Can batteries be made from metal, oxygen, and seawater?

Metal-air battery management is a new type of battery that uses more active metals, such as zinc, magnesium, aluminum, etc., as a negative active research material, and develops an air electrode with important catalytic activity that can be used as a positive electrode, plus a suitable electrolyte. .

Metal-air batteries can be divided into zinc-air batteries, magnesium-air batteries and aluminum-air batteries, depending on the metal anode used. The working principle of a metal-air battery is to transfer electrons provided by the active metal of the negative electrode to the positive electrode through an external circuit, and combine with oxygen in the air to form a conductive circuit. The positive electrode of the battery, the air electrode, usually consists of three parts: a gas diffusion layer, which absorbs oxygen from the air and prevents electrolyte leakage; a catalyst layer, which speeds up the rate at which oxygen participates in the reaction and improves the conductivity of the air electrode. The electrolyte in the battery can be alkaline or nearly neutral aqueous electrolyte, or even seawater can be used directly as the electrolyte.

Metal-air batteries have the advantages of high storage capacity, low price and safe use. First of all, the storage capacity of metal-air batteries is extremely high because it consumes oxygen in the air and is inexhaustible. Theoretically, the anode capacity is unlimited. In addition, there is no need to store oxygen in the battery, which makes the theoretical storage capacity of metal-air batteries much larger than commonly used lithium batteries. The theoretical storage capacity is 6-10 times that of lithium-ion batteries, and the actual storage capacity can reach 3 times that of lithium-ion batteries. If it is used as a car power battery, it is expected to achieve a long range of more than 1,000 kilometers.

Secondly, the management cost of metal aerodynamic batteries is low, and the components of the battery system are relatively common and easy to obtain. The consumables used, such as the metal zinc, magnesium and aluminum used for the negative electrode, are all abundant elements in the earth's crust, and the sources can be abundant. The price is relatively low. Finally, the development of metal-air batteries is safer for the country. Since it uses aqueous electrolytes, it has no flammable or explosive components and there is no risk of burning or explosion.

According to the different charging characteristics of the negative electrode, metal-air batteries can be divided into secondary batteries (zinc-air batteries) and primary batteries (magnesium-air batteries and aluminum-air batteries). They have a simple structure, are easy to operate, and do not require dedicated maintenance. No harmful substances are released during the recycling process, and it is also known as "green energy for the 21st century."

Metal-air batteries have broad application prospects in many fields. For example, metal-air batteries have the advantages of ease of use and high safety, and can power small electrical equipment such as hearing aids. Currently, small zinc-air batteries have been designed as button batteries and are widely used in batteries for hearing aids. The aluminum-air battery among metal-air batteries has the characteristics of high storage capacity and long battery life. It can be an ideal energy supply choice for electric vehicles, drones, and portable devices. Moreover, the aluminum-air battery only needs to replace the negative metal plate and does not require charging. , improving charging efficiency and convenience. Combining metal-air batteries with lithium-ion batteries can combine the advantages of high storage capacity and long battery life, and the battery life can be 2 to 3 times that of lithium-ion devices. Magnesium air batteries and aluminum air batteries can be used as emergency power supplies for power supply in natural disasters or outdoor activities. They have a simple structure and are easy to operate. They can provide reliable power supply only by adding water at critical moments. 2 kg The left and right metal-air batteries can meet the emergency power needs of a family of three, and do not produce noise or harmful substances. They are a green and safe source of electricity. For areas with complex terrain or remote islands and reefs, metal-air batteries are used to provide power, which has low technical difficulty and high safety.