Stationary Energy Storage Systems Research Articles

Mapping the flow: Knowledge development and diffusion in the global innovation system of flow battery technology

Redox flow batteries (RFB) are receiving increasing attention as promising stationary energy storage systems. However, while first innovation activities in this technological field date back to the 1950s, the commercialization and diffusion rates of RFB technology have remained limited. Apart from technological challenges, the lack of a functioning innovation system is one of the main barriers to mainstream this technology. Here, we carried out a comprehensive bibliometric analysis of the RFB research field to shed systematic light on a core aspect of innovation systems - the production of knowledge. Based on the analysis of 4,872 papers published in the years 1981–2021, we reveal developments over time, describe the geographical distribution of research activities, and explore collaboration networks as well as emerging lines of research. Overall, our study allows for strengthening the RFB innovation system by providing the foundation for aligning a scattered research field, identifying needs for technology development, and fostering collaboration and synergy creation.

Optimal allocation of autonomous PV-powered fast charging stations for electrified transportation considering traffic dynamics

In response to the imperative to reduce greenhouse gas emissions, global efforts are focusing on electrifying transportation and adopting renewable energy sources. This necessitates establishing reliable fast-charging stations (FCSs) for the widespread integration of electric vehicles (EVs). Indeed, the arbitrary distribution of FCSs can detrimentally affect the efficiency of traffic movement. Thus, this paper presents a planning methodology aimed at optimizing the allocation of FCSs within large-scale transportation networks. The energy system proposed includes an autonomous photovoltaic (PV)-powered FCS based on a DC microgrid, supplemented by a stationary battery energy storage system for backup power. The behavior of EVs within the traffic flow is modeled using a realistic traffic simulation software called Dynamic Network Assignment Simulation for Advanced Road Telematics (DYNASMAT). The conflicting objectives of minimizing total annual costs and EV average waiting time at stations are addressed through multi-objective optimization. To solve this optimization problem, the GAMS software is employed. A transportation network with 92 nodes and 284 links is utilized to test the proposed approach. The proposed autonomous PV-powered FCS is compared with Natural Gas-fired Distributed Generators (NGDG)-powered FCS. The simulation results show that while the NGDG-powered FCS exhibits higher emissions, the autonomous PV-powered equivalent operates emission-free. However, the annual cost of the autonomous PV-powered FCS is higher than that of the NGDG-powered FCS.

(Invited) Organosilicon Coatings Made By a Cold Plasma Processes at Atmospheric Pressure for Electrochemical Applications

Cell manufacturing is estimated to account for up to 40% of battery-industry and the related market will grow 14.1% in the next five years (108.4 B$ in 2019). In this context, high-power and stationary large-scale energy storage systems, such as lithium-ion batteries (LiBs), will be essential to make electricity quickly accessible to the power grid. This is particularly true when it comes to power plants located in remote areas or the use of renewable energy sources. Despite their advantages, commercial LiBs are today limited by their environmental and safety hazards. These limitations lead researchers around the world to discover and employ new technologies for safe recycling operations and a better control of the cycling processes. Currently, works are focused on the development of new advanced materials, composite design as well as advanced interfacial layers. In this context, surface modification by cold plasma is one of the most promising solutions to control and modify charge transport mechanisms at the interfaces. Although, the synthesis of nano-layers made by plasma at atmospheric pressure has already received a lot of interest, their use to modify electrochemical devices, such as electrochemical cells remain limited. In this work, the synthesis of organosilicon coatings on composite conductive layers by atmospheric pressure DBD is studied in detail. The influence of different organosilicon molecules has been analysed to highlight the effect of the growth mode as well as chemical functionalities on the operation of the final electrochemical device. The physical and chemical modifications of plasma on the conductive layer as well as the water stability of the coatings were investigated by ATR-FTIR, XRD, SEM and contact angle. Figure 1

Electrolyte and Cutoff Potential Effects on Cycle Life of Li4Ti5O12/LiNi0.9Mn0.1O2 Batteries for Behind-the-Meter Storage Applications

Behind-the-Meter Storage (BTMS) is a stationary battery energy storage system that is connected to the electrical distribution system on the customer’s side of the utility’s service meter. BTMS systems are used to store electrical energy from the grid as well as inconstant, renewable energy, such as local solar and wind generation. A successful BTMS system will allow the customer to pair their energy generation and storage to optimize electrical consumption from the grid, improving reliability and minimizing cost. For BTMS applications, batteries must be designed and optimized with different set of criteria from other leading segments of the Li-ion battery market, like transportation, due the system being stationary and proximal to the residential or commercial building it’s benefitting. BTMS applications prioritize safety, cost (low/no-critical materials), reliability (20-year calendar life), and durability (10,000 cycle life), while having the ability to (minimally) compromise energy density and rate capability.Lithium titanate (Li4Ti5O12, LTO) is a promising anode candidate for BTMS applications due to its high safety and capacity retention, while maintaining a reasonable 160 mAhg-1 reversable capacity and composition of relatively abundant materials. (1) Specifically, LTO has a high working voltage which helps to prevent Li dendrite formation, improving safety. Furthermore, LTO also has negligible lithiation-based volume change, leading to less mechanical pulverization, or loss of active material, upon cycling. For the cathode, materials with little or no Co are of high interest due to the high cost and low abundance of Co. LiMn2O4 (LMO) has been paired with LTO for BTMS applications in the past due to its safety, low cost (abundancy), and reasonably high operating voltage. (2-4) However, the low capacity of LMO limits energy density and specific energy. While not the highest priority for BTMS applications, increasing energy density will enable deployment in space constrained BTMS applications and decrease total cost. LiNi0.9Mn0.1O2 (LNMO) is a recently developed material with promise due to its high operating voltage and relatively low price. (5) However, Ni-rich layered oxides, including LNMO, tend to struggle with capacity retention during high-voltage cycling due to mechanical pulverization, irreversible phase transitions, and unstable solid-electrolyte interphase.The study presented here focuses on building an understanding of how electrolyte solvent and varied cutoff potentials will impact the cycle life of LTO/LNMO cells. Specifically, a comparison is provided between ethylene carbonate (EC), ethyl methyl carbonate (EMC), fluoroethylene carbonate (FEC), and Gen2 electrolyte solvents with 1M Lithium hexafluorophosphate (LiPF6) salt, cycling to two upper termination potentials, 2.6V and 2.7V. Electrochemical testing and diagnostics (e.g., differential capacity analysis, area specific impedance, constant voltage hold, and rate capability) and post-mortem characterization will be used to understand the aging behavior and failure mechanisms of the 8 cell combinations (four electrolytes and two voltage cutoffs). Cells with FEC electrolyte showed a lower initial capacity compared to cells with Gen2, EMC, and EC cycling at both voltages; however, the cells with FEC showed consistent trends in capacity retention with 2.6V and 2.7V termination potentials, while the cells with the other electrolytes showed much higher rates of capacity loss when cycling to the higher voltage. These results indicate that FEC may play a role in improving durability of high-voltage, Ni-rich electrode systems for use in high-cycle applications, such as BTMS.This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding was provided by the U.S. Department of Energy's Vehicle Technologies Office under the Behind-the-Meter Storage (BTMS) Consortium directed by Samuel Gillard and managed by Anthony Burrell. The electrodes used in this manuscript are from Argonne's Cell Analysis, Modeling and Prototyping (CAMP) Facility, which is fully supported by the DOE Vehicle Technologies Office (VTO). The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.

Long-Term Calendar Aging across Commercial Lithium-Ion Cell Chemistries - Part II: Modeling and Early Prediction

Lithium-ion (Li-ion) batteries are widely used in applications such as mobility, stationary grid systems, and various consumer and commercial systems. In electric vehicles (EVs), batteries often remain idle, with only about 10% utilization. Moreover, in stationary battery energy storage systems (BESS) designed for peak shaving, resting periods tend to cause more aging effects than the operational cycles. Consequently, quantifying the effect of calendar aging is crucial. However, current calendar aging models are inadequate for accurately modeling and predicting the diverse aging behaviors of commercial Li-ion batteries. In this study, we analyze a new, long-term Li-ion battery calendar aging dataset, which includes eight different commercial battery types. We compare and validate three calendar aging models—semi-empirical, symbolic regression, and Long Short-Term Memory Network (LSTM). We examine the transferability of these models across various commercial cell types, offering insights into their generalizability. Additionally, we introduce a novel trajectory-to-trajectory approach for early prediction of calendar aging lifetime. For the first time, we investigate the model's ability to interpolate and extrapolate aging behavior under different storage temperatures. This research provides practical insights for optimizing battery management strategies in conditions dominated by calendar aging.

Development of Organic Positive Electrodes for Rechargeable Aqueous Zinc-Ion Batteries for Stationary Energy Storage Systems

The rising concern towards the amount of anthropogenic carbon emissions and their effects on the environment has motivated the transition away from fossil fuels. The implementation of renewable energy sources has promoted the decarbonization of the power sector, but the variability of wind and solar energy necessitates the parallel deployment of high-performance energy storage infrastructure to ensure a reliable on-demand supply of green electricity to the grid. To this end, aqueous rechargeable zinc-ion batteries (ZIBs) are a promising new option for stationary energy storage owing to their high safety and low cost, when compared to established storage technologies like lithium-ion batteries. However, ZIBs are still limited by several technological challenges that hinder their uptake for commercial energy storage installations. In particular, the positive electrode materials, mostly comprised of metal oxides, are restraining the energy density and stability of the batteries and are yet under investigation. Low cost, long cycle life, and natural abundance are required properties of materials used in batteries for stationary energy storage. The search for materials with these properties has motivated the investigation of alternatives to metal oxides. One group of materials attracting considerable research attention is organic compounds which offer advantages like their natural abundance and high theoretical capacities. In this work, we developed an organic positive electrode for ZIBs using carbonyl groups as redox-active centers to provide energy storage capacity at round-trip energy efficiencies that are higher than the conventionally utilized manganese oxide electrodes. Furthermore, we investigated the effects of the conductive carbon additive on the deliverable capacity of the battery and elucidated the charge storage mechanism of this positive electrode material through detailed characterization. The results indicated that both Zn2+ and H+ are involved in the energy storage process of this organic electrode material. In addition to studying the energy storage process, degradation mechanisms were identified through nuclear magnetic resonance (NMR) and mass spectroscopy (MS). Both dissolution of the reduced form of the active material from the electrode and the formation of unwanted decomposition products are important contributors to the capacity fade of the battery. The technological and scientific insights provided in this presentation will thereby contribute towards the development of high-performance and naturally abundant electrode materials for the next generation of ZIBs to enable clean energy grid storage.

RETRACTED: Enhancing urban energy storage and optimization through advanced EV charging and vehicle-to-grid integration in a renewable-based zero-energy city

The variable natures of renewable power sources and the additional demand from EV (electric vehicle)-charging present unique challenges to electrical grids. This paper explores the potential for optimized energy synchronization at an urban scale in a city striving for net-zero energy status, utilizing wind and solar sources. It examines three scenarios for EV charging: smart, opportunistic, and V2G (vehicle-to-grid), with a specific city as the case study. The research aims to decline the discrepancy among energy supply and demand through intelligent charging and V2G strategies, formulated within the framework of quadratic programming. The analysis indicates that V2G integration, in conjunction with a balanced mix of wind and solar power, significantly enhances load matching in a zero-energy urban context. The transition from basic opportunistic charging to smart mode and then to V2G progressively improves the energy alignment. Within the ideal NZES (net-zero energy system), load matching-efficiency enhances from 67.6 % with opportunistic plan to 72.5 % with smart ones, and significantly to 83.4 % with V2G integration. Further, the full utilization of EV flexibility, particularly through an integrating a battery for EV (2400 MWh) in V2G framework as an alternating ESS (energy storage system), was equivalent to having a 1412 MWh stationary ESS in improving load-matching at an urban scale. The study also highlights the comparative effectiveness of EV batteries in a V2G configuration versus stationary ESSs in optimizing urban-scale energy-matching. These insights demonstrate the substantial potential of EVs to introduce flexibility and resilience into urban energy systems, facilitating the transition to sustainable urban living.

Air-Stable Na3.5C6O6 as a Sodium Compensation Additive in Cathode of Na-Ion Batteries.

Sodium-ion battery (SIB) is a candidate for the stationary energy storage systems because of the low cost and high abundance of sodium. However, the energy density and lifespan of SIBs suffer severely from the irreversible consumption of the Na-ions for the formation of the solid electrolyte interphase (SEI) layer and other side reactions on the electrodes. Here, Na3.5C6O6 is proposed as an air-stable high-efficiency sacrificial additive in the cathode to compensate for the lost sodium. It is characteristic of low desodiation (oxidation) potential (3.4-3.6V vs. Na+/Na) and high irreversible desodiation capacity (theoretically 378 mAh g-1). The feasibility of using Na3.5C6O6 as a sodium compensation additive is verified with the improved electrochemical performances of a Na2/3Ni1/3Mn1/3Ti1/3O2ǀǀhard carbon cells and cells using other cathode materials. In addition, the structure of Na3.5C6O6 and its desodiation path are also clarified on the basis of comprehensive physical characterizations and the density functional theory (DFT) calculations. This additive decomposes completely to supply abundant Na ions during the initial charge without leaving any electrochemically inert species in the cathode. Its decomposition product C6O6 enters the carbonate electrolyte without bringing any detectable negative effects. These findings open a new avenue for elevating the energy density and/or prolonging the lifetime of the high-energy-density secondary batteries.

Modelling a DC Electric Railway System and Determining the Optimal Location of Wayside Energy Storage Systems for Enhancing Energy Efficiency and Energy Management

Global demand for fossil fuels is highly increasing, necessitating energy efficiency to be enhanced in transitioning to low-carbon energy systems. Electric railways are highly efficient in reducing the transportation demand for fossil fuels as they are lightweight and their energy demand can be fed by renewable energy resources. Further, the regenerative braking energy of decelerating trains can be fed to accelerating trains and stored in onboard energy storage systems (ESSs) and stationary ESSs. It is fundamental to model electric railways accurately before investigating approaches to enhancing their energy efficiency. However, electric railways are challenging to model as they are nonlinear, resulting from the rectifier substations, overvoltage protection circuits, and the unpredictability and uncertainty of the load according to the train position. There have been few studies that have examined the ESS location’s impact on improving the energy efficiency of electric railways while using specialised simulation tools in electric railways. However, no single study exists that has studied the location impact of stationary ESSs on the energy efficiency of electric railways while the trains are supported by onboard ESSs. Given these goals and challenges, the main objective of this work is to develop a model using commercial software used by industry practitioners. Further, the energy saving is aimed to be maximised using stationary ESSs installed in optimal locations while trains are supported by onboard ESSs. The model includes trains, onboard ESSs, rail tracks, passenger stations, stationary ESSs, and traction power systems involving power lines, connectors, switches, sectioning, and isolators. In this article, a test scenario is presented comprising two trains running on a 20 km with three passenger stations and two substations. The trains and track are modelled in OpenTrack simulation software (Version 1.9) while the power system is modelled in OpenPowerNet simulation software (Version 1.11). The two simulation tools are used in the railway industry and can produce realistic results by taking into account the entire electrical network structure. A stationary ESS is added on the wayside and moved in steps of 1 km to obtain the optimal location before investigating the impact of stationary ESSs on the performance and energy management of onboard ESSs. It is found that the energy saving when installing a stationary ESS at the optimal location is 56.05%, the peak-power reduction of Substation 1 is 4.37%, and the peak-power reduction of Substation 2 is 18.67%.

Na-deficient P2-type layered oxide cathodes for practical sodium-ion batteries

Sodium-ion batteries (SIBs) have attracted enormous attention as candidates in stationary energy storage systems, because of the decent electrochemical performance based on cheap and abundant Na-ion intercalation chemistry. Layered oxides, the workhorses of modern lithium-ion batteries, have regained interest for replicating their success in enabling SIBs. A unique feature of sodium layered oxides is their ability to crystallize into a thermodynamically stable P2-type layered structure with under-stoichiometric Na content. This structure provides highly open trigonal prismatic environments for Na ions, permitting high Na+ mobility and excellent structural stability. This review delves into the intrinsic characteristics and key challenges faced by P2-type cathodes and then comprehensively summarizes the up-to-date advances in modification strategies from compositional design, elemental doping, phase mixing, morphological control, and surface modification to sodium compensation. The updated understanding presented in this review is anticipated to guide and expedite the development of P2-type layered oxide cathodes for practical SIB applications.

The Optimal Doping Ratio of Fe2O3 for Enhancing the Electrochemical Stability of Zeolitic Imidazolate Framework-8 for Energy Storage Devices

This paper aims to discover a novel composite material that has great potential for manufacturing high-performance supercapacitors suitable for diverse applications, such as electric vehicles, portable electronics, and stationary energy storage systems. Zeolitic imidazolate framework-8 (ZIF-8) doped by different concentrations up to 5 wt.% of nanosized Fe2O3 have been prepared (ZIF-8/Fe2O3). The effect of doping ratio 1, 3, and 5 wt.% on the structural and electrochemical properties of ZIF-8/Fe2O3 has been investigated. The structural characterization has been carried out using TGA, BET, XRD, and FTIR. The XRD analysis revealed that the crystalline size of our sample increased by approximately 16% as a result of doping ZIF-8 with 5 wt.% of Fe2O3. The structural analysis of the doped samples revealed that the material exhibited enhanced thermal stability and porosity, with an increase of approximately 105 m2/g. The introduction of doped nanometal oxides improved the capacitance value of ZIF-8 by significantly increasing its surface area. Additionally, the electron transport efficiency within ZIF-8/5 wt.% Fe2O3/electrode is increased. The Nyquist plot decreases as the doping of Fe2O3 increases. This indicates a decrease in the charge transfer resistance at the electrode–electrolyte interface, which is desired in applications such as batteries, fuel cells, or electrochemical sensors where faster electron transfer is needed for improved performance.

Joint planning for PV-SESS-MESS in distribution network towards 100% self-consumption of PV via consensus-based ADMM

The integration of distributed photovoltaic (PV) has become a prominent characteristic of distribution network (DN). However, achieving 100% PV self-consumption poses challenges due to intermittent generation and varying load demands. To address these challenges, this paper proposes an innovative joint planning method for PV, stationary energy storage system (SESS), and mobile energy storage system (MESS) using the consensus-based alternating directional multiplier method (ADMM). First, to account for multiple scenarios with real-world variations, a two-stage clustering method with clustering by fast search and finding of density peaks and k-means is employed. Second, a joint planning model for PV, SESS, and MESS is developed to minimize the total cost of DN, including installation, operation, and maintenance costs. The model optimizes the PV capacity, SESS capacity, and MESS capacity, as well as their locations. Third, a distributed planning framework is proposed using consensus-based ADMM, which decomposes the problem into a PV planning subproblem under the worst-case scenario and energy storage system planning subproblems under multiple scenarios. Finally, the proposed method is demonstrated on an IEEE-33 node system, and the results show the method effectively enhances the access capacity of PV by 11.80% and leads to a reduction in the total cost.

Feasibility Study of a Novel Secondary Zinc‐Flow Battery as Stationary Energy Storage System: From Design to Environmental Assessment

Herein, a zinc‐air flow battery (ZAFB) as an environmentally friendly and inexpensive energy storage system is investigated. For this purpose, an optimized ZAFB for households is designed based on the most recent publications, and an economic and ecological analysis of the system is carried out. The results show that the customer price of the designed ZAFB is estimated at ≈5000 € and is thus about one‐third lower than the quoted price for a comparable vanadium flow battery (VFB). The carbon footprint (CF) analysis shows that especially the alkaline electrolyte and the silver‐containing gas diffusion electrode have a high share of the greenhouse gas emissions of the ZAFB system. However, the CF is 41% lower than that of the VFB, highlighting the great potential of the ZAFB as an alternative home storage system.

Recovery of lithium by pseudocapacitive electrodes in capacitive deionization

Lithium is a crucial component in rechargeable lithium-ion batteries for many applications, including the powering of electric vehicles and stationary energy storage systems. This investigation focused on two hybrid pseudocapacitive materials, the polystyrene sulfonate-MXene composite (PM) and the sodium titanate/graphene oxide composite (NG), for lithium ions recovery from aqueous Li+ resources. This was achieved by selectively removing unwanted divalent Ca2+ and Mg2+ ions, as well as monovalent K+ ions, through capacitive deionization (CDI) using a single-cell system, resulting in a final solution enriched with Li+ ions. Based on the ion selectivity order observed previously as Mg2+≈ Ca2+ >K+ > Li+, a series of CDI experiments were conducted with sequential steps to remove more selective ions first and to obtain a lithium-enriched solution with higher purity and maximum extracted fraction. Both PM and NG electrodes demonstrated promising performance when tested in binary, ternary, and quaternary ionic solutions with the recovered lithium solution purity in the range of 59.09 %-95.94 % and 59.75 %-77.17 %, respectively. Further, the highest enrichment factor values observed were SLi+,Mg2+; 268.1 for PM and SLi+,Ca2+; 44.25, for NG electrodes. The PSS-modified MXene composite electrode in obtaining the Li+ solution with the highest purity when separated Ca2+ from a binary solution. These findings offer valuable insights into the selective electrosorption of divalent ions over lithium ions through the utilization of ion intercalation pseudocapacitive nanocomposite electrodes. The obtained results hold significance in advancing novel non-precipitation techniques for the recovery of lithium ions from aqueous lithium resources.

Quasi-Solid Sulfur Conversion for Energetic All-Solid-State Na-S Battery.

The high theoretical energy density (1274 Wh kg-1) and high safety enable the all-solid-state Na-S batteries with great promise for stationary energy storage system. However, the uncontrollable solid-liquid-solid multiphase conversion and its associated sluggish polysulfides redox kinetics pose a great challenge in tunning the sulfur speciation pathway for practical Na-S electrochemistry. Herein, we propose a new design methodology for matrix featuring separated bi-catalytic sites that control the multi-step polysulfide transformation in tandem and direct quasi-solid reversible sulfur conversion during battery cycling. It is revealed that the N, P heteroatom hotspots are more favorable for catalyzing the long-chain polysulfides reduction, while PtNi nanocrystals manipulate the direct and full Na2S4 to Na2S low-kinetic conversion during discharging. The electrodeposited Na2S on strongly coupled PtNi and N, P-codoped carbon host is extremely electroreactive and can be readily recovered back to S8 without passivation of active species during battery recharging, which delivers a true tandem electrocatalytic quasi-solid sulfur conversion mechanism. Accordingly, stable cycling of the all-solid-state soft-package Na-S pouch cells with an attractive specific capacity of 876 mAh gS -1 and a high energy of 608 Wh kgcathode -1 (172 Wh kg-1, based on the total mass of cathode and anode) at 60 °C are demonstrated.

Cooperative Application of Onboard Energy Storage and Stationary Energy Storage in Rail Transit Based on Genetic Algorithm

The transition towards environmentally friendly transportation solutions has prompted a focused exploration of energy-saving technologies within railway transit systems. Energy Storage Systems (ESS) in railway transit for Regenerative Braking Energy (RBE) recovery has gained prominence in pursuing sustainable transportation solutions. To achieve the dual-objective optimization of energy saving and investment, this paper proposes the collaborative operation of Onboard Energy-Storage Systems (OESS) and Stationary Energy-Storage Systems (SESS). In the meantime, Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is applied to optimize the ESS capacity and reduce its redundancy. The simulation is programmed in MATLAB. The results show that the corporation of OESS and SESS offers superior benefits (70 kWh energy saving within 30 min operation) compared to using SESS alone. Moreover, the OESS plays a significant role, emphasizing its significance in saving energy and investment, therefore presenting a win–win scenario. It is recommended that the capacity of OESS be designed to be two to three times that of SESS. The findings contribute to the ongoing efforts in developing more sustainable and energy-efficient transportation solutions, with implications for the railway industry’s investment and broader initiatives in energy saving for sustainable urban mobility.

Quasi‐Solid Sulfur Conversion for Energetic All‐Solid‐State Na−S Battery

AbstractThe high theoretical energy density (1274 Wh kg−1) and high safety enable the all‐solid‐state Na−S batteries with great promise for stationary energy storage system. However, the uncontrollable solid–liquid‐solid multiphase conversion and its associated sluggish polysulfides redox kinetics pose a great challenge in tunning the sulfur speciation pathway for practical Na−S electrochemistry. Herein, we propose a new design methodology for matrix featuring separated bi‐catalytic sites that control the multi‐step polysulfide transformation in tandem and direct quasi‐solid reversible sulfur conversion during battery cycling. It is revealed that the N, P heteroatom hotspots are more favorable for catalyzing the long‐chain polysulfides reduction, while PtNi nanocrystals manipulate the direct and full Na2S4 to Na2S low‐kinetic conversion during discharging. The electrodeposited Na2S on strongly coupled PtNi and N, P‐codoped carbon host is extremely electroreactive and can be readily recovered back to S8 without passivation of active species during battery recharging, which delivers a true tandem electrocatalytic quasi‐solid sulfur conversion mechanism. Accordingly, stable cycling of the all‐solid‐state soft‐package Na−S pouch cells with an attractive specific capacity of 876 mAh gS−1 and a high energy of 608 Wh kgcathode−1 (172 Wh kg−1, based on the total mass of cathode and anode) at 60 °C are demonstrated.

Business Models and Ecosystems in the Circular Economy Using the Example of Battery Second Use Storage Systems

The battery electric drive is an important component of sustainable mobility. However, this is associated with energy-intensive battery production and high demand for raw materials. The circular economy can be used to overcome these barriers. In particular, the secondary use of batteries in stationary energy storage systems (B2U storage systems) has been proposed for the circularity of electromobility. To implement such systems, a circular business model and a cross-industry ecosystem are required. However, the meaning, scope, and structure of these concepts have received little research to date. To close this gap, a theoretical construct for a circular business model based on the theory of business model, sustainability, circular economy, and ecosystem must be developed. On this basis, 16 expert interviews were conducted and analyzed using qualitative content analysis. Numerous challenges resulted from the analysis. The willingness to pay for B2U storage systems is limited, the availability of second-life batteries is restricted, and dismantling as well as testing the batteries is time-consuming. Product-service systems help to increase the willingness to pay and expand the value proposition and value capture, digital technologies realize cost-efficient value creation, and an effective ecosystem enables the expansion of battery procurement.

Battery capacity estimation based on a co-learning framework with few-labeled and noisy data

Battery capacity estimation plays a crucial role in optimizing the performance and longevity of electric vehicles and stationary energy storage systems. However, accurately estimating battery capacity becomes challenging in real-world applications, particularly when dealing with unlabeled and noisy capacity data. To address this issue, this paper presents a co-learning framework incorporating both supervised and self-supervised learning for estimating battery capacity in the presence of few-labeled and noisy data. By training a shared encoder network with both self-supervised and supervised heads, the framework maximizes the agreement between the two heads in the latent space. The proposed approach demonstrates improved accuracy in battery capacity estimation in those challenging scenarios based on two public datasets. Comparative experiments show that the co-learning approach outperforms conventional end-to-end mapping methods, the average root mean square error of the proposed method is reduced at least by 36% and 19% under insufficient and noisy label conditions, respectively, leading to significant enhancements in estimation performance.

Engineering Dry Electrode Manufacturing for Sustainable Lithium-Ion Batteries

The pursuit of industrializing lithium-ion batteries (LIBs) with exceptional energy density and top-tier safety features presents a substantial growth opportunity. The demand for energy storage is steadily rising, driven primarily by the growth in electric vehicles and the need for stationary energy storage systems. However, the manufacturing process of LIBs, which is crucial for these applications, still faces significant challenges in terms of both financial and environmental impacts. Our review paper comprehensively examines the dry battery electrode technology used in LIBs, which implies the use of no solvents to produce dry electrodes or coatings. In contrast, the conventional wet electrode technique includes processes for solvent recovery/drying and the mixing of solvents like N-methyl pyrrolidine (NMP). Methods that use dry films bypass the need for solvent blending and solvent evaporation processes. The advantages of dry processes include a shorter production time, reduced energy consumption, and lower equipment investment. This is because no solvent mixing or drying is required, making the production process much faster and, thus, decreasing the price. This review explores three solvent-free dry film techniques, such as extrusion, binder fibrillation, and dry spraying deposition, applied to LIB electrode coatings. Emphasizing cost-effective large-scale production, the critical methods identified are hot melting, extrusion, and binder fibrillation. This review provides a comprehensive examination of the solvent-free dry-film-making methods, detailing the underlying principles, procedures, and relevant parameters.