6results about How to "Avoid Lithium" patented technology

This invention relates to a low-temperature charging method for lithium-ion batteries. The method includes acquiring constant-capacity data of the battery measured at room temperature, where n1, n2, and n3 represent the charging capacities corresponding to 25–35% SOC, 45–55% SOC, and 75–85% SOC, respectively, and aV, bV, and cV represent the corresponding voltages; preparing for charging at low temperature; charging to aV at a first-rate constant current, recording the capacity m1; determining whether the condition n1 / m1 ≥ 65% is met; if not, maintaining a constant voltage to 0.08–0.12C; if the condition is met, charging to bV at a second-rate constant current, recording the capacity m2; determining whether n2 / m2 ≥ 65% is met; if not, maintaining a constant voltage to 0.03–0.07C; if the condition is met, charging to cV at a rate of 0.33C, recording the capacity m3; determining whether n3 / m3 ≥ 65% is met; if not, maintaining a constant voltage to 0.08–0.12C; if the condition is met, charging at a third-rate constant current. This invention can improve charging capacity and charging efficiency, and improve or prevent lithium plating.

This application provides a battery, a battery pack, and an electrical device. The battery of this application includes a cell pack and a buffer assembly. The buffer assembly is sandwiched between two adjacent cell packs. The cell pack includes a buffer section and a liquid storage section. The liquid storage section can break and release electrolyte when the cell pack reaches its expansion limit. On the one hand, it can provide a certain expansion space for cell expansion, and on the other hand, it can replenish electrolyte, avoid lithium plating due to insufficient electrolyte, and improve battery safety.

The utility model discloses a battery cell and a battery, the battery cell comprises a positive plate, a negative plate and a first protection piece, and the battery cell is formed by winding the positive plate and the negative plate after the positive plate and the negative plate are laminated; the negative plate comprises a first section, a second section and a third section, two ends of the second section are respectively connected to the first section and the third section, two sides of the first section are not provided with negative active material layers, one side of the second section is provided with a negative active material layer, and two sides of the third section are provided with negative active material layers; one end of the first section away from the second section is a winding starting point of the negative plate, and one end of the third section away from the second section is a winding ending point of the negative plate; the first protection piece is connected to the corner area of the second section and covers the end, away from the second section, of the first section. Wherein the first protection piece comprises an elastic layer, and the elastic layer has elasticity. The battery cell provided by the utility model can effectively avoid lithium precipitation.

In order to improve the lithium precipitation problem of a pole piece, the invention provides a battery cell and a battery, the battery cell comprises a positive plate and a negative plate, the positive plate comprises a positive current collector, a positive tab and a positive active material layer, the positive active material layer is arranged on at least one side of the positive current collector, and the positive tab is connected with the positive current collector; the negative plate comprises a negative current collector, a negative tab and a negative active material layer, the negative active material layer is arranged on at least one side of the negative current collector, and the negative tab is connected with the negative current collector; in the length direction of the negative plate, the coating surface density of the negative active material layer is gradually increased along the direction far away from the negative tab; and in any region of the battery cell, the ratio K of the coating surface density of the negative electrode active material layer to the coating surface density of the positive electrode active material layer at the corresponding position is more than or equal to 0.4 and less than or equal to 0.52.

The utility model provides a battery cell and belongs to the technical field of battery structures. The battery cell comprises a lamination body and a reference electrode, the lamination body is formed by stacking positive pole pieces and negative pole pieces in a staggered manner, and the pole pieces at the top and / or the bottom of the lamination body are the positive pole pieces; and the reference electrode is arranged on the outer surface of the positive pole piece on the outermost side of the lamination body. By setting the pole piece at the top and / or the bottom of the lamination body as the positive pole piece and arranging the reference electrode on the outer surface of the positive pole piece, the capacity loss caused by the loss of lithium ions contained in the positive pole piece in the middle area of the lamination body by the reference electrode in the use process can be avoided, namely, the capacity loss is reduced. The battery cell provided by the utility model can stably monitor the potential change of the anode and the cathode in the charge-discharge cycle process of the lithium battery, and the capacity loss rate of the cathode is prevented from being higher than that of the anode, so that lithium precipitation and other safety problems can be avoided.

This invention discloses a composite separator, its preparation method, and its applications, belonging to the field of new energy materials technology. The composite separator provided by this invention includes a substrate layer and a composite coating disposed on at least one surface of the substrate layer; the composite coating includes a two-dimensional amorphous nanoscale filler, comprising a first filler, a second filler, and a third filler; the first filler is boron nitride; the second and third fillers are independently selected from at least one of MoS2, WS2, V2O5, MoSe2, MXene, graphene, and TiS2; and the second and third fillers are different. The composite separator provided by this invention exhibits excellent electrolyte wettability, puncture resistance, heat shrinkage resistance, and mechanical strength. This invention also provides a preparation method and applications of the above-mentioned composite separator.