1. Processing of negative electrode materials
(1) First, large-diameter and ultrafine powders must be separated from the required particle size to prevent chemical reactions and improve the safety of the battery cell.
(2) The method of increasing the porosity of the material surface can increase the capacity by more than 10%, and at the same time, the safety performance of the battery can also be improved while the C/A ratio remains unchanged.
2. Control of pulping process
(1) Special chemical reagents are generally used in the pulping process to minimize the tension between the positive and negative electrode slurries. This improves the compatibility between the groups and prevents the materials from agglomerating during the stirring process.
(2) When coating, the gap between the base material and the nozzle should be kept below 0.2mm so that the surface of the electrode plate is smooth and free of defects such as particles, dents, and scratches.
(3) The slurry should be stored for more than 6 hours and ensure that there is no self-aggregation within the slurry. A uniform slurry ensures uniform distribution on the substrates of the positive and negative electrodes of the battery, improving the consistency of the battery cell.
3. Utilizes advanced electrode manufacturing equipment.
(1) Advanced equipment can not only ensure the quality of the electrode sheets, but also greatly improve the uniformity of the electrode sheets of the battery cell, thereby increasing the pass rate of the battery cell.
(2) The density error on a single electrode plate of the coating machine should be controlled within a certain range.
(3) Ensure that the taper runout frequency of the roller press is not greater than 4μm to ensure the consistency of the produced electrode plate thickness. In addition, the equipment should have a good dust collection system to prevent short circuits caused by floating dust.
(4) The slitting machine generally uses a roller cutter, and then performs continuous slitting. This results in a cut without defects such as frizzy edges or burrs.
4. Advanced sealing technology
Currently, domestic lithium-ion batteries generally use laser welding sealing technology. This technology utilizes a YAG rod (yttrium aluminum garnet) laser resonator to emit a beam of light of a single frequency (λ=1.06mm) under intense light excitation. The light is then refracted and focused into a single beam, which is then focused between the cell body and the cover plate, fusing them together to achieve a sealed fusion between the cover plate and the cell body.
