4846 results about "High current" patented technology

The present invention provides an impedance matching method for an ultrasonic therapeutic apparatus, comprising: obtaining a rated load impedance value of a power amplification module; obtaining an impedance value of a transducer module; determining an expected impedance value to which the impedance matching module should transform the impedance value of the transducer module according to the rated load impedance value; determining the impedance matching module according to the impedance value of the transducer module and the expected impedance value; completing impedance matching of the ultrasonic therapeutic apparatus; performing preliminary impedance matching through a pre-conversion unit composed of multiple transformers of the impedance matching module and completing impedance matching of the ultrasonic therapeutic apparatus through a compensating conversion unit, i.e., an inductor-capacitor impedance, thereby overcoming the problem of using only a single impedance matching network under high power, high current and high frequency conditions, i.e., the inability to match the expected impedance value using only a conversion unit composed of transformers, and the problem of a lack of suitable inductors on the market and large volume of self-made inductors when using only an inductor-capacitor impedance matching network.

The invention relates to the technical field of cylindrical lithium ion battery production, and discloses a method for detecting insufficient welding of a cylindrical lithium ion battery, and the method comprises the following steps: S1, appearance inspection; s2, initial internal resistance benchmark test; s3, applying a short-time large-current pulse to the battery by using a pulse generator, simulating an actual load condition, and recording an instantaneous voltage drop and current response curve of the voltage of the battery end during the pulse period; s4, performing infrared thermal imaging identification and data processing; s5, learning the picture and establishing a model; s6, comparing the test picture and the data with the model; s7, dynamic internal resistance calculation; s8, cold solder joint query and sorting processing; and S9, retesting the electrical performance. According to the invention, the technologies of dynamic internal resistance measurement, nondestructive X-ray or ultrasonic detection, rate discharge test and the like are adopted, so that efficient, accurate and nondestructive detection of the cold solder joint of the cylindrical lithium ion battery is realized, and the production efficiency and the detection precision are remarkably improved.

The invention discloses a power supply circuit, a power supply method, a server, a product and a medium, and relates to the technical field of server power supply, the total power demand of the server is dispersed through the parallel design of multiple power panels, the bus current of a single board connected to a first voltage is reduced to the safe bearing range of an MOS tube, the impact risk is reduced, and the service life of the server is prolonged. The electronic fuse is matched with the single-board power to set an overcurrent protection threshold value, and the short-circuit protection response time is shortened; each board is independently provided with a power supply brick to realize second voltage localization conversion and single board output current reduction, a multi-board output end combined power supply design is combined, a heat source is dispersed to eliminate heat accumulation, the through-current capability is multiplied through a parallel path, and the heat dissipation and electrical design feasibility of the circuit board is improved. The technical problems of MOS tube over-limit, overcurrent protection delay, circuit board heat accumulation and difficult through-flow caused by large current brought by a power supply in a high-power server are solved, and the technical effects of enhancing power supply reliability and optimizing energy efficiency are achieved.

A high current connector includes a base, at least one terminal and at least one insulating piece. The base has an inner wall defining a passage. The terminal is disposed in the passage. The insulating piece is disposed in the passage. The insulating piece is at least partially located between the terminal and the inner wall. A front end of the insulating piece exceeds a front end of the terminal.

The invention discloses an accurate zero crossing point control method for a built-in relay of a large-current electric energy meter, which relates to the technical field of power electronics and intelligent metering and comprises the following steps of: receiving a power grid voltage digital signal, determining a voltage zero crossing point by comparing symbol changes of adjacent sampling values, establishing a phase corresponding relation between voltage and current, and calculating a current phase corresponding relation; generating current zero crossing point prediction data; when a relay switching instruction is received, the specific moment of the next current zero crossing point is calculated, and the control signal sending moment is determined; a relay driving control signal is sent, the actual action completion moment of the relay is collected, the deviation from the expected zero crossing moment is calculated, and the mechanical action delay time parameter of the relay is corrected. By predicting the current zero-crossing time and considering the mechanical action delay characteristic of the relay, accurate switching of the built-in relay at the actual current zero-crossing point is achieved, meanwhile, the self-adaptive adjusting capacity is achieved, the arc energy during large-current switching is reduced, the service life of the relay is prolonged, and the reliability of the electric energy meter is improved.

A method for estimating current-dependent non-linear equivalent circuit model (ECM) parameters of a battery may include measuring a battery voltage across terminals of the battery and a battery current drawn from the battery, modelling behavior of the battery with an impedance model having impedance model parameters, dynamically analyzing the battery current drawn from the battery by a load, dynamically determining safe operating limits for an augmented current for augmenting the current drawn by the load, based on analysis of the battery current and the safe operating limits, determining the augmented current, generating the augmented current to be drawn from the battery, and estimating the impedance model parameters when the augmented current is drawn from the battery.

The invention discloses a multi-physics field simulation method, device and equipment for a large-current connecting piece and a storage medium, and discloses the multi-physics field simulation method for the large-current connecting piece, and the method comprises the steps: carrying out the dynamic simulation of a contact process through a dynamic simulation model of the large-current connecting piece, and determining a dynamic simulation result; and determining a first state geometric model of the large-current connecting piece and a contact pressure function of each contact surface according to a dynamic simulation result, and further performing multi-physics field coupling simulation on the large-current connecting piece in a contact state to obtain a multi-physics field simulation result. According to the mode, when force-electricity-heat multi-physical field joint simulation is carried out on the large-current connector contact element, dynamic simulation is carried out firstly, electrothermal coupling simulation in a contact state is carried out based on a simulation result, and the simulation process is disassembled, so that the convergence and stability of simulation calculation are improved; and reliable information is provided for subsequent design optimization of the large-current connecting piece.

A circuit device includes a current source circuit, a first charging circuit that supplies a first charging current to a charging node, a second charging circuit that supplies a second charging current to the charging node, and a control circuit that sets a current value of the first charging current and the second charging current, based on a current setting value. When the current setting value is in a first range, the first charging circuit supplies the first charging current. When the current setting value is in a second range on a higher current side, the second charging circuit supplies the second charging current. At switching between the first range and the second range, the first charging circuit supplies the first charging current and the second charging circuit supplies the second charging current.

The invention belongs to the technical field of connectors, and discloses a high-voltage large-current connector which comprises a working box and a plug shell, the inner wall of the working box is fixedly connected with a socket shell, the two ends of one side of the inner wall of the socket shell are fixedly connected with high-voltage terminal pieces respectively, the two sides of the outer wall of the socket shell are fixedly connected with protruding rods respectively, and the high-voltage large-current connector further comprises a plug, when the current connecting mechanism is pulled out of the plug shell, firstly, a connecting block is pushed in the direction close to the working box, the connecting block drives a transverse plate and a bent plate to move, and the bent plate drives a movable plate to push and extrude a sliding plate, so that the sliding plate pushes nitrogen in a fixed shell into a conical head gas pipe; nitrogen enters the socket shell and the plug shell through the conical head gas pipe, generation of an electric arc and consumption of electric arc energy are restrained through the chemical stability of the nitrogen, generation of the electric arc can be effectively restrained, when a high-voltage terminal piece is separated from a high-voltage terminal line, the electric arc energy can be rapidly consumed through injection of the nitrogen, and damage of the electric arc to equipment is prevented.

The invention relates to a large current tester for charging pile chip detection, which comprises a base and a cover body, and is characterized in that the top of the base is provided with a positioning mechanism for positioning a chip; a testing mechanism for detecting a chip is mounted at the bottom of the base, the testing mechanism comprises a testing plate and a plurality of probe modules electrically connected with the testing plate, each probe module comprises a heat conduction block, a connecting piece and probe elastic pieces distributed in an array, the connecting piece is sequentially connected with the heat conduction block and the probe elastic pieces in series, and the probe elastic pieces are electrically connected with the testing plate. The probe elastic sheet is arranged on the inner side of the heat conduction block to form a probe module; a pressing assembly for fixing the chip is arranged on the inner side of the cover body, and a control assembly for driving the pressing assembly to be close to the base is arranged at the top of the cover body. During testing, the probe elastic sheets are elastically deformed, stable contact between each probe elastic sheet and the corresponding pin can be guaranteed, the probe elastic sheets are distributed independently, it is guaranteed that the probe elastic sheets have high conduction efficiency in the detection process, and the stability and precision of large-current testing are guaranteed.

The invention relates to the technical field of circuit breakers, in particular to a circuit breaker with a reclosing mechanism, which comprises a shell, a circuit breaker handle is rotationally arranged in the shell, an operating rod and at least three gears meshed in sequence are further rotationally arranged in the shell, and the tooth number of each gear is gradually increased in sequence. The two gears located on the two sides are a small gear and a large gear respectively, the number of teeth of the small gear is smaller than the number of teeth of the large gear, the operating rod is fixedly connected with the small gear, and the large gear is in transmission connection with a circuit breaker handle. Speed reduction and torque increase are realized through the gear train, so that the force required to be applied when a user manually operates the handle of the circuit breaker is remarkably reduced, the operation intensity is reduced, the convenience of manual reclosing is improved, and the manual reclosing device is particularly suitable for a large-current circuit breaker or an occasion requiring a relatively large operation torque.

The present invention discloses a front-terminal vertical wide-tab direct-connected bipolar lead-acid battery and an assembly method thereof. Specifically, a new battery structure is proposed, in which the busbars between the single compartments in a conventional battery are removed, and the connection between the single compartments is replaced by a bipolar plate connection method. The plates and separators are stacked horizontally into a battery slot layer by layer in a specific arrangement order, the tabs are widened, and a row of holes are punched in the middle of the tabs of the bipolar plates. After the lamination is completed, metal rods are inserted into the holes to connect the pole groups and tabs in parallel, the pole groups are locked with a pressing plate, and each monomer is sealed by glue injection. The two halves are then bonded into a whole by glue sealing or heat sealing, and the battery is turned into an upright state. The busbars at the turning points are welded, the terminals are welded, and the side covers are sealed to complete the battery assembly. This structure can greatly improve the high-current and high-rate discharge performance of the battery, and effectively solve the high-rate discharge and assembly problems of lead-acid batteries, providing key support for technological innovation, performance breakthroughs and market expansion of lead-acid batteries.

The present invention provides a mini travel power conversion socket, including: a face cover, a light guide post, a door spring, a main body, and a bottom cover. This invention provides a mini travel power conversion socket equipped with British plugs, European plugs, and American / Australian rotatable adapter plugs; the socket section is designed with a universal socket panel that can accommodate plugs from multiple countries. The product is compact and miniaturized, with a socket safety protection door set in the middle area between the face cover and the main body. It can support AC plugs / sockets capable of carrying 10 A high current. Inside the hardware socket bracket above, there is an integrated L / N pole socket hardware guide plate that is widened and thickened. Below the hardware connection bracket, there is an integrated plug hardware guide plate, along with a positioning block that can independently extend individual plugs.

The invention belongs to the technical field of batteries, and particularly relates to a waste oil mediated preparation method of a whole-domain low-defect pseudographite domain-rich hard carbon material and a method and high-rate sodium ion energy storage. The preparation method comprises the following steps: uniformly mixing and stirring dried biomass and waste grease, putting the mixture into a tubular furnace, heating under protective gas, carrying out high-temperature carbonization, washing with a diluted hydrochloric acid solution and deionized water in sequence, and drying to obtain the waste oil mediated whole-domain low-defect pseudo-graphite domain high-rate hard carbon negative electrode material. According to the waste oil mediated global low-defect and pseudo-graphite domain-enriched high-rate hard carbon negative electrode material obtained by the invention, the structural stability of the material in an ion intercalation / deintercalation process is enhanced, the cycle life of an electrode is effectively prolonged, the high-rate performance of the material can be considered while the platform capacity is ensured, and the service life of the material is prolonged. And it is ensured that the electrode can still maintain high capacity output and good cycling stability under the large-current charging and discharging condition.

The invention discloses a friction nano-generator capable of collecting fluid energy, a preparation method of the friction nano-generator and application of the friction nano-generator in heavy metal ion removal, and belongs to the technical field of nano-generators. The invention discloses a fluid energy collection friction nano-generator. The fluid energy collection friction nano-generator comprises a base, a plurality of supporting plates, stress turbine blades, a rotating shaft, a contact separation assembly and a sliding friction assembly. Through structural innovation and optimization, high voltage is realized by using a contact separation mode, and meanwhile, high current output is realized by considering an independent layer mode. The composite structure design improves the adaptability of the system, so that the system can keep efficient energy conversion in various working environments, and the limitation of unbalanced voltage and current output in the traditional design is overcome. The composite design not only breaks through the power bottleneck of the traditional TENG, but also provides a new idea for efficient energy capture in a more complex mechanical environment. Compared with the prior art, the electric output performance and the device operation are greatly improved.

The invention provides an electric energy meter metering drift compensation method and device, and the method comprises the steps: carrying out the temperature rise test of a voltage sampling resistor and a metering chip of a current sampling element under a large-current heating condition, and collecting the temperature data of each device at different time points; calculating the error contribution degree of a current sampling element, the error contribution degree of a voltage sampling resistor and the error contribution degree of a metering chip according to the temperature data and the temperature coefficient of each unit at different time points; determining a combined error according to a first linear relationship among the error contribution degree of the current sampling element, the error contribution degree of the voltage sampling resistor and the error contribution degree of the metering chip, and performing metering drift compensation on the electric energy meter according to the combined error and the aging compensation parameter; wherein the aging compensation parameter is used for correcting any one of the following effects: resistance value drift, reference voltage attenuation and gain temperature coefficient deterioration. According to the method, the metering drift compensation accuracy of the electric energy meter is improved.

A meter socket adapter (MSA) for connecting a battery energy storage system (BESS) to a household microgrid through a meter combo load center. The MSA includes: a housing matching an electricity meter and a meter socket in the meter combo load center; a plurality of power conductors that connect among the electricity meter, the meter socket, and BESS; a meter interconnection device (MID) switch for connecting a utility grid or one or more distribution energy resource (DER) devices to supply power to household loads in the household microgrid; a MID driving circuit for driving the MID switch to close or open; and a thermal management circuit couple with a plurality of temperature sensors disposed at each high current connection point to prevent overheat.

The invention belongs to the technical field of electromagnetic induction and friction nanometer power generation, and particularly relates to a vibration energy collector based on electromagnetic induction and friction nanometer hybrid power generation. Comprising a friction nanometer power generation unit and an electromagnetic induction unit. The friction nanometer power generation unit comprises an upper insulating support plate, a lower insulating support plate and a friction pair; the friction pair comprises an upper friction assembly and a lower friction assembly, and the upper friction assembly and the lower friction assembly trigger the contact and separation process through external vibration to achieve friction electricity generation. The electromagnetic induction unit comprises a coil, a magnet and a steel body which are sequentially nested, the coil and the magnet are fixedly connected with the upper friction assembly and the lower friction assembly respectively, the steel body is fixedly connected with the lower insulation supporting plate, the magnet and the steel body form a closed magnetic circuit, and the magnet and the coil trigger relative movement through external vibration to achieve electromagnetic power generation. The device is novel in structure and distinct in gradation, integrates a triboelectrification effect and an electromagnetic induction principle, has high-voltage output and high-current characteristics, and can efficiently realize continuous conversion from environment vibration energy to electric energy.

The invention discloses a phase-adjustable large-current generator, and the generator comprises a main circuit module, and a topological structure of the main circuit module employs a multi-stage IGBT inverter; the phase control module inputs a power grid voltage signal through a voltage transformer, adopts an SOGI-PLL structure to improve signal tracking precision, and combines a virtual synchronous machine technology to enhance system balance and a self-adaptive control strategy to dynamically adjust an output signal so as to realize phase control and synchronization; the electromagnetic compatibility optimization module adopts a layered shielding design and is combined with an optical fiber to transmit a control signal, so that the electromagnetic compatibility of equipment is improved; a relay protection test integration module, wherein the relay protection test integration module comprises a differential protection test mode and a distance protection test mode; according to the invention, the problems of low phase adjustment precision, poor synchronization stability and insufficient electromagnetic compatibility of a large current generator in a new energy grid-connected environment are solved.

The invention provides a benzanthracene compound, an intermediate and an organic electroluminescent device, and relates to the technical field of organic electroluminescent materials. The benzanthracene compound provided by the invention can be used as a main body material of a light-emitting layer of an OLED light-emitting device, so that the OLED light-emitting device has relatively low driving voltage, relatively high current efficiency and relatively long service life.

The invention discloses a current detection method and system based on a double-ring TMR nested structure, and belongs to the technical field of current detection. The method comprises the following steps: based on a double-ring TMR system of a double-ring TMR nested structure, performing double-ring detection on the current of a to-be-detected wire in a current measurement scene; synchronously acquiring double-ring data obtained by double-ring detection through AD, and performing wavelet denoising on the double-ring data according to the structure data of the double-ring TMR nested structure; and based on a Kalman filtering algorithm, fusing the double-loop data after wavelet denoising to obtain current information of the to-be-measured wire in the current measurement scene. The method not only has outstanding advantages in the aspects of measurement accuracy and anti-interference performance, but also has a wide measurement range and stable linearity performance, and can be widely applied to complex electromagnetic environments with high requirements on current detection accuracy, such as new energy grid connection, electric vehicle charging piles and intelligent power grids.

The invention discloses a parallel current sharing precision improvement method and system under multiphase heterogenous input. The method comprises the following steps: constructing a current sharing bus signal network; a PI controller is adopted to output a current-sharing adjustment amount VCS to carry out current-sharing loop control, the output amplitude limiting range of the current-sharing loop is set to be 0-+ VCSMAX, and VCSMAX = 2.5% * rated output voltage VOUTNOM; a digital delay compensation technology is added to ensure synchronization of a current-sharing bus network sampling signal and an output current sampling signal; performing moving average filtering on the current-sharing bus network sampling signal and the output current sampling signal after delay compensation by adopting a short-time domain fixed window filtering parameter; a bias error symmetric amplitude limiting mechanism is introduced, a set bias value delta Ihys is subtracted from the original current sharing error, delta Ierrbias = delta Ierr-delta Ihys is used as an effective adjusting signal, and + / -delta Ihys amplitude limiting is applied to delta Ierrbias; an asymmetric integral coefficient adjustment strategy is implemented, when the VCS needs to be increased, a low-speed adjustment coefficient Kup is adopted, when the VCS needs to be reduced, a rapid adjustment coefficient Kdown is adopted, and Kdown is larger than or equal to 2Kup; the steady-state high current sharing precision and the parallel current sharing capability can be realized.

The invention discloses a matrix type resistance output control system and method, and belongs to the field of industrial control, the system comprises a multi-channel resistance output card supporting a plurality of independent channels, each channel is provided with a resistance network, the resistance network comprises a base resistor and a plurality of member resistors which are connected in series, and each member resistor is connected or disconnected through a relay; the measuring module is used for measuring actually measured resistance values of the basic resistor and the member resistor; the calibration module is used for simulating an actual measurement environment to generate calibration coefficients of different channels; the main controller is used for calculating actual target resistance values of different channels according to the calibration coefficient and the actual output resistance values; and the controller is also used for performing traversal calculation according to the actual target resistance value to obtain an optimal relay state combination in different channels, controlling the relay to access the corresponding member resistor, and further controlling the output of the actual output resistance value. According to the invention, 8421BCD coding, input large current measurement and introduction of a calibration coefficient are combined, so that high-precision resistance output requirements in different application scenes are met.

The invention relates to the technical field of power management, in particular to a flywheel energy storage and storage battery hybrid UPS system for a data center, which comprises a load identification module, a disturbance correction module, a scheduling screening module, a time reconstruction module and an instruction updating module. According to the method, the current rotating speed and the output current of the flywheel are obtained, slope change trend analysis is executed, the impact characteristic generated when the load is started can be recognized in advance, and the transient instability risk caused by large-current impact is avoided. And carrying out cross analysis on the original access time sequence of the load and the power disturbance response of the power supply side, so that the load access behavior with concentrated original time sequence and violent current fluctuation is orderly expanded in the time domain. The power supply parameters of the air conditioner group are extracted by the flywheel in the steady-state operation period to serve as the reference, interval adaptation judgment is conducted on the power supply parameters and the operation characteristics of the operation and maintenance equipment to be connected, the equipment with high stability is scheduled preferentially, and the balance and controllability of overall scheduling response are improved.

The invention provides a wide-voltage intelligent control large-current contactor. Comprising a wide voltage control module which is composed of a rectifier bridge, a voltage acquisition module, a single-chip microcomputer control system and a DCDC conversion module and is used for converting input AC / DC voltage into stable 24VDC output; the wide-current control module is used for controlling the coil to start, the contactor can be in a working state even if power failure occurs, the stability of a power grid is ensured, and the device can be applied to the fields of uninterruptible power supply control cabinets, photovoltaic energy storage, power grid distribution and the like.

The invention discloses a large-current inductor based on thermal actuation multidirectional sealing compensation, and particularly relates to the technical field of inductor parts, the large-current inductor comprises an inductor lower cover, an inductor upper cover, two sliding strips and a multidirectional compensation piece, and the inductor upper cover is arranged above the inductor lower cover; the two sliding strips slide on the inner wall of the inductor lower cover; and one side of each sliding strip is provided with a multidirectional compensation piece. Through the multidirectional compensation piece, the multidirectional compensation mechanism obviously enhances the adaptability of the joint of the inductor upper cover and the inductor lower cover to thermal deformation in different directions, so that the sealing compensation capability of the inductor under multidirectional thermal expansion and cold contraction is more excellent, and the sealing durability of the inductor shell is greatly improved; therefore, the problems that the sealing compensation capacity of the inductor is insufficient under multi-directional thermal expansion and cold contraction, and the sealing durability of the inductor shell is poor are solved.

The battery monomer comprises an end cover and an electrode assembly, the end cover comprises a cover plate and a plurality of pole groups arranged on the cover plate, each pole group comprises two poles with opposite polarities, and all the poles are arranged at intervals along the length direction of the cover plate. The electrode assembly comprises a tab end facing the cover plate, and a plurality of tabs are arranged at the tab end in a protruding mode. Wherein each pole is provided with a first flow passing surface and a second flow passing surface which are oppositely arranged in the thickness direction of the cover plate, and each second flow passing surface is connected with one tab. And in the thickness direction, the projection area of the first flow passing surface of each pole is smaller than that of the second flow passing surface. By optimizing the number and the arrangement mode of the pole columns and the pole lugs and optimizing the pole column structure, the charging and discharging efficiency and the heat dissipation capability of the battery monomer are improved, the problem of overhigh local temperature rise is improved, and the reliability of the battery monomer during large current transmission is greatly improved.

The invention relates to a preparation method and application of an electrode, in particular to a preparation method and application of an anti-reverse current self-supporting electrode for anion exchange membrane water electrolysis hydrogen production. The self-supporting (NiCoFe) 9S8 electrode is constructed by adopting a directional solid-phase synthesis strategy to overcome the challenge of performance degradation of the electrolytic cell. The preparation method comprises the following steps: firstly, depositing a precursor solution of FeS2 and CoCl2 on a nickel felt substrate, and then carrying out annealing treatment to obtain uniformly grown (NiCoFe) 9S8; the method not only ensures uniform distribution of multiple metal components, but also constructs firm chemical bonding and efficient charge transfer between the catalyst layer and the conductive substrate through solid-phase interface reaction, and effectively avoids interface impedance caused by introduction of an additional binder. Therefore, high-current-density water electrolysis hydrogen production under intermittent fluctuation power supply is realized. In 1M KOH, the cell voltage is almost not attenuated when the electrode stably operates for 2000h at 500mAcm <-2 >.

The invention relates to a transient enhanced multi-phase Buck converter and a control method thereof, and the method comprises the steps: continuously monitoring and outputting a voltage reduction signal through a capacitance current sampling module, calculating a to-be-judged voltage signal, and outputting a high-level judgment signal when the to-be-judged voltage signal is greater than a reference voltage VTH1; after receiving the signal, the phase control module forcibly outputs logic control signals which are all high levels to the self-adaptive conduction time generation module; the multi-phase current conversion module synchronously conducts all single-phase Buck conversion circuits in the multi-phase current conversion module accordingly, so that the single-phase Buck conversion circuits simultaneously work to output the maximum current, and severe fluctuation of the output voltage is rapidly inhibited; and when the full-phase forced working mode is maintained until the voltage signal to be judged corresponding to the new voltage reduction signal is smaller than the reference voltage VTH2 again, the transient is relieved, and the system is automatically switched back to the conventional minimum current phase interleaving control mode. According to the scheme, the problem of response lag of a traditional multi-phase Buck under extreme load transient can be effectively solved.

The invention discloses a cylindrical battery, a battery pack and electric equipment, the cylindrical battery comprises a battery shell and a battery cell arranged in the battery shell, the battery shell comprises a peripheral shell part and end face shell parts, at least one end face shell part is an electric connection output end, and the end face shell parts are arranged in the peripheral shell part. The thickness of the area where the end face shell part serving as the electric connection output end is electrically connected with the battery cell is a mm, and the area of the end face shell part is s square mm; the battery cell comprises a positive plate with a positive electrode material, the powder conductivity of the positive electrode material is b Siemens per millimeter, and the value range of b / (a * s) is 7.4 e <-14 >-7.5 e <-4 >. The value range of b / (a * s) is controlled within the range of 7.4 e <-14 >-7.5 e <-4 >, it can be guaranteed that the battery has the capacity of charging and discharging in a short time, and it can also be guaranteed that when the heat production amount is increased due to large-current charging and discharging, the safety risk when the battery is used is reduced.