What are the differences between 18650 lithium battery and polymer lithium battery?

What are the differences between 18650 lithium battery and polymer lithium battery? The 18650 lithium battery is cylindrical, with liquid inside. Because of the battery design and material, the 18650 is suitable for large currents. Therefore, almost all notebooks and electric vehicles are designed with 18650 batteries; only the super notebooks, because of energy saving, can not use 18650 Instead, use polymer lithium batteries for batteries, especially tablet computers; digital cameras can only use 18650 similar batteries because of the high voltage and instantaneous high current required for charging and discharging flashlights, but they are slightly smaller; polymer lithium batteries have the advantage , Small size, large capacity, the disadvantage is that the life is shorter than 18650, because of the use of different designs and materials, some have liquid inside, some are dry or colloidal, and the performance is not as good as the 18650 cylindrical battery when discharged at high current. Therefore, large-capacity and small-volume electrical equipment usually uses polymer lithium batteries, and the most typical performance is mobile phones, tablet computers and other equipment. 1. Lower price The international price of 18650 lithium battery is about 1USD/pcs, which is about 3RMB/Ah if calculated according to 2Ah. The price of polymer lithium battery is 4RMB/Ah for low-end knockoff factories, 5~7RMB/Ah for mid-range, and 7RMB/Ah for mid-to-high end. Like ATL and Lishen, they can generally sell for around 10RMB/Ah, and you are not willing to pick them up when your order is small. 2. Can not be customized SONY has always wanted to make lithium batteries the same as alkaline batteries. There are certain industrial standards, just like No. 5 batteries and No. 7 batteries, which are basically the same all over the world. However, because a major advantage of lithium batteries is that they can be designed according to customer needs, it is impossible to have a unified standard, so now the lithium battery industry basically only has a standard model of 18650, and the others are based on customer needs. Designed. 3. Poor safety. We know that under extreme conditions (such as overcharging, high temperature, etc.), a violent chemical reaction will occur inside the lithium battery, and a large amount of gas will appear. The 18650 lithium battery uses a metal shell with a certain strength. When the internal pressure reaches a certain level, the steel shell will burst and explode, causing a terrible safety accident. This is why the room where the 18650 battery is tested generally must be protected by layers, and no one can enter during the test. Polymer batteries do not have this problem, even in extreme cases, due to the low strength of the packaging film, as long as the air pressure is slightly higher, it will rupture and will not explode. The worst case is burning. Therefore, in terms of safety, polymer lithium batteries are better than 18650 batteries. 4. Low energy density The capacity of a typical 18650 lithium battery can reach about 2200mAh, so that the energy density is about 500Wh/L, while the energy density of polymer lithium batteries is close to 600Wh/L at this stage. But polymer lithium batteries also have their own shortcomings. The important thing is that the cost is high. Since it can be designed according to customer needs, the Ru0026D costs must be included. In addition, the variety of shapes and types have resulted in the non-standard parts of various fixtures in the manufacturing process, and correspondingly increased costs. The versatility of the polymer battery itself is poor, which is also brought about by the flexible design. It is often necessary to design a new one for the customer for the difference of 1mm. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What are the important methods to solve the thermal runaway of power lithium battery?