Abstract: This application provides a positive electrode plate and a preparation method thereof, an electrode assembly, a battery cell, and a battery and pertains to the field of battery technologies. The method for preparing a positive electrode plate includes: providing an adhesive liquid on at least one surface of at least partial to-be-bent position of a positive electrode current collector and curing it to form an adhesive layer, and forming a positive electrode active material layer on at least one surface of the positive electrode current collector having the adhesive layer. The adhesive liquid is first provided on at least one surface of the to-be-bent position of the positive electrode current collector and cured to form the adhesive layer, and then the positive electrode active material layer is formed.

Abstract: An electrode assembly short circuit identification method includes: during charging, according to preset sampling time points, sequentially acquiring a voltage of an electrode assembly at each of the sampling time points; judging whether the electrode assembly has a continuous voltage drop according to the voltage acquired at each of the sampling time points; and determining whether the electrode assembly has a short circuit according to a judgment result.

Abstract: A positive electrode sheet has a straight portion and to-be-bent portions, A thickening layer is disposed on at least one side of a positive electrode current collector of at least some of the to-be-bent portions, the thickening layer is disposed between the positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer covers a surface of the thickening layer is a first positive electrode active material layer, and the positive electrode active material layer located in the straight portion is a second positive electrode active material layer. A ratio of a thickness of the first positive electrode active material layer to a thickness of the second positive electrode active material layer is 20-80%.

Abstract: The present utility model discloses a kinetic energy power bank, comprising a housing, a power generation device, a circuit board, and an energy storage battery. The circuit board is connected to the power generation device. The power generation device has a magnet and a conductive coil disposed therein. In the present utility model, the design of an energy conversion circuit and a layout structure inside the housing is optimized. In this way, the structure of the circuit becomes simpler, costs and electric energy loss are reduced, and the energy conversion rate is higher. Besides, the problem that normal operation of the device is affected due to element interference with each other and thermal energy accumulation is resolved.