Loss Of Capacity Research Articles

In-vehicle battery capacity fade: a follow-up study on six European regions

This work presents a follow up of previous case studies from the authors on the estimation of the in-vehicle battery capacity fade with performance-based models of Lithium-ion batteries applied to real-world vehicles’ activity data. The mobility pattern database is significantly enlarged compared to previous works from the authors, encompassing now six European regions, including 508,609 private vehicles which corresponds to 1.78 billion GPS records, 9.1 million trips and parking events and a total driven distance of 106.1 million kilometres. The capacity fade is derived at given years and mileage thresholds under different driving and recharging scenarios, supporting the concept of setting minimum performance requirements for traction batteries in future road transport policies. The vast majority of the considered scenarios do not lead to a battery capacity drop below 80% of its nominal value in less than five calendar years or 100,000 driven kilometres and below 70% in less than 8 years or 160,000 driven kilometres. The results of this work contributed to inform the new UN ECE Global Technical Regulation No. 22 on in-vehicle battery durability.

A fast charge algorithm for Li-ion battery for electric vehicles

The renewable solar energy industry and electric vehicle industry are today seeking for fast battery pack recharging methods to achieve higher performances, and fast energy recovery for energy storage systems (ESS) and for electric vehicles. The charge rate of batteries impacts directly the temperature which in turn impacts the capacity fade, thus it should be kept low to prevent the cells from warming up. This not only limits the charging rate but also puts us on a trade-off, a long lifetime or a fast recharge. In this study, we tried to achieve fast charging using a new charging method that combine two charging methods, without much deterring the capacity of the battery, in order to be able to maintain a long battery lifetime. Charging time of around 82 min was achieved for a 1.8 Ah battery. We compared our findings with the literature with known charging profiles.

Lithium insertion/extraction mechanism in Mg2Sn anode for lithium-ion batteries

Due to its high capacity and excellent voltage properties, the Mg2Sn intermetallic phase is considered a promising anode material for next-generation lithium-ion batteries. However, the rapid capacity loss with cycling presently limits the application of Mg2Sn-based anodes. In this work, the Mg2Sn intermetallic phase was synthesized via a conventional casting method, and mechanisms of lithium ions intercalation into Mg2Sn alloy anodes were systematically studied. Density functional theory (DFT) calculations and electrochemical analyses identified two pathways involving four electrochemical reactions for Li+ intercalation/extraction in the Mg2Sn phase. The first pathway involves the insertion reaction of lithium ions into the octahedral sites of the Mg2Sn face center cubic (FCC) matrix, whilst the second involves the substitution of Mg by Li ions (releasing Mg metal). Furthermore, ex-situ EIS analysis and DFT calculations verified that adjusting the cut-off voltage range could control the reaction pathways. Excessively high or low cut-off voltages adversely impact the stability of the Mg2Sn anode. At cut-off voltages between 0.1 and 1 V, Mg2Sn anodes show very good capacity retention (78 % after 50 cycles), benefiting from the minimized formation of metallic Mg and Sn phases.

Deciphering fundamental mechanism of different-type diluents on manipulating interfacial chemistry toward lithium metal anode

The growth of dendrites on lithium metal anode is troublesome because it induces irreversible capacity loss and safety hazards. Formulating localized high-concentration electrolytes (LHCEs) is an alternative solution to satisfy these challenges. However, the role of diluents in tailoring interfacial chemistry remains to be explicated. Herein, we decipher the direct relationship between different-type diluents and Li-coordinated solvation at the molecular scale. Compare to hydrofluoroethers (HFE), the “active” difluoro ethylene carbonate (DFEC) delivers a pronounced interaction with Li+ and 1, 2-dimethoxyethane (DME) molecule, resulting in a compressed but more accumulated aggregates (AGGs) solvation shell, assisting in the expected chemical nature of SEI with defluorination of DFEC. Consequently, DFEC-based LHCEs (D-LHCEs) realize a record-long lifespan over 3000 h with dendrite-free at 1 mA cm−2 and outstanding dendrite tolerance even under 3 mA cm−2 in symmetric cells. The assembled full cells with D-LHCEs outperform a superior capacity retention of ∼86.83 % with average CE of ∼99.42 % after 500 cycles at 0.5C and the remarkable cycling performance even under harsh conditions (including pouch cells or with controlled N/P of 1.8) in 4.45 V-level Li||LiCoO2 cells. This work highlights the decisive role of diluents in pursuing high-efficiency electrolytes for high-energy Li metal batteries.

Performance Analysis of Quad-Port UWB MIMO Antenna System for Sub-6 GHz 5G, WLAN and X Band Communications

A quad-port Multiple Input Multiple Output Antenna with high isolation is presented in this paper. The MIMO design is intended to receive Ultra-Wide Band response to target various wireless applications. The engineered model has 40 x 40 x 1.6 mm3 electrical dimensions. A single antenna achieves size compactness due to an appropriate inclusion of vertical and horizontal conductive strips. Additionally, a diagonal radiating strip is shaped and pooled with the patch geometry. A similar design is positioned orthogonally with each other to receive diversified performance. The four conducting ports are positioned with an appropriate minimum distance to lower down the possible mutual coupling. A partial ground plane having border geometry has been incorporated to receive the ultra-wide band response. An additional plus-sign shaped conducting strips are provided and united with ground lines for isolation enhancement. The MIMO system exhibits ultra-wide frequency response from 3.20 GHz to 13.40 GHz with adequate isolation below -20 dB and an impedance bandwidth of 10.20 GHz. The proposed structure provides an overall gain of 2 dBi having above 80% efficiency. The presented radiator exhibits excellent MIMO diversity response achieving minimal mutual coupling effect. The other output parameters such as envelope correlation coefficients<0.05, diversity gain of nearly 10 dB, mean effective gain<0.2 dB, and channel capacity loss<0.1 bits/sec/Hz were obtained. The proposed design has been simulated in High Frequency Structure Simulator (HFSS) software. The developed MIMO antenna has been analyzed through VNA N9912A. An encouraging correlation between the software generated and actual responses was observed. The strong agreement between actual results and software results shows the design potential for wireless communications. The highly isolated MIMO system registers its potential for sub-6 GHz 5G, WLAN, and X Band communications.

Thermal management lithium-ion battery for electric vehicles with using cold plate

Lithium-ion batteries are widely employed as the primary energy storage solution for electric vehicles (EVs). Effective thermal management of these batteries within EVs is important to ensure their safety, optimal performance, and longevity. Lithium-ion batteries are sensitive to fluctuations in temperature, and if not managed correctly, these temperature variations can lead to issues like overheating, reduced efficiency, and even safety risks. This study aims to investigate the effectiveness of a cooling method for a prismatic NMC battery used in electric vehicles. It emphasizes the significance of maintaining the battery's temperature within a specific range, typically between 15 °C and 35 °C, to prevent capacity loss and extend the battery's life. The design of the minichannel cold plate allows for precise thermal control with the 7 °C temperature difference. It efficiently absorbs heat generated during battery operation and releases it, preventing the battery from reaching undesirable temperature levels. Furthermore, the study underscores the importance of optimizing the contact area between the coolant and the battery stack for superior performance of the liquid cooling system. At higher discharge rates of the battery, a greater flow rate is required to achieve efficient cooling, with certain limitations due to the cooling system's efficiency. Overall, the study highlights the advantages of employing a liquid cooling system for proficient temperature regulation and effective heat dissipation in battery stacks for EVs.

High cycling stability of MnO2 cathode for aqueous Mg-ion batteries enabled by Fe doping

MnO2 has been widely investigated as a promising cathode material for aqueous magnesium-ion batteries, which, however, suffers from the severe capacity fading during charge/discharge cycling. In present work, we report that the doping of Fe in α-MnO2 enlarges the lattice and alleviates the Jahn–Teller distortions and thus accelerates the Mg2+ diffusion and strengthens the structural stability. Consequently, the capacity retention remarkably increases from 44.3 % to 85.2 % after 1000 cycles by Fe doping. Furthermore, it is found for the first time that Fe doping enables the co-insertion of H+ and Mg2+ in the tunnels of α-MnO2, which improves remarkably the specific capacity from 131.9 to 205.9 mA h g−1 at 0.1 A g−1.

Communication — The Impact of Co-solvent Selection for Dimethyl-2,5-dioxahexane carboxylate in Sodium Ion Batteries

Traditional linear carbonates including dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) were investigated as co-solvents for the dimethyl-2,5-dioxahexane carboxylate (DMOHC)-based electrolyte in Na0.97Ca0.03[Mn0.39Fe0.31Ni0.22Zn0.08]O2 (NCMFNZO)/hard carbon (HC) pouch cells. The EMC-containing cell displays excellent electrochemical performance, exhibiting only a 1.6 mAh irreversible capacity loss during 500 h of storage at 4 V and 40 °C, and maintaining over 80% capacity retention after 200 cycles up to 4 V at 40 °C. Severe gas evolution and Na plating issues are present in all the tested systems.

Effect of Operating Conditions on the Capacity of Vanadium Redox Flow Batteries

Abstract Vanadium redox flow batteries (VRFBs) present a viable solution to address the intermittent power output challenge associated with wind and solar energy generation. However, their development is impeded by their low energy density and high cost. To achieve the objective of cost reduction, it is crucial to optimize operating conditions, minimize capacity loss, and enhance battery performance. Through meticulous experimental analysis, this study thoroughly examines the impact of membrane thickness, current density, flow rate, and self-discharge on battery capacity. The experimental findings reveal that an increase in membrane thickness results in elevated resistance to proton transport, thereby weakening electrochemical reactions. Moreover, surpassing critical values for current density and flow rate also leads to a decrease in capacity. Prolonged shelving induces severe self-discharge reactions that accelerate deterioration of capacity fade. This research suggests that obtaining optimal operational parameters can effectively mitigate battery capacity fade.

Adaptation to ex vivo culture reduces human hematopoietic stem cell activity independently of cell cycle.

Loss of long-term hematopoietic stem cell (LT-HSC) function ex vivo hampers the success of clinical protocols reliant on culture. However, the kinetics and mechanisms by which this occurs remain incompletely characterized. Here, through time-resolved scRNA-Seq, matched in vivo functional analysis and the use of a reversible in vitro system of early G1 arrest, we define the sequence of transcriptional and functional events occurring during the first ex vivo division of human LT-HSCs. We demonstrate that the sharpest loss of LT-HSC repopulation capacity happens early on, between 6 and 24 hours of culture, before LT-HSCs commit to cell cycle progression. During this time window, LT-HSCs adapt to the culture environment, limiting global variability in gene expression and transiently upregulating gene networks involved in signaling and stress responses. From 24 hours, LT-HSC progression past early G1 contributes to the establishment of differentiation programmes in culture. However, contrary to current assumptions, we demonstrate that loss of HSC function ex vivo is independent of cell cycle progression. Finally, we show that targeting LT-HSC adaptation to culture by inhibiting early activation of JAK/STAT signaling improves HSC long-term repopulating function ex vivo. Collectively, our study demonstrates that controlling early LT-HSC adaptation to ex vivo culture, for example via JAK inhibition, is of critical importance to improve HSC gene therapy and expansion protocols.

Heterogeneous MoS2 Nanosheets on Porous TiO2 Nanofibers toward Fast and Reversible Sodium-Ion Storage.

2D layered molybdenum disulfide (MoS2) has garnered considerable attention as an attractive electrode material in sodium-ion batteries (SIBs), but sluggish mass transfer kinetic and capacity fading make it suffer from inferior cycle capability. Herein, hierarchical MoS2 nanosheets decorated porous TiO2 nanofibers (MoS2 NSs@TiO2 NFs) with rich oxygen vacancies are engineered by microemulsion electrospinning method and subsequent hydrothermal/heat treatment. The MoS2 NSs@TiO2 NFs improves ion/electron transport kinetic and long-term cycling performance through distinctive porous structure and heterogeneous component. Consequently, the electrode exhibits excellent long-term Na storage capacity (298.4mAhg-1 at 5Ag-1 over 1100 cycles and 235.6mAhg-1 at 10Ag-1 over 7200 cycles). Employing Na3V2(PO4)3 as cathode, the full cell maintains a desirable capacity of 269.6mAhg-1 over 700 cycles at 1.0Ag-1. The stepwise intercalation-conversion and insertion/extraction endows outstanding Na+ storage performance, which yields valuable insight into the advancement of fast-charging and long-cycle life SIBs anode materials.

Facile Fabrication of Large-Area CuO Flakes for Sodium-Ion Energy Storage Applications

CuO is recognized as a promising anode material for sodium-ion batteries because of its impressive theoretical capacity of 674 mAh g−1, derived from its multiple electron transfer capabilities. However, its practical application is hindered by slow reaction kinetics and rapid capacity loss caused by side reactions during discharge/charge cycles. In this work, we introduce an innovative approach to fabricating large-area CuO and CuO@Al2O3 flakes through a combination of magnetron sputtering, thermal oxidation, and atomic layer deposition techniques. The resultant 2D CuO flakes demonstrate excellent electrochemical properties with a high initial reversible specific capacity of 487 mAh g−1 and good cycling stability, which are attributable to their unique architectures and superior structural durability. Furthermore, when these CuO flakes are coated with an ultrathin Al2O3 layer, the integration of the 2D structures with outer nanocoating leads to significantly enhanced electrochemical properties. Notably, even after 70 rate testing cycles, the CuO@Al2O3 materials maintain a high capacity of 525 mAh g−1 at a current density of 50 mA g−1. Remarkably, at a higher current density of 2000 mA g−1, these materials still achieve a capacity of 220 mAh g−1. Moreover, after 200 cycles at a current density of 200 mA g−1, a high charge capacity of 319 mAh g−1 is sustained. In addition, a full cell consisting of a CuO@Al2O3 anode and a NaNi1/3Fe1/3Mn1/3O2 cathode is investigated, showcasing remarkable cycling performance. Our findings underscore the potential of these innovative flake-like architectures as electrode materials in high-performance sodium-ion batteries, paving the way for advancements in energy storage technologies.

Applying human-centered design to adapt the Jumpstart Guide for goals-of-care discussions in persons living with dementia.

Goals-of-care discussions (GOCD) are uncommon in persons living with dementia (PLWD) despite the likelihood of eventual loss of decisional capacity in the population. The Jumpstart Guide, an existing serious illness communication priming tool, can improve GOCD in certain populations, but has not previously been adapted for use among PLWD and their caregivers. Using human-centered design (HCD), we adapted the Jumpstart Guide for use with PLWD and their caregivers. We conducted qualitative interviews with clinicians and caregivers of PLWD. Six team members conducted qualitative rapid analysis of interviews leading to the development of summary templates and integrative matrices. Four iterations of the Jumpstart Guide led to the final version. Thirteen clinicians and 11 caregivers were interviewed. Interviews provided key insights into the unique barriers PLWD and their caregivers face during GOCD, including discomfort with accepting a dementia diagnosis and concern with using "serious illness" to describe dementia, as is commonly done in palliative care. Clinicians described differences in GOCD with PLWD compared to other serious illnesses, and the challenge of getting patients and families to think about future health states. Interviews led to Jumpstart Guide adaptations in the following domains: (1) format and structure, (2) content, and (3) specific language. Suggested changes included prioritizing naming a decision-maker, changing conversation prompts to improve accessibility and understandability, ensuring the Jumpstart Guide could be used with patients as well as their caregivers, and altering language to avoid references to "serious illness" and "abilities." Using HCD yielded valuable insights from clinicians and caregivers about the unique barriers to conducting GOCD among PLWD and their caregivers. These insights were used to adapt the Jumpstart Guide for use with PLWD and their caregivers, which is currently being tested in a pragmatic randomized controlled trial in outpatient clinics.

Mechanochemically Robust LiCoO2 with Ultrahigh Capacity and Prolonged Cyclability.

Pushing intercalation-type cathode materials to their theoretical capacity often suffers from fragile Li-deficient frameworks and severe lattice strain, leading to mechanical failure issues within the crystal structure and fast capacity fading. This is particularly pronounced in layered oxide cathodes because the intrinsic nature of their structures is susceptible to structural degradation with excessive Li extraction, which remains unsolved yet despite attempts involving elemental doping and surface coating strategies. Herein, we develop a mechanochemical strengthening strategy through gradient disordering structure to address these challenges and push the LiCoO2 layered cathode approaching the capacity limit (256 mAh g-1, up to 93% of Li utilization). This innovative approach also demonstrates exceptional cyclability and rate capability, as validated in practical Ah-level pouch full cells, surpassing the current performance benchmarks. Comprehensive characterizations with multiscale X-ray, electron diffraction and imaging techniques unveil that the gradient disordering structure notably diminishes the anisotropic lattice strain and exhibits high fatigue resistance, even under extreme delithiation states and harsh operating voltages. Consequently, our designed LiCoO2 cathode impedes the growth and propagation of particle cracks, and mitigates irreversible phase transitions. This work sheds light on promising directions towards next-generation high-energy-density battery materials through structural chemistry design. This article is protected by copyright. All rights reserved.

Unrecoverable lattice rotation governs structural degradation of single-crystalline cathodes.

Transitioning from polycrystalline to single-crystalline nickel-rich cathodes has garnered considerable attention in both academia and industry, driven by advantages of high tap density and enhanced mechanical properties. However, cathodes with high nickel content (>70%) suffer from substantial capacity degradation, which poses a challenge to their commercial viability. Leveraging multiscale spatial resolution diffraction and imaging techniques, we observe that lattice rotations occur universally in single-crystalline cathodes and play a pivotal role in the structure degradation. These lattice rotations prove unrecoverable and govern the accumulation of adverse lattice distortions over repeated cycles, contributing to structural and mechanical degradation and fast capacity fade. These findings bridge the previous knowledge gap that exists in the mechanistic link between fast performance failure and atomic-scale structure degradation.

Integration of Functional Groups to Enhance the Solubility and Stability of Viologen in Aqueous Organic Redox Flow Batteries.

The chemical stability and energy density of redox couples are crucial factors in enhancing the durability and cost competitiveness of aqueous flow batteries. This study proposed integrating functional groups to viologen anolyte to increase its solubility and, consequently, energy density and stability for prolonged performance. Specifically, sulfonate and ester groups were selectively incorporated at the nitrogen sites of viologen to enhance solubility, leveraging their asymmetry and double hydrophilicity. Furthermore, an alpha-methyl group was introduced between the bipyridine and ester groups to enhance the chemical stability by preventing stacking and dimerization that can lead to irreversible degradation. The modified viologen demonstrated a remarkable solubility of 3.0 M in deionized water, corresponding to a volumetric capacity of 80.404 Ah L-1. Additionally, the designed viologen exhibits outstanding retention of 92.4% after 200 cycles with a minimal capacity fading rate of 0.055% per cycle in a 0.1 M flow cell test.

Stabilizing Zinc Hexacyanoferrate Cathode by Low Contents of Cs Cations for Aqueous Zn-Ion Batteries.

Exploring cathode materials with excellent electrochemical performance is crucial for developing rechargeable aqueous zinc ion batteries (RAZIBs). Zinc hexacyanoferrate (ZnHCF), a promising candidate of cathode materials for RAZIBs, suffers from severe electrochemical instability issues. This work reports using low contents of alkaline metal cations as electrolyte additives to improve the cycle performance of ZnHCF. The cations with large sizes, particularly Cs+, changes the intercalation chemistry of ZnHCF in RAZIBs. During cycling, Cs+ cations co-inserted into ZnHCF stabilize the host structure. Meanwhile, a stable phase of CsZn[Fe(CN)6] forms on the ZnHCF cathode, suppressing the loss of active materials through dissolution. ZnHCF gradually converts to an electrochemically inert Zn-rich phase during long-term cycling in aqueous electrolyte, leading to irreversible capacity loss. Introducing Cs+ in the electrolyte inhibits this conversion reaction, resulting in the extended lifespan. Owing to these advantages, the capacity retention rate of ZnHCF/Zn full batteries increases from the original 7.0% to a high value of 54.6% in the electrolyte containing 0.03 M of Cs2SO4 after 300 cycles at 0.25 A∙g-1. This research provides an in-depth understanding of the electrochemical behavior of ZnHCF in aqueous zinc electrolyte, beneficial for further optimizing ZnHCF and other metal hexacyanoferrates.

Investigating Capacity Fade Mechanisms in Dual-Ion Mg-MClx Batteries

Abstract Mg batteries are a promising alternative to Li-based chemistries due to the high abundance, low cost, and high volumetric capacity of Mg relative to Li. Mg is also less prone to dendritic plating morphologies, promising safer operation. Mg plating and stripping is highly efficient in chloride-containing electrolytes; however, chloride is incompatible with many candidate cathode materials. In this work, we capitalize on the positive effect of chloride by using transition metal chloride cathodes with a focus on low cost, Earth-abundant metals. Both soluble and sparingly soluble chlorides show capacity fade upon cycling. Active material dissolution and subsequent crossover to the Mg anode are the primary drivers of capacity fade in highly soluble metal chloride cathodes. We hypothesize that incomplete conversion and chemical reduction by the Grignard-based electrolyte are major promoters of capacity fade in sparingly soluble metal chlorides. Modifications to the electrolyte can improve capacity retention, suggesting that future work in this system may yield low cost, high retention Mg-MClx batteries.

Adipose tissue as a linchpin of organismal ageing.

Ageing is a conserved biological process, modulated by intrinsic and extrinsic factors, that leads to changes in life expectancy. In humans, ageing is characterized by greatly increased prevalence of cardiometabolic disease, type 2 diabetes and disorders associated with impaired immune surveillance. Adipose tissue displays species-conserved, temporal changes with ageing, including redistribution from peripheral to central depots, loss of thermogenic capacity and expansion within the bone marrow. Adipose tissue is localized to discrete depots, and also diffusely distributed within multiple organs and tissues in direct proximity to specialized cells. Thus, through their potent endocrine properties, adipocytes are capable of modulating tissue and organ function throughout the body. In addition to adipocytes, multipotent progenitor/stem cells in adipose tissue play a crucial role in maintenance and repair of tissues throughout the lifetime. Adipose tissue may therefore be a central driver for organismal ageing and age-associated diseases. Here we review the features of adipose tissue during ageing, and discuss potential mechanisms by which these changes affect whole-body metabolism, immunity and longevity. We also explore the potential of adipose tissue-targeted therapies to ameliorate age-associated disease burdens.

Effect of Pea Shell Powder on Chemical, Sensory and Cooking Quality of Macaroni

Background: This research looks at putting pea shells, a byproduct of pea processing, into macaroni to improve nutrition and sustainability. It aims to emphasize the feasibility and benefits of utilizing pea shells in popular cuisines by investigating their nutritional profile and sensory characteristics. This study addresses waste and nutrient-deficient packaged foods by exploring the synergy of culinary innovation and sustainability. Utilizing phyto-nutrient-rich by-products from fruits and vegetables, it proposes enhancing products like macaroni, noodles, cakes, biscuits and soups for a healthier and more environmentally sustainable future. Methods: Studied how adding pea shell powder (10-30%) affected the chemical, sensory and cooking quality of four macaroni types, comparing them to a control group without pea shell powder. Result: Macaroni with pea shell powder excelled in color, appearance and taste. Type I (10%) showed superior sensory attributes, while Type III (30%) lagged, impacting overall acceptability. Furthermore, cooking performance analysis indicated that the inclusion of pea shell powder influenced cooking time (16.45-11.48 minutes), water absorption capacity (106-160 g/100 g) and cooking loss (14.3-4.89 g/100 g). The pea shell powder incorporation enhances the nutritional profile of macaroni, including significantly increased protein (8.57-12.64%), dietary fibers, minerals and decreased fat, carbohydrate and energy (370.4-206.66 kcal/100 g) content. Calcium, magnesium, iron and potassium contents were significantly higher in value-added macaroni than in the control. The quality analysis clearly showed that value addition improves the nutrition and taste of macaroni, which indicates potential premium macaroni products for the food industry and healthy alternatives for consumers.