11results about How to "Reduce DC resistance" patented technology

The application discloses a negative pole piece and a lithium ion battery, and relates to the technical field of batteries, and specifically discloses a negative pole piece and a lithium ion battery. The negative pole piece comprises a current collector, a first coating layer and a second coating layer which are stacked on at least one side of the current collector; the first coating layer and the second coating layer each comprise a negative active material, a first binder, a second binder, a first conductive agent and a second conductive agent; and the preparation of the negative pole piece satisfies the following conditions: 2≤C2 / C1≤4 and 1.05≤X / Y≤1.25, wherein C1 and C2 are the mass proportions of the first conductive agent in the first coating layer and the second coating layer respectively, and X and Y are the solid contents of the first coating layer slurry and the second coating layer slurry respectively. According to the application, the solid content of the slurry, the proportions of different active materials and conductive agents are designed and controlled in the double-coating pole piece, and the designed proportions satisfy a certain functional relationship, so that the ion conductivity of the battery can be effectively improved while the high conductivity of the pole piece is maintained, the direct-current internal resistance of the pole piece in the charging and discharging process is reduced, the rate charging and discharging performance is improved, and the lithium precipitation window is widened.

The invention discloses an isolation chip and an isolation system. The isolation chip includes a primary side frame, a secondary side frame, a first die, and a second die. The first tube core is connected with the primary side frame, the second tube core is connected with the secondary side frame, and the primary side frame and the secondary side frame form a three-tap transformer. According to the three-tap transformer, the frame body of the isolation chip serves as the three-tap transformer, the frame body has a larger sectional area, the coil direct-current impedance can be directly reduced, heat loss in the current transmission process is reduced, electromagnetic interference can be restrained through differential transmission of the three-tap isolation coil, and the isolation efficiency is improved.

This invention discloses a multilayer integrated winding method for Litz coils on printed circuit boards, belonging to the field of power electronics technology. The invention includes: providing a PCB with at least four conductive layers; forming input / output cutout areas at the edge of the PCB; dividing multiple parallel conductors constituting one turn of the coil into multiple groups, each group starting from the same layer; each conductor sequentially traversing all conductive layers through vias in a predetermined order, extending circumferentially at a predetermined angle in each layer, so that the current paths of all conductors are uniformly distributed in a direction perpendicular to the coil plane; the input and output ends of all parallel conductors are led out from the cutout areas. This invention increases the number of PCB layers available for a single-turn coil to 4, 6, or more, significantly improving current carrying capacity; the input / output cutouts are concentrated in small-angle areas, reducing the end area occupied; each conductor only needs to undergo a minimum number of position exchanges within the cross-sectional area, reducing wiring complexity and making it suitable for the integrated design of magnetic components.

This invention discloses a method for preparing a high-density patch inductor blank, relating to the field of patch power inductors. In the prefabrication process, the patch inductor blank undergoes a first-stage pressing and a second-stage pressing. During the first-stage pressing, the current positions of the upper die head and the second lower die head are kept constant. The first lower die head is activated and controlled to press upwards at a first preset pressure. When the powder height on the periphery of the cavity is higher than a preset dimension of powder height at the center of the cavity, the second-stage pressing begins. During the second-stage pressing, the first lower die head continues to press at the first preset pressure, while the upper die head and the second lower die head are activated and controlled to press downwards and upwards respectively at a second preset pressure. When the powder height on the periphery of the cavity is equal to the powder height at the center of the cavity, the pressing pressure of the first lower die head is adjusted to the second preset pressure and held, resulting in a patch inductor blank. This method significantly improves the compaction density and permeability of the inductor blank.

This application provides a secondary battery, a battery pack, and an electronic device. The secondary battery includes an electrode assembly. At least one side of the negative electrode current collector of the negative electrode assembly includes an active material layer coated area covered by a negative active material layer and an uncoated active material layer area not covered by the negative active material layer. The direction from the coated active material layer area to the uncoated active material layer area is a first direction. A reinforcing layer covers a portion of the uncoated active material layer area. The uncoated active material layer area includes a tab, and the tab has reinforcing ribs, a portion of which overlaps with the reinforcing layer. The above technical solution of this application can at least prevent wrinkling of the uncoated active material layer area of ​​the negative electrode current collector, improving the support for the tab.

The present disclosure provides a coil electronic component including a support member, a coil disposed on the support member, and a body surrounding the support member and the coil and containing a magnetic material. The coil includes an inner coil and an outer coil sequentially disposed on the support member, where the outer coil is electrically connected to the inner coil. The ratio of the sectional area of each turn of the inner coil to the sectional area of each turn of the outer coil is larger than or equal to 1100 / 1150 and smaller than or equal to 1200 / 1150.

The invention provides a stator of a flat wire motor, which comprises a stator core and a flat wire winding, the number of winding slots of the stator core is 48, the number of poles of the flat wire winding is 8, the number of winding slots of each pole and each phase of the stator core is 2, the number L of layers formed by the flat wire winding in the winding slots is an even number greater than 2, the flat wire winding of each phase comprises four branches, and the branches are parallel to each other. Each branch is wound in the form of a continuous wave winding; the winding of each branch circuit is subjected to continuous cross-layer wire embedding between the first layer and the Lth layer and traverses each pole in the circumferential direction, the interval between the adjacent slots embedded between the radial outermost layer or the radial innermost layer of the winding of each branch circuit is 5, and the intervals between the adjacent slots embedded between the other layers of the winding of each branch circuit are all 6. The winding structure of the stator of the flat wire motor is simple, the end size is small, the resistance of the winding is reduced, the loss of the motor can be reduced, and the operation efficiency of the motor is improved. No welding point exists in the flat wire of each branch, so that the reliability of the winding can be improved.

The application discloses an electrode pole piece and a preparation method thereof, a secondary battery and an electric device. The electrode pole piece comprises a current collector and an active material layer which is compounded on the surface of the current collector. The raw material for preparing the active material layer comprises a sublimation agent, the sublimation agent is composed of water and a sublimation aid, the mass of the sublimation aid accounts for 10-30% of the mass of the sublimation agent, and the sublimation aid is iodine and / or an alcohol with a melting point between-10 DEG C and 10 DEG C. The application can overcome the defect that the above-mentioned sublimation pore-forming process cannot be carried out under conventional conditions, is favorable for reducing energy consumption and cost, saving resources, and has the advantages of being green, environment-friendly and excellent in pore-forming effect.

An inductor component (10) is provided with a green body (11), a first insulating layer (31), a lower layer inductor wiring (51L), and an upper layer inductor wiring (51U). The lower layer inductor wiring (51L) is provided with a lower layer wiring main body (52L) and a lower layer protruding portion (53L) protruding from the outer surface of the lower layer wiring main body (52L) on the third negative direction (Z2) side. The outer surface of the lower layer wiring body (52L) on the third negative direction (Z2) side is in contact with the outer surface of the first insulating layer (31) on the third positive direction (Z1) side. The lower layer protruding portion (53L) is located within a range surrounded by an outer edge of the lower layer wiring main body (52L) and extends along the lower layer wiring main body (52L) when viewed in the third positive direction (Z1). The outer surface of the upper layer inductor wiring (51U) on the third negative direction (Z2) side is in contact with the surface of the lower layer inductor wiring (51L) on the third positive direction (Z1) side.

A copper-iron co-fired inductor and its preparation method are disclosed. The copper-iron co-fired inductor comprises: a square magnetic core, the surface of which is covered with an insulating layer; two flat copper wires, which are arranged parallel to each other on the surface of the magnetic core covered with the insulating layer and adhere to three adjacent faces of the square magnetic core, with the ends of the flat copper wires extending to adhere to a fourth face of the square magnetic core; and a shielding layer, which is adhered to the three surfaces of the square magnetic core with the flat copper wires attached, and is pressed together with the square magnetic core, the insulating layer, and the flat copper wires to form an integrated blank. The blank is then co-fired and sintered to form the copper-iron co-fired inductor. The present invention also provides a method for preparing the copper-iron co-fired inductor. The copper-iron co-fired inductor of the present invention, through the design of the aluminum nitride insulating layer, parallel flat copper wires, and iron-silicon-aluminum shielding layer, greatly improves heat dissipation performance.

Provided is a positive electrode active material with which it is possible to reduce the DC resistance and improve the charge / discharge cycle characteristics of a secondary battery. A positive electrode active material which is characterized by containing a composite material that contains a lithium transition metal composite oxide and a carbonaceous coating film formed on the surface of the lithium transition metal composite oxide, and a metal oxide that contains at least one of W, Mo and Nb, the carbonaceous coating film contains an alkali metal and / or an alkaline earth metal excluding Li.