Preparation method and application of precursor cobalt hydroxide

Abstract

The invention discloses a preparation method of precursor cobalt hydroxide. The preparation method comprises the steps of S1, preparing a cobalt salt solution, a strong alkali solution and an ammoniawater solution; S2, dropwise adding the prepared strong base and ammonia water into a water-containing reaction kettle, and uniformly stirring at a constant temperature to obtain a reaction base solution of which the pH value is 11.0-11.5 and the ammonia concentration is 0.4-0.8 mol / L; S3, adding the prepared cobalt salt solution, strong alkali solution and ammonia water into the reaction kettle according to a preset feeding speed to carry out coprecipitation reaction, and maintaining preset stirring strength and reaction temperature in the coprecipitation reaction process, wherein the pH value of the reaction is 11.0-11.5 and the ammonia concentration is 0.4-0.8 mol / L; and S4, separating and washing to obtain cobalt hydroxide. The invention further discloses a preparation method of a positive electrode material for a quick-charge lithium ion battery. According to the invention, the lithium cobalt oxide is promoted to expose more active crystal faces {010}, and the quick charge and quick discharge performance of the lithium battery is improved.

Description

technical field [0001] The invention relates to the field of preparation methods of lithium cobalt oxide, a positive electrode material of lithium batteries, in particular to a preparation method of a precursor cobalt hydroxide and its application. Background technique [0002] At present, the microscopic morphology of lithium cobaltate, the positive electrode material used in lithium-ion batteries, is mainly some irregular primary particles or secondary agglomerated particles composed of primary particles, and the exposed crystal planes on the surface of the primary particles are irregular. The existing lithium cobalt oxide cathode material is divided into two steps. The first step is to prepare the precursor cobalt hydroxide (Co(OH) 2 ), the second step is lithium cobalt oxide (LiCoO 2 ) preparation. In the prior art, no large research has been done on the process parameters in these two steps. In order to make the small primary particle Li + The path of intercalation a...

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Problems solved by technology

In the prior art, no large research has been done on the process parameters in these two steps. In order to make the small primary particle Li + The path of intercalation and extraction is shorter and the time is faster. For fast-charging lithium-ion batteries, it is usually achieved by adjusting the proportion of small particles in the positive electrode material to achieve fast charging and fast-discharging of lithium-ion batteries. The improvement method is relatively simple and the effect is limited.

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