A special morphology electrode active material precursor nickel manganese oxide

Abstract

The invention discloses an active electrode material precursor nickel manganese oxide with a special morphology. The active electrode material precursor nickel manganese oxide is prepared by the following preparation steps: (A) dissolving a mixture, of a bivalent nickel salt and a bivalent manganese salt, with a certain molar ratio of nickel ions and manganese ions with water to prepare a solution A, sequentially adding water, an assistant and a solvent to the mixture of carbonate and a surfactant, of which the molar weight is certain times of the nickel and manganese content of a nickel salt and a manganese salt, and stirring the mixture until the carbonate and the surfactant are dissolved, namely the solution is free of a sediment and transparent or semi-transparent, so as to prepare a solution B; (B) injecting the solution A into the solution B at a constant speed and further stirring the solution; and (C) centrifugally separating a reaction mixture, washing the sediment with water until no sulfate radical is detected out, carrying out a suction filtration to obtain nickel manganese carbonate, and roasting the nickel manganese carbonate, so as to obtain a nickel manganese oxide precursor. The precursor has the advantages of special morphology and uniform particle size distribution, and is free of environmental pollution, simple in equipment and short in reaction time; the nickel-manganese molar ratio is easy to control; the synthesis materials are abundant and low in price; and the conditions are easy to control.

Description

technical field [0001] The invention relates to the technical field of battery materials, and more specifically relates to a nickel-manganese oxide, a precursor of an electrode active material, with a special shape. Background technique [0002] Manganese oxide, manganese dioxide, etc. are widely used in the manufacture of lithium-ion batteries, alkaline zinc-manganese battery cathode materials or cathode materials. The appearance of manganese oxide is regular, the particle size is suitable, and the particle size distribution is uniform. It is a high-performance alkaline zinc-manganese battery cathode material and a prepared lithium-ion battery cathode material. It has an important technical index of good processing performance. Most of the positive electrode active materials used in the industrial manufacturing of lithium-ion secondary battery positive electrodes are LiCoO 2 , LiMn 2 o 4 , LiNiO 2 and other compounds, or compounds based on three compounds doped with eac...

AI Technical Summary

Problems solved by technology

[0014] First, the morphology of the precursors and cathode materials of lithium-ion battery cathode materials synthesized by existing synthesis techniques is relatively irregular, the morphology is difficult to control, the particle size is not uniform, the properties of materials and processing properties (especially the uniformity of dispersion ) is greatly restricted, which directly affects the consistency of the battery production process, that is, the product, and increases the manufacturing cost

Electrochemical technology consumes a lot of energy

[0015] Second, solid state reaction synthesis of manganese dioxide, manganese carbonate, LiNi 0.5 mn 1.5 o 4 The performance consistency of the precursors of lithium-ion battery cathode materials and cathode materials is not good, it is easy to mix impurities, the reaction speed is slow, the reaction time is long, the energy consumption is high, and usually only easily decomposed compounds can be used, and will not The oxides, hydroxides, nitrates, acetates, etc. that produce impurities are used as raw materials, and the synthesis cost is relatively high. Although a certain scale of production can be achieved, it is difficult to achieve wide application

[0016] Third, hydrothermal or hydrothermal LiNi 0.5 mn 1.5 o 4 Such as lithium-ion battery positive electrode material precursor or positive electrode material synthesis, although there are no shortcomings or defects such as uneven reaction, long reaction time and high cost of solid-state reaction synthesis technology, but there are also high energy consumption, complicated process steps, and control of process conditions. More stringent, higher technical requirements for equipment, etc., and the reaction is carried out in a solution state. Due to the limitation of the concentration, the amount of synthetic products is very limited. If the solution concentration is greatly increased or the volume of the reactor is increased, the synthesis technology will be greatly increased. Difficulty, product performance such as LiNi 0.5 mn 1.5 o 4 Uncertainty in the structure, morphology, particle size and electrochemical performance of etc. is also greatly increased.

As anode materials for batteries, nanomaterials also have significant defects: poor thermodynamic stability and severe surface chemical reactions (document "ChemInform Abstract: NanostructuredMaterials for Electrochemical Energy Conversion and Storage Devices[J]". Adv. Mater . 2008, 20: 2878-2887.) In addition, the dispersion of nanometer-sized cathode materials due to agglomeration is poor, which brings certain difficulties to the production of positive electrode sheets of batteries, and may also affect the potential comprehensive electrochemical performance of positive active materials. The effective performance of the performance, which in turn affects the actual electrochemical performance of lithium-ion batteries

Moreover, too fine nano-particle cathode materials will affect the mechanical properties of the cathode, processing and dispersion properties, etc., and then affect the discharge cycle performance of the material, the charge and discharge capacity of the battery, and the discharge energy decays quickly

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