文章信息/Info

Title:

Synthesis of Binder-Free Titanium Dioxide Anode Materials for Rechargeable Sodium-Ion Batteries

文章編號:

1674-3962(2020)04-0287-08

作者:

謝嫚1; 李澤華1; 李帥杰2; 肖根華1; 羅熳3; 蔣文全3; 陳人杰1; 吳鋒1

1.北京理工大學材料學院，北京 100081）（2.寧德時代新能源科技股份有限公司，福建 寧德 352100）（3.有研工程技術研究院有限公司，北京 101417）

Author(s):

XIE Man1; LI Zehua1; LI Shuaijie2; XIAO Genhua1; LUO Man3;  JIANG Wenquan3; CHEN Renjie1; WU Feng1

(1.School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China) (2.Contemporary Amperex Technology Co., Ltd., Ningde 352100, China) (3.Research Engineering Technology Research Institute Co., Ltd., Beijing 101417, China)

關鍵詞:

鈉離子電池; 無粘結劑; 二氧化鈦; 納米線陣列; 負極

Keywords:

sodium�瞚on battery;  binder�瞗ree;  titanium dioxide;  nanowire array;  anode

分類號:

TM912；TB33

DOI:

10.7502/j.issn.1674-3962.201901006

文獻標志碼:

A

摘要:

作為電池的重要組成部分，電極材料直接影響電池的能量密度。電極材料在制作過程中往往會添加粘結劑以穩定極片結構，但粘結劑的加入會降低電極材料的比容量，影響其離子遷移速率。通過在經水熱反應刻蝕的鈦箔/網上原位生長二氧化鈦（TiO2）得到無粘結劑TiO2/Ti納米線陣列電極，并系統地研究不同鈦基底及水熱反應溫度對TiO2/Ti納米線陣列電極物理性能和電化學性能的影響。結果表明，不同鈦基底及水熱反應溫度均對生長的TiO2納米線的形貌和電化學性能有重要影響。其中通過220 ℃水熱反應生長在鈦網（0.15 mm）上的TiO2納米線呈蛛網狀，具有較大的比表面積，屬于銳鈦礦型TiO2，儲鈉過程主要由贗電容效應控制，且具有優秀的電化學性能：首周放電比容量為986 mAh g-1，庫倫效率為21.7%；隨后放電比容量逐漸穩定在240 mAh g-1左右；循環200周后放電比容量仍能達到228 mAh g-1，庫倫效率穩定在99.3%左右；即使在3200 mA g-1的超大電流密度下，放電比容量仍能達到152 mAh g-1。無粘結劑電極材料極大可以有限地提升電極材料的比容量，對未來高能量密度電池體系的設計具有一定的理論意義和參考價值。

Abstract:

As an important part of rechargeable sodium-ion batteries, electrode materials have a direct impact on the energy density of batteries. Binders tend to be added to stabilize the structure of the electrode during the fabrication of the electrode materials, but the addition of binders will reduce the specific capacity and affect the rate of ion migration of electrode materials. Here，binder-free titanium dioxide/titanium（TiO2/Ti）nanowire array electrodes are prepared by in-situ growth on titanium foil/mesh by hydrothermal process. The effects of different titanium substrates and hydrothermal reaction temperatures on the physical and electrochemical properties of TiO2/Ti nanowire array electrodes are investigated systematically. The results show that different titanium substrates and hydrothermal reaction temperatures heavily affect the micromorphology and electrochemical properties of the grown TiO2 nanowires. Among them, the TiO2 nanowires grown on titanium mesh (0.15 mm) by hydrothermal reaction at 220 ℃ (TiW-100-220) are cobweb-like with a large specific surface area. Moreover, the TiO2 nanowires grown on Ti mesh(0.15 mm) at 220 ℃ are anatase, which have a lower activation energy than TiO2 nanowires with other crystal structures. The main sodium storage process of TiW-100-220 is controlled by pseudocapacitance reaction, which has better electrochemical performance. The discharge capacity and coulombic efficiency of TiW-100-220 anode is 986 mAh g-1 and 21.7% in the first cycle. The discharge capacity of TiW-100-220 anode gradually stabilizes at 240 mAh g-1 from the second cycle. The discharge capacity of TiW-100-220 anode is 228 mAh g-1 after 200 cycles, and the coulombic efficiency is stable at about 99.3%. Even at a high current density of 3200 mA g-1, the discharge capacity of TiW-100-220 anode can still reach 152 mAh g-1. The binder-free electrode materials greatly increase the specific capacity of the electrode materials, which might be possible to offer theoretical significance and reference value to design a high energy density battery in the future.