Silicon-carbon alloy cathode material for lithium ion batteries and preparation method thereof

A lithium-ion battery, alloy negative electrode technology, applied in the direction of battery electrodes, circuits, electrical components, etc., can solve the problems of electrode material pulverized electrode performance, poor battery cycle performance, deterioration, etc., to achieve easy operation, low cost, and high preparation process simple effect

Active Publication Date: 2011-02-09
GUANGDONG DONGDAO NEW ENERGY
View PDF5 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the large volume change of the alloy negative electrode in the process of lithium intercalation and deintercalation can easily lead to

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Silicon-carbon alloy cathode material for lithium ion batteries and preparation method thereof
  • Silicon-carbon alloy cathode material for lithium ion batteries and preparation method thereof
  • Silicon-carbon alloy cathode material for lithium ion batteries and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0019] The preparation method of the lithium-ion battery silicon-carbon alloy negative electrode material of the present invention adopts general-purpose equipment, first alloys aluminum-silicon and then composites it with graphite powder, then adopts asphalt coating treatment, and finally drys and burns to obtain the required silicon-carbon alloy negative electrode Material. Include the following steps:

[0020] 1. Add additives accounting for 3-6% of the total weight of the lithium-ion silicon-carbon alloy negative electrode material, pitch accounting for 25-30% of the total weight of the material, and 4-8 μm elemental silicon powder accounting for 7-15% of the total weight of the material (vacuum packaging, After unpacking, put it into a glove box for storage), add absolute ethanol, the amount is to soak all the above-mentioned materials, after mixing, add it to a ball mill and stir the wet ball mill at a speed of 200-600rpm, preferably 400rpm, for 10-15h, and then mix the ...

Embodiment 1

[0024] Embodiment 1, weigh the silicon powder whose weight is 7% of the total weight of the lithium-ion silicon-carbon alloy negative electrode material, the average particle diameter 4~8 μ m, the aluminum powder whose weight is 3% of the total weight of the material, the average particle diameter 5~10 μ m, 25% of the total weight of the material asphalt for industrial use is poured into the high-energy ball mill tank, and then absolute ethanol is added in the high-energy ball mill tank. Soak ingredients well. Mix with wet ball mill at 400rpm for 10 hours, then weigh 65% of the total weight of spherical natural graphite and add it to the ball mill tank, add absolute ethanol, soak all ingredients, mix with high-speed ball mill for 1 hour, and then stir at 250rpm at low speed 1.5h. Take out suction filtration and carry out vacuum drying, and its vacuum degree is 10 -2 Pa, the drying temperature is 80°C, the drying time is 10h, and then it is lowered to room temperature, and a ...

Embodiment 2

[0027]Embodiment 2, weigh the silicon powder whose weight is 8% of the total weight of the lithium-ion silicon-carbon alloy negative electrode material, the average particle diameter 4~8 μ m, the aluminum powder whose weight is 5% of the total weight of the material, the average particle diameter 5~10 μ m, The industrial asphalt whose weight is 26% of the total weight of the material is poured into a high-energy ball mill tank, and absolute ethanol is added to fully soak the ingredients in the absolute ethanol. 200rpm rotating speed wet ball mill mixed 15h, then weighed spherical natural graphite and artificial graphite (mass ratio 1: 1) that weighed 61% of the total weight of the pole material, joined in the ball mill jar, and added absolute ethanol, soaked all ingredients, Then high-speed ball milling and mixing for 1.5 h, and then stirring at a low speed of 150 rpm for 3 h. Take out suction filtration and carry out vacuum drying, and its vacuum degree is 10 -2 Pa, the dryi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Granularityaaaaaaaaaa
Granularityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a silicon-carbon alloy cathode material for lithium ion batteries and a preparation method thereof. The invention aims to enhance the specific capacity of the lithium ion battery and have excellent cycle performance. The cathode material comprises the matrix which is physically compounded from a silicon alloy and graphite powder, and the surface of the cathode material is coated with a carbon material. The preparation method comprises the following steps: mixing aluminium powder, asphalt and simple substance silicon powder, adding graphite, mixing, drying and roasting to obtain the silicon-carbon alloy composite material. Compared with the prior art, the reversible specific capacity of the silicon-carbon alloy cathode material is higher than 590 mAh/g, the first cycle coulombic efficiency is higher than 75%, and the capacity conservation rate after 60 cycles is higher than 92%; the silicon-carbon alloy cathode material has excellent lithium embedding and removing capacity, and high cycle stability; and the preparation technique has the advantages of simple operation and low cost, and is suitable for high-capacity lithium ion battery cathode materials for various portable devices.

Description

technical field [0001] The invention relates to a battery negative electrode material and a preparation method thereof, in particular to a lithium ion battery negative electrode material and a preparation method thereof. Background technique [0002] At present, a large number of commercial lithium-ion batteries use graphite-based carbon materials as negative electrode materials. However, due to the low mass-specific capacity and poor high-rate charge-discharge performance of graphite-based carbon materials, the theoretical value is 372mAh / g. The capacity is 330-360mAh / g, especially the volume specific capacity is quite limited. Therefore, there is very little space for further improving its specific capacity, which is far from meeting the needs of future high-capacity and long-life electronic equipment. In recent years, metal and alloy materials are new and efficient lithium storage anode material systems that have been studied more, among which pure metal silicon and sili...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): H01M4/133H01M4/38H01M4/1393
CPCY02E60/122Y02E60/10
Inventor 吴其修张万红
Owner GUANGDONG DONGDAO NEW ENERGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products