Soft bag heat sealing process analytical lithium-ion batteries

Source: 2020 - 03 - 28 which hits: analyses the main factors affecting heat sealing, namely, materials, equipment and processes. 1. Material incoming inspection is an important approach to avoid abnormal flow, it is also an important way to reduce the defective rate, reduce the production cost. In the process of packaging, material mainly has two aspects: one is aluminum-plastic film itself, the second is galvanic cell material. Aluminum-plastic film abnormal problems mainly include the aluminum-plastic film itself abnormal problems and impact craters caused by the abnormal problem. Coating itself to ask whether the color is normal, the appearance of the surface whether there is a bubble, stains, scratches, etc. Lu: su other functions of the film itself the corresponding testing data will be provided by suppliers, such as aluminum foil and PP layer of the peel strength, processing function, permeability, etc. Lithium battery enterprises will also carry out corresponding incoming inspection, admit that put into use. Aluminum-plastic film punching pits is to encapsulate the super, beautiful, first introduced the bad CPP pits of punch injury, abnormalities of the pits, which will result in lithium battery injection aluminum-plastic film corrosion, large Angle of stress. Scouring pit is the key to the quality of the project, hole grinding tools, punching hole grinding tools are mainly die, punch, pressure plate and other auxiliary equipment, plan, mould length, width and depth according to the shape of the battery. Then based on the depth of the hole planning of concave and convex mold clearance, according to machining characteristic of aluminum-plastic film planning of concave and convex mold surface roughness. Naked cells into material pollution is the main problem that the surface of the ear, which may constitute a bad packing. 2. Equipment mould planning, structure, planning for packing is very important. In the top sealing process, because of the existence of positive and negative electrode ear makes between the membrane and lu lu/p/g interface is uneven. In PP and PP layer on the surface of the lu/g between to ensure the good bonding and sealing, in nonpolar ear area and ensure that lu/p film layer on the opposite side of the PP has good bonding and sealing. Equipment packaging mould plan and head of choice is more important, when the choice can choose hard seal seal head is difficult to increase the silica gel, silica gel deformation to compensate for the lack of top seal, also can be in hard seal die mould plan, digging ditches for packaging and ear. When choosing soft seal, do not need to consider so much, but be careful of soft sealing packing process, seal, and high temperature resistant adhesive aging. Packing thickness is too big or too small for aluminum packaging plastic film, the thickness is too big is essentially aluminum plastic film packaging is not good, may be due to the small pressure or the equipment abnormal sensor, compressed air pressure is not stable. Packing thickness is too small means poor sealing, may cause the PP melt layer, aluminum layer. The device can be equipped with corresponding limit device, in order to achieve the best effect of packaging. In addition, when the temperature sensor is not normal, it won't reach setting process temperature, lead to seal or owe seal, lead to poor packing. 3. The packaging process is the most key link, the key factors in the process of packaging with temperature, pressure and time. Packaging is the best condition of PP film reaches melting point, bonded together, packaging good appearance without bubble fold, packing high strength, good sealing, after insulation inspection. By tensile testing machine for packaging strength check, the schematic diagram is shown in figure 3. In addition to being able to choose the transverse tensile specimen tensile method and the longitudinal tensile, tensile testing machine with vertical and horizontal tensile testing machine tensile testing machine, vertical machine commonly experimentation is electronic universal testing machine, the sensor in the mobile terminal, so can do vertical zone, stretching and contraction, the sharp degree of the experiment. In terms of stability, specialized level peel strength testing machine is better than that of vertical electronic universal testing machine. Appearance inspection visual check, check after vacuum sealing. Insulation inspection is applied to the ear and aluminum-plastic film in an instant