ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Chun-xian Zhou,Peng-bo Wang,Bao Zhang,Lin-bo Tang,Hui Tong,Zhen-jiang He,Jun-chao Zheng
Li-rich cathode materials are regarded as ideal cathode materials, owing to their excellent electrochemical capacity. However, residual lithium compounds, which are formed on the surface of the materials by reacting with moisture and carbon dioxide in ambient atmosphere, can impair the surface structure, injure the capacity, and impede the electrode fabrication using Li-rich materials. Exposure to air atmosphere causes the formation of residual lithium compounds; the formation of such compounds is believed to be related to humidity, temperature, and time during handling and storage. In this study, we demonstrated for the first time an artificial strategy for controlling time, temperature, and humidity to accelerate exposure. The formation and effect of residual lithium compounds on Li-rich cathode material Li1.35[Ni0.35Mn0.65]O2 were systematically investigated. The residual lithium compounds formed possessed primarily an amorphous structure and were partially coated on the surface. These compounds include LiOH, Li2O, and Li2CO3. Li2CO3 is the major component in residual lithium compounds. The presence of residual lithium compounds on the material surface led to a high discharge capacity loss and large discharge voltage fading. Understanding the formation and suppressing the effect of residual lithium compounds will help prevent their unfavorable effects and improve the electrochemical performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Hualong Wu,Jiahao Dong,Jiantao Li,Guiyang Gao,Liang Lin,Ailin Liu,Hongfei Zheng,Guanyi Wang,Junxiang Liu,Laisen Wang,Jie Lin,Khalil Amine,Dong-Liang Peng,Qingshui Xie,Jun Lu
Low initial Coulombic efficiency and severe capacity/voltage fading during cycling caused by serious irreversible oxygen release, especially in the initial cycle, and resultantly induced unstable electrode/electrolyte interfacial chemistry, largely prohibit the commercial application of high-capacity Li-rich layered oxide cathodes (LLOs). In this work, a dual reductive gas interface cotreatment strategy is applied to regulate the lattice oxygen redox activity and reversibility with a multiple defective structure design including Li/O/TM (TM = transition metal) vacancies and the intrinsic TM doping as well as a full-surface protective layer, which can suppress the irreversible TM migration and then undesirable phase transformation, resisting the corrosion of electrolyte during cycling effectively. Importantly, the introduced reversible SO32–/SO42– redox couple that provides extra capacity compensation could alleviate the distortion of oxygen-central octahedral structure and structural collapse caused by immoderate oxygen oxidation. Thus, the lattice oxygen redox chemistry is optimized, with negligible oxygen loss during the initial cycle. And the designed AS-LLO cathode with greatly enhanced structure stability shows high-capacity retentions of 99.2% at 0.3C after 100 cycles and 82.4% even after 1000 cycles at 5C. This work provides a guideline for manipulating the oxygen redox chemistry to achieve long-lifespan Li-rich layered oxide cathodes for high-energy-density lithium batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Ao Li,Can Qian,Guihong Mao,Zhao Liu,Zhixiong Li,Yujia Zhang,Liang Yin,Laifa Shen,Hong Li
Lithium-rich layered oxides (LROs) possess enormous potential in the new generation of high-energy lithium-ion batteries due to their high specific capacity, working voltage, and low cost. However, they still face low initial coulombic efficiency, poor cycling stability and multiplication performance, and persistent voltage decay, which seriously hinder their development in the lithium-ion battery industry. In this article, the Li 1·4 Y 0·4 Ti 1·6 (PO 4 ) 3 ionic conductive layer is constructed on the surface of LROs using surface residuals as lithium sources. Such a one-step modification method not only improves the rate performance of LROs by enhanced kinetic property of Li + , but also elongates the cycling lives at high-temp and high-rates by the inhibition of interfacial side reactions. As a result, the LRO cathode with a high initial coulombic efficiency of 89.3% and a good capacity retention of 83.2% after 200 cycles at 1C is obtained. It is noteworthy that this multifunctional surface modification strategy can stimulate the potential of LROs in lithium-ion batteries and provide a new way to stabilize their structure.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Small Methods
·
2022
·Vol. 6
·期 7
·2200449
·
IF 15.367
Junhua Zhou,Zhujie Chen,Guo Yu,Keni Ma,Xueyu Lian,Shuo Li,Qitao Shi,Jiaqi Wang,Lingli Guo,Yu Liu,Alicja Bachmatiuk,Jingyu Sun,Ruizhi Yang,Jin-Ho Choi,Mark H. Rümmeli
Lithium-rich cathodes (LRCs) show great potential to improve the energy density of commercial lithium-ion batteries owing to their cationic and anionic redox characteristics. Herein, a complete conductive network using carbon nanotubes (CNTs) additives to improve the poor kinetics of LRCs is fabricated. Ex situ X-ray photoelectron spectroscopy first demonstrates that the slope at a low potential and the following long platform can be assigned to the transition metal and oxygen redox, respectively. The combination of galvanostatic intermittent titration technique and electrochemical impedance spectroscopy further reveal that a battery with CNTs exhibited accelerated kinetics, especially for the O-redox process. Consequently, LRCs with CNTs exhibit a much better rate and cycling performance (≈89% capacity retention at 2 C for over 200 cycles) than the Super P case. Eventually, TEM results imply that the improved electrochemical performance of the CNTs case also benefits from its more stable bulk and surface structures. Such a facile conductive additive modification strategy also provides a universal approach for the enhancement of the electron diffusion properties of other electrode materials.
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
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Chen Hou,Yi-Ran Xing,Le-Le Yu,Yong-Heng Si,Han Lu,Yu-Juan Zhao
Fe–Mn based Li-rich cathode materials are regarded as one of the most promising cathode materials for their low cost and high energy density but possess drawbacks such as high oxygen release, low conductivity, and slow kinetics for lithium-ion transport. To address these issues, herein, we proposed a high-valance cations Nb 5+ doping strategy and synthesized a series of Li 1.26 [Fe 0.22 Mn 0.52 ] 1−x Nb 0.74x O 2 ( x = 0, 0.02, 0.03, 0.04) cathode materials. Using a combination of experimental approaches and density functional theory (DFT) calculations, we found that the doped samples presented expanded interlayer spacing for Li-ion migration and better structural stability due to the large ionic radius of Nb 5+ and the strengthened Nb–O bond. Moreover, Nb doping could not only decrease the band gap and the density of states of the O 2p band but also contribute extra electrons to surrounding O atoms, thereby enhancing electronic conductivity and stabilizing lattice oxygen. Benefit from the underlying mechanisms mentioned above, the Nb 0.022 sample possessed a higher Coulombic efficiency (71.1 vs 65.0%) at 0.2 C, showing more stable cycling performance (90.4 vs 67.7 mAh g −1 ) at 0.5 C and rate capability. These favorable results can assist in the development of Fe–Mn based Li-rich cathode materials with excellent electrochemical properties.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2022
·Vol. 15
·期 2
·588-598
·
IF 8.307
Zhenbo Wang,Yanfeng Yin,Guanjie He,Huiling Zhao,Ying Bai
With large specific capacity, wide voltage window, and high energy density, Li-rich layered oxides have been considered as a promising cathode candidate for advanced lithium-ion batteries (LIBs). However, their commercial application is challenging due to severe capacity degradation and voltage fading caused by irreversible oxygen evolution and phase transition upon repeated cycling. This work proposes an effective strategy to improve the long-term electrochemical performances of Li1.2Mn0.56Ni0.17Co0.07O2 (LMNCO) by constructing multifunctional nanolayers composed of element-doping, layered-spinel heterostructural connection, and fast ion conductor shell via a facile method. The Li0.09B0.97PO4 (LBPO) coating shell acts as a fast ion carrier and physical screen to promote Li+ diffusion and isolate side reactions at the cathode-electrolyte interface; moreover, two-phase transitional region provides three-dimensional channel to facilitate Li+ transport and inhibit phase transition. Besides, B3+ and PO43−-doping collaborates with oxygen vacancies to stabilize lattice oxygen and restrain oxygen evolution from the bulk active cathode. The optimized LMNCO@LBPO material exhibits a superior capacity retention of 78.6%, higher than that of the pristine sample (49.3%), with the mitigated voltage fading of 0.73 mV per cycle after 500 cycles at 1 C. This study opens up an avenue for the surface modification to the electrochemical properties and perspective application of Li-rich cathodes in high-performance LIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energy Technology
·
2018
·Vol. 7
·期 8
·1800829
·
IF 3.175
Bin Xiao,Peng-bo Wang,Zhen-jiang He,Zhuo Yang,Lin-bo Tang,Chang-sheng An,Jun-chao Zheng
0.5Li 2 MnO 3 ·0.5LiNi 0.5 Mn 0.3 Co 0.2 O 2 cathode materials with nano-MgO and nano-TiO 2 coating layers are synthesized via a facile approach. These nanocoating layers with a thickness of ≈20 nm are homogeneously coated on the surface of the materials. With the nano-MgO and nano-TiO 2 coating layers, the modified materials deliver excellent electrochemical performance. Nano-MgO-coated and nano-TiO 2 -coated Li-rich materials exhibit 147.56 and 137.96 mAh g −1 after 100 cycles at 1C rate and deliver 156.13 and 130.69 mAh g −1 at 2C rate, respectively, in the voltage range of 2.0–4.8 V. The materials with nano-MgO and nano-TiO 2 coating layers also show a high discharge voltage retention of more than 90% after 50 cycles, low impedance for Li + migration, and high diffusion coefficients of the lithium ions. Nano-MgO and nano-TiO 2 coating layers help decrease the content of Li 2 CO 3 on the surface of the materials and suppress side reactions. Thus, these materials play a significant role in strengthening the electrochemical performance of Li-rich cathode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Bo Cao,Yiwei Li,Mingjian Zhang,Ningyan Cheng,Ming Shen,Bingwen Hu,Jianyuan Li,Zhibo Li,Shenyang Xu,Wenguang Zhao,Ni Yang,Junliang Sun,Shixue Dou,Yang Ren,Haibiao Chen,Liang Yin,Feng Pan
In the practical operations of Li-ion batteries , inevitable deep charge/discharge happens locally due to the intrinsic (de)lithiation inhomogeneity at the electrode and particle level, which would damage the health of batteries and even cause the safety concern. It is essential to develop the stable cathodes operating in a wide voltage window to ensure the health and safety of Li-ion batteries. Herein, we comprehensively investigate the charge/discharge behaviors of a representative Li-rich cathode Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 in a wide voltage window of 1.0–4.8 V, and reveal that, deep-lithiation would drive violent TM migration and severe Li/TM mixing, thereby leading to the irreversible structural transformation from layered to spinel then to rock salt, eventually causing the fast decay in electrochemical performance. Based on these understandings, a novel Li-rich cathode Li[Li 1/4 Mn 1/2 Ni 1/6 Sb 1/12 ]O 2 is successfully synthesized through introducing aromatic Sb@Ni 6 superstructure units in the TM layers. The introduced Sb@Ni 6 superstructure units can effectively tune the local oxygen environment, suppress TM migration, and stabilize the layered framework under deep lithiation . Finally, a stable charge/discharge is achieved in 1.0–4.8 V. This work deepens the understanding into the structural stability of Li-rich cathodes in a wide voltage window, and benefits the development of high-energy-density and safe cathodes.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2019
·Vol. 7
·期 3
·1902538
·
IF 15.804
Mengting Si,Dandan Wang,Rui Zhao,Du Pan,Chen Zhang,Caiyan Yu,Xia Lu,Huiling Zhao,Ying Bai
As one of the most promising cathodes for next-generation lithium ion batteries (LIBs), Li-rich materials have been extensively investigated for their high energy densities. However, the practical application of Li-rich cathodes is extremely retarded by the sluggish electrode–electrolyte interface kinetics and structure instability. In this context, piezoelectric LiTaO 3 is employed to functionalize the surface of Li 1.2 Ni 0.17 Mn 0.56 Co 0.07 O 2 (LNMCO), aiming to boost the interfacial Li + transport process in LIBs. The results demonstrate that the 2 wt% LiTaO 3 -LNMCO electrode exhibits a stable capacity of 209.2 mAh g −1 at 0.1 C after 200 cycles and 172.4 mAh g −1 at 3 C. Further investigation reveals that such superior electrochemical performances of the LiTaO 3 modified electrode results from the additional driving force from the piezoelectric LiTaO 3 layer in promoting Li + diffusion at the interface, as well as the stabilized bulk structure of LNMCO. The supplemented LiTaO 3 layer on the LNMCO surface herein, sheds new light on the development of better Li-rich cathodes toward high energy density applications.
研究领域:
材料科学
·
电化学
·
能源存储
·
功能材料
·
固态离子学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·Vol. 45
·期 8
·10633-10639
·
IF 3.45
Guorong Hu,Zhichen Xue,Zhongyuan Luo,Zhongdong Peng,Yanbing Cao,Weigang Wang,Yuexi Zeng,Yong Huang,Yong Tao,Tianfan Li,Zhiyong Zhang,Ke Du
The Li-rich cathode material for long cycle performance and long-term storage performance is a challenge for next-generation lithium-ion batteries due to the rapid capacity degradation over cycling and the formation of residual lithium on the surface during long-term storage. Herein, an elevated performance of Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 materials via CeO 2 inlay is reported, which was prepared from Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 by sol-gel inlay with CeO 2 . It was proved by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy that cerium oxide cladding not only covered the surface of the material but also diffused into the interior of the material change crystal structure. Cerium oxide on the cladding not only reduces the material's contact with water and carbon dioxide in the air, but also prevents the material from being corroded by electrolyte during electrochemical test. The position of the transition metal atom is replaced Ce atoms, which increases the unit cell volume and the stability of the Li-rich material during the cycling. The results show that the storage property and the electrochemical cycling property of the material have been improved obviously. The CeO 2 inlaid lithium rich material discharged 204.6 mAh/g for the first time at the current of 1C, and 164.4 mAh/g after 150 charge and discharge cycles with corresponding capacity retention rate of 80.35%, compared with the retention rate of 57.26% for pristine Li-rich material capacity. After being stored in humid air for 40 days, the CeO 2 inlaid lithium-rich material showed better electrochemical performance than the pristine one. It is powerfully demonstrated that the CeO 2 inlay strategy here holds huge promise for surface modification of electrode materials for lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
锂离子电池
·
能源存储
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Yi-Xuan Li,Xiang Ding,Fei Chen,Kuo Cao,Chun-Hua Chen
NaClO 4 is utilized as a salt-type electrolyte additive to improve the electrochemical performance in both Li-rich/graphite full cells and Li-rich/Li half cells. The corresponding characterizations such as scanning electron microscopy and X-ray photoelectron spectroscopy reveal that the NaClO 4 -added electrolyte can suppress the transition metal dissolution from Li-rich cathode and form a stable conductive cathode electrolyte interface layer to protect Li-rich cathode and promote Li + ions transfer. A small amount (0.1 wt%) of NaClO 4 additive enables Li-rich/graphite full cells to maintain 86% capacity after 50 cycles and Li-rich/Li half cells to maintain 95% capacity after 100 cycles, showing a great application potential.
研究领域:
电化学
·
材料科学
·
能源存储
·
电池技术
·
功能材料
✓ 已验证
DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 4
·3178-3186
·
IF 8.897
Liu Yanchen,Chen Yafen,Wang Jing,Wang Wei,Ding Zhiyu,Li Leyuan,Zhang Yang,Deng Yida,Wu Junwei,Chen Yanan
Despite the high energy density of lithium-rich (Li-rich) cathodes, their implementation is hampered by the unsatisfied rate capacity and poor cycling performance accompanied with substantial voltage decay. To address these issues, the hierarchical yolk-shell structured Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 cathodes (YK-LMNCO) was proposed and synthesized through a facile glycerol assisted solvothermal approach and the following lithiation process. Benefitting from the shortened lithium diffusion lengths and the enhanced tolerance to the large volume variation upon lithium ions intercalation/de-intercalation, the unique structure reciprocates an initial coulombic efficiency of 85.8%, an outstanding capacity retention rate of 89.1% after cycling at 2.0 C for 200 cycles with a minor voltage drop, and a capacity retention rate of 93.8% after cycling at 10.0 C for 500 cycles, 85.2% for 1,000 cycles. When assembled with graphite as anode, the YK-LMNCO//graphite full cell shows a remarkable capacity retention rate of 87.2% after cycling at 5.0 C for 50 cycles. Our facile strategy for constructing the yolk-shell structured Li-rich cathodes with high capacity and voltage stability sheds light on synthesizing other lithium storage materials.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
电池技术
·
固态化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）