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Anion-intercalation lithium metal batteries (AILMBs) are appealing due to their low cost and fast intercalation/de-intercalation kinetics of graphite cathodes. However, the safety and cycliability of existing AILMBs are constrained by the scarcity of compatible electrolytes. Herein, we showcase that a difluoroester can be applied as electrolyte solvent to realize high-performance AILMBs, which not only endows high oxidation resistance, but also efficiently tunes the solvation shell to enable highly reversible and kinetically fast cathode reaction beyond the trifluoro counterpart. The difluoroester-based electrolyte demonstrates nonflammability, high ionic conductivity, and electrochemical stability, along with excellent electrode compatibility. The Li| |graphite AILMBs reach a high durability of 10000 cycles with only a 0.00128% capacity loss per cycle under fast-cycling of 1 A g−1, and retain ~63% of room-temperature capacity when discharging at −65 °C, meanwhile supply stable power output under deformation and overcharge conditions. The electrolyte design paves a promising path toward fast-rate, low-temperature, durable, and safe AILMBs. The authors report a difluoroester electrolyte to enhance anion intercalation lithium metal batteries (AILMBs), improving safety and cyclability. This enables cost-effective graphitic carbon cathodes, with high durability, stability, and performance. [ABSTRACT FROM AUTHOR]

BackgroundThe modular body structure of plants enables detached plant organs, such as postharvest fruits and vegetables, to maintain active responsiveness to environmental stimuli, including daily cycles of light and darkness. Twenty-four hour light/darkness cycles entrain plant circadian clock rhythms, which provide advantage to plants. Here, we tested whether green leafy vegetables gain longevity advantage by being stored under light/dark cycles designed to maintain biological rhythms.ResultsLight/dark cycles during postharvest storage improved several aspects of plant tissue performance comparable to that provided by refrigeration. Tissue integrity, green coloration, and chlorophyll content were generally enhanced by cycling of light and darkness compared to constant light or darkness during storage. In addition, the levels of the phytonutrient glucosinolates in kale and cabbage remained at higher levels over time when the leaf tissue was stored under light/dark cycles.ConclusionsMaintenance of the daily cycling of light and dark periods during postharvest storage may slow the decline of plant tissues, such as green leafy vegetables, improving not only appearance but also the health value of the crops through the maintenance of chlorophyll and phytochemical content after harvest.

The ever‐growing pursuit of high energy density batteries has triggered extensive efforts toward developing alkali metal (Li, Na, and K) battery (AMB) technologies owing to high theoretical capacities and low redox potentials of metallic anodes. Typically, for new battery systems, the electrolyte design is critical for realizing the battery electrochemistry of AMBs. Conventional electrolytes in alkali ion batteries are generally unsuitable for sustaining the stability owing to the hyper‐reactivity and dendritic growth of alkali metals. In this review, we begin with the fundamentals of AMB electrolytes. Recent advancements in concentrated and fluorinated electrolytes, as well as functional electrolyte additives for boosting the stability of Li metal batteries, are summarized and discussed with a special focus on structure–composition–performance relationships. We then delve into the electrolyte formulations for Na‐ and K metal batteries, including those in which Na/K do not adhere to the Li‐inherited paradigms. Finally, the challenges and the future research needs in advanced electrolytes for AMB are highlighted. This comprehensive review sheds light on the principles for the rational design of promising electrolytes and offers new inspirations for developing stable AMBs with high performance. [ABSTRACT FROM AUTHOR]

Rechargeable halide-ion batteries (HIBs) are good candidates for large-scale due to their appealing energy density, low cost, and dendrite-free features. However, state-of-the-art electrolytes limit the HIBs' performance and cycle life. Here, via experimental measurements and modelling approach, we demonstrate that the dissolutions in the electrolyte of transition metal and elemental halogen from the positive electrode and discharge products from the negative electrode cause the HIBs failure. To circumvent these issues, we propose the combination of fluorinated low-polarity solvents with a gelation treatment to prevent dissolutions at the interphase, thus, improving the HIBs' performance. Using this approach, we develop a quasi-solid-state Cl-ion-conducting gel polymer electrolyte. This electrolyte is tested in a single-layer pouch cell configuration with an iron oxychloride-based positive electrode and a lithium metal negative electrode at 25 °C and 125 mA g–1. The pouch delivers an initial discharge capacity of 210 mAh g–1 and a discharge capacity retention of almost 80% after 100 cycles. We also report assembly and testing of fluoride-ion and bromide-ion cells using quasi-solid-state halide-ion-conducting gel polymer electrolyte. State-of-the-art electrolytes limit the cycle life of halide-ion batteries. Here, the authors report a fluorinated low-polar gel polymer electrolyte capable of improving the stability of the electrolyte and electrode interphases to boost battery performance. [ABSTRACT FROM AUTHOR]

In traditional non‐flammable electrolytes a trade‐off always exists between non‐flammability and battery performance. Previous research focused on reducing free solvents and forming anion‐derived solid‐electrolyte interphase. However, the contribution of solvated anions in boosting the stability of electrolyte has been overlooked. Here, we resolve this via introducing anions into Li+ solvation sheaths using anions with similar Gutmann donor number (DN) to that of solvents. Taking trimethyl phosphate fire‐retardant (DN=23.0 kcal mol−1) and NO3− (DN=22.2 kcal mol−1) as an example, NO3− is readily involved in the Li+ solvation sheath and reduces the polarity of solvent. This results in boosted stability of electrolyte against Li. The developed non‐flammable electrolyte has low viscosity, high ionic conductivity and is low cost. The reversibility of Li‐Cu cell was improved to 99.49 % and the lifespan of practical LMBs was extended by >100 %. [ABSTRACT FROM AUTHOR]

High‐energy lithium‐ion batteries (LIBs) can be realized with the use of nickel‐rich materials, however, their reversible operation requires long‐term cathode‐electrolyte interfacial (CEI) stability, especially for high‐temperature applications, but how the CEIs evolves during operation is still a mystery. The unstable CEIs have been recently ascribed to them generating/disappearing/regenerating during Li+ extraction/insertion by in situ Fourier Transform Infrared Spectroscopy spectrum. Herein, a strategy of insoluble CEI is proposed toward addressing the interfacially induced deterioration of cathodes with a focus on Ni‐rich layered oxides. Incorporating unsaturated units (CC/CC) to siloxane as electrolyte additives advances the commercial LiNi0.8Co0.1Mn0.1O2/graphite cells up to around 300 cycles at 60 °C with more than 85% capacity retention, along with the LiCoO2 cells reaching ≈90% capacity retention over 350 cycles under 80 °C. The experimentally and theoretically detailed investigation shows that the higher unsaturation bond with high reactive sites show more polymerization via a 3D topological pathway to form insoluble CEI species, leading to suppression of parasitic reactions, corrosive acid, transition‐metal dissolution, stress corrosive cracking, and impedance growth. The scientific discoveries of this study highlight the pivotal role of electrode–electrolyte interactions and recapitulates the tried‐and‐true "electrolyte" approach for the future development of high‐energy batteries under extreme temperature conditions. [ABSTRACT FROM AUTHOR]

Lithium-metal batteries have attracted extensive research attention because of their high energy densities. Developing appropriate electrolytes compatible with lithium-metal anodes is of great significance to facilitate their practical application. Currently used electrolytes still face challenges of high production costs and unsatisfactory Coulombic efficiencies of lithium plating/stripping. In this research, we have developed a diluted electrolyte which is compatible with both lithium-metal anode and sulfurized polyacrylonitrile cathode. It presents a very high Li plating/stripping Coulombic efficiency of 99.3% over prolonged cycling, and the as-assembled anode-free Li-S battery maintains 71.5% of the initial specific capacity after 200 cycles at 0.1 A g−1. This work could shed light on designing a low-cost and high-performance liquid electrolyte for next-generation high-energy batteries. [ABSTRACT FROM AUTHOR]

Rechargeable room‐temperature sodium–sulfur (RT Na–S) batteries are a promising energy storage technology, owing to the merits of high energy density and low cost. However, their electrochemical performance has been severely hindered by the poor compatibility between the existing electrolytes and the electrodes. Here, we demonstrate that an all‐fluorinated electrolyte, containing 2,2,2‐trifluoro‐N,N‐dimethylacetamide (FDMA) solvent, 1,1,2,2‐tetrafluoroethyl methyl ether (MTFE) anti‐solvent and fluoroethylene carbonate (FEC) additive, can greatly enhance the reversibility and cyclability of RT Na–S batteries. A NaF‐ and Na3N‐rich cathode electrolyte interphase derived from FDMA and FEC enables a "quasi‐solid‐phase" Na–S conversion, eliminating the shuttle of polysulfides. The MTFE not only reduces polysulfide dissolution, but also further stabilizes the Na anode via a tailored solvation structure. The as‐developed RT Na–S batteries deliver a high capacity, long lifespan, and enhanced safety. [ABSTRACT FROM AUTHOR]

Rechargeable alkali metal (i.e., lithium, sodium, potassium)‐based batteries are considered as vital energy storage technologies in modern society. However, the traditional liquid electrolytes applied in alkali metal‐based batteries mainly consist of thermally unstable salts and highly flammable organic solvents, which trigger numerous accidents related to fire, explosion, and leakage of toxic chemicals. Therefore, exploring non‐flammable electrolytes is of paramount importance for achieving safe batteries. Although replacing traditional liquid electrolytes with all‐solid‐state electrolytes is the ultimate way to solve the above safety issues, developing non‐flammable liquid electrolytes can more directly fulfill the current needs considering the low ionic conductivities and inferior interfacial properties of existing all‐solid‐state electrolytes. Moreover, the electrolyte leakage concern can be further resolved by gelling non‐flammable liquid electrolytes to obtain quasi‐solid electrolytes. Herein, a comprehensive review of the latest progress in emerging non‐flammable liquid electrolytes, including non‐flammable organic liquid electrolytes, aqueous electrolytes, and deep eutectic solvent‐based electrolytes is provided, and systematically introduce their flame‐retardant mechanisms and electrochemical behaviors in alkali metal‐based batteries. Then, the gelation techniques for preparing quasi‐solid electrolytes are also summarized. Finally, the remaining challenges and future perspectives are presented. It is anticipated that this review will promote a safety improvement of alkali metal‐based batteries. [ABSTRACT FROM AUTHOR]

The deployment of high‐energy‐density lithium‐metal batteries has been greatly impeded by Li dendrite growth and safety concerns originating from flammable liquid electrolytes. Herein, we report a stable quasi‐solid‐state Li metal battery with a deep eutectic solvent (DES)‐based self‐healing polymer (DSP) electrolyte. This electrolyte was fabricated in a facile manner by in situ copolymerization of 2‐(3‐(6‐methyl‐4‐oxo‐1,4‐dihydropyrimidin‐2‐yl)ureido)ethyl methacrylate (UPyMA) and pentaerythritol tetraacrylate (PETEA) monomers in a DES‐based electrolyte containing fluoroethylene carbonate (FEC) as an additive. The well‐designed DSP electrolyte simultaneously possesses non‐flammability, high ionic conductivity and electrochemical stability, and dendrite‐free Li plating. When applied in Li metal batteries with a LiMn2O4 cathode, the DSP electrolyte effectively suppressed manganese dissolution from the cathode and enabled high‐capacity and a long lifespan at room and elevated temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Due to high energy density, low cost, and nontoxicity, lithium–sulfur (Li–S) batteries are considered as the most promising candidate to satisfy the requirement from the accelerated development of electric vehicles. However, Li–S batteries are subjected to lithium polysulfides (LiPSs) shuttling due to their high dissolution in liquid electrolyte, resulting in low columbic efficiency and poor cycling performance. Moreover, the Li metal as an indispensable anode of Li–S batteries shows serious safety issues derived from the lithium dendrite formation. The replacement of liquid electrolytes with solid‐state electrolytes (SSEs) has been recognized as a fundamental approach to effectively address above problems. In this review, the progress on applying various classes of SSEs including gel, solid‐state polymer, ceramic, and composite electrolytes to solve the issues of Li–S batteries is summarized. The specific capacity of Li–S batteries is effectively improved due to the suppression of LiPSs shuttling by SSEs, while the rate and cycling performance remain relatively poor owing to the limited ionic conductivity and high interfacial resistance. Designing smart electrode/electrolyte integrated architectures, enabling the high ionic transportation pathway and compatible electrode/electrolyte interface, may be an effective way to achieve high performance solid‐state Li–S batteries. [ABSTRACT FROM AUTHOR]

A hierarchical all-solid-state electrolyte based on nitrile materials (SEN) is prepared via in situ synthesis method. This hierarchical structure is fabricated by in situ polymerizing the cyanoethyl polyvinyl alcohol (PVA-CN) in succinonitrile (SN)-based solid electrolyte that is filled in the network of polyacrylonitrile (PAN)-based electrospun fiber membrane. The crosslinked PVA-CN polymer framework is uniformly dispersed in the SN-based solid electrolyte, which can strongly enhance its mechanical strength and keeps it in a quasi-solid state even over the melting point. The electrospun fiber membrane efficiently reduces the thickness of SEN film besides a further improvement in strength. Because of the unique hierarchical structure and structure similarity among the raw materials, the prepared SEN film exhibits high room-temperature ionic conductance (0.30 S), high lithium ion transference number (0.57), favorable mechanical strength (15.31 MPa), excellent safety, and good flexibility. Furthermore, the in situ synthesis ensures an excellent adhesion between SEN and electrodes, which leads to an outstanding electrochemical performance for the assembled LiFePO4/SEN/Li cells. Both the superior performance of SEN and the simple fabricating process of SEN-based all-solid-state cells make it potentially as one of the most promising electrolyte materials for next generation lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: The co-existence of two mechanisms, the surface chemisorption mechanism (SCM) and the tunnel storage mechanism (TSM), for the charge storage of MnO2 is investigated. Sample α-MnO2 whose tunnels (2×2) are almost vacant is synthesized by chemical co-precipitation technique. To verify whether the charge storage of as-prepared α-MnO2 involves the charges based on the SCM besides the TSM, Ba2+ and K+ are intercalated into the tunnels of α-MnO2 by refluxing and samples Ba-MnO2 and K-MnO2 are obtained, respectively. By powder X-ray diffraction, ICP and the extraction test, it is confirmed that Ba2+ and K+ occupy the tunnels and are difficult to remove. By electrochemical analyses, we have found that the charge storage of Ba-MnO2 and K-MnO2 basically depends on the SCM, as Ba2+ and K+ stabilized in the tunnels in advance block the intercalation/deintercalation of cations from the electrolyte. Thus, it can be inferred that for α-MnO2 two mechanisms contribute to the charge storage. The contributions of α-MnO2''s mechanisms are estimated. The charges based on the TSM predominantly account for 81.2–89.9% of the total charges. The charges on the SCM may contribute to 7.9–16.8% and are not negligible. The charges from double-layer capacitance may be negligible, since it is only 1.1–4.1%. [Copyright &y& Elsevier]

The activation characteristics and the effects of current densities on the formation of a separate LiCoO and graphite electrode were investigated and the behavior also was compared with that of the full LiCoO/graphite batteries using various electrochemical techniques. The results showed that the formation current densities obviously influenced the electrochemical impedance spectrum of Li/graphite, LiCoO/Li, and LiCoO/graphite cells. The electrolyte was reduced on the surface of graphite anode between 2.5 and 3.6 V to form a preliminary solid electrolyte interphase (SEI) film of anode during the formation of the LiCoO/graphite batteries. The electrolyte was oxidized from 3.95 V vs Li/Li on the surface of LiCoO to form a SEI film of cathode. A highly conducting SEI film could be formed gradually on the surface of graphite anode, whereas the SEI film of LiCoO cathode had high resistance. The LiCoO cathode could be activated completely at the first cycle, while the activation of the graphite anode needed several cycles. The columbic efficiency of the first cycle increased, but that of the second decreased with the increase in the formation current of LiCoO/graphite batteries. The formation current influenced the cycling performance of batteries, especially the high-temperature cycling performance. Therefore, the batteries should be activated with proper current densities to ensure an excellent formation of SEI film on the anode surface. [ABSTRACT FROM AUTHOR]

Manganese dioxide exhibits the ideal capacitive behavior in aqueous electrolytes containing alkaline-earth cations (Mg[sup2+], Ca[sup2+] or Ba[sup2+]). A specific capacitance value as high as 325 F g[sup-1] was obtained in 0.1 mol L[sup-1] Mg(NO[sub3])[sub2] electrolyte at 2 mV s[sup-1]. The ideal capacitive behavior, high specific capacitance, good coulombic efficiency, and rate ability of manganese dioxides in aqueous electrolytes containing bivalent cations (Mg[sup2+], Ca[sup2+], or Ba[sup2+]) indicate that these alkaline-earth cations might be good alternatives for the state-of-the-art univalent alkaline cations. Moreover, activated carbon/MnO[sub2] asymmetric capacitors with 2 V operating voltage were built up based on the aqueous electrolytes containing these alkaline-earth cations. The energy density of the AC/MnO[sub2] asymmetric capacitor with Ca[sup2+] cation at a current density of 0.3 A g[sup-1] was found to be 21 Wh Kg[sup-1]. [ABSTRACT FROM AUTHOR]

Abstract: Manganese dioxide has been synthesized by a self-reacting microemulsion method. The result of X-ray diffraction shows that lack of clear peaks and broadening of peaks indicate its amorphous nature. Typical cyclic voltammograms were measured in 0.5molL−1 Na2SO4 aqueous solution and the potential ranges were controlled from −0.5 to 0.5, from −0.65 to 0.65, and from −0.75 to 0.75V versus Hg/Hg2SO4 at a sweep rate of 2mVs−1. Rectangular and symmetric image was observed between −0.5 and 0.5V indicating high electrochemical reversibility in this potential and sweep rate. The influence of cation species and concentration (activity) on electrochemical performances of MnO2 is also discussed in this work. Cyclic voltammetric experiments have been performed between −0.5 and 0.5V versus Hg/Hg2SO4 in Li2SO4, Na2SO4 and K2SO4 aqueous solutions with different salt concentrations ranging from 0.05 to 1molL−1. The specific capacitance of MnO2 was found to depend strongly on the cation concentration and species, and specific capacitance value will increase with the increase of cation concentration for all electrolytes. The logarithmic dependence of capacitance of MnO2 on cation activity indicates that the charge storage for MnO2 is involved in a fast redox reaction through cation insertion. [Copyright &y& Elsevier]

Metallic lithium is a promising anode to increase the energy density of rechargeable lithium batteries. Despite extensive efforts, detrimental reactivity of lithium metal with electrolytes and uncontrolled dendrite growth remain challenging interconnected issues hindering highly reversible Li-metal batteries. Herein, we report a rationally designed amide-based electrolyte based on the desired interface products. This amide electrolyte achieves a high average Coulombic efficiency during cycling, resulting in an outstanding capacity retention with a 3.5 mAh cm−2 high-mass-loaded LiNi0.8Co0.1Mn0.1O2 cathode. The interface reactions with the amide electrolyte lead to the predicted solid electrolyte interface species, having favorable properties such as high ionic conductivity and high stability. Operando monitoring the lithium spatial distribution reveals that the highly reversible behavior is related to denser deposition as well as top-down stripping, which decreases the formation of porous deposits and inactive lithium, providing new insights for the development of interface chemistries for metal batteries. Interface chemistry is essential for highly reversible lithium-metal batteries. Here the authors investigate amide-based electrolyte that lead to desirable interface species, resulting in dense Li-metal plating and top-down Li-metal stripping, responsible for the highly reversible cycling. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium metal battery is the most promising next‐generation energy storage device. However, the low ionic conductivity of solid electrolytes and high interfacial impedance with electrode are the main factors to limit the development of all‐solid‐state batteries. In this work, a low resistance–integrated all‐solid‐state battery is designed with excellent electrochemical performance that applies the polyethylene oxide (PEO) with lithium bis(trifluoromethylsulphonyl)imide as both binder of cathode and matrix of composite electrolyte embedded with Li7La3Zr2O12 (LLZO) nanowires (PLLN). The PEO in cathode and PLLN are fused at high temperature to form an integrated all‐solid‐state battery structure, which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee high efficient ion transportation during long cycling. The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of composite electrolyte efficiently, which induces the uniform deposition of lithium metal, thereby suppressing the lithium dendrite growth. The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60 °C. The integrated LiFePO4/PLLN/Li batteries show excellent cycling stability at both 60 and 45 °C. The study proposed a novel and robust battery structure with outstanding electrochemical properties. A low resistance–integrated all‐solid‐state Li metal battery with excellent electrochemical performance is designed. The structure not only guarantees high ionic conductivity and good mechanical properties to suppress lithium dendrite growth by using polyethylene oxide (PEO)/lithium bis(trifluoromethylsulphonyl)imide embedded with Li7La3Zr2O12 nanowire composite electrolyte, but also decreases the interfacial impedance by applying PEO in both electrolyte and cathode that can fuse during operation. [ABSTRACT FROM AUTHOR]

Abstract NaCl dispersant is developed to obtain submicron Sn 4 P 3 (∼500 nm) via high energy mechanical milling. The effect of particle size on the sodium storage performance of Sn 4 P 3 is evaluated based on micron-sized Sn 4 P 3 (∼1.4 μm) and submicron Sn 4 P 3 (∼500 nm). It is found that reducing particle size, in general, can help to stabilize the cycle stability of Sn 4 P 3 due to the suppressed Sn agglomeration and/or the minimized possible particle pulverization. On the other hand, large surface area exacerbates the electrolyte decomposition. The long cycle life of submicron Sn 4 P 3 can be achieved via refilling electrolyte during operation (submicron Sn 4 P 3 delivers a high reversible capacity of ∼450mAh/g after 100 cycles at 100 mA/g in 1.5–0.01 V with refilling electrolyte at 50th cycle). Highlights • Submicron Sn 4 P 3 (∼500 nm) is prepared via high-energy mechanical milling. • NaCl milling dispersant helps to avoid the aggregation of submicron Sn 4 P 3. • Particle size effect on the electrochemical performance of Sn 4 P 3 is investigated. • Submicron Sn 4 P 3 shows much better cycle stability than that of micron Sn 4 P 3. [ABSTRACT FROM AUTHOR]

In article number 1500353, Yan‐Bing He, Feiyu Kang, and co‐workers report the successful preparation of a hierarchical all‐solid‐state electrolyte based on nitrile materials via an in‐situ synthesis method. This electrolyte exhibits low flammability, excellent flexibility, and outstanding electrochemical performance, and has particular applications potential in wearable devices and electric vehicles. [ABSTRACT FROM AUTHOR]

Abstract: The lithium ion batteries using Li4Ti5O12 as the anode material are easily being inflated during charge and discharge, which, however, does not occur in the batteries using graphite as the anode material. The high reduction reactivity of electrolyte on the Li4Ti5O12 material may be the main reason. In this work, the reduction reactivities of electrolyte on the uncoated and carbon-coated Li4Ti5O12 electrodes are compared for the first time. The results show that the reduction decomposition of electrolyte does occur on the uncoated Li4Ti5O12 electrode at around 0.7V, while it only takes place at the first cycle on the carbon-coated Li4Ti5O12 electrode. The carbon coating layers cover the catalytic active sites of Li4Ti5O12 particles and separate the Li4Ti5O12 particles from the electrolyte. A successive solid electrolyte interface (SEI) film is formed on the carbon layer during the formation process, which can prevent the further reduction decomposition of electrolyte at around 0.7V. The impurity phases of rutile and anatase TiO2 do not influence the reduction reactivity of electrolyte. This work is not only important to understand the reduction decomposition mechanism of electrolyte on the Li4Ti5O12 electrode, but also provides an effective solution to suppress the reduction decomposition of electrolyte in the batteries. [Copyright &y& Elsevier]

Abstract: Effect of the electrolyte particularities on manganese dioxide in the neutral electrolytes containing alkaline (Li+, Na+, or K+) and alkaline-earth (Mg2+, Ca2+, or Ba2+) metal cations for electrochemical capacitor is investigated by cyclic voltammetry and electrochemical impedance spectroscopy. A very high capacitance of 357.9Fg−1 is measured when Ca2+ ion is used as electrolyte cation. The results show that cations of the electrolyte instead of proton or anions are responsible for the pseudo-capacitive behavior of manganese dioxide. The capacitance of manganese dioxide is found to depend strongly on the electrolyte particularities, for example, pH value, cation and anion species, and salt concentrations. A logarithmic dependence of capacitance of MnO2 on cation activity is obtained for all alkaline and alkaline-earth metal cations. The capacitance of MnO2 can be doubled by replacing univalent cation with bivalent cation at a close cation activity. [Copyright &y& Elsevier]

Abstract: A porous carbon was prepared using halloysite as a template and sucrose as carbon source by means of template method. Nitrogen adsorption analysis showed that the obtained porous carbon material possess a wide pore size distribution and a large pore volume, especially in the range of mesopores. The application of the resultant carbon for electrodes of electric double layers capacitor (EDLC) in organic LiPF6/PE+CE electrolyte indicated that the specific capacitance, as high as 232F/g at a current density of 0.05mA/cm2, was larger than for commercially activated carbons. Cyclic voltammetry (CV) also showed that the performance of templated carbon in 1mol/l aqueous solution of H2SO4 was better at a large scan rate than for the commercial activated carbons. [Copyright &y& Elsevier]

• Micron-sized Sn 4 P 3 was prepared via high energy mechanical milling. • Initial capacity of Sn 4 P 3 in diglyme-based electrolyte is as high as 960.3 mAh/g. • Sn 4 P 3 shows a record capacity of 719.7 mAh/g after 100 cycles. • ICE of Sn 4 P 3 anode in diglyme-based electrolyte reaches up to 89.8%. • The superior sodium storage performance of Sn 4 P 3 is enabled by diglyme-derived SEI. Sodium-ion batteries (SIBs) have great potential for large scale energy storage applications due to geopolitical abundance of sodium resource. However, the development of SIBs is hindered by the available anodes with high reversible capacity and long cycle life. Herein, we report that micron-sized Sn 4 P 3 anode delivers superior sodium storage performance when used in combination with diglyme-based electrolyte. The first reversible capacity of Sn 4 P 3 anode in diglyme-based electrolyte reaches up to 960.3 mAh/g at current density of 100 mA/g, and a record capacity after 100 cycles (i.e. 719.7 mAh/g) is achieved for Sn 4 P 3 -based anodes to date. Moreover, the initial Coulombic efficiency of the anode is 89.8%, which is one of the highest values among Sn 4 P 3 -based anodes. Ex-situ SEM and XPS study reveals that the outstanding performance is mainly enabled by the ether-derived solid electrolyte interphase, which preserves the integrity of electrode and constructs a robust interphase with favorable kinetics. [ABSTRACT FROM AUTHOR]

Abstracts Hollow and urchin-like CoCO 3 dumbbell microspheres (HCCM) and CoCO 3 @reduced graphene oxide composite microspheres (CC@rGO) were synthesized by one-step solvothermal methods. RGO modification significantly improves the cycling stability of CoCO 3 microsphere anodes at low current densities. CC@rGO delivers 1067 and 997 mAh/g after 50 cycles at 0.1 C and 100 cycles at 0.2 C, respectively. Interestingly, HCCM shows rising cycling stability with increased rates while CC@rGO exhibits slight and continuous capacity fading at almost all rates thus declining advantage with rising rates. A competition theory between “protective force” mainly from solid electrolyte interface (SEI) or rGO layer and “destructive force” from volume swing applied on the microspheres was raised to clarify this phenomenon. The changing volume swing degree and SEI formation rate with increased rates, as well as different protective effects of HCCM and CC@rGO's SEI film or rGO layer, determined various competition results of the two forces at each rate thus various structural stability and cycling performance of the two samples. Furthermore, the application prospect of CoCO 3 anodes in lithium ion full cells has been explored and the assembled LiCoO 2 ||CC@rGO exhibits an initial coulombic efficiency of 92.9%, a discharge mid-voltage of 2.3 V and stable cycling performance. [ABSTRACT FROM AUTHOR]