Nature Communications
·
2018
·Vol. 9
·期 1
·1-11
·
IF 12.353
Qian Jiawei,Liu Lei,Yang Jixiang,Li Siyuan,Wang Xiao,Zhuang Houlong L.,Lu Yingying
Lithium cobalt oxide, as a popular cathode in portable devices, delivers only half of its theoretical capacity in commercial lithium-ion batteries. When increasing the cut-off voltage to release more capacity, solubilization of cobalt in the electrolyte and structural disorders of lithium cobalt oxide particles are severe, leading to rapid capacity fading and limited cycle life. Here, we show a class of ternary lithium, aluminum, fluorine-modified lithium cobalt oxide with a stable and conductive layer using a facile and scalable hydrothermal-assisted, hybrid surface treatment. Such surface treatment hinders direct contact between liquid electrolytes and lithium cobalt oxide particles, which reduces the loss of active cobalt. It also forms a thin doping layer that consists of a lithium-aluminum-cobalt-oxide-fluorine solid solution, which suppresses the phase transition of lithium cobalt oxide when operated at voltages >4.55 V.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Yunchao Liao,Zhengfeng Wang,Xinyi Dai,Haijun Chen,Fuzhong Wu,Jingze Li,Yi Mai,Shuie Li
Surface coating is an effective way to suppress the structural collapse and surface side reactions of LiCoO2(LCO) at high voltage. Herein, KAlF4 is used as the raw material for coating modification and combining the wet chemical method and high-temperature solid-phase method to form a dense LiF, KF, and LiCo1–xAlxO2 composite coating layer on the surface of LCO. The fluoride composite coating layer can stabilize the surface of the material, and the solid solution phase can accelerate the transport of Li+ while stabilizing the surface. The synergistic effect of the composite coating phase has a positive effect on mitigating the surface side reactions and structural collapse of LCO at high cutoff voltages above 4.5 V. The modified sample had a first discharge specific capacity of 216.3 mAh/g at 0.5 C in the high-voltage range of 3.0–4.7 V and still had capacity retention of up to 60.4% after 200 cycles, while only 5.8% of unmodified LCO samples remained after 160 cycles. The improved electrochemical performance is attributed to the stabilized surface and phase structure, improved lithium ion diffusion coefficient induced by composite coating as evidenced by electrochemical impedance spectroscopy, cyclic voltammetry, and scanning electron microscopy.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Energy Materials
·
2023
·Vol. 13
·期 20
·2204272
·
IF 27.8
Kanglong Guo,Chunlei Zhu,Huaping Wang,Shihan Qi,Junda Huang,Daxiong Wu,Jianmin Ma
Increasing the cut-off voltage of cathodes can improve the energy density of Li||LiCoO 2 batteries. However, the electrolyte and cathode suffer from oxidation and deterioration at high voltage, respectively, which lead to rapid battery degradation. Herein, a uniform, highly Li + conductive cathode electrolyte interphase (CEI) is constructed by using bis-(benzenesulfonyl)imide (BBSI) as an additive to stabilize Li||LiCoO 2 batteries at 4.6 cut-off voltage with superior cycling and high-rate performance. Such a CEI is comprised of LiF and conductive Li + moieties (e.g., Li 2 S and Li 3 N), which can improve the Li + migration, alleviate cathode degradation, and other secondary degradation factors caused by uneven local Li + intercalation/deintercalation. As expected, Li||LiCoO 2 batteries with a 1% BBSI-containing electrolyte sustain 81.30% of initial capacity after 300 cycles at 0.5C, and 88.27% of initial capacity even after 500 cycles at 2C/3C.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Nano
·
2021
·
IF 8.109
P. Zhang,C. Xie,G. Han,Q. Zhu,L. Chen,M. Jin,Q. Liu,Y. Zhou,Q. Sun,J. Xie
Chemical/electrochemical instability of LiCoO 2 (LCO) at high voltage limits its deliverable capacity and thereby energy density of the battery , although it has a high theoretical capacity of 274 mAh/g. In this study, stable cycling of LiCoO 2 at a voltage as high as 4.55 V can be achieved by simultaneous lattice doping with Mg (LMCO) and surface coating with a NASICON-type Li 1.4 Al 0.4 Ti 1.6 (PO 4 ) 3 (LATP) solid-state electrolyte. Uniform coating can be realized by a facile Pechini route combined with solid-phase calcination . The LCO with 4 wt% LATP coating and 2 at% Mg doping (4 wt% LATP/LMCO-0.02) can deliver a high capacity of 204 mAh/g in the voltage range of 3.0–4.55 V (vs. Li/Li + ) at 0.4C. After 300 cycles at 0.4C, the 4 wt% LATP/LMCO-0.02 material can maintain 86.2% of its initial capacity, significantly superior to those of undoped and/or uncoated materials. The results show that both doping and coating are critical in inhibiting structural change of LCO and electrolyte decomposition at a deeply charged state of LiCoO 2 material.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Materials Chemistry Frontiers
·
2021
·Vol. 5
·期 16
·6171-6181
·
IF 6.482
Liewu Li,Qi Yuan,Shenghua Ye,Yonghuan Fu,Xiangzhong Ren,Qianling Zhang,Jianhong Liu
The layered LiCoO2 cathode plays a key role in high-energy-density lithium-ion batteries (LIBs), delivering a capacity of ∼185 mA h g−1 at a high cut-off voltage of 4.5 V (vs. Li/Li+). However, its practical applications in high-voltage LIBs are limited by a severe side reaction and an irreversible structure transition during cycling. Herein, we report a facile surface coating technique to prepare the Li4SiO4-coated LiCoO2 composite (LiCoO2@Li4SiO4) to confront the issue of instability and increase the capacity of the LiCoO2 cathode at 4.5 V. Notably, the LiCoO2@Li4SiO4 electrode exhibits an exceptionally high initial discharge capacity (180.7 mA h g−1 at 0.1 C), a significantly enhanced rate capability (147.2 mA h g−1 at 5 C), and long-term cycling stability (capacity retention of 82.2% after 500 cycles at 2 C). The experimental results demonstrate that the Li4SiO4 coating could effectively reinforce the structural stability of the LiCoO2@Li4SiO4 electrode during cycling. Furthermore, the density functional theory calculation results further confirm that the Li4SiO4 coating facilitates the rapid Li+ diffusion at the LiCoO2@Li4SiO4 electrode. This work provides a potential strategy for interface engineering of the 4.5 V LiCoO2 cathode for high-energy-density LIBs.
研究领域:
材料科学
·
电化学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2021
·Vol. 13
·期 16
·7822-7830
·
IF 7.79
Yuwan Dong,Panzhe Su,Guanjie He,Huiling Zhao,Ying Bai
With high theoretical capacity and tap density, LiCoO2 (LCO) cathode has been extensively utilized in lithium-ion batteries (LIBs) for energy storage devices. However, the bottleneck of structural and interfacial instabilities upon cycling severely restricts its practical application at high cut-off voltage. From another perspective, the compatibility between the electrode and electrolyte is highly valued in the development of all-solid-state batteries. Herein, we construct a compatible interface between Li7La3Zr2O12 (LLZO) and LCO through a facile surface modification strategy, which significantly improves the cycling stability of LCO at a high cut-off voltage of 4.5 V. Characterization results demonstrate that the LCO@1.0 LLZO sample delivers a desirable capacity retention of 76.8% even after 1000 cycles at 3.0–4.5 V with the current density of 1 C (1 C = 274 mA g−1). Further investigation indicates that the LLZO modification layer could protect the LCO electrode through effectively alleviating the side reactions, which not only facilitates the Li+ transportation at the interface but also mitigates the bulk structure degradation. Moreover, it is also established that a small amount of La and Zr ions could gradiently migrate into the surface lattice of LCO to generate a thin layer of the surface solid solution Li–Co–La–Zr–O. Thus formed pinning region between surface modified LLZO and LCO cathode could contribute both to their mechanical compatibility and Li+ kinetics behavior upon repeated cycling. This work not only provides a strategy in broadening the operation potential and extracting higher capacity of LCO but also sheds light on constructing compatible interfaces in LIBs, especially for all-solid-state energy storage and conversion devices.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
PubMed
高影响因子
Energy Technology
·
2017
·Vol. 5
·期 11
·1979-1989
·
IF 2.789
Chunguang Pang,Gaojie Xu,Weizhong An,Guoliang Ding,Xiaochen Liu,Jingchao Chai,Jun Ma,Haisheng Liu,Guanglei Cui
The effectiveness of multicomponent functional additives on the performances of lithium ion batteries has received increasing attention. Tris(2 H -hexafluoroisopropyl) borate (THFPB) additive can totally suppress the appearance of a crystallized complex between LiPF 6 and adiponitrile (ADN). Herein, ADN, THFPB, and cyclohexylbenzene are demonstrated to be an effective three-component functional additive in LiPF 6 -based carbonate electrolyte that improves the cyclability and rate capabilities of LiCoO 2 /graphite full cells charged to 4.4, 4.45, and 4.5 V, respectively. By systematic characterization, it is demonstrated rationally that, with the help of the three-component functional additive, the electrolyte is stabilized and new types of less resistant, thinner, more protective solid–electrolyte interfaces are constructed simultaneously on the surfaces of both electrodes.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 41
·24533-24541
·
IF 3.119
Huiling Chen,Yuehua Wen,Yue Wang,Songtong Zhang,Pengcheng Zhao,Hai Ming,Gaoping Cao,Jingyi Qiu
For high-voltage cycling of lithium-ion batteries, a gel polymer Li-ion conductor layer, P(VDF-HFP)/LiTFSI (PHL) with high electrochemical stability has been coated on the surfaces of as-formed LiCoO2 (LCO) cathodes by a solution-casting technique at low temperature. An LCO cathode coated with around 3 μm thickness of the PHL ultrathin membrane, retains 88.4% of its original capacity (184.3 mA h g−1) after 200 cycles in the 3.0–4.6 V range with a standard carbonate electrolyte, while the non-coated one retains only 80.4% of its original capacity (171.5 mA h g−1). The reason for the better electrochemical behaviors and high-voltage cycling is related to the distinctive characteristics of the PHL coating layer that is compact, has highly-continuous surface coverage and penetrates the bulk of LCO, forming an integrated electrode. The PHL coating layer plays the role of an ion-conductive protection barrier to inhibit side reactions between the charged LCO surface and electrolyte, reduces the dissolution of cobalt ions and maintains the structural stability of LCO. Further, the PHL coated LCO cathode is well preserved, compared to the uncoated one which is severely cracked after 200 cycles at a charging cut-off voltage of 4.6 V.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Zhengfeng Wang,Xinyi Dai,Haijun Chen,Fuzhong Wu,Yi Mai,Shuie Li,Yijing Gu,Jingze Li,Aijun Zhou
The surface and interface stability of the electrode is an important factor affecting the electrochemical performance of the battery, and surface modification is an effective means to stabilize the electrode surface interface. In this paper, a TiO2–LiF composite coating layer with very stable chemical properties on the LiCoO2 (LCO) surface is prepared in one step. At the same time, surface doping is realized, which provided a stable surface structure for LCO and stabilized the interface between the electrode and electrolyte. Electrochemical test results show that in the range of 3–4.5 V, the capacity retention rate of the sample with a coating amount of 1% is 97.4% after 110 cycles at 0.2 C and a discharge capacity of 151.5 mAh g–1 at 5 C, while the bare electrode is only 67% (110th cycle) and 50.7 mAh g–1 under the same conditions. Even at 0.5 C within 3–4.6 V, the capacity retention rate of the coated sample is still as high as 88.6% after 100 cycles, showing excellent high-voltage cycle stability. Studies such as cyclic voltammetry and electrochemical impedance spectroscopy show that the improvement in electrochemical performance is due to the coating layer effectively stabilizing the LCO surface composition and structure, alleviating the structural degradation of LCO, and optimizing the lithium-ion transport channel.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2023
·Vol. 16
·期 20
·e202300517
·
IF 8.4
Guozhong Lu,Ying Jiang,Xiang Wu,Fushan Geng,Chao Li,Bingwen Hu,Ming Shen
Graphical Simultaneous surface coating with Li 2 TiO 3 /Li(TiMg) 1/2 O 2 and bulk Mg-doping for LiCoO 2 is proposed to achieve long-life Li 10 GeP 2 S 12 -based ASSLBs. The Li 2 TiO 3 /Li(MgTi) 1/2 O 2 coating layers effectively suppress the interface side reactions and the space charge layer effect. The gradient Mg doping stabilizes the lattice structure of LiCoO 2 under local overcharging. Interfacial side reactions and space charge layers between the oxide cathode material and the sulfide solid-state electrolytes (SSEs), along with the structural degradation of the active material, significantly compromise the electrochemical performance of all-solid-state batteries (ASSLBs). Surface coating and bulk doping of the cathodes are considered the most effective approaches to mitigate the interface issues between the cathode and SSEs and enhance the structural integrity of composite cathodes. Here, a one-step low-cost means is ingeniously designed to modify LiCoO 2 (LCO) with heterogeneous Li 2 TiO 3 /Li(TiMg) 1/2 O 2 surface coating and bulk gradient Mg doping. When applied in Li 10 GeP 2 S 12 -based ASSLBs, the Li 2 TiO 3 and Li(TiMg) 1/2 O 2 coating layers effectively suppress interfacial side reactions and weaken space charge layer effect. Furthermore, gradient Mg doping stabilizes the bulk structure to mitigate the formation of spinel-like phases during local overcharging caused by solid-solid contact. The modified LCO cathodes exhibit excellent cycle performance with a capacity retention of 80 % after 870 cycles. This dual-functional strategy provides the possibility for large-scale commercial implementation of cathodes modification in sulfide based ASSLBs in the future.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Materials Interfaces
·
2021
·Vol. 8
·期 15
·2100624
·
IF 6.147
Zhen Sun,Yanqing Lai,Na lv,Yaqi Hu,Bingqin Li,Shenghao Jing,Liangxing Jiang,Ming Jia,Jie Li,Shiyou Chen,Fangyang Liu
Solid-state batteries exhibit promising prospects due to their potential in terms of safety and energy density. Sulfide solid electrolytes have received much attention due to their high ionic conductivity (about 10 −2 S cm −1 ). However, high side reactions between solid sulfide electrolytes and oxide cathodes, such as LiCoO 2 , have hampered the development of all-solid-state sulfide batteries. Here, first-principles calculations and experiments are combined to demonstrate a novel protective layer to cope with the Li 6 PS 5 Cl electrolyte and LiCoO 2 cathode interface problem. By uniformly coating LiCoO 2 with a layer of Li 2 WO 4 , the interfacial resistance (the 100th cycle) between the sulfide electrolyte and LiCoO 2 is reduced to about 68 Ω cm 2 , which is nearly 15 times lower than the premodified 1061 Ω cm 2 . The 2 wt% Li 2 WO 4 -coated LiCoO 2 (2%LWO-LCO)/Li 6 PS 5 Cl/Li-In all-solid-state battery exhibits satisfactory capacity and excellent cycling stability at room temperature (93% capacity retention after 100 cycles). Furthermore, the ab initio molecular dynamics based on the Perdew, Burke, and Ernzerhof density functional theory calculations show that Li 2 WO 4 can effectively prevent the diffusion of Co and O from LiCoO 2 into the Li 6 PS 5 Cl solid electrolyte. It is shown that molecular dynamics help predict the interfacial reactions in all-solid-state sulfide batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ao Zhou,Dan Zhang,Zhihong Liu,Zhiyong Liu
With the retirement of rechargeable lithium-ion batteries (LIBs) entering peak period, the recycling of LiCoO 2 has become a hot topic. The spent LiCoO 2 batteries are rich in carcinogenic metal Co and high-value metal Li, so they are needed to be recovered in time before causing serious environmental pollution and resource waste. Thus, a clean and efficient process is proposed for the comprehensive recovery of Li, Co, and Mn from the spent LiCoO 2 cathode material. It is an integrated pyro-hydrometallurgical process, mainly consisting of sulfation roasting with NH 4 HSO 4 and selective sulfurizing leaching with (NH 4 ) 2 S solution. Using low melting point ammonium salt as roasting auxiliary, 99.7 %, 99.1 %, and 99.8 % of Li, Co, and Mn in the spent LiCoO 2 powder can be converted into sulfate when roasting under 400 ℃ for 75 min. Then 99.5 % of Li in the sulfation roasting product can be selectively leached with an aqueous (NH 4 ) 2 S solution, which is also a precipitator for Co, Mn, and impurity Al. In addition, 96.4 % of Co and 96.0 % of Mn in the sulfurized precipitate can be separated with impurity elements Al and C via oxidation roasting–water leaching process. Compared to traditional recycling, this method can achieve a higher Li leaching rate at a low roasting temperature, and the recovery of Co and Mn can be realized without adding any acid/base reagents or impurity cations. More importantly, the circulation of NH 3 /NH 4 + and S element in the recycling system has been taken into account, making it an environmental-friendly and economical process. In this study, the sulfation reduction roasting and selective sulfurizing leaching mechanisms were both revealed in details, and the behavior of the valuable elements was also elucidated.
研究领域:
环境科学
·
冶金工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）