Selenium Batteries Research Articles

Selenium Embedded in Metal-Organic Framework Derived Hollow Hierarchical Porous Carbon Spheres for Advanced Lithium-Selenium Batteries.

Metal-organic framework derived hollow hierarchical porous carbon spheres (MHPCS) have been fabricated via a facile hydrothermal method combined with a subsequent annealing treatment. Such MHPCS are composed of masses of small hollow carbon bubbles with a size of ∼20 nm and shells of ∼5 nm thickness interconnected to each other. MHPCS/Se composite is developed as a cathode for Li-Se cells and delivers an initial specific capacity up to 588.2 mA h g(-1) at a current density of 0.5 C, exhibiting an outstanding cycling stability over 500 cycles with a decay rate even down to 0.08% per cycle. This material is capable of retaining up to 200 mA h g(-1) even after 1000 cycles at a current density of 1 C. Such good electrochemical performance may be ascribed to the distinct hollow structure of the carbon spheres and a large amount of Se wrapped within small carbon bubbles, thus not only enhancing the electronic/ionic transport but also providing additional buffer space to adjust volume changes of Se during charge/discharge processes.

One-step microwave synthesized core-shell structured selenium@carbon spheres as cathode materials for rechargeable lithium batteries.

A core-shell structured selenium@carbon composite material was obtained by a facile one-step microwave synthesis method. The uniform carbon shells coated on selenium spheres greatly minimized the shuttle effect of Li-Se cells. The morphology analysis of the cathodes after different cycles revealed that the Se cores were perfectly confined inside the unbroken C shells all through the 100 cycles.

Strongly Bonded Selenium/Microporous Carbon Nanofibers Composite as a High-Performance Cathode for Lithium–Selenium Batteries

Although lithium–selenium batteries have attracted significant attention for high-energy-density energy storage systems due to their high volumetric capacity, their implementation has been hampered by the dissolution of polyselenide intermediates into electrolyte. Herein, we report a novel selenium/microporous carbon nanofiber composite as a high-performance cathode for lithium–selenium batteries through binding selenium in microporous carbon nanofibers. Under vacuum and heat treatment, selenium particles are easily transformed into chainlike Sen molecules that chemically bond with the inner surfaces of microporous carbon nanofibers. This chemical bonding can not only promote robust and intimate contact between selenium and carbonaceous nanofiber matrix but also alleviate the active material dissolution during cycling. Moreover, selenium is homogeneously distributed in the micropores of the highly conductive carbonaceous nanofiber matrix, which is favorable for the fast diffusions of both lithium ions and...

Reduced graphene oxide encapsulated selenium nanoparticles for high-power lithium–selenium battery cathode

Selenium nanoparticles are encapsulated uniformly with reduced graphene oxide (Se@RGO) by a simple self-assembly process. The Se@RGO composite has as high as 80 wt% of Se, which is much larger than that of other selenium-based cathode materials. The Se@RGO cathode delivers high capacity and rate capability in a Li–Se battery because of the large capacity of Se, highly dispersed Se nanoparticles in the RGO framework and high conductivity of Se and RGO nanocomposite cathode. A large initial discharge capacity of 533 mAh g−1 at 0.2C was produced based on the total mass of Se@RGO nanocomposites and the capacity could remain at 265 mAh g−1 after 200 cycles at 0.2C and additional 300 cycles at 1C. The electrode also shows an excellent capacity of 250 mAh g−1 at 5C (∼3.4 A g−1). The superior electrochemical performance suggests that the Se@RGO composite is a promising cathode in high-energy and high-power Li–Se battery.

Solution-based synthesis of multi-walled carbon nanotube/selenium composites for high performance lithium–selenium battery

Multi-walled carbon nanotube/selenium composites (MWCNT/Se) are prepared via a simple solution-based processing strategy using ethylenediamine as the solvent. The selenium nanoparticles in diameter of about 100 nm are homogeneously deposited on the network of multi-walled carbon nanotubes in the composites. Compared with multi-walled carbon nanotube/selenium composites by melt-infusing method (MWCNT/Se-M), the multi-walled carbon nanotube/selenium composites by solution-based process (MWCNT/Se–S) can deliver a much higher initial discharge capacity (645.7 mAh g−1) and a better cycling stability (355.5 mAh g−1 remaining at a rate of 0.5C after 100 cycles). Even at 4C, it still exhibits a reversible capacity of 468.7 mAh g−1. The superior electrochemical properties of multi-walled carbon nanotube/selenium composites via solution-based process could be ascribed to the diminished size of selenium and uniform distribution of selenium nanoparticles in carbon matrix.

A bimodal porous carbon with high surface area supported selenium cathode for advanced Li–Se batteries

A novel bimodal porous carbon (BPC) with high surface area was prepared by a simple hydrothermal route and KOH activation process, and the Se–BPC composite was synthesized for lithium–selenium batteries by the melt-diffusion method. It is found that the elemental selenium was dispersed inside the pores of BPC based on the analyses. Electrochemical tests reveal that the Se–BPC composite has a large reversible capacity and high rate performance as cathode materials. The Se–BPC (45.1wt.% Se) composite displays an initial discharge capacity of 552mAhg−1 and a reversible discharge capacity of 264mAhg−1 after 80cycles at 1C charge/discharge rate. In particular, the Se–BPC composite presents a durable cycling performance at high rate of 2C. These outstanding electrochemical features of Se–BPC composite cathode should be attributed to the uniform BPC with high surface area and bimodal porous structure. The bimodal porous carbon would be a promising carbon matrix to develop high performance lithium–selenium batteries.

Selenium/carbon-rich core–shell composites as cathode materials for rechargeable lithium–selenium batteries

Selenium/carbon-rich (Se/carbon-rich) core–shell composites are prepared by a one-step hydrothermal synthesis method as a cathode for rechargeable lithium batteries. The Se/carbon-rich composites are characterized and examined by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetry (TGA) measurements. It is demonstrated from galvanostatic discharge/charge process that the Se/carbon-rich composites exhibit the discharge capacity of 558 mA h g−1 in the first cycle and maintain capacity of 181 mA h g−1 after 80 cycles at a rate of 0.5C, which is better than that of the pristine selenium. The result demonstrates that the unique core–shell structure is effective in suppressing the dissolution of polyselenides into the electrolyte and in maintaining high utilization of the active materials during the charge/discharge process. It provides a new selenium-based cathode material for rechargeable lithium batteries.

A selenium-confined porous carbon cathode from silk cocoons for Li–Se battery applications

A composite of selenium (Se) and a rich porous carbon material (PCM) with mesopores from silk cocoons is explored as a cathode for lithium–selenium (Li–Se) batteries for the first time.

High-performance lithium–selenium batteries promoted by heteroatom-doped microporous carbon

Microporous N-doped carbon confined Se as a cathode material for advanced Li–Se battery.

Localized polyselenides in a graphene-coated polymer separator for high rate and ultralong life lithium–selenium batteries

A graphene-coated polymer separator was developed for lithium-selenium batteries with pure selenium powder as the active material. The structure is a simple yet effective strategy for improving Li-Se battery's electrochemical performance, yielding long cycle life up to 1000 cycles with high capacity and excellent rate behavior.

A novel type of one-dimensional organic selenium-containing fiber with superior performance for lithium–selenium and sodium–selenium batteries

A novel type of organic selenide fiber composed of carbonized polyacrylonitrile/selenium (CPAN/Se) has been synthesized by heating polyacrylonitrile–selenium (PAN–Se) fibers via the electrospinning technique at 600 °C. The Se molecules are confined by N-containing carbon ring structures in the form of energy-storing selenium side chains in the carbonized PAN matrix. This unique stable chemical structure with a conductive carbon skeleton connected to the selenium side chains and excellent mechanical stability can allow CPAN/Se composite cathodes to be charged and discharged in a low-cost carbonate-based electrolyte with excellent long cycle stability and quite good rate performance. The superior electrochemical performance of CPAN/Se electrodes is demonstrated in both lithium-ion and sodium-ion batteries, where they have delivered a high capacity of nearly 600 mA h g−1 for 500 cycles in lithium–selenium (Li–Se) batteries and 410 mA h g−1 for 300 cycles in sodium–selenium (Na–Se) batteries at 0.3 C, respectively.

Micro‐ and Mesoporous Carbide‐Derived Carbon–Selenium Cathodes for High‐Performance Lithium Selenium Batteries

Nanocomposites of selenium (Se) and ordered mesoporous silicon carbide‐derived carbon (OM‐SiC‐CDC) are prepared for the first time and studied as cathodes for lithium‐selenium (Li‐Se) batteries. The higher concentration of Li salt in the electrolytes greatly improves Se utilization and cell cycle stability. Se‐CDC shows significantly better performance characteristics than Se‐activated carbon nanocomposites with similar physical properties. Se‐CDC also exhibits better rate performance and cycle stability compared to similarly produced sulfur (S)–CDC for Li/S batteries.

Micro- and Mesoporous Carbon - Selenium Composite Cathode for Lithium / Selenium Battery

The lithium/sulfur (Li/S) cells have demonstrated promising energy density values, exceeding that of the high energy density Li ion cells.[1-3] However, the majority of Li/S cells exhibit poor cycling performance, which is the key limiting factor for the commercialization of such a technology. One of the challenges is the dissolution of intermediate lithium polysulfide species formed during cycling, which induces a shuttle phenomenon. Low intrinsic electric conductivity of S and largely insoluble low order lithium polysulfides (such as Li2S, Li2S2) also deteriorate cycle stability. The somewhat similar lithium-selenium (Li/Se) system was recently found to offer higher rate performance even for the bulk Se.[4] Selenium is an environmentally friendly material, with high theoretical volumetric capacity of ~3260 mAh/cm3 (not considering expansion upon lithiation) and moderately high theoretical gravimetric capacity of 678 mAh/g based on molecular weight of 78.97 g/mol and density of 4.81 g/cm3. High volumetric capacity is particularly attractive for both EV and electronic device applications. Challenges with Li/Se systems are somewhat similar to that of Li/S systems, including polyselenide dissolution during the cell operation and limited (although an order of magnitude higher than in S) electronic conductivity. Several groups utilized porous carbon structure to entrap Se into conductive framework and showed promising results.[5, 6] This approach might be able to both reduce polyselenide dissolution and increase the electrical conductivity of selenium for higher power density.In this study, we have successfully prepared Se infiltrated ordered meso- and microporous silicon carbide derived carbon (CDC) composites with high Se contents (~60 wt. %). 2016 coin cells were assembled using a Li metal foil anode and Se-CDC cathodes with various electrolytes. The cells were tested at different C-rates of C/10, C/5, C/2, and 1C. The durability test was continued at C/5 for 150 cycles.The rate performance of Se-CDC cathodes showed a significant impact of electrolyte composition (Figure 1). The Se-CDC composite exhibits a stabilized discharge capacity of 457 mAh/gse within 3 cycles at 0.1 C charge/discharge rate. However, the cell with electrolytes 1 was slowly missing active material and stabilized only after ~15 cycles. Se utilization in Se-CDC cells was also affected by the electrolyte composition. However, the overall performance of all Li/Se-CDC cells in all electrolytes was rather stable compared to that of the similar Li/S-CDC cells. Very stable performance up to 150 cycles was demonstrated (Figure 2). After 150 cycles, the discharge capacity of the Se-CDC in electrolyte 3 retained approximately 72% of its theoretical capacity, while the same electrode in electrolyte 1 and electrolyte 2 showed relatively poor capacity retention of 39% and 33% respectively.In this talk we will discuss the key performance differences between Se and S cathode chemistries and offer our explanation to the improved Li-Se cell stability.ACKNOWLEDGEMENTSDifferent aspects of this work were supported by the Energy Efficiency & Resources program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) funded by the Korea government Ministry of Knowledge Economy (grant 20118510010030) and by the US Army Research Office (grant W911NF-12-1-0259). REFERENCES1. Ji, X., K.T. Lee, and L.F. Nazar, A highly ordered nanostructured carbon-sulphur cathode for lithium-sulphur batteries. Nature Materials, 2009. 8(6): p. 500-506.2. Lee, J.T., et al., Sulfur-Infiltrated Micro- and Mesoporous Silicon Carbide-Derived Carbon Cathode for High-Performance Lithium Sulfur Batteries. Advanced Materials, 2013. 25(33): p. 4573-4579.3. Song, M.-K., Y. Zhang, and E.J. Cairns, A Long-Life, High-Rate Lithium/Sulfur Cell: A Multifaceted Approach to Enhancing Cell Performance. Nano letters, 2013. 13(12): p. 5891-5899.4. Abouimrane, A., et al., A New Class of Lithium and Sodium Rechargeable Batteries Based on Selenium and Selenium–Sulfur as a Positive Electrode. Journal of the American Chemical Society, 2012. 134(10): p. 4505-4508.5. Luo, C., et al., Selenium@ Mesoporous Carbon Composite with Superior Lithium and Sodium Storage Capacity. ACS nano, 2013. 7(9): p. 8003-8010.6. Yang, C.P., et al., An Advanced Selenium–Carbon Cathode for Rechargeable Lithium–Selenium Batteries. Angewandte Chemie International Edition, 2013. 52(32): p. 8363-8367.

Confining selenium in nitrogen-containing hierarchical porous carbon for high-rate rechargeable lithium–selenium batteries

A novel nitrogen-containing hierarchical porous carbon (NCHPC) was prepared by a simple template process and chemical activation and a selenium/carbon composite based on NCHPC was synthesized for lithium–selenium batteries by a melt-diffusion method. The Se–NCHPC composite was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), and transmission electron microscopy (TEM) measurements. It is found that the elemental selenium was dispersed inside the hierarchical pores of NCHPC. It is demonstrated from cyclic voltammetry (CV) and galvanostatic discharge–charge processes that the Se–NCHPC composite has a large reversible capacity and high rate performance as cathode materials. The Se–NCHPC composite with a selenium content of 56.2 wt% displays an initial discharge capacity of 435 mA h g−1 and a reversible discharge capacity of 305 mA h g−1 after 60 cycles at a 2 C charge–discharge rate. In particular, the Se–NCHPC composite presents a long electrochemical stability at a high rate of 5 C. The results reveal that the electrochemical reaction constrained inside the interconnected macro/meso/micropores of NCHPC would be the dominant factor for the enhancement of the high rate performance of the selenium cathode, and the nitrogen-containing hierarchical porous carbon network would be a promising carbon matrix structure for lithium–selenium batteries.

Selenium encapsulated into 3D interconnected hierarchical porous carbon aerogels for lithium–selenium batteries with high rate performance and cycling stability

Selenium encapsulated into 3D interconnected hierarchical porous carbon aerogels (HPCA) as a carbon/selenium composite material is prepared for lithium–selenium batteries. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations show the hierarchical porous structures of the carbon aerogels and the homogeneous distribution of selenium in the composite. The performance of the HPCA/Se cathode is evaluated in lithium–selenium batteries using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. It is found that the HPCA/Se cathode shows high rate performance, coulombic efficiency and cycling stability. The HPCA/Se cathode has a highest coulombic efficiency which is kept above 98% after 50th cycle in ionic liquid N-methyl-(n-butyl) pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI) modified electrolyte and retains 309 mAh g−1 after 100 discharge/charge cycles at a high rate of 0.5 C (337.5 mAh g−1) in LiNO3 modified electrolyte, respectively. Even at the current density of 5 C (3375 mAh g−1), it can still maintain at a reversible capacity of 301 mAh g−1. The excellent electrochemical properties benefit from the high electron conductivity and 3D interconnected hierarchical porous structures of the carbon aerogels, which contribute to disperse selenium and absorb polyselenides, and suppress the formation of residual Li2Se layer.

TiO2–Se composites as cathode material for rechargeable lithium–selenium batteries

Titania-selenium (TiO 2 –Se) composite cathode materials were successfully synthesized by a simple melt-diffusion method for lithium–selenium batteries. The composites were characterized and examined by X-ray diffraction, nitrogen adsorption/desorption measurements, scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge–discharge tests. It is found that selenium particles and TiO 2 are well-distributed in the composites. The TiO 2 –Se composite cathode can deliver relative high capacity and good cycling performance. The electrochemical results showed that the TiO 2 –Se composite cathode exhibits an initial discharge specific capacity of 481 mAh/g and 158 mAh/g over 50 cycles at 0.1 C, which are higher than that of pristine selenium. The improvements of electrochemical performances were due to the good dispersion of selenium in the pores of TiO 2 particles and the excellent adsorbing effect on polyselenides of TiO 2 . • TiO 2 –Se composites were synthesized by infusing Se into mesoporous TiO 2 . • TiO 2 particles and selenium were well dispersed in composites. • TiO 2 –Se composites exhibit better electrochemical properties than pristine selenium.

A selenium-confined microporous carbon cathode for ultrastable lithium–selenium batteries

A novel selenium-microporous carbon composite was synthesized and exhibited ultrastable cycling performance for rechargeable lithium–selenium batteries.

Improvement of electrochemical performance of rechargeable lithium–selenium batteries by inserting a free-standing carbon interlayer

A simple, low-cost modification of lithium–selenium (Li–Se) cells by placing a carbon interlayer between the selenium electrode and the separator has been investigated to significantly improve the electrochemical performance of Li–Se cells.

An Advanced Selenium–Carbon Cathode for Rechargeable Lithium–Selenium Batteries

An Advanced Selenium–Carbon Cathode for Rechargeable Lithium–Selenium Batteries

An Advanced Selenium–Carbon Cathode for Rechargeable Lithium–Selenium Batteries

Für den Einsatz als Kathodenmaterial in Li-Se-Batterien wurde Selen in Form cyclischer Se8-Moleküle in mesoporösem Kohlenstoff eingeschlossen. Eine Ex-situ-Studie der Se-Kathode offenbart eine Umwandlung der Se8-Ringe in Sen-Ketten während der Zyklisierung. Dies verhindert den Shuttle-Effekt von Se und führt so zu einer verbesserten volumetrischen Kapazitätsdichte und Zyklisierungsstabilität. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.