In recent years, the state promotes green travel and strongly supports the production of electric vehicles. Driven by the policy and market environment, the output of domestic electric vehicles is increasing year by year, and the demand for new energy batteries is also increasing. Most of the automotive batteries are lithium batteries. At present, China's lithium battery material enterprises are constantly pouring into the international front line, and some of them have become one of the world's leading enterprises. In the long run, new energy vehicles will become an important industry in China in the next few years. China's material enterprises are expected to accelerate the development speed and usher in global competition opportunities by virtue of the huge domestic market space.
Lithium battery is a kind of battery with lithium metal or lithium alloy as anode material and non-aqueous electrolyte solution. Lithium ion battery has been developed as the main power lithium battery because of its ability to charge repeatedly. Edison was the first scientist to invent lithium battery. Of course, now people are not unfamiliar with power lithium battery, especially after it is widely used in the field of automobile, electric vehicle and other transportation vehicles, people's attention to power lithium battery has been promoted to a higher level.
In the production process of power lithium battery, one link is to bundle and fix the battery shell. In the past few years, the strapping materials were generally steel strips or flame retardant strips. However, due to the characteristics of easy rusting and high cost of steel strips and flame retardant strips, more and more customers came to our company's R & D department in recent two years, hoping that we could make a plan that can not only meet the process requirements but also save costs. Our company leaders also attached great importance to and strongly supported the strapping of power lithium batteries As for the replacement of packaging materials, through many experiments and certification, it is found that PET plastic steel belt with high tensile force can be used to replace steel strip or flame retardant belt.
Due to the excellent physical and mechanical properties of PET plastic steel strip in a wide temperature range, its long-term service temperature can reach 120 ℃, and its electrical insulation is excellent. Even at high temperature and high frequency, its electrical performance is still good, but its corona resistance is poor, creep resistance, fatigue resistance, friction resistance and dimensional stability are very good. It is particularly important to use these characteristics as binding materials for power lithium batteries. Using PET plastic steel belt to bind batteries has the following advantages:
1. The cost is low. The price of ordinary tape is about 1 piece per meter, and that of flame retardant tape is 2-3 pieces;
2. When the module is assembled, the compactness is high, which improves the compactness between the cells and reduces the impact of vibration on the module;
3. Material insulation, no risk of short circuit;
4, high temperature to 130 degrees, good anti-aging performance.
5. Resistance to battery liquid corrosion;
6. The interface strength can reach more than 80% of the belt itself;
7. High efficiency, the average 15-20 seconds to complete a belt binding;
8. The elongation is 12-15%
9. Tensile strain curve
10. The binding technology is mature, standard tools and non-standard automatic equipment are widely used, and the cost is low;