Comparison of the advantages and disadvantages of 18650 lithium battery and polymer battery

18650 lithium battery and polymer battery The so-called polymer lithium battery refers to a lithium battery that uses a polymer as an electrolyte, and is specifically divided into two types: semi-polymer and all-polymer. The term semi-polymer refers to coating a layer of polymer (usually PVDF) on the separator to make the battery harder, the battery harder, and the electrolyte is still a liquid electrolyte. The term all-polymer refers to the use of polymers to form a gel network in cells, and then electrolytes are injected to form electrolytes. 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 composed of three layers: PP layer, Al layer and nylon layer. Since polypropylene and nylon are polymers, these batteries are called polymer batteries. 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. Unable to customize Sony has been trying to manufacture lithium batteries similar to alkaline batteries. 5 batteries, no. 7 batteries are basically the same everywhere in the world. However, one of the important advantages of lithium batteries is that they can be designed according to customer requirements, so it is impossible to have a unified standard. So far, the lithium battery industry basically only has the standard model 18650, and the rest are designed according to customer requirements. 3. Poor safety. We know that under extreme conditions (such as overcharge, high temperature, etc.), a violent chemical reaction occurs inside the lithium battery and a large amount of gas appears. The 18650 battery adopts a metal casing and has a certain strength. When the internal pressure reaches a certain level, the steel shell will burst and explode, causing serious safety accidents. This is why the room where the 18650 battery is tested is usually protected in layers and cannot be accessed during the test. Polymer batteries do not have this problem. Even under the same extreme conditions, due to the low strength of the packaging film, the pressure will only be higher, and there will be no explosion when it ruptures. The worst case is combustion. 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 important thing is the high cost, because it can be designed according to the needs of customers, and the Ru0026D cost must be counted here. Moreover, the shape is changeable and the variety is wide, resulting in various fixtures non-standard parts in the manufacturing process, and correspondingly increased costs. The polymer battery itself has poor versatility, which also brings design flexibility, often in order to make the difference of 1mm to redesign for 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: Knowledge of electrode materials for lithium batteries