Comparison between 18650 lithium battery and polymer battery

The 18650 lithium battery is compared with the polymer battery. The so-called polymer lithium battery refers to a lithium battery that uses a polymer as an electrolyte, which can be divided into two types: semi-polymer and all-polymer. The term semi-polymer refers to the coating of a polymer (usually PVDF) on the barrier film to make the battery tighter, the battery harder, and the electrolyte is still a liquid electrolyte. All-polymer is a polymer that forms a gel network within the cell, and then the electrolyte is injected into the electrolyte. Although all polymer batteries still use liquid electrolytes, they use much less, which greatly improves the safety of lithium batteries. As far as I know, only Sony is currently processing all-polymer lithium batteries on a large scale. On the other hand, polymer batteries refer to the use of aluminum plastic film as the outer packaging of lithium batteries, also known as soft pack batteries. The packaging film is divided into three layers: PP, Al, and nylon. Because polypropylene and nylon are polymers, these cells are called polymer cells. 1. Low price The international price of 18650 is about 1 USD/PCS, and the price of 2Ah is about 3 yuan/Ah. The price of polymer lithium battery is low-end 4 yuan/Ah, mid-end 5-7 yuan/Ah, and mid-end 7 yuan/Ah or more. Like ATL, Lishen, you can sell it for about 10 yuan/piece, but you are not willing to accept a single person. 2. No customization. Sony has been trying to manufacture lithium batteries similar to alkaline batteries. 5 batteries, no. 7 batteries are basically the same all over the world. But one of the advantages of lithium batteries is that they can be shaped according to customer needs, so there is no uniform specification. So far, the lithium battery industry basically only has 18650 specifications, and the rest are planned according to customer requirements. 3. Poor safety. We know that under extreme conditions (such as overcharge, high temperature, etc.) lithium batteries will have violent chemical reactions inside and a large amount of gas attacks. The 18650 battery uses a metal shell with a certain strength. When the internal pressure reaches a certain period of time, the steel shell will burst, and a very terrible safety accident will occur during an attack. This is why the room where the 18650 battery is tested is usually multi-level maintenance and cannot be accessed during the test. Polymer batteries do not have this problem, even in the two poles, because the strength of the packaging is low, as long as the pressure is higher, it will explode instead of exploding. The worst case is incineration. Polymer batteries are safer than 18650 batteries. 4. The general capacity of low energy density 18650 battery can reach about 2200mAh, so the energy density is about 500Wh/L, while the energy density of polymer battery can be close to 600Wh/L. But polymer batteries also have their disadvantages. The first is the high cost, because you can plan according to the customer's needs, and the Ru0026D costs here will be included. Moreover, the appearance is changeable and the variety is wide. As a result, all kinds of fixtures are not standard pieces in the manufacturing process, which also increases the cost accordingly. The polymer battery itself has poor versatility, which is also caused by flexible planning. Often in order to make the difference of 1mm, we have to plan a new one for our customers. 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: Analysis of nine commonly used lithium battery charging processing chips