Journal of Energy Storage
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2024
·
IF 8.9
Mengna Shi,Tie Ma,Chenqi Wang,Changcheng Liu,Que Huang,Li Guo,Dan Li
The thermal stability of lithiated graphite plays an important role in the thermal safety of lithium-ion batteries (LIBs). However, a safer graphite anode usually leads to a lower energy density. This article starts from multiple hazardous factors of lithiated graphite when thermal runaway occurs, considering the impact of defects on the electrochemical performance and thermal safety of graphite electrodes. In this study, turbostratic graphite was prepared as the anode for LIBs. The stacking of graphite was altered to form narrow pores and spherical aggregates, and introducing defects. By varying the ball-milling time, the structural changes of different ball-milled graphites were analyzed. The impact mechanism of defect structure on electrode electrochemical performance and safety performance was investigated. The results show that the spherical structure and large specific surface area are beneficial to increase the active sites and delay the self-heating of the battery. The formation of defects and pores increases the adsorption sites, which makes the surface adsorption of Li + dominant and improves the ion diffusion. In addition, the dominance of surface adsorption and desorption effectively suppresses the problem of graphite flake peeling and intensified thermal runaway caused by graphite phase transition and lithium evolution heat release at high temperature. The thermal safety test was carried out by accelerated calorimeter (ARC), and its thermodynamics and reaction kinetics were quantitatively analyzed. It was proved that the introduction of surface adsorption lithium storage method successfully delayed the thermal runaway of the battery, realizing the balance between high electrochemical performance and high safety.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
·
2018
·
IF 0
Longlu Wang,Qingfeng Zhang,Jingyi Zhu,Xidong Duan,Zhi Xu,Yutang Liu,Hongguan Yang,Bingan Lu
Two-dimensional (2D) layered transition metal sulfide based materials are promising candidates for electrodes of lithium ion batteries (LIBs). As one of the representatives, molybdenum disulfide (MoS 2 ), exhibits additional reversible capacity beyond their theoretical value although the lithium storage mechanism is still poorly understood. In this report, we developed a highly conducting metallic phase 1T(octahedral)-MoS 2 based electrode with metal Mo atoms confined in “graphene nanoreactor” of abnormal lithium-storage sites, which delivered a high specific capacity of ~1800 mAh g −1 at 1 A g -1 , about 2.6 times of its intercalation reactions value. Contrary to previous reports, a new lithium-storage mechanism for the high and ever-increasing capacity was proposed. The theoretical calculations and experiments show that a major contribution to the extra capacity in MoS 2 anodes is due to Mo atoms accommodate with Li + . The Mo precipitates and their full contact with Li 2 S matrix enabled the reversible Mo→Li x Mo→Mo→1T-MoS 2 reaction during charging/discharging processes. Over prolonged cycling, per Mo atomic could accommodate six Li + ions. This new proposal could help to establish an accurate electrochemical reaction mechanism of MoS 2 LIBs, which may lead to inspiration on new methods to greatly improve the performance of the MoS 2 anode.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Jie Shu,Kaiqiang Wu,Pengfei Wang,Peng Li,Xiaoting Lin,Lianyi Shao,Miao Shui,Nengbing Long,Dongjie Wang
Na 2 Li 2 Ti 6 O 14 is synthesized by a simple solid state method between 500 and 900 °C. It is found that pure Na 2 Li 2 Ti 6 O 14 is only formed at 800 °C or above. The tap density of as-prepared Na 2 Li 2 Ti 6 O 14 is about 1.52 g cm −3 . Particle morphology analysis shows that the size of Na 2 Li 2 Ti 6 O 14 gradually increases with the increase of sintering temperature. Calcined at 900 °C, Na 2 Li 2 Ti 6 O 14 shows slight particle aggregation and melting. As a result, Na 2 Li 2 Ti 6 O 14 formed at 800 °C reveals higher electrochemical activity than the sample obtained at 900 °C. Therefore, the suitable preparation temperature for Na 2 Li 2 Ti 6 O 14 by solid state reaction is 800 °C. Charge–discharge results show that Na 2 Li 2 Ti 6 O 14 prepared at 800 °C can deliver a reversible capacity of 89.9 mAh g −1 at 100 mA g −1 , 81.3 mAh g −1 at 200 mA g −1 , 75.2 mAh g −1 at 300 mA g −1 , 69.6 mAh g −1 at 400 mA g −1 and 65.5 mAh g −1 at 500 mA g −1 . Besides, the lithium storage mechanism in Na 2 Li 2 Ti 6 O 14 is also studied by various in-situ and ex-situ methods, which prove that the structural evolution is highly reversible for Na 2 Li 2 Ti 6 O 14 during lithiation/delithiation process.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Dong Zeng,Heng Xiong,Lu Wu,Yuexing Zhang,Kai Qi,Xingpeng Guo,Yubing Qiu
Graphite microcrystalline carbon (GMC) is a potential candidate for lithium storage devices because of its high degree of disorder in the crystalline structure. The mechanism that affects the energy-storage ability of GMC in its capacitive coupling state is still unclear. Herein, high-energy GMC is synthesized through a dual-activation approach, and its kinetics and lithium-storage mechanism to boost lithium-ion diffusion are further investigated. The porous graphite microcrystalline provides the structural advantage in raising the Li + storage capability, promotes the rapid transfer of electrons/ions, and possesses high conductivity. The defective heterostructure stimulates the internal electric field effect, facilitating rapid charge convey and fast diffusion kinetics. The first-principles calculations reveal that the nitrogen vacancies generated in graphite crystallites provide abundant reactive sites and induce excessive electrons around the local nitrogen atoms to form negative charge centers for accelerating the conveyance of Li + . The GMC electrode displays a high capacity of 1195 mAh g −1 at 0.1 A g −1 , while the assembled GMC//GMC lithium-ion capacitor device delivers a high energy density of 190.63 Wh kg −1 at 225 W kg −1 . This work is expected to offer an in-depth mechanism of electrons/ions diffusion and lithium storage for high-energy carbon electrodes and provide rational ideas for the optimal construction of high-energy carbon-based materials.
研究领域:
材料科学
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能源存储
·
计算材料学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2022
·
IF 18.027
Yingnan Cao,Weiwei Sun,Chaofei Guo,Lu Zheng,Mengyao Yao,Yong Wang
Covalent organic polymers are attracting more and more attention for energy storage devices due to their lightweight, molecular viable design, stable structure, and environmental benignity. However, low charge-carrier mobility of pristine covalent organic materials is the main drawback for their application in lithium-ion batteries. Herein, a yolk–shell bimetal-modified quinonyl-rich covalent organic material, Co@2AQ-MnO2, has been designed and synthesized by in situ loading of petal-like nanosized MnO2 and coordinating with Co centers, with the aim to improve the charge conductivity of the covalent organic polymer and activate its Li-storage sites. As investigated by in situ FT-IR, ex situ XPS, and electrochemical probing, the quinonyl-rich structure provides abundant redox sites (carbonyl groups and π electrons from the benzene ring) for lithium reaction, and the introduction of two types of metallic species promotes the charge transfer and facilitates more efficient usage of active energy-storage sites in Co@2AQ-MnO2. Thus, the Co@2AQ-MnO2 electrode exhibits good cycling performance with large reversible capacity and excellent rate performance (1534.4 mA h g–1 after 200 cycles at 100 mA g–1 and 596.0 mA h g–1 after 1000 cycles at 1000 mA g–1).
研究领域:
材料科学
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能源存储
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电化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Yang Chen,Ye Li,Xiaohuan Wang,Huijun Kang,Zhiming Shi,Guojun Ji,Zhipeng Yuan
Constructing heterojunctions is an effective strategy for improving the migration of electronic charge carriers and enhancing electronic conductivity. Herein, polyvinylpyrrolidone crosslinked with graphene oxide was used as a template to construct a FeTiO3@Fe2TiO5 endogenous heterojunction anode material (hetero-FTO) anode. The initial electrochemical capacity of the hetero-FTO anode (1207 mA h g−1 at 100 mA g−1) was approximately twice that of FTO (600 mA h g−1 at 100 mA g−1). Electrochemical kinetics and density functional theory calculations demonstrated that the built-in electric field formed at the interface of the endogenous heterojunction increased the electronic conductivity and effectively improved the conversion rate. The structural evolution of the heterojunction during cycling was tracked using in situ XPS and ex situ HRTEM and calculation of Gibbs free energies. After 100 cycles, the FeTiO3@Fe2TiO5 heterojunction structures transformed into cubic phase γ-Fe2O3; however, the capacity still increased to 865 mA h g−1. This ingenious heterogeneous-structure-design strategy and analysis of the heterogeneous structural evolution are crucial for improving the lithium-storage performance of batteries, especially those containing titanium-based conversion-type anode materials.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2014
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IF 5.211
Xinxin Jiang,Kaiqiang Wu,Lianyi Shao,Miao Shui,Xiaoting Lin,Mengmeng Lao,Nengbing Long,Yuanlong Ren,Jie Shu
Copper nitrate hydrate (Cu(NO 3 ) 2 ·2.5H 2 O) exhibits superior high lithium storage capacity (2285 mAh g −1 ) as anode material for lithium-ion batteries. The structural transformation and lithium storage mechanism of Cu(NO 3 ) 2 ·2.5H 2 O are thoroughly studied by various advanced analytical techniques. It is found that the lithium storage process of Cu(NO 3 ) 2 ·2.5H 2 O is associated with a quasi-reversible electrochemical conversion reaction. During the discharge process, the electrochemical reaction of Cu(NO 3 ) 2 ·2.5H 2 O with lithium results in the formation of Cu, LiNO 3 , Li 3 N, Li 2 O and H 2 O. In the reverse charge process, Cu(NO 3 ) 2 can be generated by a conversion reaction. As a result, Cu(NO 3 ) 2 ·2.5H 2 O shows the reversible charge capacities of 1632.1 mAh g −1 in 0.0–3.4 V and 689.1 mAh g −1 in 1.0–3.4 V, respectively.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 24
·8744-8752
·
IF 8.307
Xiaoge Mao,Kuan Wu,Shang-Qi Li,Fei-Hu Du,Gang Xu,Minghong Wu,Hua-Kun Liu,Shi-Xue Dou,Chao Wu
Phosphorus-rich iron phosphides (FeP2) have been regarded as excellent anode candidates for lithium storage owing to their low cost, high natural abundance, high theoretical capacity, and reasonable redox potential. However, FeP2 suffers from a few challenging problems such as low reversibility, fast capacity degradation, and big volume variation. Herein, we have designed and synthesized a 3D honeycomb-like carbon skeleton with embedded FeP2 nanoparticles (denoted as FeP2 NPs@CK), which can significantly promote the kinetics and maintain the structural stability during the cycling, resulting in an excellent electrochemical performance reflected by high reversibility and long-term cycling stability. FeP2 NPs@CK shows high reversibility, delivering a reversible capacity as high as 938 mA h g−1 at 0.5 A g−1. It also shows excellent cycling stability, delivering a capacity of 620 mA h g−1 after 500 cycles at 1 A g−1. Moreover, the fast kinetics and lithium storage mechanism of FeP2 NPs@CK are investigated by quantitative analysis and in situ X-ray diffraction. Such superior performance demonstrates that FeP2 NPs@CK could be a promising and attractive anode candidate for lithium storage.
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
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Zhenbang Li,Dongpeng Yu,Junjie Xie,Fei Tian,Danni Lei,Chengxin Wang
At present, graphite is a widely used anode material in commercial lithium-ion batteries for its low cost, but the large volume expansion (about 10%) after fully lithiated makes the material prone to cracking and even surface stripping in the cycle. Therefore, the development of zero-strain anode materials (volume change <1%) is of great significance. LiAl5O8 is a zero-strain insertion anode material with a high theoretical specific capacity. However, the Li+ storage mechanism remains unclear, and the cycle life as well as fast-charging capability need to be greatly improved to meet the practical requirements. In this study, LiAl5O8 nanorods are prepared by utilizing aluminum ethoxide nanowires as a soft template and doped with the Zr element to further improve the Li+ diffusion coefficient and electronic conductivity, which in turn improves cycle and rate performances. The Zr-doped LiAl5O8 presents a high reversible capacity of 227.2 mAh g–1 after 20,000 cycles under 5 A g–1, which significantly outperforms the state-of-the-art anode materials. In addition, the Li+ storage mechanisms of LiAl5O8 and Zr-doped LiAl5O8 are clearly clarified with a variety of characterization techniques including nuclear magnetic resonance. This work greatly promotes the practical process of zero-strain insertion anode materials.
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
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 29
·18393-18403
·
IF 10.7
Fengjie Zhang,Wenhao Fang,Xiangkun Wu,Xingmei Lu
Currently, addressing the challenges posed by the low energy density of lithium titanate (LTO), a prevalent anode material in lithium slurry batteries (LSBs), is crucial for ensuring high stability, storage capacity, and cycle stability, thereby facilitating the commercialization of LSBs. In this study, a heterostructure (LTO-TOB) was created by integrating nano-TiO2(B) (bronze phase) onto the surface of commercial LTO. The coated TiO2(B) layer significantly increases the specific surface area and wettability, guaranteeing fantastic stability. The pseudo-capacitance lithium storage ability of TiO2(B) boosts the power of the electrochemical reaction. The extra interface in the crystalline phase and the presence of oxygen vacancies serve not just as lithium storage sites, but also accelerate the Li+ diffusivity and enhance the electron conductivity. Furthermore, the diffusion mechanism of lithium ions within LTO-TOB anolyte was examined by using a designed in situ Raman cell. The engineered LTO-TOB anolyte assembled reactor boasts a substantial specific capacity of 209.12 mA h g−1 at 0.5C, coupled with remarkable cycle steadiness (with a mere 0.095% capacity loss per 100 cycles). The reactor exhibits favorable electrochemical characteristics in both intermittent mode and static long-term cyclic mode, thereby highlighting the significance of surface heterostructure modification as a key approach in advancing the progress of LSBs.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）