Abstract: The invention provides a lithium-ion battery electrode piece and a lithium-ion battery including the same. The electrode piece includes an electrode active material layer disposed on the surface of the current collector and a protective layer disposed on the surface of the electrode active material layer. The protective layer is composed of metal oxide layers and conductive layers alternately stacked in the horizontal direction. The area ratio of the metal oxide layers to the conductive layers is 4:1-1:4, and the thickness ratio is 0.5:1-1:1. According to the invention, by regulating the shape and ratio of the high temperature stability material and the conductive active material on the electrode piece in the process of coating the protective layer, the amount of the two coating materials is precisely controlled to implement the precise regulation of the high temperature stability and rate performance of the electrode piece.

Abstract: A method for determining a productivity of a coalbed methane well without shutting down the well includes steps of: obtaining coalbed methane basic data; based on PVT experimental data, determining a relationship table between a pressure and a coalbed methane deviation factor, and a relationship table between the pressure and a pseudo-pressure; recording daily gas production rates, bottomhole flow pressures, and cumulative gas productions at each stabilized flow pressure test moment in at least three different production stages; determining formation pressures corresponding to each stabilized flow pressure test moment based on a material balance equation; according to the formation pressures, the bottomhole flow pressures and the production rates, determining coefficients in a deliverability equation of the coalbed methane well for determining the deliverability equation; substituting the formation pressures and the bottomhole flow pressures into the deliverability equation for obtaining corresponding product

Abstract: Embodiments of this application disclose a data protection method and system, a medium, and an electronic device, and belong to the field of communication technologies. In embodiments of this application, a first electronic device establishes a communication connection to a second electronic device. The first electronic device is a trusted device of the second electronic device. When detecting a first trigger condition, the first electronic device sends first data to the second electronic device. The first data is used to trigger the second electronic device to enter a maintenance mode. According to embodiments of this application, the first electronic device triggers the second electronic device to enter the maintenance mode, to protect data of the electronic devices.

Abstract: Techniques are described with regard to managing transaction size during a database replication process. An associated computer-implemented method includes identifying each of at least one transaction associated with at least one source database stored in a replication capture memory, identifying at least one potential excessive memory transaction by applying, via at least one machine learning pattern detection model, pattern detection to each of the at least one transaction stored in the replication capture memory, and constructing at least one compact data unit associated with each of the at least one potential excessive memory transaction. The computer-implemented method further includes facilitating compact data unit transmission to a replication apply server system in order to replicate the at least one compact data unit associated with each of the at least one potential excessive memory transaction to at least one target database via a replication apply server application.

Abstract: An electrical energy storage system is provided in this disclosure, which includes: M battery packs; M first DC/DC converters, where first terminals of the M first DC/DC converters are respectively connected to the M battery packs, the M first DC/DC converters are classified into N first DC/DC converter sets; and N second DC/DC converters, where the N second DC/DC converters one-to-one correspond to the N first DC/DC converter sets, a first terminal of each second DC/DC converter is connected to second terminals of all first DC/DC converters in a first DC/DC converter set corresponding to the second DC/DC converter, a second terminal of each second DC/DC converter is connected to a first interface of the electrical energy storage system, the first interface is to receive a direct current from a power generation system or output a direct current to the power generation system.

Abstract: An electrical energy storage system is provided in this dislosure, which includes: M battery packs; M first DC/DC converters, where first terminals of the M first DC/DC converters are respectively connected to the M battery packs, the M first DC/DC converters are classified into N first DC/DC converter sets; and N second DC/DC converters, where the N second DC/DC converters one-to-one correspond to the N first DC/DC converter sets, a first terminal of each second DC/DC converter is connected to second terminals of all first DC/DC converters in a first DC/DC converter set corresponding to the second DC/DC converter, a second terminal of each second DC/DC converter is connected to a first interface of the electrical energy storage system, the first interface is to receive a direct current from a power generation system or output a direct current to the power generation system.

Abstract: Techniques are described with regard to managing transaction size during a database replication process. An associated computer-implemented method includes identifying each of at least one transaction associated with at least one source database stored in a replication capture memory, identifying at least one potential excessive memory transaction by applying, via at least one machine learning pattern detection model, pattern detection to each of the at least one transaction stored in the replication capture memory, and constructing at least one compact data unit associated with each of the at least one potential excessive memory transaction. The computer-implemented method further includes facilitating compact data unit transmission to a replication apply server system in order to replicate the at least one compact data unit associated with each of the at least one potential excessive memory transaction to at least one target database via a replication apply server application.

Abstract: An electrical energy storage system is provided in this dislosure, which includes: M battery packs; M first DC/DC converters, where first terminals of the M first DC/DC converters are respectively connected to the M battery packs, the M first DC/DC converters are classified into N first DC/DC converter sets; and N second DC/DC converters, where the N second DC/DC converters one-to-one correspond to the N first DC/DC converter sets, a first terminal of each second DC/DC converter is connected to second terminals of all first DC/DC converters in a first DC/DC converter set corresponding to the second DC/DC converter, a second terminal of each second DC/DC converter is connected to a first interface of the electrical energy storage system, the first interface is to receive a direct current from a power generation system or output a direct current to the power generation system.

Abstract: A battery system and a fire extinguishing method for the battery system. The battery system includes a battery management system (BMS) and at least one battery module. The BMS includes a first detection apparatus. The BMS is configured to obtain a risk status of the battery module by using the first detection apparatus, and the BMS is further configured to perform fire extinguishing based on the risk status. Through implementation of the embodiments, safety of the battery system can be improved.

Abstract: Embodiments of this application provide a battery module, to improve consistency of cooling effects of battery cells, so that a battery cell group has a better states of health (SOH). The battery module includes: a heat dissipation mechanical part, which includes a first heat dissipation region and a second heat dissipation region. When an average distance between a heat dissipation pipe in the first heat dissipation region and a cooling medium outflow region is longer than an average distance between a heat dissipation pipe in the second heat dissipation region and the cooling medium outflow region, density of heat dissipation pipes in the first heat dissipation region is greater than density of heat dissipation pipes in the second heat dissipation region.

Abstract: Disclosed herein is a distributed battery pack power supply system, a charging control method, and a discharging control method, where a plurality of battery packs or battery groups is directly coupled in parallel or indirectly coupled in parallel as required using a charging/discharging circuit of the distributed battery pack power supply system and a corresponding control policy. A distributed battery includes a plurality of battery packs, and further includes a controller, a bidirectional voltage transformation circuit, a bypass circuit, a charging circuit, and a charging input end. Each battery pack corresponds to one bypass circuit and one bidirectional voltage transformation circuit.

Abstract: Provided are a chitin whisker-enhanced hyaluronic acid cell scaffold and a preparation method thereof. Components of the cell scaffold include chitin whiskers and cross-linked hyaluronic acid. The chitin whisker-enhanced hyaluronic acid cell scaffold is obtained by dispersing chitin whiskers into deionized water using ultrasound, followed by addition of hyaluronic acid and uniform mixing to obtain an aqueous solution, adjusting a pH value of the aqueous solution to be in a range of 4.0 to 6.0, subjecting the aqueous solution to a cross-linking reaction, dialyzing a reaction product in a phosphate buffer solution, and freeze drying a resulting product. The chitin whisker-enhanced hyaluronic acid cell scaffold and the preparation method thereof can increase a mechanical property and a resistance to degradation of a scaffold material and expand an application scope of hyaluronic acid cell scaffolds.

Abstract: Provided is a gradient injection containing a mixture of polymer microspheres. The injection is a freeze-dried powder composed of a filler, cross-linked sodium hyaluronate microspheres, poly-L-lactic acid (PLLA) microspheres, and an excipient. The powder can be mixed with sterile water and then used for injection cosmetology. A triple gradient effectiveness is provided by mixing the filler, the cross-linked sodium hyaluronate microspheres, and the PLLA microspheres to improve the subcutaneous capacity of human skin and repair skin wrinkles, folds, scars, and aging. The gradient injection is also suitable for repairing large-volume facial fat loss without adverse reactions such as nodules and granulomas.

Abstract: An electric vehicle that includes a battery pack, a direct current socket, and a controller and a charging method for charging between electric vehicles, where in a process in which the direct current socket is coupled to an alternating current socket of another electric vehicle using a charge/discharge cable, the battery pack is controlled based on a charging request of the other electric vehicle to charge the other electric vehicle. Hence, charging between electric vehicles can be conveniently implemented.

Abstract: An insulation resistance detection circuit, detection method, and detection apparatus are provided. The circuit includes an alternating-current signal source, a resonant cavity, a first resistor, a second resistor, a third resistor, a fourth resistor, a first switch, and a second switch. The alternating-current signal source is sequentially connected to the first resistor, the resonant cavity, the first switch, the second resistor, and the third resistor in series to form a loop. The first resistor is connected to a positive electrode of the alternating-current signal source, and the third resistor is connected to a negative electrode of the alternating-current signal source. One end of the second switch is connected to a negative electrode of a to-be-detected battery, the other end of the second switch is connected to the fourth resistor, and the other end of the fourth resistor is connected to ground.

Abstract: A non-contact force type micro-rotating mechanism driven by attractive/repulsive force and a manufacturing method thereof, belongs to the field of intelligent micro devices, and mainly relates to micro electromechanical system technology, precision machining technology, precision assembly and the like. The mechanism adopts the interaction force between magnetic poles to replace the connection mode of a traditional through-hole bearing pressure spring positioning shaft, so that the component part structure of the mechanism can be optimized, and the space utilization rate can be greatly improved. Moreover, the attractive force type structure also has the effect of weakening the radial vibration of the motor, and the coaxiality of the rotor and the stator is improved in the running process of the motor. Meanwhile, the rotating mechanism does not directly output shaft work, a structure can be added on the disc-shaped rotor to realize different functions, an actuator and a control object are integrated.

Abstract: A charging and discharging apparatus includes, in some implementations, an alternating current charging and discharging unit, a bidirectional alternating current/direct current conversion unit, a bidirectional direct current/direct current isolated conversion unit, and a first energy storage unit that are sequentially connected in series, and further including at least one switch unit, a direct current/direct current isolated conversion unit, and a second energy storage unit. A first end of each switch unit is connected to the bidirectional direct current/direct current isolated conversion unit, a second end of each switch unit is connected to a first end of the direct current/direct current isolated conversion unit, and a second end of the direct current/direct current isolated conversion unit is connected to the second energy storage unit.

Abstract: A fast charging method for a parallel battery pack is provided, including: obtaining a maximum charging current allowed by a charging trunk and a charging current required for charging a parallel battery pack; comparing the charging current required for charging the parallel battery pack with the maximum charging current allowed by the charging trunk; if the charging current required for charging the parallel battery pack is less than or equal to the maximum charging current allowed by the charging trunk, performing parallel charging on battery units; or if the charging current required for charging the parallel battery pack is greater than the maximum charging current allowed by the charging trunk, changing some or all of battery units in the parallel battery pack to a series connection, and performing series charging on the battery units. The fast charging method for a parallel battery pack can effectively shorten a charging time.

Abstract: A fast charging method, a fast charging system, and a fast charging apparatus for a series battery pack, where the fast charging method including obtaining charge parameters of battery units in a series battery pack, determining, based on the charge parameters, whether there is a differentiated battery unit in the series battery pack, where the differentiated battery unit is a battery unit whose charge parameter is different from a charge parameter of the rest battery units in the series battery pack, and changing the battery units in the series battery pack to a parallel connection when there is a differentiated battery unit in the series battery pack, and performing parallel charging on the battery units. Hence, the fast charging method for a series battery pack can effectively shorten a charging time.

Abstract: A screen turning-over mechanism includes a rotating shaft connected to a screen and a motor drivably connected to the rotating shaft. The motor is connected to an electromagnetic damping loop which forms a closed path with the motor only when the motor is in a de-energized state. The rotating shaft is also connected to an elastic mechanism. When the motor is energized, the motor drives the rotating shaft to rotate to extend the screen, and the rotating shaft drives the elastic mechanism to deform elastically to store energy; and when the motor is de-energized, the elastic mechanism releases the stored energy to drive the rotating shaft to rotate to retract the screen. The screen turning-over mechanism according to the present application has a simple and compact structure, occupies a small volume of space, and has a long service life.