder is improved.

The invention relates to the technical field of microelectronics, semiconductors and communication, and discloses a radio frequency switch chip, and the circuit structure of the radio frequency switch chip comprises a transformer type differential inductor T-L1, a transformer type differential inductor T-L2, a capacitor C1, an NMOS transistor M1, an NMOS transistor M2, a gate resistor RG1, and a gate resistor RG2. The radio frequency switch chip provided by the invention adopts a differential structure, so that the parasitic inductance effect of a grounding key and a wire during packaging and testing can be eliminated, and the insertion loss and the isolation performance are improved; compared with a single-end port, the lower impedance of the differential port is more beneficial to improving the power capacity of the switch; the differential structure allows the transformer type differential inductor to use differential signal characteristics, the equivalent quality factor of the inductor is improved, and the circuit performance is improved; the differential structure can improve the linearity of the circuit, especially the second-order intermodulation effect; the differential structure can be compatible with a modern silicon-based CMOS radio frequency system, and an additional balun is not needed for signal conversion.

The invention belongs to the technical field of secondary batteries, and discloses a polyurethane acrylate emulsion and a secondary battery. The polyurethane acrylate emulsion comprises water and a polymer dispersed in the water; the polymer comprises a core and a shell, the shell covers the core, the core comprises water, and the shell comprises urethane acrylate; the polyurethane acrylate comprises a polyurethane unit and a polyacrylate unit, and the polyacrylate unit comprises an organic silicon chain segment; on the basis of the mass of the polyurethane acrylate, the mass content of the organic silicon chain segment is 0.1%-10%. The polyurethane acrylate emulsion provided by the invention has the characteristics of high bonding strength, electrolyte corrosion resistance and good dispersity to a conductive agent, and when the polyurethane acrylate emulsion is used as a silicon-based negative electrode binder, the polyurethane acrylate emulsion can effectively cope with large volume change of a silicon-based material, the problem of interface failure of a silicon-based negative electrode is solved, and the cycle performance and the dynamic performance of a battery are improved.

The invention discloses a composite solid electrolyte layer, a preparation method and application, the composite solid electrolyte layer comprises a porous membrane laminated on a negative pole piece, and pores in the porous membrane and gaps between the porous membrane and the negative pole piece are filled with in-situ generated polymers. Inorganic solid electrolyte is also dispersed in the porous membrane, and lithium salt is dispersed in the polymer and the porous membrane. The composite solid electrolyte layer is obtained through in-situ polymerization of a polymer in pores in the porous membrane and gaps between the porous membrane and the negative electrode plate, and a novel interface structure with the electrode-electrolyte integration characteristic is constructed. By adopting a collaborative optimization strategy of a polymer matrix and inorganic filler double-crosslinking network system and an interface stable layer, the volume effect problem of a silicon-based negative electrode, the electrolyte interface impedance problem and the battery safety problem can be solved at the same time, so that the cycling stability and the rate capability of the lithium ion battery are remarkably improved.

The application belongs to the technical field of batteries, and particularly relates to a silicon-carbon negative electrode material and a preparation method and application thereof. The method comprises the following steps: preparing a porous carbon fiber membrane loaded with a metal catalyst; preparing a dispersion solution of a nano-silicon-based material, and distributing the nano-silicon-based material into the porous carbon fiber membrane to obtain a composite porous carbon fiber membrane; and performing thermal chemical vapor deposition on the composite porous carbon fiber membrane in an inert atmosphere containing a carbon source, growing carbon nanofibers and vertical graphene on the surface of the composite porous carbon fiber membrane, and obtaining a silicon-carbon negative electrode material. Through a synthesis route of thermal chemical vapor deposition (T-CVD), the synthesis process is optimized, and a multi-level three-dimensional network structure of carbon nanofibers and vertical graphene is constructed to enhance the electrical conductivity of the silicon-carbon negative electrode material, accelerate carrier transmission, improve the interface contact performance between the silicon-based material and the carbon material, improve the loading capacity of the nano-silicon-based material, inhibit the volume expansion of the nano-silicon-based material, and improve the structure and cycle stability of the nano-silicon-based material.

A method and an apparatus for conformal boron doping of a three-dimensional structure. The method comprises: removing an oxide layer from a surface of a silicon-based three-dimensional (3D) substrate; forming, after removing the oxide layer, a first group of stacked films on a surface of the silicon-based three-dimensional substrate; forming a second group of stacked films on a surface of the first group of stacked films away from the silicon-based 3D substrate; depositing an aluminum oxide passivation layer on a surface of the second group of stacked films away from the first group of stacked films; and boron-doping the silicon-based 3D substrate through laser annealing or rapid thermal annealing, where the laser annealing or the rapid thermal annealing drives boron dopants, which comprises boron oxide, into the silicon-based 3D substrate via an auxiliary layer.

The application discloses a dynamic roller pressing forming device for a gradient-pore diaphragm for a silicon-based negative electrode, comprising a modular coating unit, a multi-shaft roller pressing machine group and a partitioned annealing cavity arranged in sequence, the modular coating unit comprises a slit coating mechanism, a spray coating mechanism and a micro-gravure coating mechanism arranged in sequence, the multi-shaft roller pressing machine group comprises a main pressing roller and a supporting roller matched with the main pressing roller, and a dynamic pressure feedback system is arranged on the main pressing roller; and the application further discloses a method for preparing a gradient-pore high-molecular diaphragm by using the forming device. The device is provided with the main pressing roller of the multi-shaft roller pressing machine group and the partitioned annealing cavity, and the dynamic pressure feedback system is arranged on the main pressing roller, so that the accurate matching between the pore structure and the expansion behavior of the silicon-based negative electrode is realized, the stress buffering capacity and the ion transmission efficiency of the diaphragm are improved, and the device is suitable for the technical field of lithium ion battery materials.

The application discloses a high-reliability high-power three-dimensional heterogeneous integrated radio frequency antenna integrated microsystem, comprising a DPC substrate, a copper-based three-dimensional structure, a two-stage SiC adapter plate, a bare chip, a radio frequency circuit, a passive device and an antenna interface; wherein the DPC substrate is used for realizing integrated three-dimensional heterogeneous integration of the microsystem; the copper-based three-dimensional structure comprises a three-dimensional coaxial transmission structure and a three-dimensional packaging frame structure, and is used for realizing vertical transmission of high-power radio frequency signals and air-tight packaging of the microsystem; the two-stage SiC adapter plate is used for realizing a 2.5D*2 five-layer ultra-high-density mixed three-dimensional stacking architecture; the bare chip comprises a silicon-based Fan-out multifunctional bare chip, a power management bare chip, a power amplifier bare chip and a receiving bare chip; the radio frequency circuit comprises a radio frequency transmitting circuit and a radio frequency receiving circuit. The application forms a complete integrated air-tight packaging microsystem, and simultaneously realizes high reliability, high-density integration and high-power heat dissipation.

The invention discloses a comprehensive two-dimensional vertical structure metal-semiconductor field effect transistor and a preparation method thereof. A source electrode, a lower isolation layer, a drain electrode and an upper isolation layer which are vertically stacked are formed on the surface of a substrate, an inclined side wall is formed, a channel covers the inclined side wall, a grid electrode and the channel are self-aligned, and a semi-metal grid electrode and a semiconductor channel are in direct contact to form a Schottky junction; based on a comprehensive two-dimensional material system, the Fermi pinning effect and unintentional doping are effectively inhibited, and the performance of the device is optimized by optimizing the grid control capability and the electric contact performance; a gate dielectric layer is not arranged, so that the problems of electrical performance deterioration and the like under a limit miniature scale are avoided; the integration density of the device is improved and the research and development and manufacturing cost is controlled while excellent performance is kept; the channel length and the contact length are synchronously and accurately reduced by utilizing a side wall vertical structure; the method is applied to the industrial application fields of next-generation integrated circuit chips, high-density memories, flexible and wearable electronics and the like which break through the silicon-based physical limit.

The invention provides a silicon-based panel bonding method, which relates to the technical field of silicon-based panel manufacturing, and comprises the following steps of: calibrating a first platform unit through double cameras of an alignment unit to eliminate a mechanical movement error, respectively shooting a target piece and a terminal area mark point to avoid a switching error, and eliminating a positioning deviation in combination with multi-direction increment calibration; micron-sized alignment is realized, and the problem of alignment deviation of the silicon-based panel is solved; in addition, in the initial positioning link, defective target pieces are screened in advance, the scrap risk of semi-finished products is reduced, and the bonding yield and efficiency are improved.

The invention discloses a method for preparing a graded porous structure Si-C composite material based on a double-template method, and belongs to the technical field of lithium ion battery negative electrode materials. The method specifically comprises the following steps: (1) silicon waste pretreatment; (2) preparing a double-template / carbon source precursor mixture; (3) sealing, transferring and charging; (4) carrying out in-situ reduction, carbonization and pore forming; (5) template removal and post-treatment; (6) solvent replacement; and (7) drying. The invention relates to a method for preparing a carbon-coated silicon-based composite material (Si-C) with a hierarchical porous structure by using silicon waste (SSW) generated by diamond wire cutting in the photovoltaic industry as a raw material through an innovative synergistic double-template method. When the material prepared by the method is used for a lithium ion battery negative electrode, the key problems of serious volume expansion and short cycle life of a silicon-based material can be solved, and meanwhile, high-added-value resource utilization of solid waste is realized.

The invention provides a secondary battery and an electrochemical device, and relates to the field of electrochemical energy storage. The secondary battery comprises an electrolyte and a negative pole piece, the electrolyte comprises a first substance, and the first substance comprises at least one of compounds with a structure as shown in a formula I; the negative pole piece comprises a negative pole material layer; the negative pole material layer comprises carbon black, single-walled carbon nanotubes, carbon fibers and a silicon-based material; the silicon-based material comprises at least one of a silicon-carbon material, a silicon-oxygen material, a silicon alloy material and a pure silicon material. According to the secondary battery, the electrolyte is designed to contain a compound with a specific structure as shown in the formula I, the mass content of the compound is controlled to be 0.5%-30%, and meanwhile, the negative electrode material layer comprises carbon black, single-walled carbon nanotubes and carbon fibers, so that the high-temperature storage performance, the cycle performance and the high-low-temperature fast charging performance of an electrochemical device containing a silicon negative electrode are remarkably improved.

The invention relates to the technical field of secondary batteries, and discloses a secondary battery, a negative active layer in a negative plate comprises a negative active material and a negative adhesive, the negative active material comprises a silicon-based material, the negative adhesive comprises a polymer, and the raw material of the polymer comprises a hard segment monomer and a soft segment monomer; the electrolyte comprises carbonic ester substances and lithium salt; on the basis of the total mass of the raw materials of the polymer, the mass content of the soft segment monomer is r%; on the basis of the total mass of the electrolyte, the mass content of the carbonic ester substance is t%; t / r is greater than or equal to 0.234 and less than or equal to 1.770. According to the secondary battery provided by the invention, the chemical structure of the adhesive is optimized and the composition of the electrolyte solution is adjusted, so that the excellent electrochemical performance of the battery is ensured, the swelling effect of the electrolyte on the adhesive is reduced, the cycle life of the battery is prolonged, and the safety of the battery is improved.

The invention discloses a porous silicon-carbon composite negative electrode material, a one-step preparation method, a lithium ion battery and application, and belongs to the technical field of lithium ion battery materials, the method comprises the following steps: mixing a silicon source, magnesium powder, a carbon source and a soluble pore forming agent to obtain mixed powder; performing high-energy mechanical ball milling on the mixed powder in an inert atmosphere, and performing acid pickling, high-temperature carbonization treatment, cooling, water washing, suction filtration and drying to obtain the porous silicon-carbon composite negative electrode material; the porous silicon-carbon composite negative electrode material comprises a porous shell formed by amorphous porous carbon and a porous core formed by silicon nanoparticles embedded in the porous shell, the mechanical collision energy generated in the high-energy mechanical ball milling process triggers the low-temperature magnesiothermic reduction reaction between the silicon source and the magnesium powder, the carbon source is attached to the surfaces of silicon particles while the silicon particles are generated, and silicon synthesis, carbon coating and pore forming are synchronously achieved. The silicon-based negative electrode has the advantages of high initial coulombic efficiency, high specific capacity, excellent cycle stability and rate capability, and effectively solves the problems of volume expansion and large-scale preparation of the silicon-based negative electrode.

The application provides a negative electrode material and a preparation method thereof and a secondary battery, and relates to the technical field of battery materials. The negative electrode material comprises a silicon-based inner core and a carbon layer coated on the surface of the silicon-based inner core, wherein the silicon-based inner core comprises nanosilicon and a silicate containing a metal element M; the negative electrode material is subjected to section analysis and energy spectrum analysis, and meets the conditions of k1<=10, k2<=5 and 0.1 The preparation method of the negative electrode material comprises the following steps: heating and evaporating pre-disproportionated silicon monoxide material and M metal source material to obtain silicon monoxide gas and metal source gas; mixing and condensing the two kinds of gas to obtain an inner core material; and performing carbon coating treatment to obtain the negative electrode material. In the negative electrode material prepared by the application, the metal silicate effectively separates the nanosilicon domain and the silicon oxide domain, and is uniformly distributed, and the negative electrode material has high initial efficiency and excellent cycle performance.

The invention relates to an artificial SEI material, a negative electrode material and application thereof, the artificial SEI material comprises a hydrophobic flexible polymer and a hydrophobic rigid polymer, the hydrophobic flexible polymer and the hydrophobic rigid polymer form a three-dimensional interpenetrating network structure, and the deformation coefficient K of the artificial SEI material is 1 < = K < = 600; wherein K = WL / Q, and W is the mass ratio of the hydrophobic flexible polymer to the hydrophobic rigid polymer; q is the tensile strength, MPa, of the artificial SEI material; l is the elongation at break,% of the artificial SEI material. The surface of a silicon-based material is coated with the artificial SEI material, gas production can be effectively reduced, and volume expansion of a silicon-based core can be inhibited, so that the performance of a battery is improved.

The invention discloses an MOMES accelerometer based on light intensity modulation, and belongs to the technical field of micro-electro-mechanical systems and inertial measurement. The MOMES accelerometer comprises a silicon-based base, a mass block, a fixed anchor point, an elastic beam assembly and a double-photoelectric detector. The mass block is hung on the silicon-based base through the elastic beam assembly and the fixed anchor point, the fixed anchor point is fixed on the surface of the silicon-based base, and the fixed anchor point is connected with the elastic beam assembly; the center of the mass block is provided with a light hole which completely penetrates through the thickness direction. And the double photoelectric detector is fixed on the surface of the silicon-based base and is positioned in a light projection area of the light hole. When the accelerometer is subjected to the action of external acceleration along the Y-axis direction, the rectangular mass block generates displacement relative to the silicon-based base, so that the light intensity distribution of a light spot projected by the light hole on the double photoelectric detector generates differential change; the accelerometer has the advantages of high sensitivity, strong anti-interference capability, good process compatibility and the like, and is suitable for high-precision inertial measurement.

According to the silicon-based OLED micro display screen, an OLED organic material layer emits white light under electric driving, intelligent judgment is performed according to display content, an optimal working mode is automatically selected, when high-saturation pure color needs to be displayed, the mode is switched to a pure color transparent mode, at the moment, a super-surface optical separation layer keeps the transparent characteristic, and the display quality is improved. The white light is directly transmitted to the color film unit with the corresponding color; when mixed colors need to be displayed, a mixed color separation mode is started, incident white light is separated into red primary light, green primary light and blue primary light according to visible spectrums, the light is accurately guided to the corresponding RGB color film units according to a preset optical path, finally, the color light which is accurately separated and guided is output through the corresponding color films, and finally a high-brightness and low-power-consumption full-color picture is synthesized. The super-surface optical separation layer is additionally arranged between the white light OLED light-emitting layer and the color filter, so that the display optical utilization efficiency is greatly improved.

The utility model is suitable for the photovoltaic technology field, and provides a back contact cell, a cell assembly and a photovoltaic system, the back contact cell comprises a silicon substrate, and a first area, a spacing area and a second area are alternately arranged on the backlight surface of the silicon substrate along a first direction; the first tunneling layer is stacked in the first region; the first doping layer is stacked on the first tunneling layer; the second tunneling layer is stacked in the second region and a preset region of the interval region, and extends along the side wall, close to the first region, of the preset region to be in contact with one side, close to the second region in the first direction, of the first doping layer; the insulating medium layer is arranged on the first doping layer in a stacked mode, and the insulating medium layer is provided with an extending part extending to the interval area in the first direction in a preset area of the interval area; the second doped layer covers the first portion and the wrapping portion over the second tunneling layer. The efficiency loss caused by electric leakage contact can be reduced while the hot spot resistance of the back contact battery is improved.

The invention discloses a double-layer nano silicon-based material as well as a preparation method and application thereof, and belongs to the technical field of energy storage. The double-layer nano silicon-based material sequentially comprises a core layer, a first shell layer and a second shell layer from inside to outside, the core layer is nano silicon, the first shell layer is a silicon carbide layer with the thickness of 1.1-5.0 nm, and the second shell layer is a carbon layer with the thickness of 1.1-4.2 nm; a carbon-silicon bond is formed between the core layer and the first shell layer, and a carbon-silicon bond is formed between the first shell layer and the second shell layer. On one hand, silicon volume expansion is physically limited through a high-strength rigid framework; on the other hand, an ion / electron synergistic conduction functional interface layer is constructed, and unification of stress buffering, interface stability and rapid dynamics is achieved.

The invention provides a battery, the battery comprises a negative plate, a positive plate and an electrolyte, the negative plate comprises a negative current collector and a negative active layer located on the surface of one side or two sides of the negative current collector, the negative active layer comprises a silicon-based material, and in the negative active layer, the weight ratio of silicon element is 2-45%; the electrolyte comprises difluoroethylene carbonate, fluoroethylene carbonate and a phosphazene compound, and in the electrolyte, the weight ratio of the difluoroethylene carbonate to the fluoroethylene carbonate is 0.002-0.4; the molecular structure of the phosphazene compound comprises cyano groups and phosphorus atoms, and the weight ratio of the phosphazene compound in the electrolyte is 0.1-5%. According to the battery, a firm and flexible SEI film can be formed on the surface of the silicon-based negative electrode, repeated breakage of the SEI film is reduced or even avoided, meanwhile, the concentration of HF can be reduced, the internal short circuit and self-discharge risks of the battery are reduced, and the long-cycle stability and the high-temperature cycle performance are improved.

The invention relates to the technical field of batteries, and provides a battery. The battery comprises a positive plate, a negative plate and electrolyte, the negative plate comprises a negative current collector and a negative active material layer arranged on at least one side surface of the negative current collector, and a plurality of concave parts are arranged on the surface of one side, far away from the negative current collector, of the negative active material layer; the negative active material layer comprises a silicon-based material and a carbon-based fiber material, and the length-diameter ratio of the carbon-based fiber material is 10-500; the electrolyte comprises a first solvent, and the first solvent comprises ethyl difluoroacetate; based on the total mass of the electrolyte, the mass ratio of the first solvent is 20.2%-75.1%. According to the battery, the cycling stability under high-voltage and high-temperature working conditions can be improved while the quick charging performance is ensured.

The invention relates to the technical field of batteries, in particular to an electrode assembly, a preparation method and a lithium ion battery, the electrode assembly comprises a positive pole piece, a negative pole piece and a diaphragm, the positive pole piece comprises a positive current collector and a positive active material layer, and the positive active material layer comprises a positive active material layer and an inorganic coating; the positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer comprises a positive electrode active material, and the positive electrode active material comprises a ternary positive electrode material of which the core nickel content is more than 80 at% and the shell manganese content is 10-20 at%; the negative active material comprises silicon-based active particles and a three-dimensional elastic conductive network layer coating at least part of the surface of the silicon-based particles, and the positive active material and the negative active material are improved, so that various properties of the electrode assembly are good and stable, the overall electrical property and safety of the battery are improved, and the cycle life of the battery is prolonged.

Novel electrolyte compositions for lithium ion energy storage devices with silicon-based electrode materials have improved stability. The electrolyte composition may be used in an energy storage device that includes a first electrode and a second electrode, where at least one of the first electrode and the second electrode is a silicon-based electrode; a separator between the first electrode and the second electrode; and the electrolyte composition.

This application provides a negative electrode active material, a secondary battery, and an electrical device. The silicon-carbon negative electrode material includes a silicon-carbon composite material, which comprises a first silicon-carbon composite particle and a second silicon-carbon composite particle. The first silicon-carbon composite particle comprises a first carbon matrix with a porous structure and a first silicon-based material disposed within the porous structure of the first carbon matrix. The second silicon-carbon composite particle comprises a second carbon matrix with a porous structure and a second silicon-based material disposed within the porous structure of the second carbon matrix. Furthermore, the mass percentage of silicon in the first silicon-carbon composite particle is greater than the mass percentage of silicon in the second silicon-carbon composite particle. This silicon-carbon negative electrode material exhibits both high specific capacity and good cycle stability, thereby improving the energy density and cycle performance of the battery.