威廉希尔官方下载Feb 12, 2020
The pursuit of energy saving and emission reduction in today's society has been driving the innovation of battery technology, especially the innovation of production technology. Because of its excellent performance, lithium batteries are widely used in the consumer electronics, automotive, and energy markets. Its production technology innovation is particularly important.
The production steps of a lithium battery are a typical "roll-to-roll" process, which requires two processing steps-a film to a single battery, and a single battery assembled into a battery system. A typical lithium battery has three thin films—anode film, separator film, and cathode film—as shown in the following figure.
The thickness of the electrode plating is usually 100 μm, while the separator is 50 μm. The anode film is a graphite plated copper film, the cathode film is a lithium metal oxide plated aluminum film, and the separator is composed of polypropylene and polyethylene. Lithium battery production process:
Due to high requirements for accuracy, controllability and quality of processing machines, foil slitting, foil cutting, tab cleaning and separator foil cutting, etc. The link is more suitable for processing with laser. Compared with traditional mechanical processing, laser processing has the advantages of tool-free wear, flexible cutting shapes, edge quality control, higher accuracy, and lower operating costs.
The metal foil cutting step refers to cutting a roll of metal foil into long and thin strips along the long side according to the design of the battery. Suitable for this link is the infrared pulse laser, which can cut the electrode coating at high speed and high quality. If you have more precise requirements on slit width and quality, you can also consider pulsed green and ultraviolet light.
The metal foil cutting process refers to cutting the slender anode film and cathode film into a desired shape with reference to the design of the battery. Depending on the battery design and whether the metal foil roll is completely coated, you can choose or adjust the beam to cut the plating or only the metal foil. The laser used in this step is the same as the aluminum foil cutting step.
In certain cases, graphite and lithium metal oxides need to be removed to reveal bare copper or aluminum foil labels. The key to this step is to remove the coating material without damaging the metal foil beneath it. Pulsed infrared lasers are best suited for this segment.
Separator foil cutting
Similar to aluminum foil cutting, the cover film must be cut into the required shape according to the battery design. Because the isolation membrane is made of organic compounds, a pulsed UV laser is the most suitable choice.
(Article source: Newport)