High-dispersity nanocrystalline manganese dioxide electrolysis additive as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of electrolytic manganese dioxide, and provides a high-dispersity nanocrystalline manganese dioxide electrolytic additive and a preparation method and application thereof. The method comprises the steps of: adding manganese dioxide powder, water and an active dispersing agent into a container according to a certain proportion, raising the temperature to 40-60 DEG C under stirring, and performing heat preservation to obtain a slurry dispersion; transferring the slurry dispersion to a bead mill for milling until the part with the particle size of 50-150 nm of the slurry dispersion reaches more than 50%, then separating the mixture by a centrifugal machine, and transferring the light liquid obtained by separation to a transfer container; and adding polyvinyl pyrrolidone into the transfer container, and uniformly stirring and dispersing to obtain the high-dispersity nanocrystalline manganese dioxide electrolysis additive. By adding two active dispersants before and after bead milling, the additive which is free of agglomeration and precipitation and good in dispersity and uniformity is prepared; the additive does not need to be prepared and used immediately during production and does not need to be stirred for a long time, so that production can be flexibly arranged, and power consumption is saved.

Description

technical field [0001] The invention relates to the technical field of electrolytic manganese dioxide, in particular to a highly dispersed nanocrystalline manganese dioxide electrolytic additive and a preparation method and application thereof. Background technique [0002] With the continuous development of the battery industry, especially the popularization of electric bicycles and power vehicles, the manganese dioxide dedicated to new battery positive electrode materials such as zinc-manganese batteries, alkaline batteries, and lithium manganate batteries has developed rapidly. Common manganese dioxide can be divided into three categories: natural manganese dioxide (NMD), electrolytic manganese dioxide (EMD) and chemical manganese dioxide (CMD). Replaced by electrolytic manganese dioxide, the demand for electrolytic manganese dioxide is increasing year by year, and the product quality requirements for electrolytic manganese dioxide are also getting higher and higher. [...

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Problems solved by technology

[0003] In order to increase the output of electrolytic manganese dioxide products with the minimum investment without increasing the production line, realize the target of increasing production, and control various indicators such as cost and quality, the applicant has developed a nanocrystalline microsphere modified electrode to produce electrolytic manganese dioxide. The method, the self-developed bead mill system, adopts the nano-bead mill without screen design, which solves the technology that the bead mill system cannot meet the requirements of powder milling particle size reaching nanometer level, and cannot be continuously fed and produced, and the output is low question

However, using this technology, although the particles of nanocrystalline microspheres can reach the nanoscale during bead milling, the finer the nanocrystalline microspheres, the more contact points between the aggregates, which makes the cohesion between them stronger. Strong agglomeration tendency, resulting in longer grinding time, and before the additive is delivered to the electrolytic tank, the mixer must be turned on for stirring to prevent the coarse material from settling and blocking the pipeline

Even if it keeps stirring, it is difficult to keep the particles at the nanometer level and control them below 0.5 μm. It needs to be prepared and used immediately or the storage time should not exceed 12 hours, otherwise the electrolysis effect will be affected and the flexible arrangement of production will be restricted.

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