Due to the high degree of automation, stable stability and high replaceability of the 18650 lithium-ion battery, the 18650 battery has an unparalleled unique advantage in the modularization and standardization of system development. It can effectively reduce production costs and save labor. In addition to the old Tesla, Porsche and domestic Jianghuai, Zotye, Changan, Guangzhou Automobile, etc. have also joined the R & D team of 18650 battery models. According to industry insiders, there will be more models in the future that "fall in love" with the 18650 battery, driving a disruptive change in the way the 18650 battery is used.
However, everything has its two-sidedness, and the pros and cons are the norm. In addition to the above advantages, the 18650 battery can not be ignored. The biggest drawback of the 18650 battery is that its single battery capacity is low, generally around 2~4Ah. Therefore, the number of batteries required for the entire electric vehicle is very large. For example, Tesla vehicles need 7000-8000 18650 batteries. The ground is connected into a module. With so many batteries, battery management is more complicated and consistent.
In many fields such as electric vehicles, the inconsistency of the battery affects the performance of the battery and may even bring some safety hazards.
When lithium-ion batteries are used in series or in parallel in series or in parallel, the safety problems can be basically controlled. However, when lithium-ion batteries are used in large-scale groups, especially when used as electric vehicles, the safety problems will be more prominent. When lithium-ion batteries are used in groups, due to the large number of monomers and complex structure, the uniformity matching and consistency management problems of the monomers are more difficult, which makes the "short board" batteries in the battery pack prone to excessive aging and thus in use. Safety incidents are more likely to occur during the process.
Therefore, in order to solve the safety problem of the lithium ion battery pack, while improving the safety of the battery cell, starting from the perspective of the battery pack system, it is very necessary and urgent to strengthen the lithium ion battery group safety technology.
There are many sources of inconsistency, and the materials that make up the battery itself are not exactly the same, and the process of manufacturing the battery cannot control every battery in any detail. This leads to inconsistent capacity, inconsistent terminal voltages, inconsistent internal resistance, and inconsistent lifetimes. It is difficult to solve it fundamentally. The screening and screening of the front cell is very necessary.
In addition to the electrical properties that need to be screened, the appearance of the 18650 battery also needs to be tested. For example, measuring defects such as scratches, breakages, stains, pits, and bumps on the surface of the battery may affect the assembly of the battery module and the safety characteristics after being assembled.
For example, the damage of the plastic coating on the surface of the battery may cause a safety hazard of short circuit;
Stains, pits/bumps on the end surface, etc., also affect the soldering stability of the circuit;
The flatness of the overmolding also affects the assembly efficiency of the module.
In addition, the length of the cell and the uniformity of the end face diameter will also affect the production efficiency of the module assembly.
Therefore, the appearance inspection is also a necessary link that cannot be ignored before the PACK process.
Satellite broadcasting has the characteristics of wide frequency band, large capacity, stable and reliable performance, wide coverage and suitable for various services. It has become the main means of transmission for radio and television. The performance of satellite ground receiving antenna is directly related to the GH/T value of satellite ground receiving equipment, which determines the viewing quality of satellite broadcasting and TV programs. Therefore, the right choice of satellite receiving antenna is an important premise and guarantee of satellite receiving. Satellite ground receiving station basically chooses two kinds of antenna, namely parabolic antenna (feedforward) and cassegrain antenna (feedback). Parabolic antenna consists of a rotating-symmetric paraboloid, that is, the electromagnetic wave reflection surface and the feed surface, the feed surface in front of the paraboloid
TV antenna Best ,TV Antenna on Amazon,TV Antenna Best buy,TV Antenna Amplifier,TV Antenna at Walmart
Yetnorson Antenna Co., Ltd. , https://www.yetnorson.com