Lithium sulphur battery and manufacturing method thereof

Abstract

The invention discloses a lithium sulphur battery taking a lithium intercalated carbon material as a negative electrode in the field of an electrochemical battery and a manufacturing method thereof. The lithium sulphur battery comprises a positive electrode, a negative electrode, electrolyte, a diaphragm and an enclosure and is characterized in that the negative electrode is a lithium intercalated carbon material, rather a normal metal lithium plate. The manufacturing method for the battery comprises the following steps: (1). coating sulfur-containing positive material on an aluminium foil, and coating carbon negative material on a copper foil; (2). winding or stacking the positive electrode, the diaphragm and the negative electrode together, wherein the outermost layer is the negative electrode; (3). separating the outermost carbon negative electrode by the diaphragm, and then winding or stacking with the metal lithium plate pressed on a copper plate; (4). connecting all positive electrodes through electrode lugs, and connecting all negative electrodes with the metal lithium plate through the electrode lugs; and (5). adding lithium-ion electrolyte and keeping the mixture for 10-20 days. According to the lithium sulphur battery and the manufacturing method thereof, lithium is intercalated in the carbon negative electrode by an electrochemical method in advance, so that the condition that high-activity metal lithium appears is avoided during a using process of the traditional lithium sulphur battery, and the safety and cycling performance of the lithium sulphur battery are improved; besides, the manufacturing cost is low, the process is simple, and the application value is great.

Description

Technical field [0001] The invention relates to a lithium-sulfur battery and a preparation method thereof. Specifically, a lithium-intercalated carbon material is used as a negative electrode instead of conventional metallic lithium, and belongs to the technical field of electrochemical applications. Background technique [0002] In recent years, with the development of consumer electronics, energy storage technology, and new energy vehicles, lithium-ion batteries are required to be greatly improved in terms of specific energy and specific power. Lithium-sulfur batteries use elemental sulfur as the positive electrode (theoretical specific capacity is 1675mAh / g) and metallic lithium as the negative electrode (theoretical specific capacity is 3830mAh / g), and the theoretical specific energy of the assembled battery reaches 2600Wh / kg. At the same time, elemental sulfur or containing Sulfur materials have the advantages of a wide range of sources, low prices, and environmental friendl...

AI Technical Summary

Problems solved by technology

Chinese invention patent (CN 101562261A) introduces lithium into a lithium-sulfur battery composed of a sulfur positive electrode and a carbon-based negative electrode by adding a certain amount of lithium-rich material with irreversible delithiation properties to the sulfur-containing positive electrode, and then charges the positive electrode As far as possible, all lithium can be embedded in the carbon-based negative electrode, but the amount of lithium that can be migrated in the lithium-rich material is limited, and the delithiated material still exists in the battery, which will reduce the specific energy of the battery.

Images