scholarly journals Supercooled liquid sulfur maintained in three-dimensional current collector for high-performance Li-S batteries

2020 ◽  
Vol 6 (21) ◽  
pp. eaay5098 ◽  
Author(s):  
Guangmin Zhou ◽  
Ankun Yang ◽  
Guoping Gao ◽  
Xiaoyun Yu ◽  
Jinwei Xu ◽  
...  

In lithium-sulfur (Li-S) chemistry, the electrically/ionically insulating nature of sulfur and Li2S leads to sluggish electron/ion transfer kinetics for sulfur species conversion. Sulfur and Li2S are recognized as solid at room temperature, and solid-liquid phase transitions are the limiting steps in Li-S batteries. Here, we visualize the distinct sulfur growth behaviors on Al, carbon, Ni current collectors and demonstrate that (i) liquid sulfur generated on Ni provides higher reversible capacity, faster kinetics, and better cycling life compared to solid sulfur; and (ii) Ni facilitates the phase transition (e.g., Li2S decomposition). Accordingly, light-weight, 3D Ni-based current collector is designed to control the deposition and catalytic conversion of sulfur species toward high-performance Li-S batteries. This work provides insights on the critical role of the current collector in determining the physical state of sulfur and elucidates the correlation between sulfur state and battery performance, which will advance electrode designs in high-energy Li-S batteries.

2021 ◽  
Vol 22 (20) ◽  
pp. 11041
Author(s):  
Yajing Yan ◽  
Yanxu Chen ◽  
Yongyan Li ◽  
Xiaoyu Wu ◽  
Chao Jin ◽  
...  

By virtue of the high theoretical capacity of Si, Si-related materials have been developed as promising anode candidates for high-energy-density batteries. During repeated charge/discharge cycling, however, severe volumetric variation induces the pulverization and peeling of active components, causing rapid capacity decay and even development stagnation in high-capacity batteries. In this study, the Si/Fe2O3-anchored rGO framework was prepared by introducing ball milling into a melt spinning and dealloying process. As the Li-ion battery (LIB) anode, it presents a high reversible capacity of 1744.5 mAh g−1 at 200 mA g−1 after 200 cycles and 889.4 mAh g−1 at 5 A g−1 after 500 cycles. The outstanding electrochemical performance is due to the three-dimensional cross-linked porous framework with a high specific surface area, which is helpful to the transmission of ions and electrons. Moreover, with the cooperation of rGO, the volume expansion of Si is effectively alleviated, thus improving cycling stability. The work provides insights for the design and preparation of Si-based materials for high-performance LIB applications.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Hanwen Liu ◽  
Wei-Hong Lai ◽  
Qiuran Yang ◽  
Yaojie Lei ◽  
Can Wu ◽  
...  

Abstract This work reports influence of two different electrolytes, carbonate ester and ether electrolytes, on the sulfur redox reactions in room-temperature Na–S batteries. Two sulfur cathodes with different S loading ratio and status are investigated. A sulfur-rich composite with most sulfur dispersed on the surface of a carbon host can realize a high loading ratio (72% S). In contrast, a confined sulfur sample can encapsulate S into the pores of the carbon host with a low loading ratio (44% S). In carbonate ester electrolyte, only the sulfur trapped in porous structures is active via ‘solid–solid’ behavior during cycling. The S cathode with high surface sulfur shows poor reversible capacity because of the severe side reactions between the surface polysulfides and the carbonate ester solvents. To improve the capacity of the sulfur-rich cathode, ether electrolyte with NaNO3 additive is explored to realize a ‘solid–liquid’ sulfur redox process and confine the shuttle effect of the dissolved polysulfides. As a result, the sulfur-rich cathode achieved high reversible capacity (483 mAh g−1), corresponding to a specific energy of 362 Wh kg−1 after 200 cycles, shedding light on the use of ether electrolyte for high-loading sulfur cathode.


2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Jing Ning ◽  
Maoyang Xia ◽  
Dong Wang ◽  
Xin Feng ◽  
Hong Zhou ◽  
...  

Abstract Recent developments in the synthesis of graphene-based structures focus on continuous improvement of porous nanostructures, doping of thin films, and mechanisms for the construction of three-dimensional architectures. Herein, we synthesize creeper-like Ni3Si2/NiOOH/graphene nanostructures via low-pressure all-solid melting-reconstruction chemical vapor deposition. In a carbon-rich atmosphere, high-energy atoms bombard the Ni and Si surface, and reduce the free energy in the thermodynamic equilibrium of solid Ni–Si particles, considerably catalyzing the growth of Ni–Si nanocrystals. By controlling the carbon source content, a Ni3Si2 single crystal with high crystallinity and good homogeneity is stably synthesized. Electrochemical measurements indicate that the nanostructures exhibit an ultrahigh specific capacity of 835.3 C g−1 (1193.28 F g−1) at 1 A g−1; when integrated as an all-solid-state supercapacitor, it provides a remarkable energy density as high as 25.9 Wh kg−1 at 750 W kg−1, which can be attributed to the free-standing Ni3Si2/graphene skeleton providing a large specific area and NiOOH inhibits insulation on the electrode surface in an alkaline solution, thereby accelerating the electron exchange rate. The growth of the high-performance composite nanostructure is simple and controllable, enabling the large-scale production and application of microenergy storage devices.


2018 ◽  
Vol 6 (4) ◽  
pp. 1802-1808 ◽  
Author(s):  
Ke Li ◽  
Yanshan Huang ◽  
Jingjing Liu ◽  
Mansoor Sarfraz ◽  
Phillips O. Agboola ◽  
...  

Three-dimensional graphene frameworks enable the development of stretchable asymmetric supercapacitors with a record high energy density of 77.8 W h kg−1, and also excellent stretchability and superior cycling stability.


2010 ◽  
Vol 25 (8) ◽  
pp. 1485-1491 ◽  
Author(s):  
Emilie Perre ◽  
Pierre Louis Taberna ◽  
Driss Mazouzi ◽  
Philippe Poizot ◽  
Torbjörn Gustafsson ◽  
...  

An increasing demand on high energy and power systems has arisen not only with the development of electric vehicle (EV), hybrid electric vehicle (HEV), telecom, and mobile technologies, but also for specific applications such as powering of microelectronic systems. To power those microdevices, an extra variable is added to the equation: a limited footprint area. Three-dimensional (3D) microbatteries are a solution to combine high-density energy and power. In this work, we present the formation of Cu2Sb onto three-dimensionally architectured arrays of Cu current collectors. Sb electrodeposition conditions and annealing post treatment are discussed in light of their influence on the morphology and battery performances. An increase of cycling stability was observed when Sb was fully alloyed with the Cu current collector. A subsequent separator layer was added to the 3D electrode when optimized. Equivalent capacity values are measured for at least 20 cycles. Work is currently devoted to the identification of the causes of capacity fading.


2016 ◽  
Vol 4 (43) ◽  
pp. 16879-16885 ◽  
Author(s):  
Ya Wang ◽  
Hui Dou ◽  
Bing Ding ◽  
Jie Wang ◽  
Zhi Chang ◽  
...  

A symmetric capacitor based on facilely synthesized three-dimensional oriented porous carbon nanosheets delivers high energy density.


Nanoscale ◽  
2019 ◽  
Vol 11 (28) ◽  
pp. 13639-13649 ◽  
Author(s):  
Pengxi Li ◽  
Chaohui Ruan ◽  
Jing Xu ◽  
Yibing Xie

A three-dimensional criss-crossed ZnMoO4/CoO nanohybrid was synthesized to deliver high energy storage performance.


Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 695 ◽  
Author(s):  
Yijun Liu ◽  
Ying He ◽  
Elif Vargun ◽  
Tomas Plachy ◽  
Petr Saha ◽  
...  

To improve Li storage capacity and the structural stability of Ti3C2 MXene-based electrode materials for lithium-ion batteries (LIBs), a facile strategy is developed to construct three-dimensional (3D) hierarchical porous Ti3C2/bimetal-organic framework (NiCo-MOF) nanoarchitectures as anodes for high-performance LIBs. 2D Ti3C2 nanosheets are coupled with NiCo-MOF nanoflakes induced by hydrogen bonds to form 3D Ti3C2/NiCo-MOF composite films through vacuum-assisted filtration technology. The morphology and electrochemical properties of Ti3C2/NiCo-MOF are influenced by the mass ratio of MOF to Ti3C2. Owing to the interconnected porous structures with a high specific surface area, rapid charge transfer process, and Li+ diffusion rate, the Ti3C2/NiCo-MOF-0.4 electrode delivers a high reversible capacity of 402 mAh g−1 at 0.1 A g−1 after 300 cycles; excellent rate performance (256 mAh g−1 at 1 A g−1); and long-term stability with a capacity retention of 85.7% even after 400 cycles at a high current density, much higher than pristine Ti3C2 MXene. The results highlight that Ti3C2/NiCo-MOF have great potential in the development of high-performance energy storage devices.


Sign in / Sign up

Export Citation Format

Share Document