High Cycling Performance Research Articles

Coupling of Mn2O3 with Heteroatom-Doped Reduced Graphene Oxide Aerogels with Improved Electrochemical Performances for Sodium-Ion Batteries

Currently, efforts to address the energy needs of large-scale power applications have expedited the development of sodium-ion (Na-ion) batteries. Transition-metal oxides, including Mn2O3, are promising for low-cost, eco-friendly energy storage/conversion. Due to its high theoretical capacity, Mn2O3 is worth exploring as an anode material for Na-ion batteries; however, its actual application is constrained by low electrical conductivity and capacity fading. Herein, we attempt to overcome the problems related to Mn2O3 with heteroatom-doped reduced graphene oxide (rGO) aerogels synthesised via the hydrothermal method with a subsequent freeze-drying process. The cubic Mn2O3 particles with an average size of 0.5-1.5 µm are distributed to both sides of heteroatom-doped rGO aerogels layers. Results indicate that heteroatom-doped rGO aerogels may serve as an efficient ion transport channel for electrolyte ion transport in Mn2O3. After 100 cycles, the electrodes retained their capacities of 242, 325, and 277 mAh g-1, for Mn2O3/rGO, Mn2O3/nitrogen-rGO, and Mn2O3/nitrogen, sulphur-rGO aerogels, respectively. Doping Mn2O3 with heteroatom-doped rGO aerogels increased its electrical conductivity and buffered volume change during charge/discharge, resulting in high capacity and stable cycling performance. The synergistic effects of heteroatom doping and the three-dimensional porous structure network of rGO aerogels are responsible for their excellent electrochemical performances.

Vanadium Oxides with Amorphous‐Crystalline Heterointerface Network for Aqueous Zinc‐Ion Batteries

AbstractRechargeable aqueous Zn‐VOxbatteries are attracting attention in large scale energy storage applications. Yet, the sluggish Zn2+diffusion kinetics and ambiguous structure–property relationship are always challenging to fulfil the great potential of the batteries. Here we electrodeposit vanadium oxide nanobelts (VO‐E) with highly disordered structure. The electrode achieves high capacities (e.g., ≈5 mAh cm−2, 516 mAh g−1), good rate and cycling performances. Detailed structure analysis indicates VO‐E is composed of integrated amorphous‐crystalline nanoscale domains, forming an efficient heterointerface network in the bulk electrode, which accounts for the good electrochemical properties. Theoretical calculations indicate that the amorphous‐crystalline heterostructure exhibits the favorable cation adsorption and lower ion diffusion energy barriers compared to the amorphous and crystalline counterparts, thus accelerating charge carrier mobility and electrochemical activity of the electrode.

Investigation of SnS2 -rGO Sandwich Structures as Negative Electrode for Sodium-Ion and Potassium-Ion Batteries.

Sodium-ion and potassium-ion batteries (NIBs and KIBs) are considered promising alternatives to replace lithium-ion batteries (LIBs) in energy storage applications due to the natural abundance and low cost of Na and K. Nevertheless, a critical challenge is that the large size of Na+ /K+ leads to a huge volume change of the hosting material during electrochemical cycling, resulting in rapid capacity decay. Among negative candidates for alkali-metal-ion batteries, SnS2 is attractive due to the competitively high specific capacity, low redox potential and high abundance. Porous few-layer SnS2 nanosheets are in situ grown on reduced graphene oxide, forming a SnS2 -rGO sandwich structure via strong C-O-Sn bonds. This nano-scaled sandwich structure not only shortens Na+ /K+ and electron transport pathways but also accommodates volume expansion, thereby enabling high and stable electrochemical cycling performance of SnS2 -rGO. This work explores the influence of different conductive carbons (Super P and C65) on the SnS2 -rGO electrode. In addition, the effects of the electrolyte additive fluoroethylene carbonate (FEC) on the electrochemical performance in NIBs and KIBs is evaluated. This work provides guidelines for optimized electrode structure design, electrolyte additives and carbon additives for the realization of better NIBs and KIBs.

Influence of carbon sources on the performance of carbon-coated nano-silicon

Silicon-based material is an important anode material for next-generation lithium-ion batteries. In order to overcome its shortcomings, carbon coating is often employed to improve the electrochemical performance. However, the carbon source, carbon content, and different contact and mixing schemes between carbon sources and silicon are all complex factors and need to be clarified. In this study, nano-silicon is coated by the chemical vapor deposition method using different carbon sources, such as acetylene, methane, propane, and propylene. Carbon content after coating is designed to stay at the same level to reduce the experimental error. Results show the sample with higher conductivity provides higher cycle performance. Propylene is the best choice of the four carbon sources studied in this work. These results indicate that the selection of the carbon source is an important factor that plays a significant role in electrochemical performance.

A Review of Remaining Useful Life Prediction for Energy Storage Components Based on Stochastic Filtering Methods

Lithium-ion batteries are a green and environmental energy storage component, which have become the first choice for energy storage due to their high energy density and good cycling performance. Lithium-ion batteries will experience an irreversible process during the charge and discharge cycles, which can cause continuous decay of battery capacity and eventually lead to battery failure. Accurate remaining useful life (RUL) prediction technology is important for the safe use and maintenance of energy storage components. This paper reviews the progress of domestic and international research on RUL prediction methods for energy storage components. Firstly, the failure mechanism of energy storage components is clarified, and then, RUL prediction method of the energy storage components represented by lithium-ion batteries are summarized. Next, the application of the data–model fusion-based method based on kalman filter and particle filter to RUL prediction of lithium-ion batteries are analyzed. The problems faced by RUL prediction of the energy storage components and the future research outlook are discussed.

Mesoporous Gold Film with Surface Sulfur Modification to Enable Dendrite-Free Lithium Plating/Stripping for Long-Life Lithium Metal Anodes.

The formation of a lithiophilic phase is an effective method to inhibit the growth of lithium dendrites and obtain high-performance Li metal anodes (LMAs). Nonetheless, previous studies have overlooked the underlying mechanistic studies that modulate the structure of the lithiophilic phase as well as lithiophilicity. A self-supporting sulfur-modified mesoporous gold film on nickel foam (SMGF@NF) for LMAs is created with mesoporous structure, which can provide sufficient active sites for uniform lithium deposition. The synergistic promotion of lithiophilic gold and sulfurleads to uniform lithium nucleation and induces consistent lithium removal during lithium stripping. The doping of S promotes the decomposition of bistrifluoromethanesulfonimide lithium saltto generate lithium fluorde, thus forming a more stable solid electrolyte interface. Combining the multifaceted advantages of SMGF@NF, its lithium-plated electrode can achieve ultralong cycle life in symmetrical batteries (over 1000h at 0.5mA cm-2 and 1 mAh cm-2 ) and ultralow overpotential (≈10mV). Meanwhile, the Li-SMGF@NF||LiFePO4 full cell achieves a high cycling performance and rate capability (92.4% capacity retention after 1000 cycles at 5 C). The study probes into the composite electrode surface composition and structure, revealing the mechanism of high-performance LMAs.

Development of a Soft Actuator from Fast Swelling Macroporous PNIPAM Gels for Smart Braille Device Applications in Haptic Technology

The development of a cost-efficient braille device is a crucial challenge in haptic technology to improve the integration of visually impaired people. Exclusion of any group threatens the proper functioning of society. Commercially available braille devices still utilize piezoelectric actuators, which are expensive and bulky. The challenge of a more adapted braille device lies in the integration of a high number of actuators─on a millimeter scale─in order to independently move a matrix of pins acting as tactile cues. Unfortunately, no actuation strategy has been adapted to tackle this challenge. In this study, we develop a soft actuator based on a thermosensitive poly(N-isopropylacrylamide) (PNIPAM) gel. We introduce macroporosity to the gel (pores of 10 to 100 μm). It overcomes the diffusion─which is the limiting kinetic factor─and accelerates the gel response time from hours for the bulk gel to seconds for the macroporous gel. We study the properties of porous gels with various porosities. We also compare a mechanically reinforced nanocomposite gel (made of PNIPAM and Laponite clay) to a "classic" gel. As a result, we develop a fast-actuating gel with high cyclic performance. We then develop a single-pin braille setup, where actuation is controlled thanks to a swift temperature control of a macroporous gel cylinder. This new strategy offers a very promising actuation technology. It offers a simple and cost-efficient alternative to the current braille devices.

Facile and Cheap Carbonized Cotton Cloth Interlayer Endows Lithium-Sulfur Batteries with High Performance in All Climates

Lithium-sulfur batteries (LSBs) have proven the potential for future power sources due to the ultrahigh theoretical specific capacity, material abundance, and eco-friendliness. However, the insulation of sulfur and the notorious shuttle effect of polysulfides impede the practical use. In this work, we introduced the hollow carbonized cotton cloth (CCC) as an interlayer by simple one-step carbonization. CCC reduces the charge transfer resistance and inhibits the shuttle effect, enabling LSBs with high rate and cycling performances in all climates. Specifically, the LSBs based on the CCC interlayer deliver rate capacities of 118, 399, and 879 mAh g–1 at 2 C at −30, 0, and 50 °C, respectively. Correspondingly in the 1 C cycling tests, the initial specific capacities are 168, 490, and 885 mAh g–1; the decay rates are 0.029% (1000 cycles), 0.034% (1000 cycles), and 0.056% (800 cycles). Moreover, with a higher sulfur loading of 2.3 mg cm–2, the ambient CCC battery achieves a decay rate of only 0.03% per cycle in the 1 C test (800 cycles). Compared with commercial carbon cloth, the ultralow price, light weight, easily scalable preparation, and all-climate good performance of CCC can extremely push LSBs to practical use in the future.

Novel-designed cobweb-like binder by “four-in-one” strategy for high performance SiO anode

The choice of binder can prodigiously affect the electrochemical performance of the silicon-based anode. Unfortunately, conventional binders with relatively weak intermolecular van der Waals forces have a weak buffering effect on the volume expansion of silicon-based anodes, which leads to electrode contact failure and substantial capacity decay during cycling. Herein, inspired by the spider web, a multifunctional cobweb-like complex binder (TA-PAA) with strong adhesion constructed of tapioca (TA) and polyacrylic acid (PAA) is designed and applied as a high efficiency binder for high capacity and long-term cycle performance SiO anode. Originating from high viscoelasticity, robust tensile, as well as mechanical strength and self-healing property (“four-in-one” effect), TA-PAA/SiO electrode accommodates volumetric stress and addresses electrode contact failure. The electrode delivers a brilliant rate performance (619.2 mA h g−1 at 5 A g−1) and long-term cycle performance (901.2 mA h g−1 over 1200 cycles at 2 A g−1).

Anin situformed copolymer electrolyte with high ionic conductivity and high lithium-ion transference number for dendrite-free solid-state lithium metal batteries

A copolymer electrolyte containing 1,3-dioxolane and 1,3,5-trioxane units was synthesized throughin situpolymerization and exhibits high ionic conductivity, a high lithium-ion transference number and stable cycling performance.

The Microparticles SiOx Loaded on PAN-C Nanofiber as Three-Dimensional Anode Material for High-Performance Lithium-Ion Batteries

Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane (PDMS) and polyacrylonitrile (PAN) as precursors via electrospinning and freeze-drying successfully. In contrast to conventional carbon covering Si-based anode materials, the C/SiOx structure is made up of PAN-C, a 3D carbon substance, and SiOx loading steadily on PAN-C. The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure. When employed as lithium-ion batteries (LIBs) anode materials, C/SiOx-1% composites were discovered to have an extremely high lithium storage capacity and good cycle performance. At a current density of 100 mA/g, its reversible capacity remained at 761 mA/h after 50 charge-discharge cycles and at 670 mA/h after 200 cycles. The C/SiOx-1% composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.

Three-dimensional Ag/carbon nanotube-graphene foam for high performance dendrite free lithium/sodium metal anodes

• Porous 3D Ag/CNT-GF structure effectively alleviates the volume expansion of Li/Na. • Lithiophilic/sodiophilic Ag NPs directionally guide Li/Na deposition. • Dendrite free morphology is achieved in Li/Na@3D Ag/CNT-GF anodes. Although lithium metal and sodium metal are promised as ideal anodes for lithium ion batteries (LIBs) and sodium ion batteries (SIBs), they still suffer from inevitable dendrite growth. In light of this, silver nanoparticles (Ag NPs) are sputtered onto three-dimensional carbon nanotube decorated graphene foam (3D CNT-GF) to construct superior 3D Ag/CNT-GF composite matrix for lithium metal anodes (LMAs) and sodium metal anodes (SMAs). With this design, lithiophilic/sodiophilic Ag NPs could provide favorable sites to guide Li/Na metal nucleation and growth, thus leading to low nucleation overpotentials, high Coulombic efficiency and long cycle performance. Accordingly, 3D Ag/CNT-GF electrodes can stably cycle for 1000 and 750 cycles at 3 mA cm −2 with 1 mAh cm −2 for SMAs and LMAs, respectively. More attractively, it can also stably sustain 300 cycles (SMAs) and 500 cycles (LMAs) at a large current density of 5 mA cm −2 with 1 mAh cm −2 . The excellent electrochemical performance can be attributed to the lithiophilic/sodiophilic electrode surface, 3D porous electrode structure and the dendrite-free morphology as demonstrated by ex-situ scanning electron microscopy (SEM) and in-situ optical microscopy analyses. Furthermore, full cells based on Na@3D Ag/CNT-GF||Na 3 V 2 (PO 4 ) 3 @carbon (NVP@C) and Li@3D Ag/CNT-GF||LiFePO 4 (LFP) could deliver highly reversible capacities of 90.1 and 106.4 mAh g −1 respectively at 100 mA g −1 after 200 cycles for SIBs and LIBs, respectively. This work demonstrates a novel 3D Ag/CNT-GF matrix for boosting Li/Na deposition stability for their future applications. Porous 3D Ag/CNT-GF nanostructure was designed and further adopted as the stable host of lithium/sodium metal anodes. Lithiophilic/sodiophilic Ag NPs directionally guide Li/Na deposition with uniform current density distribution over the 3D Ag/CNT-GF current collector surface, enabling a dendrite free deposition morphology and long cycle stability.

Constructing metal-organic framework-derived carbon incorporated V2O5 nanowire-bundle arrays on carbon nanotube fiber as advanced cathodes for high-performance wearable zinc-ion batteries

Fiber-shaped energy storage devices with light weight, superflexibility, and weavability demonstrate promising prospects for application in wearable and portable electronics. Especially, fiber-shaped aqueous rechargeable zinc ion batteries (FARZIBs), which can facilitate the development of wearable electronic products owing to their high safety, low cost, environmental friendliness. Nevertheless, it is very challenging to achieve high rate capability, energy density, and cycling performance simultaneously for the FARZIBs. Herein, a high-performance FARZIB is created from vanadium-based metal-organic frameworks (MOFs) derived vanadic oxide (V2O5) nanowire-bundle arrays (NBAs) grown on highly conductive carbon nanotube fibers (CNTFs) directly as the binder-free cathode. Profiting from high specific area and porous structure of MOFs, as well as arrays structure and binder-free features, our as-assembled FARZIBs exhibited a high capacity of 0.71 mAh cm−2 at a current density of 2 mA cm−2, and demonstrated outstanding rate capability and prominent cycling performance. Moreover, the FARZIBs delivered an extremely high energy density of 215 mWh cm−3 at a power density of 600 mW cm−3. Therefore, our work brings new prospects for the next generation of wearable electronics.

A calcium looping system powered by renewable electricity for long-term thermochemical energy storage, residential heat supply and carbon capture

Affordable long-term energy storage and CO2 capture technique are imperative to developing the future carbon–neutral energy system. This paper proposed a calcium looping system powered by excess renewable electricity to achieve long-term thermochemical energy storage, residential heat supply and carbon capture. The system can be constructed with industrial equipment and exploit natural, abundant and cheap limestone as the circulating material. The electrical calciner is designed to charge the energy and produce the high-pressured CO2 during the valley of the electricity grid, while the carbonator side is primarily driven by the discharged thermochemical energy and on-demand coordinates the heat network along with the carbon capture. The HEATSEP framework is adopted to optimize heat transfer processes and operating conditions for deriving the most favorable system configuration in the energy and economic aspects. Compared to the reference plant with electric boilers and short-term heat storage tanks, an energy penalty of around 32.3% total energy percentage points should be paid to drive long-term energy storage and carbon capture. The energy penalty is attributed to thermal losses in the calciner and heat exchanger networks, chemical energy lost by the make-up flow of fresh limestone, CO2 compression for storage and auxiliary power for solid/fluid circulations. Due to a comparable total plant investment cost to the reference plant, the proposed system achieves the CO2 avoidance cost of 111.1 RMB/tonCO2, showing some competitiveness over current post-combustion carbon capture techniques. The techno-economic competitiveness of the proposed system can be further strengthened by replacing natural or synthetic Ca-based materials with high cycling performance instead of limestone, as well as extending applicable occasions to achieve almost year-round operation.

All-Solid-State Garnet-Based Lithium Batteries at Work-In Operando TEM Investigations of Delithiation/Lithiation Process and Capacity Degradation Mechanism.

Li7 La3 Zr2 O12 (LLZO)-based all-solid-state Li batteries (SSLBs) are very attractive next-generation energy storage devices owing to their potential for achieving enhanced safety and improved energy density. However, the rigid nature of the ceramics challenges the SSLB fabrication and the afterward interfacial stability during electrochemical cycling. Here, a promising LLZO-based SSLB with a high areal capacity and stable cycle performance over 100 cycles is demonstrated. In operando transmission electron microscopy (TEM) is used for successfully demonstrating and investigating the delithiation/lithiation process and understanding the capacity degradation mechanism of the SSLB on an atomic scale. Other than the interfacial delamination between LLZO and LiCoO2 (LCO) owing to the stress evolvement during electrochemical cycling, oxygen deficiency of LCO not only causes microcrack formation in LCO but also partially decomposes LCO into metallic Co and is suggested to contribute to the capacity degradation based on the atomic-scale insights. When discharging the SSLB to a voltage of ≈1.2versus Li/Li+ , severe capacity fading from the irreversible decomposition of LCO into metallic Co and Li2 O is observed under in operando TEM. These observations reveal the capacity degradation mechanisms of the LLZO-based SSLB, which provides important information for future LLZO-based SSLB developments.

Surface modification of Li3InCl6 provides superior electrochemical performance for LiMn2O4 cathode materials

LiMn2O4 (LMO) is the substance of choice for small and medium-sized energy storage materials in daily life. In this work, Li3InCl6 (LIC) is prepared on the surface of LiMn2O4 by hydrothermal method using InCl3 and LiCl as raw materials. This method stabilizes the LMO crystal structure by uniformly coating the LIC on the LMO surface and effectively maintains the morphology of LMO crystals during the cycling process. SEM and EDS analysis confirm the morphology and homogeneity of the synthesized material LIC on the LMO surface. The prepared material is put into a battery, and the charge-discharge test is carried out at 0.5 C and 1 C. The results show that the LIC surface-modified samples exhibit more than 6% higher cycling performance than the unmodified samples after long cycling.

Thiol-ene crosslinked cellulose-based gel polymer electrolyte with good structural integrity for high cycling performance lithium-metal battery

Gel polymer electrolytes (GPEs) are considered to be one most promising alternative to liquid electrolytes due to their suitability for creating safe and durable solid-state lithium-metal batteries. However, the mechanical properties of GPEs usually deteriorate dramatically when polymer matrices are plasticized by a liquid electrolyte, which leads to significant loss of battery performance. Therefore, the long-term structural integrity and good mechanical strength are critical characteristics of GPEs designed for high-performance batteries. Here, an ecologically compatible cellulose-based GPE with a crosslinked structure is synthesized via a facile and effective thiol-ene click chemistry method. The prepared thiol-ene crosslinked GPE possesses enhanced mechanical strength (10.95 MPa) and rigid structure, which enabled us to fabricate LiFePO4|Li batteries with ultra-long cycling performance. The capacity retention of the crosslinked cellulose-based GPE can be up to 84% at 0.5 C, even after 350 cycles, which is considerably higher than that of non-crosslinked GPE for which rapid decline in capacity occurs after 200 cycles. In addition, a GPE preparation method described in this work compares favorably well with existing commercial electrolytes for lithium metal batteries.

Investigation of rotating detonation gas turbine cycle under design and off-design conditions

As cycle efficiency of gas turbine can be significantly improved due to the pressure gain characteristic of rotating detonation combustion, a cycle calculation model of rotating detonation gas turbine based on component characteristic curves of a single shaft gas turbine of 25 MW and limited maximum flow capacity of rotating detonation combustor was established to investigate the variations of cycle performance and component characteristics under design and off-design conditions. Thereafter, sensitivity analysis of component parameters was conducted to explore the comprehensive reason for change of cycle efficiency increment. The results demonstrated that compared with those of traditional gas turbine, higher cycle performance and lower compressor pressure ratio were gained in rotating detonation gas turbine. Increment of cycle efficiency and cycle net power increment significantly increased with the drop of load, which reached to 0.0248 and 3.261 MW when turbine inlet total temperature was 1450 K and increased to 0.0539 and 4.008 MW when turbine inlet total temperature was 1279 K. Cycle performance was significantly affected by the changes of compressor pressure ratio, compressor efficiency, equivalence ratio of RDC and turbine efficiency, among which turbine efficiency rather than compressor outlet total temperature had the most significant effect on cycle efficiency increment under the calculated conditions.

Design and 3D Printing of Interdigitated Electrode Structures for High-performance Full Lithium-ion Battery

The tradeoff between energy and power densities is a critical challenge for commercial tape-cast lithium-ion batteries (LIBs). In this study, three-dimensional (3D) LIBs with interdigitated electrode structures are designed and fabricated via 3D printing to overcome this tradeoff. The evolution of battery design from tape-cast thin planar electrodes to interdigitated 3D electrodes is discussed. Numerical simulations based on COMSOL Multiphysics are performed to elucidate the advantages of interdigitated battery design. Interdigitated LIBs composed of comb-like 3D high-voltage LiCoO2 (HV-LCO) cathodes and comb-like 3D natural graphite anodes are fabricated via 3D printing. Additionally, printable HV-LCO inks with appropriate rheological properties are developed for 3D printing. HV-LCO half-cells with Li foil as the counter electrode and an interdigitated full battery with NG anodes as the counter electrode are assembled to test the electrochemical performance. The results show that interdigitated full batteries fabricated via 3D printing offer high specific capacities and stable cycling performance. Full batteries with an electrode thickness of 882 µm can achieve a high areal capacity of 5.88 mAh·cm−2 @ 0.1 C, an areal energy density of 41.4 J·cm−2, and an areal power density of 41.0 mW·cm−2 @ 1.0 C, which are approximately 10 times the values afforded by conventional tape-cast thin batteries.

Synthesizing a Gel Polymer Electrolyte for Supercapacitors, Assembling a Supercapacitor Using a Coin Cell, and Measuring Gel Electrolyte Performance.

Supercapacitors (SC) have attracted attention as energy storage devices due to their high density and long cycle performance. SCs used in devices operating in stretchable systems require stretchable electrolytes. Gel polymer electrolytes (GPEs) are an ideal replacement for liquid electrolytes. Polyvinyl alcohol (PVA) and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) have been widely applied as a polymer-matrix-based electrolytes for supercapacitors because of their low cost, chemically stable, wide operating temperature range, and high ionic conductivities. Herein, we describe the procedures for (1) synthesizing a gel polymer electrolyte with PVA and PVDF-HFP, (2) measuring the electrochemical stability of the gel polymer electrolytes by cyclic voltammetry (CV), (3) measuring the ionic conductivity of the gel polymer electrolytes by electrochemical impedance spectroscopy (EIS), (4) assembling symmetric coin cells using activated carbon (AC) electrodes with the PVA- and PVDF-HFP-based gel polymer electrolytes, and (5) evaluating the electrochemical performance using galvanostatic charge-discharge analysis (GCD) and CV at 25 °C. Additionally, we describe the challenges and insights gained from these experiments.