News - The technical problems faced by lithium-ion batteries include

1. The safety of lithium-ion batteries. The hidden dangers of fire, combustion and even explosion of lithium-ion batteries cannot be completely eliminated at present.

2. Lithium-ion batteries need to protect the circuit to prevent the battery from being overcharged and over-discharged.

3. High production requirements and high cost.

What recycling technology does Ni-MH battery have?

Ni-MH battery recycling technology

So far, the technology for the treatment of waste nickel-hydrogen battery batteries mainly includes hydrometallurgy, pyrometallurgy, biometallurgy, and direct regeneration technology of waste nickel-hydrogen batteries. The detailed discussion is as follows in the order of priority.

1. Pyrometallurgy

Pyrometallurgy technology is an ideal method for disposing of waste batteries. It uses the difference in melting point and boiling point of each metal in waste nickel-hydrogen batteries to heat and separate the waste batteries to make the battery Compounds and metals are oxidized, reduced, decomposed and condensed to achieve the purpose of metal recovery. Pyrometallurgical technology can be divided into vacuum metallurgy and atmospheric metallurgy. The former is carried out in a sealed environment, while the latter is carried out in the atmosphere. The pyrometallurgical treatment technology has strong operability and high recovery rate, so it has been widely used.

2. Direct regeneration technology of used nickel-metal hydride batteries

This technology uses concentrated sulfuric acid containing nickel ions to clean the inside of the battery, and recharges the battery while maintaining a certain temperature, so that the hydrophilicity of the separator of the used battery and the capacity of the positive and negative electrodes are effectively restored, and then Realize the regeneration of Ni-MH batteries. Direct regeneration technology has strong operability and high resource recovery rate. However, due to the relatively high requirements for the quality of the raw materials and the relatively high impurity content of the resulting products, the application of this technology has been restricted to a certain extent.

3. Hydrometallurgical technology

This technology uses the characteristics of various compounds and metals in nickel-metal hydride batteries that can be dissolved in acids and solutions to dissolve them to promote the formation of ionic solutions, and use chemical precipitation, replacement, and selective leaching to recover them. A technology for recycling of valuable metals. Hydrometallurgy technology can effectively recover all kinds of metals in nickel-metal hydride batteries, and the purity of the recovered products is also high. However, this method also has certain shortcomings, that is, the technical process is too complicated, and the leaching liquid is relatively corrosive. If the treatment method is improper, it is easy to cause secondary pollution. In addition, the cost of raw material consumption is relatively large, and the economic benefits obtained are not significant. Therefore, the application of this method in the recycling of waste nickel-hydrogen batteries has also shown a trend of decreasing year by year.

4. Biometallurgical technology

Biometallurgical technology is the use of acidophilic microorganisms and their metabolites for direct or indirect use, oxidation, reduction, binding, adsorption or dissolution, and separation and extraction of insoluble components. The principle of this technology is derived from the biological hydrometallurgical technology of the mine property, for which the biological metallurgical method can also be called biological leaching. The advantages and disadvantages of biometallurgical technology are more obvious. Among them, the advantages are simple process flow, convenient operation, and low consumption cost; the disadvantages are that the required leaching time is longer and the leaching rate is not high.

 


Post time: Mar-15-2021