▎ 摘　　要

NOVELTY - Supplementing lithium comprises (i) using a half-cell to test the anode material and the cathode active material, determining the first charging gram capacity Q positive of the anode active material, (ii) according to the preset N/P value, determining the first proportional relationship between the mass m of the cathode active material required for making the battery and the mass m of the anode active material; where, N/P is as given in the specification, (iii) calculating the second proportional relationship between the quality m of the lithium-supplementing agent in the battery and the positive m, where the second proportional relationship satisfies as given in the specification, and (iv) based on the second proportional relationship and the m, determining the value range of the m supplement, and adding lithium supplement agent whose mass is within the value range during the production process of the anode pole piece. USE - Method for supplementing lithium used in preparing battery (claimed). ADVANTAGE - The method enables adding the lithium supplementing agent whose mass is in the value range during the manufacturing process of the anode pole piece, so the need to repeatedly test for many times can be avoided. The operation of the method is simple, practical and efficient, and can quickly calculate according to the requirement to obtain the mass range of lithium supplement agent. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: a method for preparing battery; and a battery. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of the functional flow of the lithium supplementation method (Drawing includes non-English language text).