Modified spinel lithium manganate for secondary lithium ion battery and preparation method thereof

A technology of spinel lithium manganese oxide and lithium-ion batteries, which is applied in battery electrodes, circuits, electrical components, etc.

Inactive Publication Date: 2012-04-11
WUXI LITAI ENERGY TECH
View PDF6 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, since the metal oxide is coated on the surface of spinel lithium manganese oxide in granular form, the coating layer is discontinuous, the film-forming property is poor, and the coating thickness is difficult to control, so it is actually impossible to effectively inhibit the dissolution of manganese, especially The cycle performance of modified spinel lithium manganese oxide is still poor under the condition of high temperature charge and discharge
In addition, metal compounds are electronic insulators, and the prepared electrode materials have poor rate characteristics.
[0007] The above prior art shows that although various efforts have been made to modify LiMn2O4, the The actual effect achieved is limited, and the above shortcomings still have room for improvement

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
  • Modified spinel lithium manganate for secondary lithium ion battery and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] Example 1: LiMn 2 o 4 Bulk - 5wt% SiO 2 Coating-2wt% carbon (glucose as carbon source) coating composites preparation and electrochemical performance testing.

[0042] Prepare LiMn by comparative example 1 method 2 o 4 Body material. Weigh LiMn 2 o 4 Body powder 100g, according to SiO after coating 2 Accounting for 5wt% of spinel lithium manganese oxide powder, weigh 17.3g of ethyl orthosilicate, measure ethyl orthosilicate: ethanol: single distilled water = 1:8:10 volume ratio, measure ethanol and deionized water, adjust with ammonia water pH=9, stir in 80°C water bath for 10min, after dissolving into a uniform and transparent tetraethosilicate sol, add the weighed LiMn 2 o 4 The bulk powder is stirred while heating at 100°C to make it fully and uniformly dispersed, and then baked in an oven at 60°C for 12 hours after forming a gel. The dried powder was treated in a muffle furnace at 500 °C for 4 h. After cooling, a spinel lithium manganese oxide material co...

Embodiment 2

[0043] Example 2: LiMn 2 o 4 Bulk-5wt%SiO 2 Coating-5wt% carbon (glucose as carbon source) coating composites preparation and electrochemical performance testing.

[0044] The final coated carbon accounts for the bulk material LiMn 2 o 4 5wt% of the others, as in Example 1 to prepare spinel lithium manganese oxide-silicon dioxide-carbon three-layer composite material. Compared with Comparative Examples 2 and 3, this material has better cycle performance and rate characteristics. The capacity retention rate after 100 cycles at room temperature is 95%, and the capacity retention rate at 55 °C is 92%. The cycle performance is better than that of the examples. 1 has been further improved, but the rate characteristic has declined slightly, and the discharge capacity ratio of 5C / 0.2C is 85%. The experimental results are shown in Table 1.

Embodiment 3

[0045] Example 3: LiMn 2 o 4 Bulk-5wt%SiO 2 Coating-10wt% carbon (glucose as the carbon source) coating composites preparation and electrochemical performance testing.

[0046] The final coated carbon accounts for the bulk material LiMn 2 o 4 The 10wt% of other preparations of spinel lithium manganate-silicon dioxide-carbon three-layer composite material as described in Example 1. A battery was fabricated according to Comparative Example 1 by using the above-mentioned modified spinel lithium manganese oxide material. Compared with Example 2, the cycle performance is further improved. The capacity retention rate after 100 cycles at room temperature is 97%, the capacity retention rate at 55 °C high temperature is 92%, the 5C / 0.2C discharge capacity ratio is 83%, and the rate performance is slightly reduced. . The experimental results are shown in Table 1.

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

No PUM Login to view more

Abstract

The invention is modification of spinel lithium manganate for secondary lithium ion batteries and its preparation method, and is characterized in that the spinel lithium manganate is orderly coated with a silica film and an outer carbon film, which forms a composite material with a spinel lithium manganate-silica-carbon three-layer core-shell structure. The coating is performed by a sol-gel method and a solid phase coating method respectively. The composite material with the three-layer core-shell structure has excellent rate capability, and has a 5C / 0.2C discharge capacity ratio of up to 86%. The normal-temperature and high-temperature cycle performance are greatly improved; the capacity retention rate for 100 cycles of normal-temperature 1C is up to 98%; the capacity retention rate for 100 cycles of 55 DEG C 1C is up to 94%, such as a modified spinel lithium manganate material coated with Li1.04Al0.05Mn1.95O4 body-5 wt% silica coating-5 wt% carbon coating. The problems of unstable cycle performance and poor rate capability of the spinel lithium manganate for secondary lithium ion batteries are effectively solved. The preparation method of the invention is simple and practical, low in cost, and is applicable to large-scale production.

Description

technical field [0001] The invention is an improvement to the modified spinel lithium manganese acid for secondary lithium ion batteries and its preparation method, in particular to a modified spinel manganese acid for secondary lithium ion batteries with stable cycle performance and excellent rate characteristics lithium. Background technique [0002] As a new generation of green secondary batteries, lithium-ion batteries have the advantages of small size, light weight, large capacity, small self-discharge, long cycle life, and no memory effect. The application has attracted more and more attention, especially as a power source to replace traditional petrochemical Energy is even more concerned. [0003] The performance of lithium-ion power batteries largely depends on the positive electrode material. Among the developed positive electrode materials, lithium manganese oxide with spinel structure and lithium iron phosphate with olivine structure have good rate charge and dis...

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
Patent Type & Authority Applications(China)
IPC IPC(8): H01M4/505H01M4/1391
CPCY02E60/122Y02E60/10
Inventor 王张志黄兵
Owner WUXI LITAI ENERGY TECH
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap