Abstract: The present disclosure provides a battery module and a busbar assembly thereof. The busbar assembly comprises a first busbar, a second busbar and a first insulator. The first busbar comprises a first connecting portion connected to a first battery unit, a second connecting portion connected to a second battery unit and a first main portion connecting the first connecting portion and the second connecting portion. The second busbar comprises a third connecting portion connected to a third battery unit, a fourth connecting portion connected to a fourth battery unit and a second main portion connecting the third connecting portion and the fourth connecting portion. The first main portion partially overlaps the second main portion, and the first insulator insulates the second main portion and the first main portion. The first battery unit, the third battery unit, the second battery unit and the fourth battery unit are arranged sequentially.

Abstract: A positive electrode active material and a preparation process thereof, a sodium ion battery (5) and an apparatus containing the sodium ion battery (5) are described, the positive electrode active material satisfying the chemical formula of Na0.67MnxAyBzO2±?, in which A is selected from one or more of Co, Ni and Cr, B is selected from one or more of Mg, Al, Ca, Ti, Cu, Zn and Ba, 0.6<x<1, 0<y<0.1, 0.6<x+y<0.8, z>0, x+y+z=1, 0???0.1, and (I) 3 . 3 ? 3 + 2 ? ( ? - y - z ) 4 < x < 3 . 3 ? 3 + 2 ? ( ? - y - z ) 3 .

Abstract: The present application relates to a lithium ion battery, comprising: a positive electrode plate, a negative electrode plate, a separator disposed between the positive electrode plate and the negative electrode plate, and an electrolytic solution, the positive electrode plate including a positive electrode current collector and a positive electrode active material layer provided on at least one side of the positive electrode current collector, and the electrolytic solution including an organic solvent, a lithium salt and an additive, wherein the lithium salt comprises a primary lithium salt, the primary lithium salt is a first compound in an amount of 30% or more relative to the total molar amount of the lithium salt, and the first compound has a structure represented by the following formula I, and wherein the additive comprises a second compound represented by the following formula II.

Abstract: This application relates to a positive electrode plate and a lithium-ion secondary battery, wherein the positive electrode plate comprises a positive electrode current collector and a positive active material layer disposed on at least one surface of the positive electrode current collector, wherein the positive active material layer comprises a first positive active material Li1+xNiaMebM1?a?bO2?yAy and a second positive active material Li1+zMncZ2?cO4?dBd, and wherein the positive electrode plate satisfies: 0.04?R·P/C?10, wherein R is the resistance of the positive electrode plate, and the unit of R is ?; P is the packing density of the positive electrode plate, and the unit of P is g/cm3; C is the single-side areal density of the positive electrode plate, the unit of C is g/1540.25 mm2. The lithium-ion secondary battery in this application simultaneously has high safety performance, low-temperature kinetic performance, high-temperature cycle performance and high-temperature storage performance.

Abstract: The present disclosure relates to a secondary battery, a battery module, and a device using the secondary battery as a power source. The secondary battery includes a casing and a top cover for connecting with the casing. The casing includes an end portion provided with an opening. The top cover is used to cover the opening of the casing. The top cover includes an inserting portion extending into the casing from the opening. A plurality of notches are provided on an inner side of the end portion of the casing or on a side wall of the inserting portion facing the casing. In the secondary battery, the battery module, and the device using the secondary battery as a power source according to the present disclosure, the secondary battery can reduce the possibility of short circuit occurring in the electrode assembly and improve the operational safety of the secondary battery.

Abstract: The present invention provides a power battery and a positive electrode plate thereof. The positive electrode plate includes a positive current collector and a positive active material layer formed on the positive current collector. The positive active material layer contains a mixture of lithium iron phosphate and FeF3, or a mixture of lithium iron phosphate and LiFe2F6, or a mixture of lithium iron phosphate, FeF3 and LiFe2F6. FeF3 or LiFe2F6 has a high gram capacity of more than 200 mAh/g and has a charge and discharge interval close to that of lithium iron phosphate, which can improve the energy density and the safety performance of the power battery.

Abstract: The present invention relates to an electrode plate, an electrochemical device and a safety coating. The electrode plate comprises a current collector, an electrode active material layer and a safety coating disposed between the current collector and the electrode active material layer, the safety coating layer comprising a fluorinated polyolefin and/or chlorinated polyolefin polymer matrix, a conductive material and an inorganic filler. The electrode plate can quickly open the circuit when the electrochemical device (for example, a capacitor, a primary battery, or a secondary battery) is in a high temperature condition or an internal short circuit occurs, and thus it may improve the high temperature safety performance of the electrochemical device.

Abstract: The disclosure relates to a cap assembly and a secondary battery. The cap assembly includes: a cap plate including a main portion and a convex portion, the main portion including a first surface, a second surface and an electrode lead-out hole; an electrode terminal including an extension portion that extends beyond a hole wall of the electrode lead-out hole and extends in a circumferential direction of the electrode lead-out hole to form a ring structure, and the extension portion is arranged on a side of the first surface away from the second surface; and a sealing ring at least partially disposed between the extension portion and the main portion. The convex portion is disposed on the second surface and around the electrode lead-out hole, and a top surface of the convex portion extends out of the second surface.

Abstract: The present disclosure relates to the technical field of battery, and particularly to a battery module. The battery module includes a case body having a cavity, a plurality of battery units accommodated in the cavity of the case body, an output electrode assembly disposed on the case body and electrically connected to output terminals of the plurality of battery units, and an end cap connected to the case body and arranged to press and cover at least a part of the output electrode assembly. The battery module according to the present disclosure has a sound design, through which the airtightness of the output electrode assembly is not liable to be broken during the running of the vehicle.

Abstract: This application relates to an electrochemical device. The electrochemical device comprises a positive electrode plate, a negative electrode plate and an electrolyte, wherein the positive electrode plate comprises a current collector, a positive electrode active material layer and a safety coating disposed between the current collector and the positive electrode active material layer; the safety coating comprises a polymer matrix, a conductive material and an inorganic filler; wherein based on the total weight of the polymer matrix, the conductive material and the inorganic filler, the polymer matrix is present in a content of from 35 wt % to 75 wt %, the conductive material is present in a content of from 5 wt % to 25 wt %, and the inorganic filler is present in a content of from 10 wt % to 60 wt %; and the electrolyte has a viscosity at normal temperature of ?4 cp.

Abstract: A smoke alarm system comprises a smoke alarm, a temperature detector, a first sampling circuit, a second sampling circuit and an analysis module; a first terminal of the first sampling circuit is connected to the smoke alarm, and a second terminal is connected to a first input terminal of the analysis module; the first sampling circuit is used for sampling from the smoke alarm to obtain a smoke sample value which is then output to the analysis module; a first terminal of the second sampling circuit is connected to the temperature detector, and a second terminal is connected to a second input terminal of the analysis module; the second sampling circuit is used for sampling from the temperature detector to obtain a temperature sample value which is then output to the analysis module; and the analysis module determines whether a smoke alarm signal is generated.

Abstract: A charge and discharge circuit includes: a charging loop, including a battery pack, a first switch module and a charging device connected in series, where, the charging loop is configured to charge the battery pack using the charging device, and precharge the charging device; and a discharging loop, including the battery pack, a second switch module and an electric device connected in series, where, the discharging loop is configured to make the battery pack discharge to the electric device, and precharge the electric device; where, the first switch module and the second switch module each include at least one switch, and a part of switches in the first switch module and the second switch module are semiconductor switches, and the other part of the switches in the first switch module and the second switch module are relays.

Abstract: A power converter as provided includes: a control circuit configured to receive a first electric energy supplied to the control circuit from an energy storage device, receive a second electric energy supplied to the control circuit from a power grid equipment, and be powered on with a third electric energy which is the first electric energy or the second electric energy, and output a control signal; and a power conversion circuit configured to receive the control signal and perform power conversion between the energy storage device and the power grid equipment according to the control signal.

Abstract: The present disclosure provides a secondary battery and a top cover assembly thereof. The top cover assembly includes: a top cover plate and a valve sleeve. The top cover plate includes an accommodation groove and a valve part protruding upward from a bottom wall of the accommodation groove, and the valve part is provided with at least one gas exhaust hole that communicates with an interior of the secondary battery. The valve sleeve is located in the accommodation groove and covers the valve part, a gas exhaust passage that communicates with outside is disposed between the valve sleeve and the valve part, and the gas exhaust passage communicates with the at least one gas exhaust hole.

Abstract: The disclosure relates to a battery lower casing and a battery system. The battery lower casing comprises: a support frame comprising a plurality of fixing beams that are connected end to end to form an accommodating space, wherein each of two fixing beams opposite to each other comprises a fixing portion extending toward the accommodating space, each of the fixing beams comprises fixing tabs at a side of the fixing beam away from the accommodating space, and the battery lower casing is connected to a target object through the fixing tabs; and a bottom plate connected to the fixing beams. The battery lower casing according to the disclosure carries weight of the battery module through the fixing portions of the support frame, and fixes the battery module to the vehicle through the fixing tabs. The bottom plate is only used to isolate the external environment. Therefore, the weight and manufacturing cost of the battery lower casing can be minimized.

Abstract: The present application provides a switch control device and method, a motor controller, and a battery pack heating control system. The switch control device includes: a processing module configured to select, when it is determined that a switch control cycle switches from a previous cycle to a current cycle, a target upper bridge arm switch module for the current cycle from upper bridge arm switch modules other than a target upper bridge arm switch module for the previous cycle and/or select a target lower bridge arm switch module for the current cycle from lower bridge arm switch modules other than a target lower bridge arm switch module for the previous cycle; wherein the processing module is further configured to: during each switch control cycle, control the target upper bridge arm switch module and the target lower bridge arm switch module to be turned on and off.

Abstract: The present application provides a secondary battery, which includes a first electrode assembly, a second electrode assembly, a case, and a top cap assembly. The top cap assembly includes a top cap plate and a first electrode terminal, the top cap plate is connected to the case, and the first electrode terminal is arranged on the top cap plate. The first electrode assembly includes a first body and first tabs extending from the first body, and the first tabs are multiple and stacked. The second electrode assembly includes a second body and second tabs extending from the second body, and the second tabs are multiple and stacked. An end of each of the second tabs that is away from the second body is a second end portion. Each of the first tabs includes a first connecting portion extending beyond the second end portion.

Abstract: A battery pack heating system includes: a main positive switch, a main negative switch, an inverter, an external port, a motor, a control module for auxiliary charging branch, a vehicle control unit, a motor control unit, and a battery management module. The battery management module is configured to send, when an acquired state parameter of the battery pack meets a preset low-temperature-low-power condition, a low-temperature-low-power heating request instruction to the vehicle control unit and the control module respectively. The control module is configured to send a first control signal to control the auxiliary charging branch to be connected. The vehicle control unit is configured to send a second control signal to enable the motor control unit to control on-off of the switch modules in the inverter, and a third control signal to enable the battery management module to control on-off of the main positive switch.

Abstract: The present application discloses a positive electrode plate, a method for preparation thereof, and related lithium-ion secondary battery, electric vehicle and electronic product. The positive electrode plate includes a positive electrode current collector and a positive electrode film disposed on at least one surface of the positive electrode current collector, the positive electrode film includes a positive active material which is a lithium manganese-based positive active material; and wherein the volume resistivity ?sum of the positive electrode plate, the powder volume resistivity ? of the positive active material under a pressure of 20 MPa and the mass percentage a of the positive active material in the positive electrode film satisfy ?sum/?97.5-a?3.

Abstract: The present application provides a welding assembly and a battery module. The welding assembly includes: a first weldment; and a second weldment, welded and fixed with the first weldment to form a welding seam; where, at least one side of the welding seam is provided with an exhaust channel; and the exhaust channel is located between the first weldment and the second weldment. In the present application, an exhaust gas generated during welding can be discharged from the exhaust channel to prevent it from entering the welding seam to reduce the strength of the welding seam.