Zinc-coated carbon is a cell type of carbon-zinc cell invented since 1866 by Georges Leclanch, a French engineer. This type of cell is suitable for electronic devices that require less power to operate, such as alarm clocks, flashlights, TV remote controllers, etc.
The name carbon-zinc cell indicates the basic elements of this cell type including carbon rods act as a conductor from the cathode which is manganese dioxide, mixed with activated carbon. The anode is the zinc case, in addition to acting as an anode, it is also used to contain cathode substance. There is a layer of ammonium chloride and zinc chloride solutions act as an electrolyte between the cathode and the anode layers. The chemical reaction of the battery will continue until the manganese dioxide reacts completely meaning the battery is running out of electricity which users should remove the batteries from the electrical equipment because the electrolyte solution that is still in the battery is acidic. Therefore, the substance can continue to react with zinc case and causing internal chemicals to leak and damage electrical equipment.
The highlight of this carbon-zinc cell type is it is cheap and has many sizes to choose from. At the same time, it has a weakness which is it generates the least energy when compared to other types of battery. In addition, if stored in a place that is too hot or cold, the efficiency of the cell will decrease.
Now let's see how to properly use batteries. Starting from changing all the batteries together at the same time, you should not mix used batteries with the new one. You should always switch off the device after using, do not leave it unnecessarily on. You should not mix many types of batteries or many brands to together. You should also remove batteries from the device every time after use. When putting new batteries, you should check that the batteries and terminals are placed correctly. And the main prohibitions are not to remove the batteries for no reason and not place them under high temperature condition to avoid shortening the battery life. And finally, you should not recharge the non-rechargeable battery since it is potentially harmful.
From the study “Is the used battery dangerous?” By Thailand’s HSM, there are many types of batteries used in daily life. But the dangerous one is the rechargeable battery which contains dangerous substances such as nickel, cadmium, and lithium. If looking at the label, it will display by abbreviation as NiCd, NiMH, Li-ion and Li-ion polymer. Batteries that are not hazardous are alkaline and carbon-zinc batteries which contain manganese and zinc. These two substances are considered a low toxicity. The question is whether the acidic water comes from the used alkaline or carbon-zinc batteries is dangerous? The greasy water comes from the chemical reaction in the battery. The heat generated will cause water vapor which will be absorbed by the activated carbon that has an electrically conductive gel. When the steam condenses into water droplets, it will cause the conductor to become an electrical solution called electrolyte solution. The alkaline battery has an alkaline electrolyte solution that is concentrated in the form of potassium hydroxide, which is absorbed by the carbon fiber sheet in batteries stopping the electrolyte solution from flowing out. But sometimes we may see some stains or white salt crystals. The carbon-zinc battery has a weak base alkaline solution such as ammonium chloride and zinc chloride. But since the carbon-zinc battery has a galvanized sheet covered with another layer of plastic sheet, this makes the electrolyte solution able to flow out easily. Therefore, when removing batteries, you should wear gloves and masks to prevent potential hazards.