58results about How to "High magnification" patented technology

The invention provides an optical imaging lens, the optical imaging lens has eight lenses with focal power, and the optical imaging lens comprises a lens group, a spacing element group and a lens barrel group, the effective focal length f7 of the seventh lens and the interval EP67 between the sixth spacing element and the seventh spacing element in the direction of the optical axis of the optical imaging lens meet the following condition: f7 / EP67 is more than or equal to-8.25 and less than or equal to-6.82; the curvature radius R15 of the object side face of the eighth lens and the inner diameter d7m of the image side face of the seventh spacing element meet the condition that R15 / d7m is larger than or equal to 1.31 and smaller than or equal to 2.28. The multi-group optical imaging lens solves the problems that in the prior art, the rear end forming yield of the multi-group optical imaging lens is low, and stray light is serious.

The invention provides a positive pole piece, a preparation method thereof and a lithium ion battery. The positive pole piece comprises a positive current collector and a negative current collector, the first active coating is arranged on the surface of at least one side of the positive electrode current collector; the raw materials of the first active coating comprise a first main material, a first conductive agent and a low-swelling binder; the second active coating is arranged on the surface of one side, relatively far away from the positive electrode current collector, of the first active coating; and raw materials of the second active coating comprise a second main material, a second conductive agent and a high-swelling binder. Different types of binders are introduced into the first active coating and the second active coating, so that the tortuosity and porosity of the pole piece are changed, the diffusion rate of lithium ions is effectively improved, the concentration polarization of the surface layer of the pole piece is reduced, and the rate and cycle performance of the battery are remarkably improved. Particularly, the positive pole piece can achieve the goal of improving the multiplying power and the cycle performance without increasing the proportion of the conductive agent.

The invention belongs to the field of energy storage of new energy materials, and relates to an asphalt-based hard carbon negative electrode material with high initial efficiency, high magnification and high capacity and a preparation method thereof. The hard carbon negative electrode material has a long and complete carbon layer edge, the specific surface area is 2-8 m < 2 > / g, and / or the aperture of the hard carbon negative electrode material is 1-12 nm. The method comprises the following steps: pre-oxidizing asphalt, mixing the pre-oxidized asphalt with a fusion repair-decomposition etching dual-function additive, and carrying out two-step high-temperature carbonization treatment in an inert atmosphere: melting metal salt in the first step of high-temperature carbonization so as to catalytically connect an edge carbon layer and repair defects; in the second step of high-temperature carbonization, the metal salt is decomposed to generate gas, pores are formed in the material, and the temperature of the first step of high-temperature carbonization is controlled to only melt the metal salt but not decompose the metal salt. Through single-additive two-step reaction, the first coulombic efficiency, the rate capability and the capacity are improved at the same time.

The invention discloses a sulfur-doped composite hard carbon material as well as a preparation method and application thereof. Sulfonated resin is used as a carbon source and a sulfur source, and non-metal sulfur atoms with the atomic radius larger than that of carbon are doped in situ, so that the carbon layer spacing of hard carbon is increased, and the rate capability of the hard carbon is improved; and the sulfonated resin is subjected to surface pre-coating modification by using a cheap biomass carbon source, so that the specific surface area and defect sites of hard carbon are reduced, the number of closed pores is increased, and the specific capacity and the first coulombic efficiency of the hard carbon are improved.

The invention provides a positive electrode material, a positive electrode plate and a secondary battery. The positive electrode material contains an element M, the element M is selected from at least one metal element in IA group and IIA group in the periodic table of elements, the distribution of the element M in particles meets the condition that X2 / X1 is greater than or equal to 1.2 and less than or equal to 20, X1 is the concentration of the element M in the central region of the particles, X2 is the concentration of the element M in the surface region of the particles, and X3 is the concentration of the element M in the surface region of the particles. The surface of the positive electrode material contains nitrate ions, the content of the nitrate ions is N1, and N1 is more than or equal to 10ppm and less than or equal to 100ppm. The positive electrode material disclosed by the invention has relatively high structural stability and relatively small number of microcracks, a stable interface protection layer can be formed on the surface of the positive electrode material, and side reaction between an electrolyte and the surface of the positive electrode material is reduced, so that the capacity and the cycle performance of a battery prepared from the positive electrode material are comprehensively improved, and meanwhile, the gas production performance is improved.

The invention provides an optical imaging lens, the optical imaging lens has eight lenses with focal power, and the optical imaging lens comprises a lens group, a spacing element group and a lens barrel group, the effective focal length f4 of the fourth lens and the interval EP34 between the third spacing element and the fourth spacing element in the direction of the optical axis of the optical imaging lens meet the condition that f4 / EP34 is greater than or equal to-10.62 and less than or equal to-5.20; the curvature radius R8 of the image side face of the fourth lens, the outer diameter D4s of the object side face of the fourth spacing element and the inner diameter d4s of the object side face of the fourth spacing element meet the condition that R8 / (D4s-d4s) is larger than or equal to 0.87 and smaller than or equal to 1.65. The multi-group optical imaging lens solves the problems that the middle group of the multi-group optical imaging lens in the prior art is unstable and stray light is serious.

The invention relates to a microscopic imaging system and laser precision machining equipment, the microscopic imaging system comprises an objective lens group and an eyepiece group, and the objective lens group and the eyepiece group are arranged in sequence along an optical axis from an object plane to an imaging plane. Along the optical axis from the object plane to the imaging plane, the objective lens group sequentially comprises a first lens with positive focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with positive focal power, a seventh lens with positive focal power and an eighth lens with positive focal power; the ninth lens is provided with positive focal power, the tenth lens is provided with negative focal power, the eyepiece group has the amplification factor not less than 10 times, and the sum of the total optical length TTL1 of the objective lens group and the total optical length TTL2 of the eyepiece group is not less than 178.4 mm. Therefore, the microscopic imaging system provided by the invention has a relatively large amplification factor and also has a relatively good optical total length.

This invention relates to a boron-doped multi-element polyanionic sodium-ion battery cathode material and its preparation method, comprising the following steps: [The method involves] mixing Na₄Fe₂O₃ with... 3‑X B X (PO4) 2‑Y (SiO4) Y The stoichiometric ratio of P2O7 is determined by adding ferrous source, boric acid, sodium source, phosphorus source, and silicon source to water, followed by the addition of carbon source and mixing thoroughly to obtain a mixed slurry; wherein 0.2≤X≤0.5, 0<Y≤1; the mixed slurry is then ground to obtain a sand-milled slurry; the sand-milled slurry is dried to obtain precursor powder; under a protective atmosphere, the precursor powder is sintered at 450~550℃ to obtain boron-doped multi-element polyanion sodium-ion battery cathode material. The introduction of boron and silicon elements in this invention helps reduce raw material costs, improve the electrochemical performance of the material, especially enhancing the structural stability, rate performance, and cycle life of the cathode material, and also lowers the sintering temperature, meeting the requirements for cost reduction and efficiency improvement.

The invention provides a method for synthesizing 6-aminocapronitrile from caprolactam. The method comprises the following steps: a gasification device is sequentially provided with a uniform distribution part, an efficient dispersion part, a high-temperature gasification part and an in-situ separation part from top to bottom; liquid-phase caprolactam is injected from the top end of the gasification device, and ammonia gas is injected through the efficient dispersion part; in the efficient dispersion part, liquid-phase caprolactam is broken in a first circular tube nest under the shearing action of gravity and ammonia gas to form liquid drops, and after high-temperature gasification, a gas phase is output from the side part of the gasification device, then enters the reactor filled with the monolithic catalyst from the bottom of the reactor, reacts through the monolithic catalyst and is output from the top of the reactor. According to the invention, caprolactam can be efficiently gasified, coking is not easy to generate, the retention time of a gas-phase reactant in the reactor can be accurately controlled, the reaction efficiency is greatly improved, the discharge amount of wastes in the production process of hexamethylenediamine is reduced, the cost is reduced, the economic benefit is improved, and a guarantee is provided for green, environment-friendly and safe production.

The invention relates to the technical field of power electronic direct-current converters, in particular to an input and output common-ground high-gain boost converter which comprises a direct-current voltage source Vin, diode components D0-D4, capacitor components C0-C4, a first coupling inductor L1, a second coupling inductor L2, a first mosfet tube S1, a second mosfet tube S2 and a resistor R. The two main loops operate in a staggered mode, so that input current is continuous, input current ripples are small, relatively stable energy is continuously provided for the circuit, the voltage multiplication unit is adopted, the amplification factor of the circuit is increased, the duty ratio of the mosfet tubes S1 and S2 is adjusted, and small current ripples can be kept even under the condition that the boost factor is large. The device has the advantages of high step-up ratio, low device stress, high efficiency, easiness in control and implementation, lower cost and the like, and is suitable for a new energy power generation scene needing high direct current bus voltage grid-connected output under a low input voltage condition.

This invention provides a halide solid electrolyte and its preparation method, belonging to the field of solid electrolyte technology. First, alkylphosphonic acid is reacted with lithium carboxylate to prepare lithium-ionized alkylphosphonic acid. Then, the lithium-ionized alkylphosphonic acid is mixed with a halide electrolyte, and the mixture is dispersed in a solvent, stirred, filtered, and dried to obtain a halide solid electrolyte coated with lithium-ionized alkylphosphonic acid. This invention constructs a dense, uniform hydrophobic protective layer on the surface of halide electrolyte particles through in-situ coating with long-chain lithium alkylphosphonate, effectively isolating moisture and oxygen from the environment and significantly improving the air stability of the halide electrolyte. Simultaneously, this coating layer helps reduce the interfacial impedance between the electrolyte and electrode materials, optimizing the overall ionic conductivity of the material.

The application provides a flaky flower-like single-crystal sodium vanadium oxyfluorophosphate / carbon composite material, a preparation method thereof and a sodium ion battery. The flaky flower-like single-crystal sodium vanadium oxyfluorophosphate material is prepared through a hydrothermal reaction. A surfactant is used to control the crystal face growth direction in the material synthesis process, so that the sodium vanadium oxyfluorophosphate grows to form a flaky flower-like single-crystal structure, and then the ion transmission distance is shortened, the ion kinetic characteristics of the material can be effectively improved, and on the basis of ensuring the structural stability of the material, that is, the cycle performance, the rate characteristics of the material are effectively improved. Through carbon coating, the electronic conductivity of the surface of the material particles is improved, and the capacity rate performance of the material is effectively improved.

The application relates to the field of carbon nanotube catalyst materials, and specifically discloses a catalyst and a preparation method thereof, an array type carbon nanotube and a preparation method thereof. A catalyst is formed into a sheet-shaped nanocrystalline grain, and the sheet-shaped nanocrystalline grain comprises at least one kind of microwave active metal ion. The preparation method of the catalyst comprises the following steps: S1, microwave-assisted reaction; S2, standing and aging; and S3, calcination treatment. An array type carbon nanotube is prepared by catalysis of the catalyst, the array type carbon nanotube has a plurality of unit carbon nanotube bundles, the unit carbon nanotube bundle comprises a plurality of carbon nanotubes which are intertwined and have a tube length greater than 1 mu m, and the tube diameter of the unit carbon nanotube bundle is 0.2-2 mu m. The carbon nanotube prepared by catalysis of the catalyst has a consistent length-diameter ratio, good orientation and high purity, so that the excellent performance of the carbon nanotube can be brought into play.

The invention provides a graphene / activated carbon composite material and a preparation method and application thereof, and belongs to the technical field of nano materials, the graphene / activated carbon composite material comprises a carbon matrix and a two-dimensional sheet material covering the carbon matrix; the carbon matrix is an activated carbon material and is a carbon material prepared by performing high-temperature pyrolysis on magnesium citrate in a high-temperature self-propagating reaction process; the two-dimensional sheet material is a graphene material and is a few-layer carbon material which is prepared by converting CO2 through a high-temperature self-propagating reaction and is formed by arranging carbon atoms according to a honeycomb-shaped two-dimensional lattice. According to the invention, graphene is used as a conductive and structural dual skeleton; and a hierarchical pore structure is constructed by utilizing gas production and template effect in the reaction process, so that the electrochemical performance of the active carbon positive electrode is improved. And a proper amount of graphene can provide more active sites and maintain the structural stability at the same time, so that the specific capacity and the cycle life are remarkably improved and prolonged, and the material has a wide application prospect and is particularly suitable for preparing a high-performance lithium ion capacitor positive electrode material.

This invention relates to the field of sodium-ion battery technology, and discloses a sodium-ion cathode material, its preparation method and application, a sodium-ion battery, a sodium-ion battery pack, and a device. The sodium-ion cathode material includes a matrix and a coating layer covering the matrix; the matrix has the composition shown in Formula I: Na 1‑x [Ni y Mn z M u Ti v O2 Formula I; the coating layer has the composition shown in Formula II: Na 2‑β Ti 6‑α M′ α O 13 Formula II. This sodium-ion cathode material possesses characteristics such as high ionic and electronic conductivity, strong structural stability, and strong chemical stability. Furthermore, using this composite cathode material in sodium-ion batteries can effectively improve the battery's electrochemical performance.

The invention discloses a high-gain direct-current amplification circuit, and belongs to the field of precision amplification in high-precision direct-current voltage measurement. The problem that the higher the amplification factor of the amplification circuit is, the more difficult the precision is to guarantee is solved. The circuit comprises an input stage circuit, an intermediate stage circuit and an output stage circuit, wherein the intermediate stage circuit comprises a mirror current source and a bias current source; the input stage circuit is used for carrying out primary amplification on an input voltage signal Vi according to a program control proportion signal; the bias current source is used for providing quiescent current for the input stage circuit, and the mirror current source serves as an active load of the input stage circuit; and the output stage circuit is used for carrying out secondary amplification on the voltage signal after the primary amplification. The invention is mainly used for voltage amplification.

The invention discloses a method for manufacturing a polytetrafluoroethylene (PTFE) pole piece by doping onion carbon with iron monatomic, and remarkably improving the electrochemical stability and low-temperature performance of a battery in combination with a specific electrolyte. The preparation method comprises the following specific steps: firstly, pretreating an onion carbon material; treatment is carried out through the modes of iron precursor solution soaking, high-temperature annealing in the argon atmosphere and the like; finally, the monatomic iron is successfully loaded on the onion carbon. The obtained monatomic iron doped onion carbon is prepared into a PTFE pole piece through a PTFE adhesive, so that the electrochemical stability of the pole piece is remarkably improved. And then loading iodine onto the PTFE pole piece in a high-temperature and high-pressure manner. In addition, an electrolyte formed by mixing zinc perchlorate and acetonitrile is also prepared for the lithium ion battery, so that the battery shows excellent cycle stability without capacity fading in 1000 circles and excellent rate capability even in an extremely low-temperature environment of-40 DEG C.

The application discloses a preparation method of a nanoscale multi-metal catalyst, which comprises the following steps: mixing ferric nitrate, magnesium nitrate, lanthanum nitrate, gadolinium nitrate, ammonium heptamolybdate and citric acid with water to obtain a concentrated solution by heating and concentrating; mixing ethylenediaminetetraacetic acid, ammonia water and urea to obtain an ethylenediaminetetraacetic acid solution; mixing the concentrated solution and the ethylenediaminetetraacetic acid solution to obtain a mixed solution by stirring, adding a surfactant into the mixed solution and calcining, and finally roasting. The ferric nitrate, the magnesium nitrate, the lanthanum nitrate and the gadolinium nitrate are mixed, a complexing agent is added, a solution is prepared by using a complexing method, the solution is concentrated, calcined and sieved, and finally the nanoscale multi-metal catalyst is formed. The catalyst prepared by the method has a uniform particle size. The catalyst prepared by the method is combined with a plasma technology to prepare a single-walled carbon nanotube, and the single-walled carbon nanotube (without treatment) has a high ratio, a large IG / ID and a small powder resistance.

The application discloses a ternary positive electrode material, a preparation method, a direct-current internal resistance evaluation method and a battery, and the preparation method of the ternary positive electrode material comprises the following steps: spray granulating a mixture containing a ternary positive electrode precursor and a lithium salt to obtain granular material; and sintering the granular material to obtain the ternary positive electrode material. By sintering the spray granulated granular material, the application is favorable for solving the chain defects such as high residual alkali, poor coating, serious dissolution and the like caused by uneven sintering of the powder material, and realizes the unification of high rate, high capacity, long cycle and excellent storage performance of the ternary positive electrode material in the fast charging scene.

This invention provides a bipolar electrode and a bipolar all-solid-state battery. The bipolar electrode comprises a positive electrode film, a current collector, a bulk material layer, and a carbon material layer. Through the design of the carbonaceous framework and nucleating agent in the bulk material layer, efficient and dense lithium metal deposition is achieved under high voltage conditions. The carbon material layer significantly improves the interfacial contact between the bulk material layer and the all-solid-state electrolyte, reduces interfacial resistance, and improves the deposition and extraction efficiency of lithium metal in the bulk material layer. Furthermore, the carbon material layer provides storage space for lithium metal deposited from the positive electrode, mitigating volume changes during lithium metal deposition in the bulk material layer and improving the stability of the bipolar electrode. The bipolar all-solid-state battery fabricated using the bipolar electrode exhibits high rate capability and long lifespan.

The invention discloses a low-temperature-drift two-stage amplification circuit which comprises a first-stage amplification circuit module, a second-stage amplification circuit module and a summing circuit module. The output end of the primary amplification circuit module is electrically connected with the input end of the secondary amplification circuit module, and the output end of the secondary amplification circuit module is electrically connected with the input end of the summing circuit module; the primary amplification circuit module is used for primarily amplifying an input signal, outputting a first signal and transmitting the first signal to the secondary amplification circuit module; the secondary amplification circuit module further amplifies the received first signal, outputs a second signal and transmits the second signal to the summing circuit module; and the summing circuit module adds a reference voltage to the received second signal, modulates a final output zero voltage and outputs a final output signal. Therefore, perfect combination of high magnification and low temperature drift is realized.

The present invention relates to the field of optical detection, and in particular to a differential interferometric confocal displacement measurement system and a measurement method based on microsphere assistance, wherein the measurement system comprises a laser light source, a test platform, an optical detection structure, a beam splitting structure, a first polarization beam splitting structure, a second polarization beam splitting structure, a detection unit and a signal processing unit; the test platform is used to place a sample, and transparent microspheres are evenly attached to the surface of the sample, and the transparent microspheres are used to increase the magnification of the sample during imaging; the linearly polarized light output by the laser light source is sequentially passed through the optical detection structure, the beam splitting structure, the first polarization beam splitting structure, and the second polarization beam splitting structure to generate four-way interference signals with phases of 0°, 90°, 180°, and 270°, which are received by the detection unit and transmitted to the signal processing unit after photoelectric conversion to calculate the surface height of the sample. The present invention can improve the lateral resolution of the measurement system and enhance the imaging quality through the transparent microspheres attached to the surface of the sample.

The invention belongs to the technical field of new energy, and particularly relates to a coated lithium-rich manganese-based positive electrode material as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, mixing an acrylamide polymer and a metal coating agent, and performing spray drying to obtain a mixture; and S2, coating the surface of the lithium-rich manganese-based positive electrode material with the mixture, and sintering to obtain the coated lithium-rich manganese-based positive electrode material. The coated lithium-rich manganese-based positive electrode material provided by the invention has high capacity, high magnification and high cycle performance.

The invention provides a positive electrode material, a positive electrode plate and a secondary battery. The crystal of the positive electrode material meets the following conditions: the unit cell volume V is less than 102.3, the unit cell parameter a is less than or equal to 2.8790, and the unit cell parameter c is less than or equal to 14.2550; the content of free nitrate ions in the positive electrode material is N1, wherein N1 is more than or equal to 10ppm and less than or equal to 100ppm. By controlling the unit cell volume of the positive electrode material and the content of free nitrate ions in the material to be within the range, the structural stability of the positive electrode material can be improved, and meanwhile, the capacity, the rate and the cycling stability of a battery prepared from the positive electrode material can also be effectively improved.

The invention provides a preparation method of a copper-doped binary manganese-based layered oxide positive electrode material, the positive electrode material and application. A copper salt is used as a dopant, a copper element is doped into a manganese-based oxide by adopting a sol-gel method to obtain a precursor solution, and then the precursor solution is subjected to high-temperature heat treatment to obtain the positive electrode material of the copper-doped binary manganese-based layered oxide. The preparation method comprises the following steps: (1) adding various sylvite, manganese salt, copper salt, a binder and acid into deionized water, and stirring until the materials are completely dissolved to obtain a precursor; and (2) drying the solution obtained in the step (1). And (3) grinding the fluffy solid dried in the step (2) into fine particles. And (4) carrying out high-temperature calcination on fine particles obtained by grinding in the step (3) to obtain copper-doped binary manganese-based layered oxide positive electrode material powder. The method has the characteristics of simple process, low cost and large-scale production, and the positive electrode material as the positive electrode of the potassium ion battery has high specific capacity, good cycling stability and excellent rate capability.

This invention discloses an optical system and a projection device. The optical system has an object side and an image side arranged opposite each other along the optical axis. From the object side to the image side, the optical system sequentially includes a zoom lens assembly and a focusing lens assembly. The zoom lens assembly includes a first lens assembly with negative optical power, an aperture stop, a second lens assembly with positive optical power, and a third lens assembly with positive optical power, arranged sequentially from the object side to the image side. The aperture stop and the second lens assembly are fixed in position relative to the image side. The first lens assembly and the third lens assembly can move closer to each other or further away from each other along the optical axis to enable the optical system to zoom. The focusing lens assembly has positive optical power and can move to a corresponding position along the optical axis to enable the optical system to focus, thus solving the problem of low zoom efficiency in existing optical lenses.

The present application relates to a new type of negative electrode material for lithium ion batteries, and particularly relates to a boron-doped porous carbon gas-phase silicon-carbon composite negative electrode material and a preparation method thereof. The boron-doped porous carbon gas-phase silicon-carbon composite negative electrode material is prepared by mixing a resin with a template agent, doping a boron source, adding a spheroidizing agent and an initiator for spheroidization polymerization, removing impurities and drying, and then performing gas-phase etching to form pores. Silicon is deposited in the pores of the porous carbon and a carbon layer is deposited on the surface of the silicon-carbon precursor by twice chemical vapor deposition, so as to obtain the boron-doped porous carbon gas-phase silicon-carbon composite negative electrode material. The boron element is doped to optimize the electronic conductivity, the spheroidized porous carbon structure is improved to improve the lithium ion transmission channel and enhance the substrate stiffness, and the material has excellent performance of high rate, low expansion and long cycle, so as to solve the problems of insufficient rate performance, low substrate strength and blocked lithium ion transmission of the existing gas-phase silicon-carbon composite negative electrode material in the prior art.

The application discloses a lithium metal negative electrode organic-inorganic hybrid protective layer and a preparation method and lithium metal battery thereof, and belongs to the field of lithium metal batteries. The application adopts a gas-liquid interface self-assembly strategy to make a chloroamide compound and a diisocyanate compound react at high temperature in anhydrous toluene, and obtains a functional polymer by referring to the principle of biological mineralization; the functional polymer is dissolved in an organic solvent after purification to obtain a coating liquid, and an ultrathin, dense and multi-level structure organic-inorganic hybrid protective layer is constructed on the surface of lithium metal through interface self-assembly and solidification into a film. The organic component in the protective layer can densify the interface structure, uniformly guide lithium ion deposition and inhibit dendrites; the inorganic component can regulate the solvation structure of lithium ions, reduce the migration energy barrier and improve the interface transmission kinetics. The protective layer can inhibit the growth of dendrites and significantly improve the cycle and rate performance of the battery. The method has simple process, mild conditions and easy scale production, and provides a practical solution for high-performance lithium metal negative electrodes.

Provided is a telecentric lens system. The lens system includes a front group (T1), a middle group (P), a diaphragm (S), and a rear group (T2). The front group (T1), the middle group (P), the diaphragm (S) and the rear group (T2) are sequentially arranged from an object plane side of the telecentric lens system to an image plane side of the telecentric lens system. The front group (T1) has positive focal power, the rear group (T2) has negative focal power, and the diaphragm (S) is located on an image focal plane of the front group (T1). A focal length of the lens is f, a focal length of the front group (T1) is fT1, a focal length of the rear group (T2) is fT2, and fT1 and fT2 separately satisfy the following relationships with f: 0.80 <|fT1 / f|<1.20, and 3.00 <|fT2 / f|<4.00. The present disclosure provides a telecentric lens system, through the organic combination of optical elements such as the front group, the middle group, the diaphragm, and the rear group, can simultaneously have the advantages of high magnification, high resolution, low distortion, and a large aperture. The telecentric lens system is particularly suitable for the precision detection field and is suitable for large-scale promotion and application.

The application provides a battery pack and an electric device. The battery pack comprises a shell, a battery module and a first gel body. The shell comprises a bottom plate, a first side plate and a second side plate. The battery module is located between the first side plate and the second side plate. The battery module comprises a plurality of battery cells arranged along a third direction. Each battery cell comprises an electrode assembly, a packaging bag and a tab connected to the electrode assembly. The packaging bag has a sealing part. The tab extends from the sealing part to the outside of the packaging bag. There is a first space between the sealing parts of two adjacent battery cells. The first side plate is provided with a first through hole. The first through hole penetrates the first side plate along a first direction. The first through hole is in communication with part of the first space. The first gel body is at least partially arranged in the first space. The first through hole is configured to arrange a first insulating material in the first space to form the first gel body. The first gel body can improve the heat conduction capacity between the battery cells and the shell. The first through hole is also conducive to the ventilation and heat dissipation of the battery pack and conducive to improving the air tightness of the battery pack.