40results about How to "Avoid thermal runaway" patented technology

This utility model discloses a stacked energy storage device, including a support plate and several energy storage components. Each energy storage component includes an energy storage unit, support legs, and L-shaped limiting plates. The support legs are fixedly installed at the bottom corners of the energy storage units, and the L-shaped limiting plates are fixedly installed at the top corners of the energy storage units. Multiple energy storage units are stacked together, with the support legs of the upper energy storage units inserted into the inner side of the L-shaped limiting plates on the top surface of the lower energy storage units. Multiple limiting frames are fixedly installed on the top surface of the support plate, with the support legs of the lowest energy storage unit inserted into the inner side of the limiting frames. A support plate is fixedly installed on the top surface of the support plate, and multiple insertion holes are provided on the side of the support plate. This utility model allows multiple energy storage units to be stacked together, and the limiting components, in cooperation with the support plate, limit the movement of the energy storage units, preventing them from shifting.

The present application relates to the field of wisdom agriculture and image recognition technology, specifically to a crop disease and pest monitoring system based on image recognition, comprising: an environment perception module, which obtains the environmental context parameters of the monitoring area through multi-modal sensor nodes; a multi-source context analysis module, which constructs a disease and pest outbreak risk model in combination with historical disease and pest distribution spatio-temporal data and calculates the disease and pest risk level; an adaptive strategy generation module, which dynamically reconstructs the image acquisition mode and feature extraction strategy according to the risk level and the edge side resource constraint state, and generates adaptive perception instructions; an image acquisition execution module, which adjusts the physical acquisition parameters and algorithm calculation density of the visual sensor in response to the instructions, and executes image acquisition and recognition; the present application breaks the traditional rigid acquisition mode and realizes the optimal balance between monitoring efficiency and device survival period.

This invention relates to the field of battery technology, specifically to a composite negative electrode current collector, its preparation method, and its application. The composite negative electrode current collector of this invention includes a polymer material layer, a lithium replenishment layer, and a conductive metal layer. The lithium replenishment layer is located on at least one surface of the polymer material layer, and the conductive metal layer is located on the surface of the lithium replenishment layer away from the polymer material layer. The lithium replenishment layer includes a composite lithium material comprising a lithium metal core and a lithium compound coating layer covering the surface of the lithium metal core. The conductive metal layer has multiple through-hole structures. The composite negative electrode current collector of this invention, through the coordination of its various layer structures, is beneficial for improving the storage performance of the negative electrode, reducing battery impedance, shortening the electrolyte wetting time, enhancing lithium replenishment capacity, preventing the formation of lithium dendrites, and improving battery safety performance.

The invention relates to a method (10) for classifying battery cells (1100) of a battery pack (1001) for their cell health. In the method (10), a cell voltage (VZell) and a current (IZell) corresponding thereto are captured for each battery cell (1100) to be classified. An internal resistance (iR) of the respective battery cell (1100) is thus determined. Based on the determined internal resistance (iR), for each battery cell (1100), when the deviation [Delta] iR of the respective internal resistance (iR) relative to the internal resistance reference value (iRW) is within a normal range, it is then classified as healthy. In this case, the internal resistance reference value (iRW) is set to vary over time. The classification of the battery cells (1100) is output in the form of a classification result (KE). The invention also relates to a computer program product, a device (100) and a battery system (1000), each implementing the aforementioned method (10).

The application provides a preparation method of 3,7-dinitro-1,3,5,7-tetraazabicyclononane, comprising the following steps: 1) feeding a first material comprising urea and concentrated sulfuric acid and a second material comprising fuming nitric acid and concentrated sulfuric acid into a microchannel reactor to perform a first-stage nitration reaction, to obtain a first-stage nitration reaction liquid; 2) feeding the first-stage nitration reaction liquid into a first tubular reactor to perform a second-stage nitration reaction, to obtain a second-stage nitration reaction liquid; 3) feeding the second-stage nitration reaction liquid and water into a second tubular reactor to perform a hydrolysis reaction, to obtain a hydrolysis liquid; 4) feeding the hydrolysis liquid and a third material comprising polyoxymethylene and ammonia water into a third tubular reactor to perform a condensation cyclization reaction, to obtain 3,7-dinitro-1,3,5,7-tetraazabicyclononane. The preparation method has the advantages of high safety, less waste pollution and simple operation.

The application provides an electrolyte and a battery comprising the electrolyte, wherein the diazonium salt compound in the electrolyte can be decomposed in advance to generate a large amount of inert gas before a large amount of organic solvent is volatilized to generate gas during a furnace temperature test, and the inert gas is discharged from the pole lug, so that the generated heat is timely released, heat accumulation in the interior is avoided, and heat runaway is avoided; on the other hand, the volatilization of the organic solvent can cause the ion channel in the battery to be closed, so that the side reaction is stopped, the battery can safely pass the furnace temperature test, and the safety of the battery under the condition of heat runaway is significantly improved. Meanwhile, the electron-deficient B element in the diazonium salt compound in the electrolyte has Lewis acidity, can accept an electron pair, can remove HF in the electrolyte, avoids the damage of HF to the interface protection film, and further improves the high-temperature storage performance of the battery.

This invention belongs to the field of lithium metal battery technology, specifically relating to a fluorinated phase-separated polymer ion gel electrolyte, its preparation method and application, and lithium metal batteries. The fluorinated phase-separated polymer ion gel electrolyte provided by this invention comprises a solid phase and a liquid phase; the solid phase is a copolymer of a fluorinated acrylate monomer and a crosslinking agent containing carbon-carbon double bonds; the liquid phase comprises an ionic liquid and a lithium salt dissolved in the ionic liquid. Compared to liquid electrolytes and traditional SPEs, the fluorinated phase-separated polymer ion gel electrolyte provided by this invention has high ionic conductivity, mechanical strength, interfacial stability, and safety. It can effectively suppress the growth of lithium dendrites and adapt to large volume changes, avoiding short circuits and thermal runaway in lithium metal batteries under conditions of overcharging, over-discharging, or mechanical impact.

The invention relates to the technical field of secondary batteries, in particular to a temperature self-adjusting electrode and a secondary battery. The electrode comprises an active material and a composite phase change material, wherein the composite phase change material comprises a first phase change microcapsule and a second phase change microcapsule; wherein the phase change temperature t1 of the first phase change microcapsule is more than or equal to 5 DEG C and less than or equal to 45 DEG C, and the phase change enthalpy Q1 is 100-235J / g; the phase change temperature t2 of the second phase change microcapsule is 20 DEG C lt; t2-t1 < = 155 DEG C, and the phase change enthalpy Q2 meets the following condition: Q2-Q1 < = 200J / g is greater than or equal to 5J / g. According to the electrode provided by the invention, temperature self-adjustment under different working conditions is realized, temperature change is controlled, the service life of the battery under a wide temperature range working condition is prolonged, and meanwhile, thermal runaway of the battery is prevented.

The invention relates to the technical field of fluororubber processing, in particular to a fluororubber sealing element resistant to electrolyte corrosion and a preparation method of the fluororubber sealing element. The fluororubber is prepared from the following raw materials in parts by weight: 100 parts of fluororubber, 10-15 parts of polytetrafluoroethylene micro powder, 4-8 parts of an acid acceptor, 5-7 parts of magnesium-aluminum hydrotalcite, 3-5 parts of polyhedral oligomeric silsesquioxane, 35-40 parts of inorganic filler, 30-35 parts of carbon black, 8-10 parts of an active agent, 2-5 parts of a peroxide vulcanizing agent and 2-5 parts of a cross-linking agent. The fluororubber is composed of low-fluorine-content binary fluororubber and a polyvinylidene fluoride-hexafluoropropylene copolymer, through the synergistic effect of all the components, the volume swelling rate of the sealing element is controlled to be 8% or below under the condition that the sealing element is soaked in an electrolyte at the temperature of 85 DEG C, and the compression set is reduced to be within 15%; and after accelerated aging for 1000 hours, excellent elastic recovery capability and interface sealing pressure are still maintained. The sealing element has the wide temperature range adaptability of-20 DEG C to 200 DEG C and good mechanical strength, and the problem of size instability caused by swelling and softening of traditional fluororubber is effectively solved.

The application discloses a kind of based on inflation plate's spray type liquid cooling battery energy storage cabinet and control method, including energy storage cabinet cabinet and heat management module, the battery pack containing electric core is placed in the energy storage cabinet cabinet inside, spray cooling module, fire-fighting module, control module and energy storage converter module;It also discloses a kind of control method simultaneously, so that electric core works at optimum temperature, guarantees electric core safety, prolongs electric core life;Adopt spray liquid cooling mode, contact thermal resistance is lower, surface temperature uniformity is better;Each module is using module integration design, space structure is compact, installation mode is simple, flexibility is high, adapts to different size energy storage battery pack.

The utility model relates to the technical field of batteries, and discloses a temperature control structure of a lithium battery, which comprises a shell, the top of the shell is fixedly connected with a top cover, the middle of the top cover is fixedly connected with a positive electrode, the bottom of the shell is fixedly connected with a negative electrode, and the inside of the shell is fixedly connected with a metal hollow rod. A roll core is arranged in the shell, cooling fins are fixedly connected to the outer side of the metal hollow rod, a cooling chamber is fixedly connected to the interior of the shell, a cooling pipe is fixedly connected to the interior of the cooling chamber, a dustproof cover is arranged at the top of the cooling chamber, and an opening and closing assembly is arranged in the cooling pipe. The heat dissipation effect is controlled according to the temperature change. According to the utility model, through the cooperation of the radiating fins, the metal hollow rods, the radiating holes, the radiating pipes, the sliding blocks, the radiating grooves, the radiating chambers and other structures, the rapid active heat transfer is realized, the temperature gradient is reduced, the thermal runaway is prevented, and the safety is improved.

The embodiment of the application provides a battery pack and an electric device, which comprise a box body, a plurality of single batteries and a plurality of shielding assemblies; the box body is provided with a plurality of mutually independent containing cavities, the box body comprises a bottom plate and a side plate extending along the circumference of the bottom plate, at least one of the bottom plate and the side plate is provided with a plurality of first through holes, and at least one first through hole is communicated with one containing cavity; at least one single battery is arranged in one containing cavity, the single battery is provided with an explosion-proof valve, the explosion-proof valve is arranged opposite to the first through hole; one shielding assembly is used for covering and sealing one first through hole and is movably connected with the box body, and the shielding assembly is configured to be capable of moving relative to the box body in a direction away from the containing cavity in the case that the explosion-proof valve is actuated, so that the discharge in the containing cavity is discharged. By arranging the shielding assembly, the discharge in the containing cavity can be discharged in time when the explosion-proof valve is actuated, heat loss of other battery units which do not occur heat loss is avoided, and the use safety of the battery pack is improved.

The invention relates to the technical field of lithium ion batteries, and discloses a current collector and a preparation method thereof, an electrode and a lithium ion battery. The current collector comprises a substrate layer, a functional layer and a coating layer, wherein the functional layer is arranged between the substrate layer and the coating layer; the substrate layer is made of an insulating material; the functional layer is of a composite layer structure and comprises metal layers and metal oxide layers which are alternately arranged; and the coating layer is a solid electrolyte layer. The current collector provided by the invention adopts a functional layer structure in which the metal layers and the metal oxide layers are alternated, so that the thermal stability and the safety of the battery under extreme conditions can be improved, and particularly, the current collector has excellent performance in acupuncture, extrusion and short-circuit tests, so that thermal runaway is effectively avoided.

The application relates to a direct-current relay. The direct-current relay comprises a moving spring sheet and an arc striking assembly; the arc striking assembly is arranged on the outer circumferential side of the moving spring sheet and comprises at least one arc striking magnet; wherein the surface of the arc striking magnet facing the moving spring sheet is a curved convex surface. The arc striking assembly can be applied to a scene in which the peripheral magnetic field of the moving spring sheet needs to be increased, can controllably adjust the arc striking strength and effect according to actual application needs, can avoid contact ablation, insulation deterioration, thermal runaway and system-level failure, and can effectively guarantee the safety and reliability of equipment.

The application relates to a diaphragm and an electrochemical device and an electronic device comprising the same, and belongs to the technical field of electrochemical energy storage. The diaphragm comprises a porous substrate and a porous coating on at least one side surface of the porous substrate, and the porous coating comprises fibrous fillers; the fibrous fillers comprise a core layer and a shell layer on the surface of the core layer, the core layer comprises at least one of Mxene and an oxide thereof, MOFs and an oxide thereof, black phosphorus and an oxide thereof, and carbon; the shell layer comprises at least one of silicon dioxide and a lithiumophilic metal oxide; the mass ratio of the shell layer to the core layer of the fibrous fillers is M; the thermal conductivity of the diaphragm is lambda W / (m.K), the specific heat capacity is Cp J / (g.K), and the density is rho g / cm 3 ; the following relationships are satisfied: 0.010 <= (M*lambda) / (2Cp) <= 0.017 and 0.4 <= lambda / (rho*Cp) <= 1.0. The diaphragm can improve the safety performance, cycle life and rate performance of a battery.

The utility model discloses a kind of cooling device and whole package gradient utilization energy storage system, be configured in connecting energy storage box, the inside hollow of energy storage box, cooling device includes: at least one battery tray, at least one cooling component and water tank component, battery tray is connected to the inner wall of energy storage box, the surface of battery tray is formed with first cooling groove, cooling component includes first coil pipe, first coil pipe is embedded in first cooling groove along the orientation of first cooling groove, and abuts at battery pack, water tank component includes water tank and at least one first water pump, water tank is connected to energy storage box, and with the end of first coil pipe is communicated, first water pump is respectively communicated with the inside of water tank and the other end of first coil pipe.The utility model can effectively solve the problem that gradient battery energy storage power station lacks cooling system and cannot regulate or control heat during battery discharging or charging process, leading to security risk in gradient battery energy storage power station.

This application provides a battery charging thermal management control method and a new energy vehicle, relating to the field of vehicle management technology. The method includes: responding to a charging start signal from a target vehicle; acquiring the battery temperature, current state of charge (SOC) parameters, and current ambient temperature of the power battery on the target vehicle; determining a target charging thermal management mode from a set of preset charging thermal management modes based on the battery temperature and the current ambient temperature; determining the current target charging current of the power battery based on the battery's operating temperature range, the current SOC parameters, and the target charging thermal management mode; and during the charging process of the power battery, using the target charging thermal management mode to control the thermal management system of the target vehicle to control the temperature of the power battery, ensuring that the battery temperature remains within the corresponding operating temperature range. This application avoids unnecessary energy loss from the power battery, thereby reducing the overall vehicle charging energy consumption.

This invention provides a battery box and a battery pack. The battery box includes a box body, a plurality of first cooling plates, and a fastening assembly; the box body forms a main chamber; the plurality of first cooling plates are spaced apart in the main chamber to divide the main chamber into a plurality of sub-chambers, the plurality of sub-chambers being configured to accommodate battery modules; the fastening assembly is fixedly connected to the box body; wherein the plurality of first cooling plates are detachably connected to the fastening assembly. This invention aims to solve the technical problem in related technologies where the welded joints of the battery box and cooling plates are prone to deformation, affecting the sealing performance.

This invention belongs to the field of batteries, specifically a high-capacity battery assembly. It overcomes the technical challenges of high cost and heavy weight inherent in existing high-capacity batteries. The assembly includes a pressure-bearing casing and a high-capacity battery and heat exchange device located within the casing. The high-capacity battery comprises a shared pipeline and n individual cells arranged along the x-direction, with their internal cavities connected by the shared pipeline. Each individual cell has a plastic casing with a strength P, where P1 ≤ P ≤ P2. P1 represents the strength requirement of the casing during the formation stage and normal charge / discharge stages, while P2 represents the strength requirement during thermal runaway. The pressure-bearing casing has a vent connected to the shared pipeline. The heat exchange device is located at the top of the high-capacity battery, with the polarity terminals of each individual cell passing through it. Compared to finished battery cells, the individual cells of this invention offer advantages in terms of light weight and low cost.

The utility model relates to the technical field of energy storage equipment, in particular to an energy storage cabinet and an energy storage system. The energy storage cabinet is provided with a cabinet bin, a plurality of battery packs, a control device and a connecting pipeline are arranged in the cabinet bin, the battery packs are stacked in the gravity direction and provided with first connecting ports, the control device is arranged at the top of the cabinet bin in the gravity direction and provided with second connecting ports, and the second connecting ports correspond to the first connecting ports. The connecting pipeline is provided with a plurality of first connecting joints, and the first connecting joints are connected with the first connecting ports in a matched mode. Corresponding to the second connecting port, the connecting pipeline is provided with a second connecting joint, and the second connecting joint is connected with the second connecting port in a matched mode. Wherein the connecting pipeline is used for transporting the flame-retardant medium in the control device into the plurality of battery packs. The energy storage system comprises the energy storage cabinet. The pipeline arrangement mode in the energy storage cabinet and the energy storage system is simple, and the occupied space in the cabinet can be saved.

The utility model relates to the technical field of electrochemical energy storage system protection, in particular to a multi-source information fusion thermal runaway composite detection device which comprises a shell, a cover body is arranged on the upper cover of the shell, a detection cavity is arranged in the shell, and a sound detection assembly is further arranged in the shell outside the detection cavity. One side of the shell is communicated with an air inlet pipe, and the air inlet pipe is communicated with the detection cavity; the sound detection assembly comprises a positioning installation cylinder, a bendable pipe is fixedly installed on the positioning installation cylinder, and a microphone is fixed to the other end of the bendable pipe. The microphone is electrically connected with a signal processing module, and the signal processing module is connected with a controller. According to the utility model, the sound detection assembly, the particle detection assembly, the temperature sensor and the gas sensor are arranged in the device, so that the problem that the safety monitoring and early warning device in the energy storage power station in the prior art cannot detect the chemical reaction of the lithium ion battery in place is solved.

The utility model discloses a new energy battery pack collision protection structure, which belongs to the technical field of new energy batteries, and comprises an assembly seat and an anti-collision plate, the assembly seat is provided with four fixing rings, the upper surface of the anti-collision plate is vertically provided with four vertical rods, the outer surface of each vertical rod is matched with a first spring, and the outer surface of each first spring is matched with a second spring. The outer surface of the top end of the vertical rod is matched with the inner ring of the fixing ring, an arc-shaped energy absorption plate is arranged on the lower surface of the anti-collision plate, and a honeycomb structure is arranged in the arc-shaped energy absorption plate. The problem that it is difficult to effectively buffer and weaken impact force is solved.

The present disclosure provides a sodium-ion battery charging temperature protection circuit, which comprises a first control module, a second control module and a normally closed temperature switch. The control end of the first control module is connected with a charger identification signal end, the first end is connected with the first end of the normally closed temperature switch, and the second end is grounded. The control end of the second control module is connected with the second end of the normally closed temperature switch, the first end is connected with a power supply end, and the second end is connected with a charging output end. The sodium-ion battery charging temperature protection circuit does not rely on an integrated circuit chip for battery protection to achieve temperature protection, and detects the temperature of the sodium-ion battery by using the normally closed temperature switch. When the battery temperature exceeds a safety threshold, the circuit can timely cut off the charging circuit, effectively preventing the sodium-ion battery from appearing thermal runaway phenomenon, improving the safety of the energy storage sodium-ion battery, and avoiding relying on the temperature protection function of the integrated circuit chip, thereby reducing the circuit use cost.

The present invention provides a structure of a battery module, the battery module comprising: a cell stack in which a plurality of pouch-type battery cells are stacked, the plurality of pouch-type battery cells having pouches accommodating electrode assemblies and electrode leads, an electrode lead extending from the electrode assembly and protruding in a length direction to one side of the pouch; and a bus bar assembly disposed on one side of the cell stack in the longitudinal direction and including a bus bar frame having a slit through which the electrode lead passes, and a bus bar disposed on the other side of the cell stack in the longitudinal direction. And a bus bar disposed on one side of the bus bar frame in the length direction and connected to the electrode lead passing through the slit; and a shield member disposed on the other side in the length direction than the bus bar, the shield member including a through hole through which the electrode lead passes, and including a flame retardant material.

The utility model relates to a power supply system for new energy engineering machinery and agricultural machinery accessories, and belongs to the technical field of new energy power supply devices. Comprising a vehicle end direct current charging interface and an accessory end electricity taking plug. The vehicle end direct current charging interface is an original national standard direct current charging interface of new energy engineering machinery / agricultural machinery, the accessory end electricity taking plug is electrically connected with a vehicle high-voltage battery pack through the vehicle end direct current charging interface, and the accessory end is connected to the vehicle end direct current charging interface for electricity taking through a cable with the accessory end electricity taking plug. When the accessory works, electricity taking and vehicle charging share the same electrical interface. Through interface multiplexing and intelligent design, a technical closed loop is formed in the aspects of reducing cost, improving adaptability, enhancing safety, optimizing energy management and the like, and a high-reliability and high-compatibility solution is provided for accessory power supply of new energy engineering machinery / agricultural machinery.

The invention belongs to the technical field of switching power supplies, and discloses a high-precision anti-interference temperature sampling and control circuit which comprises a high-precision stabilized voltage supply, a temperature acquisition circuit, an isolation sampling circuit, a comparison self-locking circuit, a threshold comparison circuit, a protection logic module, a power switch driver and a power switch tube. Input ends of the temperature acquisition circuit and the high-precision stabilized power supply are respectively connected with the power supply; the high-precision voltage-stabilized power supply and the temperature acquisition circuit are connected with the isolation sampling circuit; the isolation sampling circuit is connected with the comparison self-locking circuit; the isolation sampling circuit is connected with the comparison self-locking circuit, the threshold comparison circuit, the protection logic module and the power switch driver; the comparison self-locking circuit is connected with the threshold comparison circuit; the threshold comparison circuit is connected with the protection logic module; the protection logic module is connected with the power switch driver; the output end of the power switch driver is connected with the input end of the power switch tube. According to the invention, the power device can be effectively prevented from continuously heating and degrading during the over-temperature period, and thermal runaway is avoided.

This invention discloses a phase change material composite fiber separator, its preparation method, and its application. The separator's main components are fibers and a phase change material. In this invention, the fibers act as a skeletal support in the separator, exhibiting non-shrinkage at high temperatures and a high porosity. The phase change material in the separator is characterized by a set temperature point; it can absorb a large amount of heat and then undergo a phase change. When a lithium battery malfunctions and the temperature continues to rise to a certain level, the phase change material begins to absorb a large amount of heat, thereby lowering the lithium battery temperature. If the lithium battery cannot cool down after the phase change material absorbs heat, the phase change material will transition from a solid to a liquid state. The gaps between the solid phase change materials will be closed, achieving pore sealing and cutting off the internal ion channels of the lithium battery, thus preventing thermal runaway and providing safety protection.

The application discloses a kind of multistage active and passive protection battery module of lithium ion battery, including lithium ion battery body and metal shell, the inside of the metal shell is equipped with heat control mechanism, the lithium ion battery body is equipped in heat control mechanism inside, the upper end of the lithium ion battery body is equipped with tab, pressure relief valve and fire-retardant agent respectively, the inside bottom of the metal shell is equipped with liquid cooling plate, the lithium ion battery body is equipped in the upper end of liquid cooling plate, the inside upper end of the metal shell is fixedly installed with energy directional pipe, the inside of the energy directional pipe is equipped with fire-resistant pressure-resistant cover plate, the upper end of the fire-resistant pressure-resistant cover plate is equipped with one-way spray valve, the left and right sides of the metal shell are symmetrically equipped with vent opening.This scheme is through fire-retardant agent on the lithium ion battery body and the buffer zone above cooperation, when lithium ion battery body occurs thermal runaway, temperature rises, reaches the melting point of wrapping material, fire-retardant agent is released into buffer space, can effectively inhibit fire.

This invention relates to the field of battery technology, specifically to a separator. The separator includes a base film layer and a polymer coating located on at least one surface of the base film layer. The polymer coating comprises a sponge-like porous structure. A plurality of polymer particles protruding from the surface of the polymer coating are disposed on the side of the polymer coating facing away from the base film layer. The maximum height difference between the plurality of polymer particles is H μm, satisfying 0.2 μm ≤ H μm ≤ 15 μm. The separator of this invention, with its sponge-like porous polymer coating and the uneven polymer particles with height differences on the coating surface, can effectively improve the problem of positive electrode breakage caused by battery expansion.

The application discloses a kind of lithium salt / organic phosphorus compound double-shell coated graphite materials and preparation method.It presents core-shell structure, the core of composite material is artificial graphite, shell is inorganic lithium salt layer and organic phosphorus compound layer in turn from inside to outside.Lithium salt is deposited on the surface of artificial graphite by electrochemical deposition after adding oxidized artificial graphite into inorganic lithium salt, filtration, carbonization, and inorganic lithium salt coated artificial graphite material is obtained;After adding into organic phosphorus salt compound, it is uniformly dispersed, spray drying, and lithium salt / organic phosphorus compound double-shell coated artificial graphite composite material is obtained.The composite material uses inorganic lithium salt coating to reduce material surface defects, can prevent solvent co-embedding, improve the first efficiency of material, prolong cycle life;And outer layer is coated with organic phosphorus compound, when battery appears thermal runaway, impedance increases, prevents thermal runaway, and improves safety performance.