Constructing Gradient Porous Structure in Thick Li₄Ti₅O₁₂ Electrode for High-Energy and Stable Lithium-Ion Batteries

Abstract

The manufacturing process for electrodes in lithium-ion batteries generally results in a nonuniform microstructure geometrically distributed in the through-thickness direction of an electrode. A porous structure was designed to decrease tortuosity and increase Li+ penetration in a thick Li4Ti5O12 (LTO) electrode. By using NaCl as a template, the porous LTO electrode with a high mass loading of 12 mg cm–2 was fabricated. Electrochemical performance for the LTO electrode with different porosities was comparatively studied. To achieve higher volume energy density, a gradient porous LTO electrode was prepared. As a result, the thick LTO electrode with a high mass loading of 20 mg cm–2 can deliver a high capacity of 150 mAh g–1 at 1 C with almost no ohmic drop under charge/discharge for 40 cycles.

From Fundamental Understanding to Engineering Design of High‐Performance Thick Electrodes for Scalable Energy‐Storage Systems

“…Because increasing research attention has been paid to thick electrode design, an overview of the research statistics in this field is essential to benchmark the current research status. Here, we summarize the information on the abovementioned electrode design parameters as well as energy/power density indicators from 62 publications related to thick electrodes, [ 8,9,12–15,20,21,24,39,40,43–45,50,62–104 ] (Table S2, Supporting Information) and the results of the statistical analysis are discussed in the following section.…”

Multi-length scale microstructural design of lithium-ion battery electrodes for improved discharge rate performance

“…5 For instance, thicker electrodes, low porosity and heavy calendering are common material design strategies for high energy density cells, which inevitably suffer from large polarization due to the poor percolation and high tortuosity of the pore network, 6,7 consequently sacrificing the rate capability of the cell. 8 Accordingly, researchers have been exploring either advanced electrode architectures, such as gradient porosity/pore size 9,10 and directional pore phase architectures, 11 or innovational flexible 1D batteries with hybrid electrodes to overcome this challenge. 12 Despite the remarkable performance improvement of these designs, the scalability, cost and structural integrity remain of concern for large-scale electrode manufacturing and commercialization.…”

Nano‐Sized Niobium Tungsten Oxide Anode for Advanced Fast‐Charge Lithium‐Ion Batteries

“…[19][20][21] Zn 2 Nb 34 O 87 and Nb 8 W 9 O 47 display superior practical capacity of 153.1 and 147 mAh g -1 accompanied by almost 100% coulomb efficiency at 10 C, respectively, which outperforms those of TiO 2 and Li 4 Ti 5 O 12 . [22][23][24][25][26] Moreover, BaNb 3.6 O 10 nanowires exhibit structural stability and reversibility since preserving 60% of initial capacity after 5000 cycles at 1000 mA g -1 . Therefore, the nanostructured morphology may be beneficial to effectively improve the electrochemical properties by shorting ion/electron transport passageways, enhancing Li + intercalation kinetics, which has also been proved in other nanostructured materials (Cr 0.5 Nb 24.5 O 62 , [27] GeNb 18 O 47 , [28] GaNb 11 O 29 ).…”