18650 lithium battery is better than polymer battery

The so-called polymer lithium battery refers to a lithium battery that uses a polymer as an electrolyte. Specifically, it is divided into two types: semi-polymer and all-polymer. Semi-polymer refers to coating a layer of polymer (usually PVDF) on the barrier film to make the cell's adhesion stronger, the battery can be made harder, and the electrolyte is still a liquid electrolyte. The all-polymer refers to the use of polymer to form a gel network inside the cell, and then inject electrolyte to form an electrolyte. Although the all-polymer battery still uses liquid electrolyte, the amount is much smaller, which greatly improves the safety function of the lithium battery. As far as I know, as long as SONY is mass-producing all-polymer lithium batteries. From another aspect, the polymer battery refers to the use of aluminum-plastic packaging film as the outer packaging of lithium batteries, also commonly known as soft-pack batteries. This kind of packaging film is composed of three layers, namely PP layer, Al layer and nylon layer. Because PP and nylon are polymers, this kind of battery is called polymer battery. 1. The world price of 18650, which is cheaper, is about 1USD/pcs. If calculated according to 2Ah, it is about 3RMB/Ah. The price of polymer lithium batteries is 4RMB/Ah for low-end copycat factories, 5~7RMB/Ah for mid-range, and more than 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. No customization. SONY has always wanted to make lithium batteries the same as alkaline batteries. There are certain industrial specifications, just like AA batteries and AA batteries, which are basically the same all over the world. But because the major advantage of lithium batteries is that they can be designed according to customer needs, and there is no uniform specification. So far, the lithium battery industry basically only needs 18650 standard type, and the others are based on customer needs. For planning. 3. Poor safety. We know that under extreme conditions (such as overcharging, high temperature, etc.), lithium batteries will have violent chemical reactions inside and generate a lot of gas. The 18650 battery uses a metal shell, which has a certain strength. When the internal air pressure reaches a certain amount, the steel shell will be broken and blasted, causing a terrible safety accident. This is why the room where the 18650 battery is detected generally needs to be maintained layer by layer, and no one can enter during the detection. Polymer batteries do not have this problem, even in extreme cases, because the packaging film has low strength, as long as the air pressure is slightly higher, it will break and will not burst. The worst case is incineration. So in terms of safety, polymer batteries are better than 18650 batteries. 4. Low energy density The capacity of a typical 18650 battery can reach about 2200mAh, so that the energy density is about 500Wh/L, while the energy density of polymer batteries can be close to 600Wh/L at this stage. But polymer batteries also have their own shortcomings. First of all, the cost is higher, because it can be planned according to customer needs, and the Ru0026D cost must be included. In addition, the variety of shapes and types have caused various fixtures in the manufacturing process to be non-standard parts, and correspondingly increased costs. The polymer battery itself has poor versatility, which is also brought about by flexible planning. It is often necessary to plan a new one for customers 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: Why is the development of ternary polymer lithium batteries hindered?