文章信息/Info

Title:

Study on Preparation and Electrochemical Properties of Novel Composite Fluorinated Carbon Cathode Material

文章編號:

1674-3962(2021)08-0567-06

作者:

林錦芳; 李琦旸

（惠州億緯鋰能股份有限公司，廣東 惠州 516000）

Author(s):

LIN Jinfang;  LI Qiyang

(EVE Energy Co., Ltd., Huizhou 516000, China)

關(guān)鍵詞:

鋰/氟化碳電池; 正極材料; 復(fù)合分級氟化碳; 作用機理; 電化學(xué)性能

Keywords:

lithium/fluorinated carbon battery;  cathode material;  composite hierarchical fluorinated carbon;  reaction mechanism;  electrochemical performance

分類號:

TB332；TM911

DOI:

10.7502/j.issn.1674-3962.202104025

文獻標志碼:

A

摘要:

鋰/氟化碳電池具有高達2180 Wh·kg-1的理論能量密度，但因氟化碳正極材料導(dǎo)電性差、振實密度低，導(dǎo)致該材料在電池應(yīng)用中存在容量發(fā)揮率低的問題。前期研究表明，氟化碳材料顆粒尺寸、比表面積及氟化度等理化性質(zhì)對其電子導(dǎo)電性和容量發(fā)揮率有顯著影響。在研究了分級氟化碳材料微觀形貌、比表面積及粒徑的基礎(chǔ)上，使用物理研磨分散方法制備了新型復(fù)合分級氟化碳正極材料。通過調(diào)控分級氟化碳材料的質(zhì)量比例，研究了復(fù)合氟化碳正極材料的形貌、極片結(jié)構(gòu)及電化學(xué)作用機理，并進一步對比了以復(fù)合氟化碳材料為正極材料的電池的阻抗及電化學(xué)性能。研究結(jié)果表明，采用復(fù)合分級氟化碳材料減少了極片的孔隙率，增加了顆粒之間的接觸緊密度，有效降低了電池的電荷轉(zhuǎn)移電阻，相比于采用單一氟化碳CF01為正極材料的電池，采用復(fù)合分級氟化碳CF73為正極材料的電池的電阻下降了62%，比能量提升了4.1%。

Abstract:

The theoretical energy density of lithium/fluorinated carbon battery (Li/CFx) is as high as 2180 Wh·kg-1. However, due to the poor electrical conductivity and low vibrational density of the fluorinated carbon (CFx), there is a problem of low capacity utilization rate of the CFx materials in battery applications. Previous studies have shown that the physical properties and chemical properties such as particle size, specific surface area and degree of fluorination have a great influence on the electronic conductivity and capacity utilization of CFx. In this paper, based on the study of the microstructure, specific surface area and particle size of hierarchical CFx, novel composite hierarchical CFx were prepared by physical ball milling method. By adjusting the mass ratio of hierarchical CFx, the micro morphology, electrode structure and electrochemical mechanism of the novel composite CFx were studied, and the impedance and electrochemical performance of batteries with composite CFx as cathode material were further compared. The results show that the novel composite CFx reduces the porosity of the electrode, increases the contact tightness between the particles and effectively reduces the charge transfer resistance of the battery. The battery uses CF73 composite as cathode material, whose resistance decreases by 62% and specific energy increases by 4.1% compared with the battery using single CF01 as cathode material.