Synergic coating and doping effects of Ti-modified integrated layered–spinel Li1.2Mn0.75Ni0.25O2+δ as a high capacity and long lifetime cathode material for Li-ion batteries†,Journal of Materials Chemistry A

当前位置： X-MOL 学术 › J. Mater. Chem. A › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Synergic coating and doping effects of Ti-modified integrated layered–spinel Li1.2Mn0.75Ni0.25O2+δ as a high capacity and long lifetime cathode material for Li-ion batteries†
Journal of Materials Chemistry A ( IF 10.7 ) Pub Date : 2018-01-02 00:00:00 , DOI: 10.1039/c7ta09118d
Ngoc Hung Vu _{1,

2,

3,

4,

5} , Jong Chan Im _{1,

2,

3,

4,

5} , Sanjith Unithrattil _{1,

2,

3,

4,

5} , Won Bin Im _{1,

2,

3,

4,

5}

Affiliation

An integrated layered–spinel material with a nominal composition of (1 − x)Li_1.2Mn_0.6Ni_0.2O₂·xLiMn_1.5Ni_0.5O₄ (0.15 < x < 0.3) and crystal defects has been found to be a promising cathode material with a high capacity of 280 mA h g⁻¹. However, capacity fading arising from Mn²⁺ dissolution occurred at low voltages and long cycling times. To improve the cycling stability while preserving the advantages of this cathode material, a synergic coating and doping approach was studied. This method yields a coating with a similar, but more stable, structure to that of the pristine sample. This coating is achieved by the bulk doping of the surface while maintaining the ratio of layered to spinel phases. The coating layer had a thickness of 12 to 18 nm, which increased with increasing Ti doping, and protected the sample at low voltages while maintaining the ion and charge transport channels on the surface. The Ti-doped sample enhanced the capacity retention by up to 97% after 100 cycles at C/10 and 89% after 200 cycles at 1C compared to 75% and 74% of the pristine sample, respectively. The optimized sample delivered a stable capacity of 270, 250, and 145 mA h g⁻¹ at C/20, C/10, and 1C respectively. This study provides an effective approach to improve the cycling performance of integrated spinel-layered cathode materials.

中文翻译：

Ti改性集成层-尖晶石型Li _1.2 Mn _0.75 Ni _0.25 O 2 _{+ δ的}协同涂层和掺杂效应，作为锂离子电池的高容量和长寿命阴极材料†

已发现标称成分为（1- x）Li _1.2 Mn _0.6 Ni _0.2 O ₂ · x LiMn _1.5 Ni _0.5 O ₄（0.15 < x <0.3）和晶体缺陷的集成层状-尖晶石材料是有前途的阴极具有280 mA hg ^-1的高容量的材料。但是，Mn ²⁺引起的容量衰减溶解发生在低电压和长循环时间下。为了在保持这种阴极材料优点的同时提高循环稳定性，研究了一种协同涂覆和掺杂方法。该方法产生的涂层具有与原始样品相似但更稳定的结构。这种涂层是通过在保持层状与尖晶石相之比的同时对表面进行整体掺杂而实现的。涂层的厚度为12至18 nm，该厚度随Ti掺杂的增加而增加，并在低电压下保护样品，同时在表面上保持离子和电荷传输通道。掺杂Ti的样品在C / 10下100次循环后的容量保持能力提高了97％，在1C下200次循环后的容量保持能力提高了89％，而原始样品分别为75％和74％。^分别在C / 20，C / 10和1C时为^-1。这项研究提供了一种有效的方法来提高集成的尖晶石层阴极材料的循环性能。

更新日期：2018-01-02

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11