Loss Of Capacity Research Articles

Recognition and Management of Postpartum Hemorrhage

Abstract Postpartum hemorrhage (PPH) is an obstetric emergency and refers to excessive blood loss after birth. Loss of blood volume and oxygen-carrying capacity may lead to maternal hypovolemia and hypotension resulting in tissue hypoxia, the onset of anaerobic metabolism, and multiorgan failure. If timely and appropriate action is not taken, cardiac arrest and maternal death may occur. If the amount of blood loss exceeds 500 mL following a vaginal birth or 1000 mL during or following a cesarean section, it is termed PPH. Similar to any other surgical hemorrhage, PPH is classified into primary PPH (occurs within 24 hours of birth) or secondary PPH (between 24 hours and 12 weeks postpartum). PPH is a major contributor to maternal deaths worldwide, and it is estimated that a person dies because of PPH approximately every 5 minutes. Therefore, measures should be directed at prevention and early detection of PPH with prompt management. The prevalence of PPH varies globally and is influenced by location, socioeconomic factors, and the availability and quality of health care. The World Health Organization reported that PPH accounts for a quarter of global maternal deaths. The Mothers and Babies Reducing Risks through Audits and Confidential Enquiries report from the United Kingdom (2023) highlighted that despite rare mortality due to hemorrhage, the number of people dying of obstetric hemorrhage is not decreasing, particularly among people with abnormally invasive placentation. Additionally, substandard care was found to be responsible for more than 50% of deaths due to PPH in the United Kingdom. Therefore, it is vital that adequate healthcare infrastructure, trained and competent healthcare professionals, and immediate access to resources, interventions, and multidisciplinary teams are essential both in well-resourced and resource-restrained healthcare systems. Healthcare professionals must identify the potential risk factors for PPH and initiate preventive measures whenever possible. Additionally, they must respond swiftly if PPH occurs and ensure a multidisciplinary, multilayered approach for a synchronized response to optimize outcomes. This review article emphasizes the etiopathogenesis, diagnosis, and management of PPH based on current scientific evidence as well as international best practice recommendations.

Regulating Interface Dipole Interaction between Ethers and Active Species toward Highly Stable Li-SPAN Batteries.

Sulfurized polyacrylonitrile (SPAN) is recognized as a promising organic cathode for long-lifespan lithium metal batteries. Nevertheless, the irreversible cleavage/formation of multiple sulfur-sulfur (S-S) bonds of SPAN within conventional ether-based electrolytes results in loss of active S species, severe capacity fading and shuttle effects. Herein, we propose a new electrolyte based on dipropyl ether (PE) solvent for Li-SPAN batteries. Benefiting from the particular chain-coordination structure and weak dipole interactions with Li+ and active species, the resulting electrolyte not only achieves low desolvation energy barrier and high Li+ transference number, but also displays stable electrolyte-electrode interface (EEI). Consequently, the full cells utilizing this electrolyte exhibit good cyclability, outstanding capacity retention and superior extreme-temperature (-50°C to 50 °C) performance. Furthermore, the Ah-scale pouch cell with lean electrolyte (2.5 g Ah-1) achieves record cycle stability with 96.5% capacity retention after 75 cycles, which deliver an initial specific energy density of 150 Wh kg-1 (based on the weight of the entire cell). Impressively, this strategy demonstrates universality in a series of organic electrodes employing with PE-based electrolytes. This work highlights the strategy for modulating the dipole interaction at EEI for long-lifespan Li-organic batteries at extreme conditions.

Regulating Interface Dipole Interaction between Ethers and Active Species toward Highly Stable Li‐SPAN Batteries

Sulfurized polyacrylonitrile (SPAN) is recognized as a promising organic cathode for long‐lifespan lithium metal batteries. Nevertheless, the irreversible cleavage/formation of multiple sulfur‐sulfur (S‐S) bonds of SPAN within conventional ether‐based electrolytes results in loss of active S species, severe capacity fading and shuttle effects. Herein, we propose a new electrolyte based on dipropyl ether (PE) solvent for Li‐SPAN batteries. Benefiting from the particular chain‐coordination structure and weak dipole interactions with Li+ and active species, the resulting electrolyte not only achieves low desolvation energy barrier and high Li+ transference number, but also displays stable electrolyte‐electrode interface (EEI). Consequently, the full cells utilizing this electrolyte exhibit good cyclability, outstanding capacity retention and superior extreme‐temperature (‐50°C to 50 °C) performance. Furthermore, the Ah‐scale pouch cell with lean electrolyte (2.5 g Ah‐1) achieves record cycle stability with 96.5% capacity retention after 75 cycles, which deliver an initial specific energy density of 150 Wh kg‐1 (based on the weight of the entire cell). Impressively, this strategy demonstrates universality in a series of organic electrodes employing with PE‐based electrolytes. This work highlights the strategy for modulating the dipole interaction at EEI for long‐lifespan Li‐organic batteries at extreme conditions.

Sodium-Rich, Co-Ni-Free P2-Layered Manganese Oxide Cathodes for Sodium-Ion Batteries.

The rapid capacity loss attributed to irreversible phase reactions and structural instability has consistently affected the development of P2-layered cathode materials. Moreover, the introduction of costly elements such as single or multiple dopants has failed to resolve the sustainability challenges in designing an optimal Mn-based layered oxide cathode. This study proposes a Co-Ni-free, poly-elemental doping strategy (Li, Mg, and Cu) combined with high sodium content for an Mn-based P2-layered cathode designed for Na+ ion storage. In situ X-ray diffraction analysis confirms the absence of P2 - O2 phase transitions during cycling for both NLMMC87 (Na0.87Li0.1Mg0.1Mn0.7Cu0.1O2) and NLMMC77 (Na0.77Li0.1Mg0.1Mn0.7Cu0.1O2). This can be attributed to the co-substitution of the electronegative Cu element and the stabilizing dopants Li and Mg, which suppress oxygen evolution. Simultaneously, the high sodium content within the host structure promotes high reversible capacity, enhances structural stability, and minimizes internal stress due to volume changes. Moreover, NLMMC87 demonstrates a reversible capacity of 167.9mA h g-1 at 0.1 C (97% Coulombic efficiency) and maintains excellent stability across various current rates. Further investigations into the practical application of NLMMC87 in a sodium full cell will be a critical step toward realizing an ideal cathode for sodium-ion batteries.

Polyoxovanadates as Effective Coating Materials for Layered Ni‐rich Oxide Cathodes in Liquid‐ and Solid‐State Batteries

Advanced coatings for improving the electro‐chemo‐mechanical stability of high‐capacity, layered Ni‐rich oxide cathode materials play an important role in modern battery technology. Vanadium‐based protective coatings are particularly promising owing to their ability to provide high ionic conductivity and their intrinsic robustness. In addition, diminishing or eliminating residual lithium through surface coating shows great promise in mitigating capacity losses and addressing associated challenges. Herein, we report on a strategic exploration of a facile coating approach for Ni‐rich LiNixCoyMn1−x−yO2 (NCM851005, 85% Ni content) utilizing polyoxovanadate. Specifically, TBA3H3[V10O28] was applied due to its solubility in non‐aqueous media, avoiding H2O‐induced side reactions and achieving a more uniform surface coverage. The cycling performance of NCM851005 before and after modification was tested in conventional Li‐ion cells, as well as in all‐solid‐state batteries with a lithium thiophosphate superionic electrolyte. Our findings highlight the potential of polyoxovanadate‐derived protective coatings for improving the cyclability of Ni‐rich cathodes.

The Impact of Lithium Anode Interface on Capacity Fade in Polymer Electrolyte-Based Solid-State Batteries

The Impact of Lithium Anode Interface on Capacity Fade in Polymer Electrolyte-Based Solid-State Batteries

Enhancing the potassium-ion storage performance of potassium manganese oxide cathode by single-element doping strategies

Layered manganese-based oxides are considered as ideal cathode materials for potassium-ion batteries (PIBs) due to their ease of synthesis and relatively large interlayer spacing. Nevertheless, the Jahn-Teller effect of Mn3+ and the irreversible phase transitions in high-voltage regions of layered manganese-based oxide leads to slow diffusion kinetics of potassium ions and severe capacity fading. Herein, a series of single-element doped manganese-based oxide cathodes K0.5Mn0.98X0.02O2 (X = Fe, Mg, Cu, Ti and Zn) are designed and investigated. The results demonstrate that trace doping with these elements stabilizes the layered structure of KMnO2 cathode materials, improves the diffusion coefficient of K+, and effectively suppresses the P3-O3-P3 phase transition in high-voltage regions. Among the doping-samples, the K0.5Mn0.98Fe0.02O2 exhibits outstanding reversible specific capacity of 127 mAh g−1 at a current density of 20 mA g−1. Meanwhile, K0.5Mn0.98Ti0.02O2 demonstrates exceptional cycling stability and rate capability, retaining 83.8 % of its initial capacity after 300 cycles at 200 mA g−1, and maintaining a high specific capacity close to 40 mAh g−1 even at 1000 mA g−1. This study validates the feasibility of trace element doping in enhancing the electrochemical performance of layered Mn-based cathode materials for PIBs.

Simulation and Optimization of Automated Guided Vehicle Charging Strategy for U-Shaped Automated Container Terminal Based on Improved Proximal Policy Optimization

As the decarbonization strategies of automated container terminals (ACTs) continue to advance, electrically powered Battery-Automated Guided Vehicles (B-AGVs) are being widely adopted in ACTs. The U-shaped ACT, as a novel layout, faces higher AGV energy consumption due to its deep yard characteristics. A key issue is how to adopt charging strategies suited to varying conditions to reduce the operational capacity loss caused by charging. This paper proposes a simulation-based optimization method for AGV charging strategies in U-shaped ACTs based on an improved Proximal Policy Optimization (PPO) algorithm. Firstly, Gated Recurrent Unit (GRU) structures are incorporated into the PPO to capture temporal correlations in state information. To effectively limit policy update magnitudes in the PPO, we improve the clipping function. Secondly, a simulation model is established by mimicking the operational process of the U-shaped ACTs. Lastly, iterative training of the proposed method is conducted based on the simulation model. The experimental results indicate that the proposed method converges faster than standard PPO and Deep Q-network (DQN). When comparing the proposed method-based charging threshold with a fixed charging threshold strategy across six different scenarios with varying charging rates, the proposed charging strategy demonstrates better adaptability to terminal condition variations in two-thirds of the scenarios.

Effect of Microstructure on Chemo-Mechanical Damage Evolution in Aluminum Foil Anodes for Lithium-Ion Batteries

Aluminum-based foil anodes could enable lithium-ion batteries with high energy density comparable to silicon and lithium metal. However, mechanical pulverization and lithium trapping within aluminum tend to cause capacity fading. The complex interplay between these damage modes is not well understood, as well as the role of microstructure on reaction front evolution. Here, we investigate aluminum foils with different compositions and processing conditions to understand how microstructure influences chemo-mechanical degradation. Backscattered electron imaging of ion-milled foil cross sections is used to visualize reaction front evolution and chemo-mechanical degradation. We find that the shape of the reaction front during lithiation is strongly affected by foil composition, defect distribution, and grain size, which, in turn, affects the evolution of chemo-mechanical damage within the foils. Furthermore, a key finding is that the extent of fracture upon delithiation is inversely related to lithium trapping, with foil compositions that exhibit uniform lithiation, and therefore, less fracturing showing greater lithium trapping. Nonreactive precipitate inclusions within alloy foils are also found to induce void formation. This work shows that material design strategies designed to overcome the inverse fracture-lithium trapping relationship could be useful for improving performance. Published by the American Physical Society 2024

Shear behaviour of continuous fibre-reinforced lightweight aggregate concrete beams

A series of shear tests on six fibre-reinforced lightweight aggregate concrete (FRLWAC) beams containing both steel and polypropylene fibres are presented in this paper. These beams were designed and cast with different boundary conditions, steel fibre contents, and shear-span-to-depth ratios (a/d). From the test programme, it was found that an addition of 0.5 % of steel fibre by volume significantly improved the shear behaviour of continuous FRLWAC beams and mitigated the concern of low shear resistance associated with lightweight concrete. The addition of steel fibre enhanced the direct strut strength of FRLWAC beams in shear and improved the efficacy of stirrups in transferring shear forces. The test results also suggested that continuity effect prevented sudden and complete loss of load-carrying capacity in FRLWAC beams failing in shear, although it did not significantly increase the shear-carrying capacity. A strut-and-tie model was proposed to predict the shear resistance of continuous FRLWAC beams. The contribution of steel fibre in enhancing the efficacy of compression struts and stirrups was considered in this model. This model was shown to be accurate in predicting the shear resistance of FRLWAC beams and was more accurate and reliable compared to available shear strength prediction provisions in different design codes. It also presents a viable alternative to a three-dimensional finite-element model for predicting the shear resistance of continuous FRLWAC beams.

“Dead Lithium” Formation and Mitigation Strategies in Anode‐Free Li‐Metal Batteries

AbstractThin lithium‐metal foil is a promising anode material for next‐generation batteries due to its high theoretical specific capacity and low negative potential. However, safety issues linked to dendrite growth, low‐capacity retention, and short cycle life pose significant challenges. Also, it has excess energy that must be minimized in order to reduce the battery costs. To limit excess lithium, practical lithium metal batteries need a negative‐to‐positive electrode ratio as close to 1 : 1 as possible, which can be achieved through limiting excess lithium or using an “anode‐free” metal battery design. However, both designs experience fast capacity fade due to the irreversible loss of active lithium in the cell, caused by the formation of the solid electrolyte interphase (SEI), dendrite formation and “dead lithium,” – refers to lithium that has lost its electronic connection to the anode electrode or current collector. The presence of dead lithium in batteries negatively affects their capacity and lifespan, while also raising internal resistance and generating heat. Additionally, dead lithium encourages the growth of lithium dendrites, which poses significant safety hazards. Within this fundamental review, we thoroughly address the phenomenon of dead lithium formation, assessing its origins, implications on battery performance, and possible strategies for mitigation. The transition towards environmentally friendly and high‐performance metal batteries could be accelerated by effectively tackling the challenge posed by dead lithium.

Dual-Wide Multi-Band (DWMB) four-port flexible MIMO antenna for on-body multiple wireless applications including high diversity performance.

The single-input-single-output technology experiences loss of data in the communication channel due to the receiving antenna undergoing fading of the signal impinged on it. Today's need is faster data transfer with multiple applications in the single antenna with multiple-identical radiating elements, leading to multiple-input-multiple-outputDWMB (MIMODWMB) technology. The MIMODWMB configuration with multi-band capability is the objective of the proposed work with applications ranging between microwave-millimeterWave bands. The four-port Dual-Wide Multi-Band (DWMB) MIMODWMB antenna radiating electro-magnetic-energy is proposed, which generates measured bandwidths of 7.27GHz-34.32GHz (Band 1) and 46.54GHz-71.52GHz (Band 2) including applications Up-link/Down-link Satellite System, X-Band, Ku-Band, ISM 24.0GHz (24.0GHz-24.25GHz), 24.0GHz UWB Band (21.65GHz-26.65GHz), n258, n257/n261 and n263 V-band. The proposed antenna technology is printed on Rogers's low permittivity substrate with a hexagon patch etched with dual merged-elliptical slot and three identical circular slots to achieve high impedance matching for Band 1. The partial-ground is etched by a rectangular slot for better impedance matching, and two-thin-etched rectangular slits generate 60.0GHz Band 2. The thin substrate, thickness 0.254mm, is utilized for flexible applications without compromising the operation of dual wide bandwidths. The flexible antenna is also subjected to analysis of Specific-Absorption-Rate (SAR) analysis at key frequencies within both the bands and found to be within the standard limit of 1.60W/Kg for 1g of the human tissue model and corresponds to 1.01W/Kg at 10.0GHz, 0.280W/Kg at 15.0GHz, 0.475W/Kg at 26.0GHz, 0.588W/Kg at 28.0GHz & 0.301W/Kg at 60.0GHz. The high diversity performance with Envelope Correlation Coefficient<0.50, Diversity Gain≈10.0dB, Total Active Reflection Coefficent<0dB, Channel Capacity Loss<0.40b/s/Hz and multi-band capability for mobile users make the proposed work suitable for flexible on-body applications in a wireless environment. The proposed work MIMODWMB antenna offers advantages such as reduced size (20mm×24mm: 0.61λ0×0.74λ0 at λ0 = 7.27GHz) and a wide range of impedance bandwidths, which are useful for several applications. Also, due to the flexible nature of the design, they can be used for future on-body wearable applications.

Evaluation of overstrength-based interaction checks for columns in steel moment frames

Current design guidelines in the United States require a check for only column axial force under overstrength seismic loads for capacity-designed steel moment frames. A study is presented to examine the implications of this guidance, which disregards the column interaction check (including both axial force and moment) under overstrength seismic loads. A set of thirteen steel moment frames are designed using multiple rules that apply and disregard overstrength, drift, and cross-sectional compactness checks in various combinations. The frames are subjected to a suite of simulations including linear elastic, nonlinear static pushover, nonlinear response history, and continuum finite element simulations that are able to represent a range of physical behavior modes in the columns including interactive nonlinear geometric instabilities that could trigger loss of the load carrying capacity of the member. The simulations indicate no significant distinction between the seismic performance of steel moment resisting frames designed as per current code-based provisions (i.e., disregarding the column interaction check for overstrength seismic loads), and those designed with the use of the interaction check, with each providing acceptable response without failure. The simulations also indicate that design checks for drift and cross-sectional compactness play a significant role ensuring acceptable response, providing additional margin of safety beyond the member strength checks.

Adsorptive behavior of Rhodamine B dye over hierarchical N-doped carbons from hexamine-based complexes: Equilibrium and kinetics

Pollution from water-soluble dyes is a common issue due to high toxicity and diffiulty in degradation, and its effectively removal is critical for human health and sustainability. In this work, N-doped hierarchical carbons were derived by facile pyrolysis of Co-including hexamine-based complex using glucose as a cross-linker, showing high removal ability using Rhodamine B (RhB) as a model dye. Porous architecture and N-coordination can be easily altered by pyrolysis temperature, where the GNC-900 sample obtained at 900 °C exhibits the best removal ability even outperforming several classical carbons under equal conditions, owing to synergistic effects from large surface areas, high ratio of pyrrolic-N, enhanced interaction between RhB molecules and pore walls, and possible Co-Nx active sites. Adsorptive behaviour is better fitted by pseudo-second-order kinetic model, and the maximum RhB capacity over GNC-900 determined by Langmuir model is highly up to 400.1 mg/g, following mechanisms of pore filling, π-π conjugation, electrostatic, surface complexation and H-bonding. Thermodynamics indicate that RhB removal is exothermic and spontaneous process. Moreover, GNC-900 can be readily regenerated using ethanol and reused at least six times without notable loss in capacity. This novel method facilitates synthesis of N-doped carbons from metal-based complexes, exhibiting high efficiency as adsorbents for water remediation.

Intrinsic capacity loss rates and protective factors among individuals aged 80 years and older in Chinese nursing homes: A latent class analysis

Prior to this cross-sectional study, the intrinsic capacity (IC) loss rates and protective factors in nursing homes for individuals aged 80 and older remained unexplored. Analysing 434 participants, this study found 86.9 % of individuals experienced the loss of at least one IC domain, with detailed losses in locomotion, vision, vitality, hearing, psychological, and cognitive capacities at rates of 83.2 %, 52.8 %, 50.9 %, 46.5 %, 44.9 %, and 44.0 %, respectively. Following latent class analysis (LCA), five distinct IC impairment patterns were noted, with locomotor impairment emerging as a central component across most classes. IC protective factors for persons aged 80 years and older included financial stability, being male or younger within the cohort, junior high school or higher education, being married, no smoking history, manageable comorbidity levels, minimal medication use, good sleep, and not using assistive devices. Based on these five classes, this study provides a potential practical framework alongside recommendations for IC care strategies in the oldest-old, emphasising the importance of locomotor function in maintaining the overall IC.

Blackcurrant Supplementation and Habitual Physical Activity Enhance Functional Capacity and Quality of Life in Previously Sedentary Older Women.

Loss of functional capacity negatively impacts the quality of life in older adults. This single-site randomized controlled study examined whether short- (one week) and long-term (three months) blackcurrant supplementations combined with habitual physical activity would improve functional capacity and quality of life in previously sedentary older women. Thirty sedentary, healthy older women were randomly assigned to receive blackcurrant supplementation (400 mg of blackcurrant extract) (Polyphenol group, n=15; 74.2±10.0 years) or no supplementation (capsules of 400 mg of corn flour) (Placebo group, n=15; 72.8±8.7 years). Each group consumed two capsules daily for one week and three months, with a washout period of one week between the two phases. The polyphenol group was required to increase habitual activity levels. Participants underwent a functional capacity assessment consisting of a sixminute walk, sit-to-stand test, Berg balance scale measurement and quality of life evaluation with the Scale of Life Satisfaction Index (LSI) at the start, after one week, and after three months of supplementation. Walking distance and time to sit-to-stand improved by 2.5% (p=0.005) and 7.5% (p=0.005), respectively, after one week in the polyphenol group. After 3 months, walking distance in the six-minute walk test increased by 12.3% (p=0.001) while the time to sit-to-stand decreased by 16% (p=0.002) in the polyphenol compared to placebo group, respectively. No differences in Berg balance scale were observed. Quality of life, indexed by LSI, improved by 39% (p=0.001) in the polyphenol compared to the placebo group. Blackcurrant supplementation, combined with habitual activity, may enhance functional capacity and quality of life in older women, offering a potential strategy to maintain independence. However, future studies should address longer durations to validate these findings.

Enhancing the bending strength, load-carrying capacity and material efficiency of aspen and black alder plywood through thermo-mechanical densification of face veneers

Many research papers highlight the positive impact of wood densification on mechanical properties of solid wood as well as wood veneers. Previous experimental studies comparing densified to non-densified wood materials of the same thickness consistently demonstrated higher strength properties in bending for densified materials. However, these studies often overlooked an important comparison: the strength and load-carrying capacity of non-densified wood material to its densified state, in which the thickness is reduced and thus the material’s moment of inertia. The current study, aims to address this gap for plywood made from low-quality, underutilized hardwood species, encompassing both non-densified and densified veneers. Additionally, these plywood panels are compared with high-quality birch plywood. Plywood samples made from common aspen (Populus tremula L.) and black alder (Alnus glutinosa L.) species, incorporating densified veneers, are compared to conventional silver birch (Betula pendula Roth.) plywood. The study also considers material utilization efficiency. Results showed that plywood made from non-densified aspen and black alder veneers exhibited comparable strength to standard birch plywood, positioning them as competitive alternatives to high-quality wood species. While densified black alder veneers increased strength in average from 83.6 MPa to 126.3 MPa, a loss in load-carrying capacity was observed from 1930 N to 1637 N due to reduced thickness and moment of inertia.

Enhancing fire performance of glulam beams through thermal treatment, inorganic impregnation, and densification techniques

The present research investigates a novel, environmentally benign modification method for improving the fire performance of Chinese fir that grows quickly and at low density. This wood is known for its susceptibility to burning and rapid loss of load-bearing capacity in fires. After thermal treatment, inorganic impregnation, and densification, Chinese fir was utilized as the fire-exposure surface for glulam beams. Three sides of full-size members were subjected to fire tests lasting 60 and 90 minutes. Considering the gluelines' thermal conductivity, the improved glulam beams' fire performance was thoroughly evaluated using the finite element program ABAQUS. The study found that the composite modification approach enhanced the weight percentage and mass density of the wood laminates by 32.53 % and 67.87 %, respectively. After 60 min of fire exposure, the charring rates on the exposed surface of the members with the modified laminates were 13.5 % and 27.8 % lower than those of standard glulam beams, indicating a considerable improvement in fire resistance. Greater post-fire residual cross-sectional area and improved fire resistance performance were correlated with an increase in the quantity of modified laminates. The composite modified glulam beams showed a noticeable temperature gradient, which was explained by higher density and specific heat capacity and consequently improved overall fire resistance, according to finite element analysis. The corner effect on the glulam beam cross-section became more evident with prolonged heating, while the gluelines had minimal impact on overall heat transfer.

Enhanced cyclability of O3-NaNi0.33Fe0.31Mn0.36O2 by Mg and Cu synergistic doping with strengthened Mn[sbnd]O bonds

Among some practical O3-type layered oxide cathodes, NaNi1/3Fe1/3Mn1/3O2 (NFM) features a high specific capacity and moderate cyclability. However, sluggish Na+ transfer kinetics, low structural stability, and rapid capacity loss during long-term cycling, are still posing a challenge to commercial applications of this material. In this work, we propose a Mg and Cu co-doped O3-type NaMg0.02Cu0.02Ni0.33Fe0.27Mn0.36O2 (MC-NFM) with a stable structure and good cycling stability. It was found that the MnO bonds in MC-NFM are obviously reinforced by synergistic doping with small amounts of Mg and Cu, leading to enhanced structural robustness, decreased Na+ migration barrier, and delayed O3-P3 phase transition. As a result, longer cycle life and enhanced rate performance are achieved. MC-NFM can yield a specific capacity of 142.1 mAh g−1 at 0.1C and 116.0 mAh g−1 at 5C, and maintain 83.6 % of its initial capacity after 400 cycles at 1C. This work provides a promising design of O3-type cathode for sodium-ion batteries.

Unveiling electrochemical insights of lithium manganese oxide cathodes from manganese ore for enhanced lithium-ion battery performance

Implementing manganese-based electrode materials in lithium-ion batteries (LIBs) faces several challenges due to the low grade of manganese ore, which necessitates multiple purification and transformation steps before acquiring battery-grade electrode materials, increasing costs. At present, most Lithium Manganese Oxide (LMO) materials are synthesized using electrolytic manganese dioxide, and the development of new processes, such as hydrometallurgical processes is important for achieving a cost-effective synthesis of LMO materials. In this work, we develop a full synthesis process of LMO materials from manganese ore, through acid leaching, forming manganese sulfate monohydrate (MnSO4·H2O), an optimized thermal decomposition (at 900, 950 or 1000 °C) producing different Mn3O4 materials and a solid-state reaction, achieving the synthesis of LMO. The latter was used as a cathode material for LIB exhibiting a specific capacity comparable to the state-of-the-art LMO cathode with a remarkable cycling stability of 800 cycles with <20 % in capacity loss. These performances were attributed to the excellent redox reversibility of the LMO cathode, characterized by voltammetry and in operando and in situ characterization by Raman and XRD.