Introduction to dry battery.




Dry cell is a chemical battery that uses paste electrolyte to generate direct current (wet battery is a chemical battery that uses liquid electrolyte). It is roughly divided into primary and secondary batteries. They are part of daily life. The middle is generally used, as well as a lightweight battery. They can be used on many electrical appliances.

Common dry batteries are zinc-manganese batteries (or carbon-zinc batteries, or dry Leclanché cell).

Dry batteries are primary batteries in chemical power sources and are a kind of disposable batteries. Because the electrolyte of this kind of chemical power supply device is a kind of non-flowable paste, it is called a dry battery, which is relative to a battery with a flowable electrolyte. Dry batteries are not only suitable for flashlights, semiconductor radios, tape recorders, cameras, electronic clocks, toys, etc., but also for various fields in the national economy such as national defense, scientific research, telecommunications, navigation, aviation, and medicine. 

Ordinary dry batteries are mostly manganese-zinc batteries, with a positive carbon rod in the middle, a mixture of graphite and manganese dioxide, and a layer of fiber mesh. The mesh is coated with a thick electrolyte paste, which is composed of ammonium chloride solution and starch. There is also a small amount of preservative. 

The outermost layer is a cylinder made of metal zinc skin, which is the negative electrode. The discharge of the battery is the electrolytic reaction of ammonium chloride and zinc, and the released charge is conducted by graphite to the positive carbon rod. The electrolytic reaction of zinc is It will release hydrogen. This gas will increase the internal resistance of the battery. 

The manganese dioxide mixed with graphite is used to absorb hydrogen. However, if the battery continues to work or is used for too long, the manganese dioxide will be too late or too late. It is nearly saturated and unable to absorb any more. At this time, the battery will lose its function due to too much internal resistance and too small output current. However, if the battery is heated or left for a period of time, the accumulated hydrogen gas inside it will be heated and released. Slowly release. Manganese dioxide has also been reduced and recovered, and the battery will be vigorous again!


The chemical equation is: Zn+2MnO2+2NH4Cl= ZnCl2+Mn2O3+2NH3+H2O

Do not dissect dry batteries! ! Do not put it on the fire for burning or roasting. 

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