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Sodium‐ion battery is a potential application system for large‐scale energy storage due to the advantage of higher nature abundance and lower production cost of sodium‐based materials. However, there exist inevitably the safety problems such as flammability due to the use of the same type of organic liquid electrolyte with lithium‐ion battery. Gel polymer electrolytes are being considered as an effective solution to replace conventional organic liquid electrolytes for building safer sodium‐ion batteries. In this review paper, the authors present a comprehensive overview of the research progress in electrochemical and physical properties of the gel polymer electrolyte‐based sodium batteries. The gel polymer electrolytes based on different polymer hosts namely poly(ethylene oxide), poly(acrylonitrile), poly(methyl methacrylate), poly(vinylidene fluoride), poly(vinylidene fluoride‐hexafluoro propylene), and other new polymer networks are summarized. The ionic conductivity, ion transference number, electrochemical window, thermal stability, mechanical property, and interfacial issue with electrodes of gel polymer electrolytes, and the corresponding influence factors are described in detail. Furthermore, the ion transport pathway and ion conduction mechanism are analyzed and discussed. In addition, the advanced gel polymer electrolyte systems including flame‐retardant polymer electrolytes, composite gel polymer electrolytes, copolymerization, single‐ion conducting polymer electrolytes, etc. with more superior and functional performance are classified and summarized. Finally, the application prospects, development opportunities, remaining challenges, and possible solutions are discussed. [ABSTRACT FROM AUTHOR]

Silicon as one of the most promising anode materials suffers from its low electronic conductivity and large volume changes during the lithiation/delithiation processes, resulting in a huge capacity fading upon cycling. Herein, we design a single-wall carbon nanotube (SWCNT) coating on the silicon/carbon (Si/C) electrode to improve its cycling performance. By this simple configuration, the commercial Si/C electrode delivers a high reversible capacity of 653.8 mA h g−1 at current density of 65 mA g−1 and exhibits excellent cycling stability with capacity retention 79.8% after 150 cycles. As expected, the SWCNT layer on the surface of electrode improves the electronic conductivity of the electrode and serves as a barrier layer to prevent the electrode surface from cracking and delaminating, which gives the best reversible capacity and longer life cycle. This design can eliminate much more complicated processes for providing some potential in commercial applications. [ABSTRACT FROM AUTHOR]

Background: No study has demonstrated the effects of sodium bicarbonate plus caffeine (NaHCO3 + CAF) on power output (PO) distribution (e.g., pacing), physiological parameters and energy system contribution during a 4-km cycling time trial (TT). Thus, we aimed to investigate the effects of NaHCO3 + CAF on pacing, physiological parameters, and energy system contribution during a 4-km cycling TT. Methods: Using a double-blind and counterbalanced design, 10 cyclists performed three ingestion protocols (NaHCO3 + CAF, NaHCO3 and placebo) followed by a 4-km cycling TT. Results: 100 min after substance ingestion, the magnitude of change in blood pH and bicarbonate concentration [HCO3–] for NaHCO3 + CAF (+0.04 ± 0.03 and +5.9 ± 1.6 mmol·L−1, respectively, P <.05) and NaHCO3 (+0.02 ± 0.03 and +4.1 ± 2.0 mmol·L−1, respectively, P <.05) was more pronounced than in placebo (−0.01 ± 0.02 and 0.4 ± 0.9 mmol·L−1, respectively). The increase in plasma lactate concentration was more pronounced in NaHCO3 + CAF than in NaHCO3 and placebo (P <.05). Mean ventilation and carbon dioxide production were higher in NaHCO3 + CAF compared to NaHCO3 and placebo (P <.05). The PO and anaerobic power output were increased at the beginning of the 4-km TT (P <.05) in NaHCO3 + CAF compared to the other two conditions, resulting in an improved overall performance (P <.05). Conclusion: NaHCO3 + CAF results in a higher PO and increased anaerobic contribution and respiratory parameters during a 4-km cycling TT. [ABSTRACT FROM AUTHOR]

Electrochromic energy storage devices (EESDs) are incorporating electrochromic and energy storage functions, which can visually display energy storage levels in real‐time to promote the next generation of transparent battery development. However, their performances are still limited for practical applications. Herein, a self‐powered EESD based on complex niobium tungsten oxide is designed using aqueous Zn2+ and hybrid Zn2+/Mn+ (Mn+ = Al3+, Mg2+, and K+) electrolytes. The results reveal that the use of Zn2+/Al3+ hybrid electrolyte achieves superior electrochromic performances including a short self‐coloring time, high optical contrast, and excellent cyclic stability. Furthermore, it is also found that the self‐coloring process is accompanied by a high discharged capacity of niobium tungsten oxide, with high optical modulation in the Zn2+/Al3+ hybrid electrolyte. The detailed mechanism on the performances of EESD using various electrolytes is systematically studied. This work provides a simple and effective strategy for an aqueous and self‐powered EESD with high optical contrast and good cycle stability. [ABSTRACT FROM AUTHOR]

Semi-solid lithium slurry battery is an important development direction of lithium battery. It combines the advantages of traditional lithium-ion battery with high energy density and the flexibility and expandability of liquid flow battery, and has unique application advantages in the field of energy storage. In this study, the thermal stability of semi-solid lithium slurry battery material system was investigated for the first time employing C80 micro-calorimeter. In this new electrode material system, the heat generation of the electrolyte is the decisive factor for its thermal stability. Then, the measurement of in-situ dynamic cycle heat generation of semi-solid lithium slurry battery indicated a lower heat generation than traditional lithium-ion battery. What's more commendable is that its electrochemical performance is basically the same as traditional lithium-ion battery. In addition, through the HPPC test, the mechanism of semi-solid lithium slurry battery cycle heat generation was explained. So, in this work, a preliminary evaluation on the safety and cycling stability of semi-solid lithium slurry battery is carried out. The electrochemical performance test affirms the application prospects of semi-solid lithium slurry battery, and the evaluation on the fire safety provides a reference for the future industrial applications of semi-solid lithium slurry battery. [ABSTRACT FROM AUTHOR]

The intake of anthocyanin-rich New Zealand blackcurrant (NZBC) extract (300 mg per day) over a week enhanced 16.1 km cycling time trial (TT) performance in endurance-trained cyclists without acute performance effects. In the present study, the acute effects of an intake of 900 mg of NZBC extract 2 h before performing the 16.1 km cycling TT were examined. A total of 34 cyclists (26 males; 8 females) (age: 38 ± 7 years, V ˙ O2max: 57 ± 5 mL·kg−1·min−1) completed 4 16.1 km TTs (2 familiarization and 2 experimental trials) over 4 mornings on a home turbo-trainer connected with the online training simulator ZWIFT. There was no difference in time to complete the 16.1 km TT between conditions (placebo: 1422 ± 104 s; NZBC extract: 1414 ± 93 s, p = 0.07). However, when participants were split between faster (<1400 s; 1 female; 16 males) and slower (>1400 s; 7 females; 10 males) cyclists based on average familiarization TTs, a difference in TT performance was observed only in the slower group (placebo: 1499 ± 91 s; NZBC extract: 1479 ± 83 s, p = 0.02). At 12 km (quartile analysis), power output (p = 0.04) and speed (p = 0.04) were higher compared to the placebo with no effects on heart rate and cadence. The acute effects of 900 mg of NZBC extract on a 16.1 km cycling time-trial may depend on the performance ability of male endurance-trained cyclists. More work is needed to address whether there is a sex-specific time-trial effect of NZBC extract independent of performance ability. [ABSTRACT FROM AUTHOR]

Abstract The high energy density, low cost, and low toxicity of LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes has led to their large‐scale mass production. However, the poor interfacial stability between NCM811 and organic electrolytes impairs the long‐cycle performance of lithium ions batteries. In this study, carbonized polymer dots (CPDs) are successfully introduced onto the surface of NCM811 (NCM811@CPDs) via a simple physical mixing process. CPDs with rich surface oxygen functional groups form strong covalent bonds with transition metal (TM) ions at the NCM811 surface, distinctly restraining surface structure degradation, and transition metal ion dissolution. Furthermore, CPDs facilitate the formation of a compact and steady cathode electrolyte interface (CEI) layer during electrochemical cycling. As a result, the NCM811@1 wt% CPDs exhibit enhanced cycling performance with a capacity retention of 89.77% after 100 cycles at 0.5 C compared to 55.39% of the bare NCM811. This facile and effective surface decoration strategy provides valuable guidance for improving the stability and cycling performance of Ni‐rich cathodes.

Abstract The widespread promotion of the sulfur‐based cathode is continuously threatened by the dissolution or slow kinetic reactions of polysulfides, resulting in a deterioration of capacity and volume expansion. Herein, a hierarchical imine‐based covalent organic framework (COFs) with AA stacking structure is constructed as a sulfur host matrix. The one‐dimensional channels in COF are decorated with polarized methoxy groups which can confine and immobilize sulfur species through weak interactions, alleviating the shuttle effect during the battery tests. The composite electrode (COF@S) is fabricated through the melt‐diffusion method in one‐pot synthesis and exhibits a slow fading rate (0.20% each cycle) in a 0.5 C stability test. A promising mechanism for constructing the cathode composite is demonstrated in lithium‐sulfur chemistry in this work.

The implementation of a functional separator represents a highly encouraging approach to mitigating polysulfide shuttling in lithium–sulfur (Li–S). In this study, a two-dimensional (2D) 1,3,5-triformylphloroglucinol (Tp)-p-phenylenediamine (Pa) covalent organic framework/reduced graphene oxide (rGO) functional layer was introduced to enhance the performance of the commercial separator in Li–S batteries. The resulting 2D TpPa@rGO modified separators exhibit significantly improved electronic and ionic conductivity when compared to the unmodified separator, effectively mitigating lithium polysulfide shuttling and enhancing sulfur cathode utilization. It is indicated that a heterostructured composite of a nitrogen-group-containing COF and an electronic conductive addictive is an effective modification to the separator. Consequently, the modified cell demonstrated a minimal degradation rate of only 0.12% per cycle over 350 cycles at 0.5 C.

Abstract The construction of stable cathode electrolyte interphase (CEI) is the key to improve the NCM811 particle structure and interfacial stability via electrolyte engineering. In He’s work, lithium hexamethyldisilazide (LiHMDS) as the electrolyte additive is proposed to facilitate the generation of stable CEI on NCM811 cathode surface and eliminate H2O and HF in the electrolyte at the same time, which boosts the cycling performance of Li||NCM811 battery up to 1000 or 500 cycles with 4.5 V cut-off voltage at 25 or 60 °C.

As females have been hypothesized to have more fatigue resistant inspiratory muscles, this study aimed to compare the development of inspiratory and leg muscle fatigue between males and females following high-intensity cycling. Cross-sectional comparison. 17 healthy young males (27 ± 6 years, V̇O 2peak 55 ± 10 ml･min−1･kg−1) and females (25 ± 4 years, V̇O 2peak 45 ± 7 ml･min−1･kg−1) cycled until exhaustion at 90% of the peak power output achieved during an incremental test. Changes in quadriceps and inspiratory muscle function were assessed via maximal voluntary contractions (MVC) and assessments of contractility via electrical stimulation of the femoral nerve and cervical magnetic stimulation of the phrenic nerves. Time to exhaustion was similar between sexes (p = 0.270, 95% CI − 2.4 – 0.7 min). MVC of the quadriceps was lower after cycling for males (83.9 ± 11.5% vs. 94.0 ± 12.0% of baseline for females, p = 0.018). Reductions in twitch forces were not different between sexes for the quadriceps (p = 0.314, 95% CI − 5.5 – 16.6 percent-points) or inspiratory muscles (p = 0.312, 95% CI − 4.0 – 2.3 percent-points). Changes in inspiratory muscle twitches were unrelated to the different measures of quadriceps fatigue. Females incur similar peripheral fatigue in the quadriceps and inspiratory muscles compared with men following high-intensity cycling, despite smaller reduction in voluntary force. This small difference alone does not seem sufficient to warrant different training strategies to be recommended for women. [ABSTRACT FROM AUTHOR]

Considerable research has been devoted to the development of cathode materials for Al-ion batteries, but challenges remain regarding the behavior of aluminum anodes. Inert oxide (Al2O3) film on Al surfaces presents a barrier to electrochemical activity. The structure of the oxide film needs to be weakened to facilitate ion transfer during electrochemical activity. This study addresses oxide film challenges by studying Al alloy anodes with different iron content. The results reveal that using an anode of 99% Al 1% Fe in a cell increases the cycling lifetime by 48%, compared to a 99.99% Al anode. The improvement observed with the 99% Al 1% Fe anode is attributed to its fractional surface area corrosion being about 12% larger than that of a 99.99% Al anode. This is coupled to precipitation of a higher number of Al3Fe particles, which are evenly scattered in the Al matrix of 99% Al 1% Fe. These Al3Fe particles constitute weak spots in the oxide film for the electrolyte to attack, and access to fresh Al. The addition of iron to an Al anode thus offers a cheap and easy route for targeting the oxide passivating film challenge in Al-ion batteries. [ABSTRACT FROM AUTHOR]

Endurance athletes attribute performance not only to physiological factors, but also refer to psychological factors such as motivation. The goal of this study was to quantify the proportion of the variance in endurance performance that is explained by psychological factors in addition to the physiological factor VO2max. Twenty-five athletes of the U17 Swiss Cycling national team (7f, 18 m, 15.3 ± 0.5 years) were examined in a cross-sectional study with psychological factors and VO2max as independent variables and endurance performance in road cycling as dependent variable. Questionnaires were used to assess psychological factors (i.e. use of mental techniques, self-compassion, mental toughness, achievement motivation, and action vs. state orientation). VO2max was measured by a step incremental cycle ergometer test of exhaustion. Endurance performance was measured in a cycling mountain time trial (1,320 m long, incline of 546 meters). A multiple regression model was created by using forward selection of regression model predictors. Results showed that higher VO2max values (β =.48), being male (β =.26), and higher achievement motivation (i.e. perseverance, β =.11) were associated with a better endurance performance. A more frequent use of one particular mental technique (i.e. relaxation techniques, β =.03) was associated with a worse endurance performance. Our study shows that a physiological factor like VO2max explains endurance performance to a large extent but psychological factors account for additional variance. In particular, one aspect of achievement motivation, namely perseverance, was associated with a better endurance performance. Endurance performance is explained by physiological (e.g. VO2max) and psychological (e.g. perseverance) factors VO2max explains young cyclists' endurance performance to a large extent Perseverance explained performance beyond the influence of VO2max [ABSTRACT FROM AUTHOR]

This study aimed to analyze the differences between clusters obtained by the acute fatigue effect following an ultra-endurance event on the internal and external load of cyclists. 26 volunteers participated in the study, divided into the experimental group (N = 18; height: 177 ± 8 cm; body mass: 78.6 ± 10.3 kg) and the control group (N = 8; height: 176 ± 10 cm; body mass: 78.0 ± 15.7 kg). The experimental group completed a 12 h non-stop cycling event. Jump height, lactate, plasma antioxidant capacity, pain perception and fatigue perception were measured before and after the event. Cyclists of the experimental group were classified taking into account their training characteristics (recreational vs. competitive) and conducting non-supervised Kmeans clustering. The differentiation of cyclists according to training characteristics resulted in a lower distance covered by recreational cyclists than competitive cyclists (279.4 ± 39.7 km vs. 371.0 ± 71.7 km; ES = 0.8; p < 0.01), although no differences were observed in the other variables between groups (p > 0.05). The clustering analysis resulted in two clusters. Cluster 2 suffered a greater jump height decrease (-3.3 ± 1.6 vs. 1.2 ± 0.8; ES = 0.8; p < 0.001) and increased pain and fatigue perception (ES = 0.5; p < 0.05) after the race than Cluster 1. In conclusion, countermovement jump and fatigue/pain perception can differentiate the fatigue produced by a cycling ultra-endurance event and therefore, these non-invasive measurements are useful in fatigue monitoring and recovery planning. [ABSTRACT FROM AUTHOR]

The poor cycling performance of Li-rich manganese-based (LMR) cathodes is one of the challenges that need to be urgently overcome. Enhancing the stability of the layered structure responsible for lithium-ion diffusion is an effective way to improve the cycling performance. Layered structures are mainly formed during the high-temperature solid-phase reaction, whereas the prolonged and constant-high-temperature calcination conditions in conventional calcination procedure may pose a threat to the layered structural stability. Thus, in order to optimize the formation environment of layered structures under high-temperature solid-phase reaction, we have designed suitable temperature-controlled strategies for each stage of layered structure formation, gradual maturation, and post-treatment, respectively, referred to as the 3-stage calcination strategy. This calcination strategy contributes to the formation of a more ordered and stable layered structure, which significantly improves the cycling performance of LMR cathodes (capacity retention rate of 85.2 % after 200 cycles at 1C). The shortening of the constant high temperature calcination time helps to further reduce the production cost of the batteries. The design concept of this work is to regulate the formation process of layered structures in stages, which provides inspiration for the efficient and controllable synthesis of electrode materials with excellent structural stability at low production cost. [Display omitted] • The 3-stage calcination strategy contributes to form a more stable layered structure. • The new calcination strategy helps to reduce Li/Ni mixing with oxygen vacancies. • The new calcination strategy helps to reduce production energy consumption. • The new calcination strategy endows the cathodes with excellent cycling stability. [ABSTRACT FROM AUTHOR]

Electrolyte decomposition and electrode corrosion stand as two primary side reactions in lithium‑oxygen (Li O 2) batteries during their discharge/charge cycles. In this work, a comprehensive Li O 2 battery model combining multi-step lithium peroxide (Li 2 O 2) formation, electrolyte decomposition, and electrode corrosion is proposed. Based on this model, the deposition behaviors and cycling performance of the Li O 2 battery under deep discharge/charge cycles are investigated. The stop of discharge is mainly ascribed to the loss of active surface area for the battery using tetraethylene glycol dimethyl ether (TEGDME) electrolyte, while both O 2 transport limitation and active surface area loss lead to the discharge termination for battery using dimethyl sulfoxide (DMSO) electrolyte. The incomplete decomposition of Li 2 O 2 and lithium carbonate (Li 2 CO 3) clogs electrode pores, leading to a continuous decline in the discharge capacity of the Li O 2 battery. For the TEGDME-based battery, the undecomposed Li 2 CO 3 gradually dominates the deposition with cycles, wherein electrode corrosion becomes the primary source of the undecomposed Li 2 CO 3 after 3 cycles. For the DMSO-based battery, undecomposed Li 2 O 2 is always a dominant trigger for battery discharge capacity degradation, although electrode corrosion remains a key contributor to Li 2 CO 3 generation. Despite the DMSO-based battery exhibiting lower rates of electrolyte decomposition and electrode corrosion, it demonstrates poorer cyclic performance than the TEGDME-based battery due to the generation of more toroidal Li 2 O 2. Moreover, when the charging cut-off voltage is reduced to 4.2 V, discharge capacity diminishes more rapidly due to the increased accumulation of undecomposed Li 2 O 2 , despite suppressed Li 2 CO 3 deposition. Finally, the results confirm that thick electrodes lead to deteriorating cycling performance, stemming from increased discharge/charge overpotential and extended discharge/charge times, thus intensifying the side reactions. • A multi-step discharge/charge Li-O 2 battery model involving electrolyte decomposition and electrode corrosion reactions is proposed. • Deposition/decomposition behaviors of Li 2 O 2 and Li 2 CO 3 from different reaction pathways with cycles are explored. • Mechanisms of discharge capacity degradation and discharge/charge failure under different conditions are revealed. [ABSTRACT FROM AUTHOR]

The flower-like structure NiO@C composite cathode materials show high discharge capacity and better cycling stability than NiO. [Display omitted] NiO possesses a high theoretical capacity, but its poor conductivity and significant volume changes during the redox process lead to severe electrochemical performance degradation, limiting its applications. In this study, flower-like structure NiO@C composite materials were synthesized via a hydrothermal method. The particle size of the material is approximately 10–16 μm, with a well-defined morphology of carbon material composite. Al-NiO@C batteries were constructed using NiO@C cathode and subjected to electrochemical performance testing. The initial discharge capacity of NiO@C composite material at a current density of 200 mA g−1 is 126 mA h/g, and even after 150 cycles, it retains a discharge specific capacity of 54 mA h/g. In contrast, the pure NiO exhibits an initial capacity of only 49 mA h/g, which decreases to 23 mA h/g after 150 cycles. The cycling stability of NiO@C material is significantly better than that of NiO alone. This improvement is attributed to the enhanced conductivity of NiO material by the addition of carbon material, which provides improved electron/ion transport properties. Additionally, the inclusion of carbon material helps alleviate the volume changes of NiO during the reaction process, thereby enhancing the overall electrochemical performance of Al-NiO batteries. [ABSTRACT FROM AUTHOR]

Tin phosphide (Sn x P y) is recognized as one of the most promising anode materials for lithium-ion batteries due to its exceptionally high theoretical capacity. However, its application is hampered by significant volume expansion during charge-discharge cycles and inferior electrical conductivity. Proper structural design plays a pivotal role in addressing these challenges, paving the way for high-performance anode materials. This study introduces a nitrogen-doped carbon-coated Sn 4 P 3 nanosphere with a core-shell structure, employing dopamine as the nitrogen source. This innovative approach, utilizing template removal and solid-phase phosphorization, results in both the core and shell acting as active materials, thereby enhancing the volumetric energy density of the electrode. The internal voids within the shell layer mitigate volume expansion during charge-discharge cycles, while the presence of the nitrogen-doped carbon layer maintains the material's stability throughout cycling and improves its electrical conductivity. Electrochemical performance tests confirm this material's outstanding energy storage capability, with an initial Coulombic efficiency reaching up to 73.6 %. Furthermore, it maintains a stable capacity of 585 mAh g−1 after 1200 cycles at a current density of 2 A g−1. This research offers a design paradigm for developing novel energy storage materials. [Display omitted] • Core-shelled Sn 4 P 3 improves the volumetric energy density. • The appropriate voids between shells accommodate volume expansion. • NxC layer on every shell enhances charges transport and structural integrity. • The composites show excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

The poor cycling performance of lithium-rich manganese-based (LMR) cathodes limits their practical applications. The stability of the layered structure is closely related to the cycling performance. The high-temperature solid-state reaction between transition metal oxides (TMOs) and lithium salts promotes the formation of the layered structure, which determines the quality of the layered structure. Considering the influence of physicochemical changes of the lithium salt on the formed layered structural stability, in this work, the calcination strategy includes a short period of holding time near the melting point of Li 2 CO 3 , referred to as the lithium salt preprocessing calcination strategy, which allows the molten Li 2 CO 3 to be fully contacted with TMOs at relatively low temperatures, alleviating the problem of Li in the thermal decomposition products of Li 2 CO 3 not easily further reacting with TMOs. Compared to the conventional calcination procedure, this new calcination strategy reduces the oxygen vacancy concentration as well as the relative Mn3+ content on the surface of the cathodes, which significantly improves the cycling performance. In addition, the shortening of the constant high temperature calcination time effectively reduces the production energy consumption, which provides a reference for the future efficient and low-cost synthesis of electrode materials with excellent cycling performance. [Display omitted] • Lithium salt preprocessing promotes a more adequate high temperature solid phase reaction. • Lithium salt preprocessing improves the stability of the layered structure. • This calcination strategy reduces the relative content of oxygen vacancies and Mn3+. • This calcination strategy reduces the energy consumption of cathode synthesis. [ABSTRACT FROM AUTHOR]

Practical applications of Li-metal anodes are limited by dendrite formation, Li loss, and poor reaction, resulting in a low Coulombic efficiency. In this study, we investigated the effects of island-shaped Ag atoms on the electrochemical behavior of Li-metal anodes. A Ag–Cu film was co-deposited through sputtering and subsequent annealing to anchor the Ag atoms with an island shape on a Cu substrate. The Ag target was co-sputtered with Cu with controlled atomic ratios in the Ag–Cu alloy. The sputtering thickness was set to 100 nm, and various annealing conditions were applied. The embedded island-shaped Ag atoms provided effective nucleation sites for Li deposition during the electrochemical nucleation of Li, increasing the nucleation density and spatial uniformity while decreasing the nucleation size and potential. Compact dendrite-free high-density Li deposition was achieved by annealing the Ag–Cu current collector (CC) at 600 °C. Under repetitive Li plating and stripping for 110 cycles at a current density of 0.5 mAcm−2 and capacity of 1 mAhcm−2, a high Coulombic efficiency of 98.5% was achieved. Conversely, the bare Cu CC had a life of up to 67 cycles under the same test conditions.

Numerous studies have been conducted in an attempt to discover cooling strategies that can be effective in improving exercise performance. However, the mechanism by which neck cooling relieves exercise-induced physiological stress and the optimal cooling temperature are unclear. This study aimed to investigate the effects of neck cooling at different temperatures during high-intensity cycling on body temperature, physiological variables, oxidant/antioxidant status, heat shock protein (HSP) 70 levels, and exercise performance in adolescent athletes. Seven well-trained male adolescent cyclists (age, 17.00 ± 0.76 years; athletic career, 3.86 ± 0.90 years) participated in three exercise trials involving three cooling regimens: control (CON), low-temperature (7 °C) neck cooling (LNC), and mixed-temperature (14 + 20 °C) neck cooling (MNC). The experimental condition used a cross-over design to minimize adaption to the repetitive cycling trials. Cycling consisted of a 20 km warm-up session and a two 2 km race session. Neck cooling at different temperatures was administered for 20 min during each rest period: after the warm-up, after the first 2 km race, and after the second 2 km race. Blood samples were taken to assess serum malondialdehyde (MDA), superoxide dismutase (SOD), and HSP70 levels. In addition, tympanic temperature (Tty), thermal sensation (TS), heart rate (HR), and the saturation of percutaneous oxygen (SpO2) were measured before, immediately after, and 24 h after exercise. As a measure of cycling performance, the race record and speed were measured in the first and second 2 km races. In all trials, Tty, TS, HR, MDA, SOD, and HSP70 levels significantly increased (p < 0.05), and SpO2 levels significantly decreased (p < 0.05). TS significantly decreased 24 h after exercise compared to that immediately after exercise in the LNC and MNC trials (p < 0.05). Serum HSP70 levels were significantly higher 24 h after exercise (0.87 ± 0.10 ng/mL) than immediately after exercise (0.79 ± 0.04 ng/mL) in the CON trial (p < 0.05). Twenty-four hours after exercise, the CON (0.87 ± 0.10 ng/mL) trial showed significantly higher serum HSP70 levels than the LNC (0.73 ± 0.01 ng/mL) trial (p < 0.05). There was no significant difference in cycling race record or speed between the trials (p > 0.05). Our findings suggest that neck cooling can induce a positive effect on thermal perception during recovery after cycling and that neck cooling at a relatively low temperature may be more effective in reducing exercise-induced HSP70 expression.

The supplementation of the nitric oxide precursor citrulline has been shown to boost athletic performance and recovery. Citrulline supplementation is appealing since it can be achieved legally through watermelon integration into the diet. However, the conditions where such supplementation improves exercise performance or physiological indexes related to exercise performance during cycling tests are confused and controversial since results differ according to the dosage, intake modality (chronic vs acute), the sport of interest, training status, and exercise intensity taken into account. Thus, an overview is needed to clarify the effects of citrulline during cycling tests. Moreover, the amount of watermelon required to achieve a minimum effective dosage of citrulline is unclear. This review analyses studies that investigated the effects of citrulline intake, taken acutely vs chronically, individually vs combined with other amino acids, and assessed through cycling tests in trained and recreationally active individuals. Previous research allows differentiating the citrulline effects during long-lasting submaximal intensity exercises, single sprints, multiple supramaximal sprints, as well as on the subjective feelings of discomfort associated with cycling exercise. Collectively, 6 g/day of citrulline supplementation for 7 days seems to improve sustained high-intensity laboratory time trials in both trained and recreationally active individuals. Causes may include physiological and psychological mechanisms associated with an improved energetic cost of cycling and a lower perception of fatigue. Performance improvements are also noticeable during single sprints in recreationally active individuals only as well as on the subjective perception of muscle fatigue and soreness during recovery. No improvements are noticeable on repeated sprints in trained individuals. This dosage of citrulline could be achievable through dietary watermelon supplementation (∼1.33 to 1.68 kg of "Tom Watson" and "Jubilee" fresh watermelon) without adding additional chemical synthesis-derived products. [ABSTRACT FROM AUTHOR]

The Zn-doped LNO cathode material was synthesized by sol-gel method. The effects of doping different amounts of Zn2+ on the properties of LNO were investigated. The results show that the sample doped with 2 mol% Zn (LNO-2Zn) delivers enhanced cycling performance and rate capability. The capacity retention rate for doped sample is 80.0% at 1 C rate after 100 cycles, which is higher than 74.8% for pristine LNO. Pristine LNO delivers a discharge capacity of only 48 mAh/g at 10C, which is much lower than that of 112.1 mAh/g of LNO-2Zn under the same condition. The introduction of Zn2+ ion reduces the degree of Li/Ni mixing, accelerates the lithium ion transfer, and slows down the harmful phase transition, thereby enhancing the electrochemical performance of LNO. [ABSTRACT FROM AUTHOR]

Anionic redox provides an effective way to overcome the capacity bottleneck of sodium‐ion batteries. A dominant role is played by the arrangement of alkali A and transition metal M in the NaxAyM1‐yO2 superstructure. Here, in situ X‐ray diffraction and ex situ 7Li nuclear magnetic resonance of P2 type Na0.6Li0.2Mn0.8O2 with ribbon‐ordered superstructure illustrate structural changes and explain the evolution of the electrochemical behavior of electrodes comprising this active mass, during cycling. Upon substitution of a small amount of manganese by iron, Na0.67Li0.2Mn0.73Fe0.07O2 is formed with a honeycomb‐ordered superstructure. Experimental characterizations and theoretical calculations elucidate the effect of iron on oxygen redox activity. The iron‐doped material considerably outperforms the undoped Na0.6Li0.2Mn0.8O2 as a cathode material for rechargeable Na‐ion batteries. This research reveals the effect of superstructure transformation on the electrochemical properties and offers a new perspective on element substitution in anionic redox active cathode materials. [ABSTRACT FROM AUTHOR]

The synthesized h-CoTiO 3 @rGO with large specific surface area and active sites effectively suppressed the shuttle effect of LiPSs through chemical absorption, and accelerated the redox reaction kinetics of LiPSs due to the high electrocatalytic ability. Meanwhile the hollow structure of h-CoTiO 3 provide sufficient space for sulfur loading, and uniform wrapped rGO in the h-CoTiO 3 @rGO/S cathode can ensure the excellent conductive network. In the above synergy of multiple merits, the battery with h-CoTiO 3 @rGO/S as cathode manifested a competitive cycling stability with an ultralow capacity fading of 0.0127 % per cycle after 500 cycles at 1C. Even the battery with high sulfur loading of 5.2 mg/cm2 still delivered a high area capacity of 5.02 mAh/cm2, which was competitive with the commercial Li-ion batteries. [Display omitted] The poor conductivity of sulfur, the shuttle effect and sluggish redox reaction kinetics of lithium polysulfides (LiPSs) are considered the main obstacles to the practical application of Lithium-sulfur (Li-S) batteries. Thus, it is urgent to design multifunctional host materials to eliminate these obstacles. Herein, we designed a hollow flower-like CoTiO 3 wrapped by reduced graphene oxide (h-CoTiO 3 @rGO) as sulfur host materials. The hollow structure of h-CoTiO 3 @rGO not only endows sufficient space for high sulfur loading, but also physically and chemically confines the shuttle effect of LiPSs through the formation of Co-S chemical bonding. The large specific surface area and excellent electrocatalytic ability of h-CoTiO 3 @rGO provide amounts of active sites to accelerate the redox reaction of LiPSs. Meanwhile, the conductive reduced graphene oxide (rGO) covered on the surface of CoTiO 3 microspheres offers an interconnected conductive network to support the fast electron/ion transfer. Profit from these merits, the battery employing the multifunctional h-CoTiO 3 @rGO as sulfur host exhibited excellent cycling stability with an ultralow capacity fading of 0.0127 % per cycle after 500 cycles at 1C. Even the battery with high sulfur loading of 5.2 mg/cm2 still delivered a high area capacity of 5.02 mAh/cm2, which was competitive with the commercial Li-ion batteries. Therefore, the competitive capacity and superior cycling stability suggest that the h-CoTiO 3 @rGO/S cathode is a potential candidate for high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Ni-rich layered oxide possesses a high theoretical capacity, high working voltage, and low cost; hence, categorized as a potential cathode material for high energy-density Li-ion batteries (LIBs). However, poor cycling performance, voltage fading, and thermal instability are some major issues that need to be addressed. Herein, a successful synthesis strategy is utilized to form a ternary oxide by sintering the hydroxide precursor at 500 °C for 6 h, followed by the lithiation of oxide under different sintering temperatures. The precursor pre-oxidation mitigates the cation mixing, removes residual lithium compounds, and enhances Li+ transportation. Moreover, the influence of sintering temperature on the electrochemical performance reveals that 750 °C for 15 h (NCAO-2) is the optimum temperature for oxide precursor. At this temperature, NCAO-2 holds enhanced cycling stability with retention of 89.8% after 100 cycles and 71% after 200 cycles. In contrast, the cathode synthesized with hydroxide precursor maintains 66.6% and 55.4% after 100th and 200th cycles at 1 C under the voltage range of 2.7–4.3 V. Furthermore, the rate capability, lithium diffusivity, and the thermal stability increase for oxide precursor NCAO-2. Consequently, the sintering of hydroxide precursors protects the particle from the inner to the outer surface. Hence, it is helpful to use oxide precursors to modify Ni-rich layered oxides further to attain high discharge capacity and enhanced cycling performance for their usage in high energy-density LIBs. [ABSTRACT FROM AUTHOR]

Dip coaters provide a compact device that can be used to obtain uniform and consistent coatings on a substrate. This article describes a less costly dip coater design with similar specifications to other dip coaters. The machine consists of a NEMA 23 stepper motor, touch screen display, and acrylic housing to protect the substrate from dust. The machine is programmed using Arduino IDE, allowing for easy changes to be made. The small size of the dip coater makes it ideal for use in labs. The majority of the components require no alterations after purchase, allowing for easy replacements and construction.

Niobium‐based tungsten bronze oxides have recently emerged as attractive fast‐charging anodes for lithium‐ion batteries (LIBs), owing to their structural openings and adjustability. However, electrodes with tungsten bronze structures usually suffer from structural variability induced by Li+ intercalation/de‐intercalation, leading to unsatisfactory cycling performance. To circumvent this limitation, a novel tetragonal tungsten bronze (TTB) structure, Ba3.4Nb10O28.4 (BNO), is developed as an anode material for LIBs with prominent cycling performance. An unprecedented cation‐vacancy ordered superstructure with a periodic distribution of active and inactive sites is revealed inside the BNO. Through multiple characterizations and theoretical studies, it is demonstrated that this superstructure can improve the lithium‐ion diffusion and disperse the structural strain induced by Li+‐intercalation to enable stable Li+‐storage. Benefiting from the superstructure‐induced local structural stability, both the BNO bulk and Ba3.4Nb10O28.4@C (BNO@C) microspheres can deliver >90% capacity retention after 250 cycles at 2 C and close to 90% capacity retention after 2000 cycles at 10 C. These results are of significant importance for establishing the structure–property relationship between the cation‐vacancy ordered superstructure and Li+‐storage performance, facilitating the rational design of stable tungsten bronze anodes. [ABSTRACT FROM AUTHOR]

Heteroatom-doped carbon can significantly improve the electrochemical performance of LiFePO4 cathodes, but it is limited by the complex preparation process and expensive dopants. A self-assembled S-doped LiFePO4@N/S-doped C coreâ€"shell structured composites were synthesized by a convenient solvothermal method are reported. The structure and the electrochemical performance of the composites were characterized. In the S-doped LiFePO4@N/S-doped C composites, the glucose-derived carbon microspheres were attached by LiFePO4/C particles to form secondary particles in the coreâ€"shell structure. The thioacetamide regulated the morphology of LiFePO4/C particles and provided N and S atoms to dope the composites. The S-doped LiFePO4@N/S-doped C composites delivered specific discharge capacities of 157.81 mAh gâˆ'1 at 0.1 C and 121.26 mAh gâˆ'1 at 5 C, and capacity retention of 99.88% after 100 charge/discharge cycles. The excellent electrochemical performance of the S-doped LiFePO4@N/S-doped C composites can be attributed to the synergism of thioacetamide and glucose. [ABSTRACT FROM AUTHOR]

Continued development of lithium-ion batteries is limited by the shortage of Li element. In this situation, the exploration of high-performance sodium-ion batteries is attracting much attention. In this experimental work, Na2/3Ni1/4Mn34O2 film cathode materials were fabricated by excimer laser deposition at different oxygen partial pressures. X-ray diffraction studies and field emission scanning electron microscopy revealed high c-axis orientation and uniform grain distribution, respectively, in the deposited films. Furthermore, after 30 cycles under a current density of 13 mA g−1, the film samples deposited at an oxygen partial pressure of 65 Pa exhibited a high capacity-retention of 91%. The film structure also had a large-current discharge performance, which makes practical applications possible. [ABSTRACT FROM AUTHOR]

To investigate the effect of solution pH on the adsorption and reuse of carbon-based composites, xerophilic and hydrophytic Alternanthera philoxeroides biochars (XAp-C and HAp-C) were loaded with 0%, 50%, and 100% dodecyl dimethyl betaine (BS-12)-modified bentonite (B, 50BSB, and 100BS-B) to form Ap-C/B, Ap-C/50BS-B, and Ap-C/100BS-B, respectively. Then, the isothermal adsorption and morphological changes of Cu2+ and cycling performance by the tested materials under different pH gradients were studied with XAp-C and HAp-C as the control. Results revealed the following. (1) The adsorption isotherms of Cu2+ for the tested materials were all consistent with the Langmuir model, and the maximum adsorption amount remained between 100.82-286.31 mmol/kg. Under the same conditions, the adsorption amount of XAp-C/BS-B was better than that of HAp-C/BS-B, and that of XAp-C/100BS-B was the best. (2) Thermodynamic parameter analysis showed that Cu2+ adsorption of the tested materials was a spontaneous, endothermic, and entropy-increasing reaction process. Kinetic fitting further showed that Cu2+ adsorption conformed to the pseudo-second-order kinetic model. (3) Within pH 2-6, the amount of Cu2+ adsorbed onto the tested materials all initially increased and then decreased, and the value at pH 5 was the best. (4) The Cu adsorbed onto the tested materials primarily existed in exchangeable and organic matter forms, followed by the carbonate form and then the Fe-Mn oxide form. With increased pH, Cu in carbonate form gradually transformed into the organic matter form, whereas Cu in exchangeable and Fe-Mn oxide forms remained basically unchanged. In summary, using XAp-C/100BS-B and adjusting the pH to 5 was the most favorable for Cu2+ adsorption, and the adsorption amount was 62.6% of the raw material after three times of regeneration. [ABSTRACT FROM AUTHOR]

LiNi0.8Co0.1Mn0.1O2 has been regarded as a promising cathode material due to its high discharge capacity, but it suffers from structural instability during the cycling process. Here, Mg2+ and Al3+ are co-doped in LiNi0.8Co0.1Mn0.1O2 to ameliorate the problem. The analysis results reveal that the dual doping can enlarge the Li+ diffusion channel, lower Li+/Ni2+ disorder, and depress the structural degradation during cycling. Therefore, the electrochemical performance of cathode material with Mg2+ and Al3+ dual doping has been effectively enhanced. In the voltage range of 2.8–4.3 V, the discharge capacity of NCM-MA is 138.8 mAh g−1 after 200 cycles at 1 C, which is 31 mAh g−1 higher than the pristine NCM. Prolonging the cycles to 450 times, the capacity retention is 12.5% higher than the pristine material. Besides, the NCM-MA delivers a high discharge capacity of 150.33 mAh g−1 at 5 C, due to the improvement of Li+ diffusion kinetics. [ABSTRACT FROM AUTHOR]

Abstract With the continuous expansion of the high‐purity hydrogen application range, the performance degradation of hydrogen storage alloy (HSA) caused by impurities has attracted widespread attention in producing pure hydrogen from biomass. In this study, the lanthanum‐rich mischmetal alloy's purification ability on hydrogen sulfide impurities and cycling performance were studied. The hydrogen with different concentrations of hydrogen sulfide was used to investigate the purification performance, which assumes the gas derived from biomass. Besides, a cycling experiment was designed to analyze cycling performance. The results show that the HSA could remove high concentrations of hydrogen sulfide entirely. It was also found that impurities of 1 ppm hydrogen sulfide had little effect on the HSA. With hydrogen sulfide concentrations of 100 ppm, the hydrogen storage capacity, absorption rate, and release rate were reduced, but they became a stable state from the second cycle. The performance degradation mechanism was analyzed by Energy Dispersive X‐Ray Spectroscopy (EDS) and X‐ray Photoelectron Spectroscopy (XPS​).

A nitrogen-doped carbon-coated NaCrO 2 cathode, designed to mitigate side reactions and enhance Na+ diffusion, demonstrates exceptional rate capability (95.6 mAh/g at 50C) and cycle stability (91.4% retention after 1000 cycles at 10C), advancing sodium-ion battery technology. [Display omitted] • The carbon and nitrogen coating layer can effectively reduce the surface impedance of the material and accelerate the diffusion of Na+. • The coating layer can inhibit the degradation of the crystal structure and suppress the electrode/electrolyte side reactions. • The nitrogen-doped carbon-coated NaCrO 2 cathode exhibits an outstanding capacity of 95.6mAh/g at a high discharge rate of 50C. We report nitrogen-doped carbon-coating to increase rate capability and cycle stability of NaCrO 2 cathode for sodium ion battery application. The nitrogen-doped carbon coating layer can effectively reduce electrode surface impedance and accelerate Na+ ion diffusion to allow high-rate performance. The coating layer can suppress the electrode/electrolyte side reactions and inhibit the degradation of NaCrO 2 , thereby markedly enhancing cathode cycling stability. Consequently, the NaCrO 2 cathode exhibits a specific capacity of 95.6mAh/g at 50 C and a capacity retention of 91.4 % after 1000 cycles at 10 C. [ABSTRACT FROM AUTHOR]

• Synthesis of Li 2 TiO 3 by an easy-to-industrialize solid-phase method. • Realize excellent ion selectivity and cycling stability of TiO 2 ·H 2 O adsorbents. • Different –OH groups play important roles in adsorption and desorption processes. How to effectively recover Li+ from liquid mineral brines with high Mg2+/Li+ ratio and low Li+ concentration is very significant and important for promoting the carbon peak and carbon neutrality plan valid. Therefore, taking the application merits and formation scheme into consideration, well-crystallized β-Li 2 TiO 3 precursors for obtaining TiO 2 ⋅H 2 O adsorbents were prepared through a classical solid-phase method under the optimized conditions. Interestingly, both Li+ desorption and titanium dissolution loss ratio of TiO 2 ⋅H 2 O adsorbents depend on the HCl concentration and delithiation temperature. The Li+ escaping routes from LTO precursors to TiO 2 ⋅H 2 O adsorbents is dramatically distinctive with that in the next adsorption/desorption cycles. Accordingly, as-prepared TiO 2 ⋅H 2 O adsorbents owns the high adsorption capacity up to 51.25 mg/g at 60 °C and low Ti-dissolution loss ratio around 1.08 %. The initial adsorption capacity of TiO 2 ⋅H 2 O adsorbents in real original oil–gas field brines containing 100 ppm Li+ is 20.14 mg/g. According to the structure–property relationship, formation and working mechanisms of TiO 2 ⋅H 2 O adsorbents was proposed. [ABSTRACT FROM AUTHOR]

Phosphate cathode materials have a stable and open backbone structure and are expected to be one of the ideal cathode materials for aqueous zinc ion batteries (ZIBs). In this work, a new compound Na 3 Ti 0.8 V 1.2 (PO 4) 3 is synthesised by sol-gel method and used as a cathode material for ZIBs. The battery delivered a reversible and stable capacity of 120.1 mA h g−1 over 100 cycles at 0.5 C. Impressively, the battery demonstrated exceptional cycling performance and outstanding rate performance, maintaining a capacity retention of 95.6 % after 1000 cycles at 5.0 C. It is demonstrated that the dissolution of V in water is effectively inhibited by partial Ti ion occupancy at the V site, which accelerates the ion diffusion rate and greatly improves the electrochemical performance. In this work, the charging and discharging process of NASICON structured Na 3 Ti 0.8 V 1.2 (PO 4) 3 cathode was investigated to show the mechanism of Na+ and Zn2+ co-doping. This discovery offers a novel phosphate cathode material for ZIBs, as well as a fresh approach to enhancing the specific capacity and stability of phosphate cathode materials. [Display omitted] [ABSTRACT FROM AUTHOR]

LiNi 0.65 Co 0.15 Mn 0.2 O 2 batteries have attracted more and more attention due to their high energy density. However, LiNi 0.65 Co 0.15 Mn 0.2 O 2 possesses adverse factors such as severe Li-Ni mixing and side reactions between active substance and electrolyte, which limits its electrochemical performance. Hence, we employed the SnO 2 surface coating method to enhance its performance. SnO 2 coating inhibits the direct contact between LiNi 0.65 Co 0.15 Mn 0.2 O 2 and the electrolyte, which reduces the lithium-nickel mixing, enlarges the lithium layer spacing, and contributes to the improvement of the specific capacity of discharge and the cycling performance. The electrochemical results indicate the optimal SnO 2 -coated LiNi 0.65 Co 0.15 Mn 0.2 O 2 show excellent cycling performance (85.0 % capacity retention for 100 cycles at 0.1 C) and multiplicative performance (124.1 mA·h·g−1 discharge specific capacity at 2 C). The paper highlights the SnO 2 cladding technology which provides an excellent research idea to improve lithium-ion batteries. [Display omitted] • NCM@x%SnO 2 anode materials were prepared by co-precipitation method. • SnO 2 capping increases Li diffusion rate by increasing Li+ layer spacing. • Improved material crystallinity by SnO 2 capping. • NCM@2 %SnO 2 has optimal cycling and multiplication performance. [ABSTRACT FROM AUTHOR]

• This review provided a comprehensive understanding of lithium-oxygen batteries in terms of electrodes catalyst design. • The significance of PGMs in the current perspective of energy storage is discussed. • The opportunities and challenges for PGMs-based electrodes are highlighted. • The prospects of PGMs-based electrode materials are recommended. In the realm of energy storage, the evolution of lithium-oxygen (Li-O 2) batteries has garnered substantial attention, owing to their potential to revolutionize electric vehicles. For a long time, ideas for sustainable development have positioned platinum group metals (PGMs) as potentially revolutionary, especially in the automotive industry. Intended to enhance Li-O 2 battery performance, PGMs are appealing due to their catalytic activities and this might be a big step forward for the electrification automotive industry and possibly pave the way for longer-lasting batteries used for reasons other than transportation. Therefore, this review explores progressions in PGMs-based electrocatalysts used as electrode materials for Li-O 2 batteries, starting with an overview of the Li-O 2 battery principle and its challenges. It then examines in detail the utilization of PGMs-based electrocatalysts as electrode materials for improving Li-O 2 battery performance. Finally, it addresses the remaining hurdles preventing the full integration of PGMs into battery technologies, offering insights into the current status and future possibilities for PGMs in Li-O 2 battery technology. [ABSTRACT FROM AUTHOR]

Postactivation-potentiation exercise with added whole-body vibration (WBV) has been suggested as a potential way to acutely improve sprint performance. In cycling, there are many competitions and situations where sprinting abilities are important. Purpose: To investigate the effect of adding WBV to warm-up procedures on subsequent cycle sprint performance. Methods: Eleven well-trained cyclists participated in the study. All cyclists performed a familiarization session before 2 separate test sessions in randomized order. Each session included a standardized warm-up followed by 1 of the following preconditioning exercises: 30 s of half-squats without WBV or 30 s of half-squats with WBV at 40 Hz. A 15-s Wingate sprint was performed 1 min after the preconditioning exercise. Results: Performing preconditioning exercise with WBV at 40 Hz resulted in superior peak power output compared with preconditioning exercise without WBV (1413 ± 257 W vs 1353 ± 213 W, P = .04) and a tendency toward superior mean power output during a 15-second all-out sprint (850 ± 119 W vs 828 ± 101 W, P = .08). Effect sizes showed a moderate practical effect of WBV vs no WBV on both peak and mean power output. Conclusions: Preconditioning exercise performed with WBV at 40 Hz seems to have a positive effect on cycling sprint performance in young well-trained cyclists. This suggests that athletes can incorporate body-loaded squats with WBV in preparations to specific sprint training to improve the quality of the sprint training and also to improve sprint performance in relevant competitions. [ABSTRACT FROM AUTHOR]

Cycling economy (CE), power output at maximal oxygen uptake (w...O2max), and anaerobic function (ie, sprinting ability) are considered the best physiological performance indicators in elite road cyclists. In addition to cardiovascular function, these physiological indicators are partly dictated by neuromuscular factors. One technique to improve neuromuscular function in athletes is through strength training. The aim of this study was to investigate the effect of a 20-wk maximal- and explosive-strength-training intervention on strength (maximal strength, explosive strength, and bike-specific explosive strength), w...O2max, CE, and body composition (body mass, fat and lean mass) in cyclists. Fifteen competitive road cyclists were divided into an intervention group (endurance training and strength training: n = 6; age, 38.0 ± 10.2 y; weight, 69.1 ± 3.6 kg; height, 1.77 ± 0.04 m) and a control group (endurance training only: n = 9; age, 34.8 ± 8.5 y; weight, 72.5 ± 7.2 kg; height, 1.78 ± 0.05 m). The intervention group strength-trained for 20 wk. Each participant completed 3 assessments: physiology (CE, w...O2max, power at 2 and 4 mmol/L blood lactate), strength (isometric midthigh pull, squat-jump height, and 6-s bike-sprint peak power), and body imposition (body mass, fat mass, overall leanness, and leg leanness). The results showed significant between- and within-group changes in the intervention group for maximal strength, bike-specific explosive strength, absolute w...O2max, body mass, overall leanness, and leg leanness at wk 20 (P < .05). The control group showed no significant within-group changes in measures of strength, physiology, or body composition. This study demonstrates that 20 wk of strength training can significantly improve maximal strength, bike-specific explosive strength, and absolute w...O2max in competitive road cyclists. [ABSTRACT FROM AUTHOR]

Following exercise-induced muscle damage (EIMD), masters athletes take longer to recover than younger athletes. The purpose of this study was to determine the effect of higher than recommended postexercise protein feedings on the recovery of knee extensor peak isometric torque (PIT), perceptions of recovery, and cycling time trial (TT) performance following EIMD in masters triathletes. Eight masters triathletes (52 ± 2 y, ...O2max, 51.8 ± 4.2 ml⋅kg-1⋅min-1) completed two trials separated by seven days in a randomized, double-blind, crossover study. Trials consisted of morning PIT testing and a 30-min downhill run followed by an eight-hour recovery. During recovery, a moderate (MPI; 0.3 g⋅kg-1⋅bolus-1) or high (0.6 g⋅kg-1⋅bolus-1) protein intake (HPI) was consumed in three bolus feedings at two hour intervals commencing immediately postexercise. PIT testing and a 7 kJ⋅kg-1 cycling TT were completed postintervention. Perceptions of recovery were assessed pre- and postexercise. The HPI did not significantly improve recovery compared with MPI (p > .05). However, comparison of within-treatment change shows the HPI provided a moderate beneficial effect (d = 0.66), attenuating the loss of afternoon PIT (-3.6%, d = 0.09) compared with the MPI (-8.6%, d = 0.24). The HPI provided a large beneficial effect (d = 0.83), reducing perceived fatigue over the eight-hour recovery (d = 1.25) compared with the MPI (d = 0.22). Despite these effects, cycling performance was unchanged (HPI = 2395 ± 297 s vs. MPI = 2369 ± 278 s; d = 0.09). In conclusion, doubling the recommended postexercise protein intake did not significantly improve recovery in masters athletes; however, HPI provided moderate to large beneficial effects on recovery that may be meaningful following EIMD. [ABSTRACT FROM AUTHOR]

Changes and relationships between cycling performance indicators following a one-year strength and conditioning training have not been totally clarified. The aims of this study are to investigate (i) the effect of a combined one-year strength and conditioning training programme on performance indicators and the possible relationships between these indicators, and (ii) the existence of possible endurance-functional-adaptive windows (EFAWs) linked to changes in muscular strength and body composition markers. Functional and lactate threshold power (FTP and LTP), maximal strength (1RM) and body composition (body mass index [BMI], body cell mass [BCM] and phase angle [PA]) were measured at the beginning and the end of a one-year strength and conditioning training programme of thirty cyclists. Correlations, differences, and predictive analysis were performed among parameters. Significant differences were found between pre- and post-conditioning programme results for FTP, LTP, 1RM (p < 0.0001) and BCM (p = 0.038). When expressed as power output (W), FTP and LTP were significantly correlated with 1RM (r = 0.36, p = 0.005 and r = 0.37, p = 0.004, respectively), body mass (r = 0.30 and p = 0.02), BCM (r = 0.68, p < 0.001) and PA (r = 0.42 and 0.39, respectively and p < 0.001). When expressed as W·kg-¹, these power thresholds were strongly correlated with body mass (r = -0.56 and -0.61, respectively) and BMI (r = -0.57 and -0.61 respectively) with p < 0.001. Predictive polynomial regressions revealed possible endurance and strength adaptation zones. The present findings indicated beneficial impacts of one-year strength and conditioning training on cycling performance indicators, confirmed the correlation between performance indicators, and suggested the existence of different EFAWs. Strategies aiming to improve performance should consider cyclist characteristics and performance goals to achieve EFAWs and thereby enhance cycling performance.

Li3V2(PO4)3 (LVP) is one of the candidates for high-energy-density cathode materials matching lithium metal batteries due to its high operating voltage and theoretical capacity. However, the inevitable side reactions of LVP with a traditional liquid-state electrolyte under high voltage, as well as the uncontrollable growth of lithium dendrites, worsen the cycling performance. Herein, a hybrid solid-state electrolyte is prepared by the confinement of a lithium-containing ionic liquid with a mesoporous SiO2 scaffold, and used for a LVP-cathode-based lithium metal battery. The solid-state electrolyte not only exhibits a high ionic conductivity of 3.14 × 10−4 S cm−1 at 30 °C and a wide electrochemical window of about 5 V, but also has good compatibility with the LVP cathode material. Moreover, the cell paired with a solid-state electrolyte exhibits good reversibility and can realize a stable operation at a voltage of up to 4.8 V, and the discharge capacity is well-maintained after 100 cycles, which demonstrates excellent capacity retention. As a contrast, the cell paired with a conventional liquid-state electrolyte shows only an 87.6% discharge capacity retention after 100 cycles. In addition, the effectiveness of a hybrid solid-state electrolyte in suppressing dendritic lithium is demonstrated. The work presents a possible choice for the use of a hybrid solid-state electrolyte compatible with high-performance cathode materials in lithium metal batteries.

The practical implementation of Zn-based flow batteries encounters the challenges associated with uneven deposition of Zn ions and undesirable side reactions. Here, a hybrid Zn-based electrolyte system composed of ZnBr 2 , ethylene glycol (EG), H 2 O and potassium gluconate (KGlu) is developed as anolyte to modulate the solvation structure and interface engineering for a sustainable Zn-based flow battery. The EG molecules could exclude water molecules outside the solvation structure, inhibiting the water-induced side reactions and Zn corrosion. Moreover, the incorporation of potassium gluconate constructs an artificial stable anionic interface for dendrite-free Zn deposition. Chemical stability and hydrogen evolution potential tests demonstrate that the activity of water molecules could be suppressed in the EG-containing hybrid electrolyte. Deposition morphologies and Zn//Zn symmetric flow battery tests also reveal that gluconate anions preferentially adsorbed on zinc anode could effectively facilitate uniform zinc deposition. As a result, the Zn-based flow battery with the proposed hybrid electrolyte delivers a stable cycling performance over 200 cycles and high reversibility with an average CE of over 97.4 % at 20 mA cm−2, exhibiting a peak power density of 103.2 mW cm−2. This work provides a universal electrolyte design strategy for realizing a sustainable Zn-based flow battery. • A hybrid electrolyte based on ZnBr 2 , EG, H 2 O and potassium gluconate is developed. • EG molecules exclude water molecules and inhibit water-induced side reactions. • Adsorbed gluconate anions facilitate stable Zn plating/stripping reactions. • Zn//Zn symmetric cell exhibits a stable cycling over 130 h at 20 mA cm−2. • Zinc-iron flow battery displays a relatively high cycling stability over 200 cycles. [ABSTRACT FROM AUTHOR]