The invention belongs to the technical field of
lithium ion batteries, in particular to a method for pre-measuring the volume of a
lithium ion battery. The method comprises the steps of: taking at least two batteries to be formulated, measuring the volumes of the two batteries and calculating the average value Cm of the volumes; after the batteries are formulated and aged, charging the batteries to a preset SOC (stage of charge) and standing still to measure the OCV (open-circuit
voltage); and determining the volume of the batteries according to the OCV and Cm. The method takes the OCV value of the special SOC of the batteries as input, calculates the pre-measuring volume according to a pre-measuring formula, and can be applied to pre-measuring the volume of
lithium ion batteries of different types and volumes, wherein the average pre-measuring error is within 3%, which is smaller than 5% permitted in application of industrial production. The method, on the one hand, solves the problems of long volume test period, large
energy consumption, occupancy of a large number of plants and staffs and high production cost in existing industrial application, and on the other hand, overcomes the deficiencies that the volume test steps are miscellaneous with complex and profound theories in laboratory studies and are not appropriate for industrial application.