Preparation method of carbon/iron oxide composite and lithium-ion battery

Abstract

The invention provides a preparation method of a carbon / iron oxide composite, comprising: mixing ferrous carbonate with a high-molecular organic matter, and heating and calcining in a protective atmosphere to obtain the carbon / iron oxide composite. Compared with the prior art, the method uses ferrous carbonate micro-particles as a raw material, the material may decompose into nano-scale iron oxide in subsequent high-temperature calcining, micro-structure of nanoparticles is accordingly obtained, the charge-discharge capacity is higher than that of solely nano-scale or micro-scale particles, and the structure is more stable; moreover, carbon material that is added may connect iron oxide active nanoparticles via three-dimensional network carbon, the carbon material can serve as a buffer and support, stress due to size changes of a substance is buffered, basic configuration of the substance is maintained, and the carbon material has high electrical conductivity so that the prepared carbon / iron oxide composite has high rate, high specific capacity and long cycle life.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a preparation method of a carbon / iron tetroxide composite material and a lithium ion battery. Background technique [0002] New energy Lithium-ion batteries are emerging energy sources. In order to meet the society's demand for high specific energy lithium batteries, people are actively exploring lithium battery anode materials with high theoretical specific capacity. [0003] The theoretical specific capacity of traditional lithium battery negative electrode material graphite is 372mAh / g, and the specific capacity of known lithium battery positive electrode materials (such as lithium iron phosphate, lithium cobalt oxygen, etc.) is also limited (100-200mAh / g), in order to adapt to people's In response to the demand for high-energy lithium batteries and the overall improvement of battery performance, researchers have explored and synthesized a series of a...

AI Technical Summary

Problems solved by technology

Many of the above-mentioned research works mainly focus on how to improve the conductivity of materials, discharge specific capacity or reduce the size of materials, etc., forming a situation where the material synthesis route is relatively complicated, the output is low, and the cost is high; at the same time, the initial discharge capacity of many works is considerable. But follow-up research is insufficient

[0005] In addition, the stability of transition metal oxides can also be improved by constructing micro-nano materials, but most of the current reports require multi-step regulation. Because the construction of special configurations requires control of ion concentration and the use of special organic solvents, etc., resulting in less product yield, The cost is increased; and the shape control is controlled by many factors, which are easily affected by parameters such as temperature, concentration, and pressure, so the operability of this method is poor

If carbon compounding is carried out again, the process will be increased, and at this time the oxide structure has basically formed, and it is difficult for the carbon material to penetrate evenly into the active particles during the carbonization process.

Images