This application relates to the field of
lithium-
ion battery technology, and more particularly to a cylindrical
lithium-
ion battery and its preparation method. The cylindrical
lithium-
ion battery includes a casing, a core disposed within the casing, the core having a central hole, and a central tube disposed within the central hole. The central tube has a hollow structure, with an outer
diameter d and a wall thickness a, satisfying the following relationship: Sc = (d - 2a) / (e / h + f / k), 15 ≤ Sc ≤ 60, where Sc represents the structure-electrochemical
synergy coefficient, d and a are in mm, and e and f represent the areal density of the positive and negative electrodes (mg / cm²), respectively. 2 h and k represent the compaction density (g / cm³) of the positive and negative electrodes, respectively. 3 This application introduces a hollow central tube and synergistically optimizes the geometric parameters of the central tube and the load parameters of the positive and negative electrodes to construct an axial channel at the center of the core that serves both structural support and venting functions. At the same time, it limits the structural electrochemical
synergy coefficient Sc to achieve a balance between
energy density and power characteristics while ensuring cycle life and safety performance.