High-energy-ratio low-internal-resistance cylindrical lithium ion battery

Abstract

The invention discloses a high-energy-ratio low-internal-resistance cylindrical lithium ion battery. The lithium ion battery comprises a cell, wherein the cell comprises a positive plate, a negative plate, an inner diaphragm and an outer diaphragm; the blank foil regions, used as conductive tabs, on the positive plate and the negative plate are positioned at the two ends of the cell respectively; the inner diaphragm, a material-coating region of the negative plate, the outer diaphragm, and a material-coating region of the positive plate are laminated and coiled in sequence to form the cell; and the two ends of the cell are ultrasonically kneaded to form full tabs. According to the high-energy-ratio low-internal-resistance cylindrical lithium ion battery provided by the invention, the positive electrode and the negative electrode take the blank foil regions of the positive plate and the negative plate as the conductive tabs; due to the full tab ultrasonic kneading design, the dense and compacted full tabs which can be subjected to subsequent laser welding conveniently are formed on the electrodes at the two ends of the cell; therefore, the internal resistance of the battery is greatly reduced, and the performance of the battery is improved; due to the coiling way, the efficiency of productivity is taken into consideration as well; and in addition, the lithium ion battery is simple in overall coiled cell design, excellent in electrical performance, high in productivity, and high in practicability.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, in particular to a cylindrical lithium ion battery with high energy ratio and low internal resistance. Background technique [0002] At present, the winding cores of cylindrical lithium-ion batteries are mainly wound-type winding cores with single tabs or multi-tabs and laminated winding cores. Although the winding core with single or multiple tabs has high production efficiency during winding, it has disadvantages in electrical properties such as low energy ratio and high internal resistance due to the limitation of the number of tabs and the area of ​​the core itself; Although the laminated core has the advantages of high energy ratio and low internal resistance, it has problems such as low production efficiency and difficulty in transferring and welding tabs when the number of laminates increases. Therefore, it is necessary to develop a cylindrical lithium-ion battery with high ener...

AI Technical Summary

Problems solved by technology

Although the winding core with single or multiple tabs has high production efficiency during winding, it has disadvantages in electrical properties such as low energy ratio and high internal resistance due to the limitation of the number of tabs and the area of ​​the core itself; Although the laminated core has the advantages of high energy ratio and low internal resistance, it has problems such as low production efficiency and difficulty in transferring and welding tabs when the number of laminates increases.

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