Batteries, Volume 8, Issue 11 (November 2022) – 54 articles

Lithium-ion batteries (LIBs) are widely used in electric vehicles (EV) and energy storage stations (ESS). However, combustion and explosion accidents during the thermal runaway (TR) process limit its further applications. Therefore, it is necessary to investigate the uncontrolled TR exothermic reaction for safe battery system design. In this study, different LIBs are tested by lateral heating in a closed experimental chamber filled with nitrogen. Moreover, the relevant thermal characteristic parameters, gas composition, and deflagration limit during the battery TR process are calculated and compared. Results indicate that the TR behavior of NCM batteries is more severe than that of LFP batteries, and the TR reactions becomes more severe with the increase of energy density. Under the inert atmosphere of nitrogen, the primarily generated gases are H₂, CO, CO₂, and hydrocarbons. The TR gas deflagration limits and characteristic parameter calculations of different cathode materials are refined and summarized, guiding safe battery design and battery selection for power systems. Full article

Limited by the service life, a large amount of spent lithium-ion batteries (LIBs) have been produced in recent years. Without proper disposal, spent LIBs can cause environmental pollution and waste of resources. In this paper, we focus on the recycling of the graphite anode (GA) in spent LIBs. GAs from spent LIBs were converted to graphene oxide (GO) through a modified Hummers method. Then the prepared GO was applied to absorb methylene blue in dyeing wastewater under different reaction conditions. The experimental results indicate that GO can quickly and effectively adsorb methylene blue, which also exhibits thermal stability. The maximum adsorption capacity and removal rate are about 833.11 mg/g and 99.95%, respectively. The adsorption kinetics and isotherms were investigated; the adsorption process of GO is more consistent with the pseudo-second-order adsorption kinetic model while the isotherm is close to the Langmuir isotherm. This study is of great significance for the economy and environment. The reaction can turn waste into wealth and is a win-win approach for both spent LIBs recycling and dyeing wastewater cleaning. Full article

The frequent safety accidents involving lithium-ion batteries (LIBs) have aroused widespread concern around the world. The safety standards of LIBs are of great significance in promoting usage safety, but they need to be constantly upgraded with the advancements in battery technology and the extension of the application scenarios. This study comprehensively reviews the global safety standards and regulations of LIBs, including the status, characteristics, and application scope of each standard. A standardized test for thermal runaway triggering is also introduced. The recent fire accidents in electric vehicles and energy storage power stations are discussed in relation to the upgrading of the rational test standards. Finally, the following four suggestions for improving battery safety are proposed to optimize the safety standards: (1) early warning and cloud alarms for the battery’s thermal runaway; (2) an innovative structural design for a no-fire battery pack; (3) the design of a fire water injection interface for the battery pack; (4) the design of an immersive energy storage power station. This study provides insights for promoting the effectiveness of relevant safety standards for LIBs, thereby reducing the failure hazards. Full article

Silicon carbide has structural strength, high electronic conductivity, low diffusion barrier and high storage capacity, which are suitable for engineering applications such as lithium-ion batteries, electric vehicles, uninterruptible power supplies and SiC diodes. In particular, 3C-SiC monolayers oriented along the (1 1 0) crystallographic direction that could have symmetric surfaces have been poorly studied, as have the effects of surface passivation on their physical and electronic properties. In this work, we investigate the influence of lithium on the electronic properties of hydrogenated surfaces in 3C-SiC monolayers using density functional theory. We examine the electronic properties of surfaces fully passivated with hydrogen with those of surfaces fully passivated with lithium and those with mixed passivation. Our results show that only fully hydrogenated surfaces exhibit a direct band-gap, while the full Li, CH+SiLi, and H+Li${}_c$ passivations exhibit metallic behavior. The CLi+SiH, H+1LiC, and H+1LiSi passivation systems decrease the band-gap compared to the hydrogenated case and show an indirect band-gap. The formation energy of the system shows that the most stable arrangement is full-H, followed by H+1LiC, and the most unstable system is full-Li, which has a positive formation energy. Full article

Lithium secondary batteries have been the most successful energy storage devices for nearly 30 years. Until now, graphite was the most mainstream anode material for lithium secondary batteries. However, the lithium storage mechanism of the graphite anode limits the further improvement of the specific capacity. The lithium metal anode, with the lowest electrochemical potential and extremely high specific capacity, is considered to be the optimal anode material for next-generation lithium batteries. However, the lifetime degradation and safety problems caused by dendrite growth have seriously hindered its commercialization. Carbon materials have good electrical conductivity and modifiability, and various carbon materials were designed and prepared for use in lithium metal batteries. Here, we will start by analyzing the problems and challenges faced by lithium metal. Then, the application progress and achievements of various carbon materials in lithium metal batteries are summarized. Finally, the research suggestions are given, and the application feasibility of carbon materials in metal lithium batteries is discussed. Full article

Antimony (Sb) is regarded to be a potential alloying-type anode for lithium-ion batteries due to its excellent electrochemical reversibility and high theoretical specific capacity (660 mA h g⁻¹). However, huge volume expansion accompanying rapid capacity fading seriously hinders its commercial application. Herein, double-carbon-modified spindle-structured Sb@C@NC were constructed via galvanic replacement using a Fe-based metal-organic framework (MOF) with polydopamine-coated-derived Fe@C@NC as reactants. Due to the unique double-carbon-encapsulated structure, the Sb@C@NC anode effectively moderates the volume fluctuation and maintains the integral framework from collapsing during the annealing and cycling process. As lithium-ion battery (LIB) anodes, Sb@C@NC attained excellent cycling performance (389 mAh g⁻¹ at 100 mA g⁻¹ after 100 cycles) and superior rate capability (a reversible capacity of 343 mAh g⁻¹ at 2000 mA g⁻¹). Such an MOF-based approach provides an adjustable strategy for Sb-based nanomaterial and shield light on the applications of Sb@C@NC in other fields. Full article

Metal–air batteries hold a competitive energy density and are frequently recommended as a solution for low-cost, environmentally friendly electrochemical energy storage applications. Rechargeable zinc–air batteries are prominently studied future devices for energy storage applications. Up to date and despite substantial efforts over the last decades, it is not commercialized on a broader scale because of inadequate performance. Most essential, the ultimate long-term functional zinc–air battery has yet to be discovered. This challenge should be resolved appropriately before articulating the zinc–air batteries to commercial reality and be deployed widespread. We review the present status and some breakthroughs in rechargeable zinc–air batteries research in the last few years, focusing on the anode-related issues. A critical overview of the last five years of the still less explored but essential aspects of rechargeability in zinc–air batteries, such as zinc utilization, solid electrolyte interface, and cell design is presented, some perspectives on possible solutions are offered. Full article

This study aimed to achieve a clear understanding of the response characteristics of soft pack battery extrusion conditions under various situations. In this study, we chose a LiCoO₂ battery as the research object of the extrusion experiment. First, the repeatability of the extrusion test on the battery was verified. A quasi-static extrusion test was conducted on three groups of batteries in the same state, and the load-displacement curves of the three groups of experimental batteries were almost the same. Then, the influence of the extrusion speed on the battery thermal runaway was studied. The results show that a different extrusion speed has a certain impact on the thermal runaway performance of the battery. The peak load of the battery is lower at a lower speed. Finally, the study found that every 20% change in SOC has a greater impact on the battery response under a squeeze. The larger the SOC, the more severe the battery thermal runaway. Through an analysis of multiple experimental cases, it is possible to have a deeper understanding of the temperature and voltage characteristics of lithium batteries when a thermal runaway occurs, which provides ideas for monitoring the trend of the thermal runaway of electric vehicles. Full article

Potassium-based batteries represent one of the emerging classes of post-lithium electrochemical energy storage systems in the international scene, due to both the abundance of raw materials and achievable cell potentials not far from those of lithium batteries. In this context, it is important to define electrodes and electrolytes that give reproducible performance and that can be used by different research groups as an internal standard when developing new materials. We propose molybdenum disulfide (MoS₂) as a valid anode choice, being a commercial and easily processable material, the 2D layered structure of which is promising for large potassium ions reversible storage. It has been proven to work for hundreds of cycles, keeping a constant specific capacity around 100 mAh g⁻¹ while also preserving its electrochemical interphase and morphology. Full article

Developing electrodes in a reasonable structure is essential to boost the performance of supercapacitors. Self-supporting heterostructures enriched active sites are promising as binder-free electrodes for supercapacitors. Here, core-shell layered double hydroxide (LDH)/Metal organic frame (MOF) heterostructure was directly grown on carbon cloth (CC) substrate derived from L-Co ZIF NWAs. Subsequently, the composite was treated with a sulfidation process to optimize its electrical conductivity. Thanks to its unique network structure, it facilitates active site exposure and efficient charge transfer, together with the synergetic effect between NiCo double hydroxide and Ni MOF nanosheets. This hybrid electrode possesses an excellent specific capacity (1200 F g⁻¹ at 1 A g⁻¹) and stable cycle performance with 86% capacity maintained after 4000 cycles, indicating its potential superiority for use in high-efficiency electrochemical capacitors. Full article

This study proposes a novel bidirectional isolated DC/DC converter with a high gain ratio and wide input voltage for electric vehicle (EV) storage systems. The DC bus of an EV can be used to charge its battery, and the battery pack can discharge energy to the DC bus through the bidirectional converter when the DC bus lacks power. The input voltage range of the proposed converter is 24 to 58 V on the low-voltage side, which meets the voltage specifications of most servers and batteries on the market. The proposed topology is verified through design, simulation, and implementation, and voltage gain, voltage stress, and current stress are investigated. The control bidirectional converter is simple. Only one set of complementary signals is required for step-up and step-down modes, which greatly reduces costs. The converter also features a continuous current at the low-voltage side, a leakage inductance function for energy recovery, and zero-voltage switching (ZVS) on certain switches, which can prevent voltage spikes on the switches and increase the efficiency of the proposed converter. A bidirectional converter with a total power of 1 kW is used to verify the topology’s feasibility and practicability. The power at the low-voltage side was 24–58 V, and the maximum efficiency in step-up mode was 94.5%, 96.5%, and 94.8%, respectively; the maximum efficiency in step-down mode was 94.4%, 95.4%, and 93.7%, respectively. Full article

The intrinsic high safety of rechargeable aqueous batteries makes them particularly advantageous in the field of large-scale energy storage. Among them, rechargeable Zn–Mn batteries with high energy density, low cost, high discharge voltage, and nontoxicity have been considered as one of the most promising aqueous battery systems. However, exiting research on manganese-based cathode materials mainly focuses on diverse manganese oxides analogs, while reports on other promising manganese-based analogs with high performance are still limited. Herein, we report a MnCO₃ cathode material, which can be manufactured on a large scale by a facile coprecipitation method. Interestingly, the MnCO₃ can spontaneously be converted into MnO₂ material during the charging process. The Zn–MnCO₃ battery delivers a highly specific capacity (280 mAh g⁻¹) even at the high current density of 50 mA g⁻¹. It is also noteworthy that the battery with a high loading mass (7.2 mg cm⁻²) exhibits good reversibility of charge–discharge for 2000 cycles, showing a competitive cycling stability in aqueous systems. Full article

This paper introduces the use of a new low-computation cost algorithm combining neural networks with the Nelder–Mead simplex method to monitor the variations of the parameters of a previously selected equivalent circuit calculated from Electrochemical Impedance Spectroscopy (EIS) corresponding to a series of battery aging experiments. These variations could be correlated with variations in the battery state over time and, therefore, identify or predict battery degradation patterns or failure modes. The authors have benchmarked four different Electrical Equivalent Circuit (EEC) parameter identification algorithms: plain neural network mapping EIS raw data to EEC parameters, Particle Swarm Optimization, Zview, and the proposed new one. In order to improve the prediction accuracy of the neural network, a data augmentation method has been proposed to improve the neural network training error. The proposed parameter identification algorithms have been compared and validated through real data obtained from a six-month aging test experiment carried out with a set of six commercial 80 Ah VLRA batteries under different cycling and temperature operation conditions. Full article

The development of high-rate and long-cycle-life Na-based cathode materials, on par with the performance of commercialized lithium-based cathodes, is crucial to satisfy the recurring surge in energy demand. Here, we report an interconnected bead-like P2-type manganese-based oxide Na_xCo_yMn_1−yO₂ (x = 0.66, y = 0.1) synthesized by electrospinning and subsequent heat treatment as a high-rate cathode material for sodium-ion batteries (SIBs). The employed strategy of one-dimensional morphological design with interconnected bead-like particles profusely enhances Na⁺ diffusion pathways. This layered cathode material exhibits a stable and superior discharge capacity of 180.0 mAh g⁻¹ at 50 mA g⁻¹ compared to a bare cathode material synthesized via the sol–gel process. Further, a high capacity of 78.3 mAh g⁻¹ was achieved, maintaining excellent capacity retention of 85.0% even after 500 insertion/desertion cycles implying robust Na⁺ storage properties. High-rate tests also revealed promising electrochemical performances at C-rates as high as 5000 mA g⁻¹, affirming the potential of this layered cathode material for high-rate Na⁺ storage. Additionally, full SIBs assembled with a Na_xCo_yMn_1−yO₂ (x = 0.66, y = 0.1) cathode and a carbon nanofiber (CNF) anode exhibited a high cycle performance, retaining 96.3 mAh g⁻¹ after 100 cycles at 300 mA g⁻¹. Full article

Thermal management systems are integral to electric and hybrid vehicle battery packs for maximising safety and performance since high and irregular battery temperatures can be detrimental to these criteria. Lithium-ion batteries are the most commonly used in the electric vehicle (EV) industry because of their high energy and power density and long life cycle. Liquid cooling provides superior performance with low power draw and high heat transfer coefficient. Two liquid cooling designs-the Linear Channel Design (LCD) and Helical Channel Design (HCD)-underwent multiple numerical and geometrical optimisations, where inlet mass flow rate, channel diameter, and inlet and outlet locations were analysed using CFD (computational fluid dynamics). The primary objectives were to maintain maximum temperatures and thermal uniformity within the operational limits derived from the literature. These were both achieved with the LCD using a mass flow rate of 7.50E-05 kgs⁻¹. The T_max goal was met for the HCD but not the thermal uniformity goal. The LCD achieved 1.796 K lower in maximum temperature and 8.740 K lower in temperature difference compared to the HCD, proving itself superior in both metrics. The HCD required a higher mass flow rate than the LCD to regulate temperatures, resulting in an undesirably high power consumption. Full article

Deformations in lithium-ion batteries, which may lead to thermal runaway, can occur during storage and transportation handling, as well as in road use. In this study, both radial and axial compression deformation were produced experimentally to analyze their influence on the performance and safety of lithium-ion batteries. In the radial plate compression experiment, the battery was loaded to different displacements and then charge–discharge cycles were performed. It was found that the greater the deformation of the battery, the smaller the initial capacity and the faster the capacity decay. Under axial loading, the voltage of low state of charge (SOCs) batteries showed a clear step-drop phenomenon. The battery was compressed until the first voltage drop, loading was stopped, and the voltage gradually dropped to 0 V. For high-SOC lithium-ion batteries, there was almost no voltage step-down, and a small deformation could cause thermal runaway in the battery. The results showed that the small deformation in the radial direction only reduced the capacity of the battery, but had little impact on its safety, whereas a small deformation in the axial direction was more likely to cause an internal short circuit (ISC). Full article

Electric vehicles (EVs) in severe cold regions face the real demand for fast charging under low temperatures, but low-temperature environments with high C-rate fast charging can lead to severe lithium plating of the anode material, resulting in rapid degradation of the lithium-ion battery (LIB). In this paper, by constructing an electrode–thermal model coupling solid electrolyte interphase (SEI) growth and lithium plating, the competition among different factors of capacity degradation under various ambient temperatures and C-rates are systematically analyzed. In addition, the most important cause of rapid degradation of LIBs under low temperatures are investigated, which reveal the change pattern of lithium plating with temperature and C-rate. The threshold value and kinetic law of lithium plating are determined, and a method of lithium-free control under high C-rate is proposed. Finally, by studying the average aging rate of LIBs, the reasons for the abnormal attenuation of cycle life at lower C-rates are ascertained. Through the chromaticity diagram of the expected life of LIBs under various conditions, the optimal fast strategy is explored, and its practical application in EVs is also discussed. This study can provide a useful reference for the development of high-performance and high-safety battery management systems to achieve fine management. Full article

In this work, a fiber Bragg grating (FBG) sensor network inscribed in a polarization-maintaining (PM) fiber is proposed to proceed with a multipoint simultaneous temperature and strain discrimination in different locations (positive and negative terminals, and middle) on a cylindrical Li-ion battery. The birefringence property of the PM fibers, together with FBG sensors, allowed such an application using only one fiber line fixed to the edges of the battery. The battery was subjected to two different charge/discharge cycles, one with nominal charging and discharging conditions (1.00 C and 1.13 C, respectively) and another with abusive conditions (1.88 C for charge and 2.39 C for discharge). The PM-FBG sensors registered maximum temperature and strain variations at the end of the abusive discharge process of the battery; the positive terminal achieved a 28.7 ± 0.3 °C temperature variation, while the center achieved 221 ± 10 με strain variation. The results indicate a different strain variation behavior in the middle location when compared to the negative and positive terminals, as well as a higher temperature variation in both terminals when compared to the middle location. The use of PM-FBG sensors successfully demonstrates their feasibility in locally tracking and discriminating strain and temperature shifts in a battery surface. To our knowledge, this is the first study using the application of PM-FBG sensors to monitor and discriminate critical safety parameters in Li-ion batteries. Full article

Taking advantage of electrode thicknesses well beyond conventional dimensions allowed us to follow the surface plasmonic THz frequency phenomenon with vacuum wavelengths of 100 μm to 1 mm, only to scrutinize them within millimeters-thicknesses insulators. Here, we analyze an Al/insulator/Cu cell in which the metal electrodes-collectors were separated by a gap that was alternatively filled by SiO₂, MgO, Li₂O, Na₃Zr₂Si₂PO₁₂–NASICON, Li_1.5Al_0.5Ge_1.5(PO₄)₃–LAGP, and Li_2.99Ba_0.005ClO–Li⁺ glass. A comparison was drawn using experimental surface chemical potentials, cyclic voltammetry (I-V plots), impedance spectroscopy, and theoretical approaches such as structure optimization, simulation of the electronic band structures, and work functions. The analysis reveals an unexpected common emergency from the cell’s materials to align their surface chemical potential, even in operando when set to discharge under an external resistor of 1842 Ω.cm_insulator. A very high capability of the metal electrodes to vary their surface chemical potentials and specific behavior among dielectric oxides and solid electrolytes was identified. Whereas LAGP and Li₂O behaved as p-type semiconductors below 40 °C at OCV and while set to discharge with a resistor in agreement with the Li⁺ diffusion direction, NASICON behaved as a quasi n-type semiconductor at OCV, as MgO, and as a quasi p-type semiconductor while set to discharge. The capacity to behave as a p-type semiconductor may be related to the ionic conductivity of the mobile ion. The ferroelectric behavior of Li_2.99Ba_0.005ClO has shown surface plasmon polariton (SPP) waves in the form of surface propagating solitons, as in complex phenomena, as well as electrodes’ surface chemical potentials inversion capabilities (i.e., χ (Al) − χ (Cu) > 0 to χ (Al) − χ (Cu) < 0 vs. E_vacuum = 0 eV) and self-charge (ΔV_cell ≥ +0.04 V under a 1842 Ω.cm_insulator resistor). The multivalent 5.5 mm thick layer cell filled with Li_2.99Ba_0.005ClO was the only one to display a potential bulk difference of 1.1 V. The lessons learned in this work may pave the way to understanding and designing more efficient energy harvesting and storage devices. Full article

Laser-induced breakdown spectroscopy (LIBS) is a valuable tool for the solid-state elemental analysis of battery materials. Key advantages include a high sensitivity for light elements (lithium included), complex emission patterns unique to individual elements through the full periodic table, and record speed analysis reaching 1300 full spectra per second (1.3 kHz acquisition rate). This study investigates deep learning methods as an alternative tool to accurately recognize different compositions of similar battery materials regardless of their physical properties or manufacturer. Such applications are of interest for the real-time digitalization of battery components and identification in automated manufacturing and recycling plant designs. Full article

Energy storage systems have aroused public interest because of the blooming development of intermittent renewable energy sources. Vanadium redox flow batteries (VRFBs) are the typical candidates owing to their flexible operation and good cycle durability. However, due to the usage of perfluorinated separator membranes, VRFBs suffer from both high cost and serious vanadium ions cross penetration. Herein, we fabricate a series of low-budget and high-performance blend membranes from polyvinylpyrrolidone (PVP) and cardo-poly(etherketone) (PEKC) for VFRB. A PEKC network gives the membrane excellent mechanical rigidity, while PVP endows the blend membranes with superior sulfonic acid uptake owing to the present N-heterocycle and carbonyl group in PVP, resulting in low area resistance. Meanwhile, blend membranes also display low vanadium ion permeability resulting from the electrostatic repulsion effect of protonated PVP polymer chains towards vanadium ions. Consequently, the 50%PVP-PEKC membrane has a high ionic selectivity of 1.03 × 10⁶ S min cm⁻³, while that of Nafion 115 is nearly 17 times lower (6.03 × 10⁴ S min cm⁻³). The VRFB equipped with 50%PVP-PEKC membrane has high coulombic efficiencies (99.3–99.7%), voltage efficiencies (84.6–67.0%) and energy efficiencies (83.9–66.8%) at current densities of 80–180 mA cm⁻², and possesses excellent cycle constancy, indicating that low-cost x%PVP-PEKC blend membranes have a great application potentiality for VRFBs. Full article

With the widespread use of Lithium-ion (Li-ion) batteries in Electric Vehicles (EVs), Hybrid EVs and Renewable Energy Systems (RESs), much attention has been given to Battery Management System (BMSs). By monitoring the terminal voltage, current and temperature, BMS can evaluate the status of the Li-ion batteries and manage the operation of cells in a battery pack, which is fundamental for the high efficiency operation of EVs and smart grids. Battery capacity estimation is one of the key functions in the BMS, and battery capacity indicates the maximum storage capability of a battery which is essential for the battery State-of-Charge (SOC) estimation and lifespan management. This paper mainly focusses on a review of capacity estimation methods for BMS in EVs and RES and provides practical and feasible advice for capacity estimation with onboard BMSs. In this work, the mechanisms of Li-ion batteries capacity degradation are analyzed first, and then the recent processes for capacity estimation in BMSs are reviewed, including the direct measurement method, analysis-based method, SOC-based method and data-driven method. After a comprehensive review and comparison, the future prospective of onboard capacity estimation is also discussed. This paper aims to help design and choose a suitable capacity estimation method for BMS application, which can benefit the lifespan management of Li-ion batteries in EVs and RESs. Full article

The random nature of renewable sources causes power fluctuations affecting the stability in the utility grid. This problem has motivated the development of new power smoothing techniques using supercapacitors and batteries. However, experimental studies based on multiple renewable sources (photovoltaic, wind, hydrokinetic) that demonstrate the validity of power smoothing techniques under real conditions still require further study. For this reason, this article presents a feasibility study of a renewable grid-connected system, addressing various aspects based on power quality and energy management. The first of them is related to the fluctuations produced by the stochastic characteristics of renewable sources and demand. Two power smoothing algorithms are presented (ramp rate and moving average) combining photovoltaic, wind, and hydrokinetic sources with a hybrid storage system composed of supercapacitors and lithium-ion batteries. Then, the self-consumption for an industrial load is analyzed by studying the energy flows between the hybrid renewable energy sources and the grid. The main novelty of this paper is the operability of the supercapacitor. The experimental results show that when applying the power smoothing ramp rate method, the supercapacitor operates fewer cycles with respect to the moving average method. This result is maintained by varying the capacity of the renewable sources. Moreover, by increasing the capacity of photovoltaic and wind renewable sources, the hybrid storage system requires a greater capacity only of supercapacitors, while by increasing the capacity of hydrokinetic turbines, the battery requirement increases considerably. Finally, the cost of energy and self-consumption reach maximum values by increasing the capacity of the hydrokinetic turbines and batteries. Full article

During the discharge of Na–O₂ batteries, O₂ is reduced and combines with Na⁺ to form an insulating solid sodium oxide on the cathode, which severely hinders the mass transfer path, resulting in high polarization voltage, low energy efficiency, and short battery life. Hereby, we proposed a novel illumination-assisted Na–O₂ battery in which bismuth vanadate (BiVO₄) with few defects and high surface areas was used as the catalyst. It showed that the charge overpotential under photo assistance reduced by 1.11 V compared with that of the dark state one. Additionally, the insolating sodium oxide discharge products were completely decomposed, which was the key to running Na–O₂ batteries over 200 cycles with a charge potential of no more than 3.65 V, while its counterpart (under dark condition) at 200 cycles had the charge potential higher than 4.25 V. The experiment combined with theoretical calculation shows that few defects, high surface areas, the altered electron transfer kinetics, and the low energy gap and low oxygen absorption energy of the (040) crystal face of monoclinic BiVO₄ play an important role in catalyzing oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Full article

Li₇La₃Zr₂O₁₂ is considered to be a promising solid electrolyte for all-solid-state batteries. The problem of the poor wettability of Li₇La₃Zr₂O₁₂ by metallic Li can be solved by using Li-In alloys as anode materials. Li-In alloys with different Li contents (40–90 at%) were prepared by an in situ method and investigated in symmetric cells with a Li₇La₃Zr₂O₁₂-based solid electrolyte. The interface resistance between the Li-In alloy (90 at% Li) and solid electrolyte is equal to ~11 Ω cm² at 200 °C. The cells with 80–90 at% Li in the Li-In anode show stable behavior during cycling with an applied current of ±8 mA (40 mA cm⁻²). No degradation of the Li₇La₃Zr₂O₁₂-based solid electrolyte in contact with the lithium–indium alloy was observed after galvanostatic cycling. Therefore, the Li-In alloy obtained by our in situ method can be applied as an anode material with Li₇La₃Zr₂O₁₂-based solid electrolyte in lithium power sources. Full article

Efficient extraction of Li from brine at a low cost is becoming a key technology to solve energy and environmental problems. Electrochemical extraction of Li has become a research hotspot due to its low energy consumption, high selectivity, and environmental friendliness. LiMn₂O₄, LiFePO₄, and LiNi_1/3Co_1/3Mn_1/3O₂ are widely used as cathode materials for the electrochemical extraction of Li but they also have some drawbacks, such as a small adsorption capacity. In this paper, the principle of electrochemical Li extraction from brine is reviewed and the research progress and analysis of the above three working electrode materials is summarized. In addition, analysis of the extraction of other rare ions from the working electrode material and the effect of micro-organisms on the working electrode material is also presented. Next, the shortcomings of working electrode materials are expounded upon and the research direction of working electrode materials in electrochemical Li extraction technology are prospected. It is hoped that this paper can provide insights and guidance for the research and application of electrochemical Li extraction from brine. Full article

The safety issue of lithium-ion batteries is a great challenge for the applications of EVs. The internal short circuit (ISC) of lithium-ion batteries is regarded as one of the main reasons for the lithium-ion batteries failure. However, the online ISC diagnosis algorithm for real vehicle data remains highly imperfect at present. Based on the onboard data from the cloud battery management system (BMS), this work proposes an ISC diagnosis algorithm for battery packs with high accuracy and high robustness via voltage anomaly detection. The mean-difference model (MDM) is applied to characterize large battery packs. A diagram of the adaptive integrated prediction algorithm combining MDM and a bi-directional long short-term memory (Bi-LSTM) neural network is firstly proposed to approach the voltage prediction of each cell. The diagnosis of an ISC is realized based on the residual analysis between the predicted and the actual state. The experimental data in DST conditions evaluate the proposed algorithm by comparing it with the solo equivalent circuit-based prediction algorithm and the Bi-LSTM based prediction algorithm. Finally, through the practical vehicle data from the cloud BMS, the diagnosis and pre-warn ability of the proposed algorithm for an ISC and thermal runaway (TR) in batteries are verified. The ISC diagnosis algorithm that is proposed in this paper can effectively identify the gradual ISC process in advance of it. Full article

Porous materials as electrode materials have demonstrated numerous benefits for high-performance Zn-ion batteries in recent years. In brief, porous materials as positive electrodes provide distinctive features such as faster electron transport, shorter ion diffusion distance, and richer electroactive reaction sites, which improve the kinetics of positive electrode reactions and achieve higher rate capacity. On the other hand, the porous structures as negative electrodes also exhibit electrochemical properties possessing higher surface area and reducing local current density, which favors the uniform Zn deposition and restrains the dendrite formation. In view of their advantages, porous electrode materials for ZIB are expected to be extensively applied in electric and hybrid electric vehicles and portable electronic devices. In this review, we highlight the methods of synthesizing porous electrode materials and discuss the mechanism of action of porous structures as electrodes on their electrochemical properties. At the end of this review, the perspectives on the future development of porous materials in the field of electrochemical energy storage are also discussed. Full article

Parameter identification with the pseudo-two-dimensional (p2D) model has been an important research topic in battery engineering because some of the physicochemical parameters used in the model can be measured, while some can only be estimated or calculated based on the measurement data. Various methods, either in the time domain or frequency domain, have been proposed to identify the parameters of the p2D model. While the methods in each domain bring their advantages and disadvantages, a comprehensive comparison regarding parameter identifiability and accuracy is still missing. In this present work, some selected physicochemical parameters of the p2D model are identified in four different cases and with different methods, either only in the time domain or with a combined model. Which parameters are identified in the frequency domain is decided by a comprehensive analysis of the analytical expression for the DRT spectrum. Finally, the parameter identifiability results are analyzed and the validation results with two highly dynamic load profiles are shown and compared. The results indicate that the model with ohmic resistance and the combined method achieves the best performance and the average voltage error is at the level of 12 mV. Full article

Two different Zn-based batteries are tested, simultaneously recording the voltage of the negative and positive electrodes during the discharge/charge processes to evidence the advantages of using a three-electrode cell, including a pseudo-reference electrode, with respect to the normally applied two electrodes system. The three-electrode cell allows us to identify in each moment which electrode reveals unexpected events during a battery test and thus to act on it accordingly. In this work, alkaline Zn/Bi₂O₃ and Zn/air batteries, including a pseudo-reference electrode, are subjected to different galvanostatic discharge/charge tests, highlighting several unforeseen changes and failures in both negative and positive electrodes. Thus, the usefulness of using a three-electrodes system in Zn-based batteries is revealed because it allows us to explain what the cause of the battery failure was and, if necessary, to act immediately. Finally, Spectroscopic Impedance measurements are also applied to a specific case of the Zn/Bi₂O₃ battery using the same three-electrode cell. Full article