Rechargeable Lithium Batteries Research Articles

Al–Ta dual-substituted Li7La3Zr2O12 ceramic electrolytes with two-step sintering for Stable All-solid-state Lithium Batteries

Cubic phase Li7La3Zr2O12 (LLZO) is a promising electrolyte material for all-solid-state rechargeable lithium-ion batteries. The homogeneous densification of the garnet solid electrolyte ceramic material is crucial for enhancing its ionic conductivity performance. Herein, an Al/Ta co-doped strategy is employed to stabilize the cubic phase structure of LLZO and is combined with a two-step sintering method to enhance densification, in order to investigate its effect on microstructure, ionic conductivity, and electrochemical properties. During the formation process, amorphous Li2O reacts with doped Al2O3 to create a Li–Al–O liquid phase at the grain boundaries. Combined with two-step sintering to ensure that the desired material transformation is achieved, resulting in a dense microstructure and better mechanical properties. The solid electrolyte Li6.4Al0.1La3Zr1.7Ta0.3O12 under two-step sintering (LLZATO-2) is successfully synthesized, delivering an ionic conductivity up to 7.33 × 10−4 S cm−1 at room temperature and an activation energy of 0.22 eV. This work also highlights the critical role of co-doping combined with two-step sintering in preparing well-performing solid-state electrolytes and all-solid-state lithium-ion batteries.

Molecular-docking electrolytes enable high-voltage lithium battery chemistries.

Ideal rechargeable lithium battery electrolytes should promote the Faradaic reaction near the electrode surface while mitigating undesired side reactions. Yet, conventional electrolytes usually show sluggish kinetics and severe degradation due to their high desolvation energy and poor compatibility. Here we propose an electrolyte design strategy that overcomes the limitations associated with Li salt dissociation in non-coordinating solvents to enable fast, stable Li chemistries. The non-coordinating solvents are activated through favourable hydrogen bond interactions, specifically Fδ--Hδ+ or Hδ+-Oδ-, when blended with fluorinated benzenes or halide alkane compounds. These intermolecular interactions enable a dynamic Li+-solvent coordination process, thereby promoting the fast Li+ reaction kinetics and suppressing electrode side reactions. Utilizing this molecular-docking electrolyte design strategy, we have developed 25 electrolytes that demonstrate high Li plating/stripping Coulombic efficiencies and promising capacity retentions in both full cells and pouch cells. This work supports the use of the molecular-docking solvation mechanism for designing electrolytes with fast Li+ kinetics for high-voltage Li batteries.

Sustainable and efficient recovery of lithium from rubidium raffinate via solvent extraction

In recent years, with the increasing prevalence of rechargeable lithium-ion batteries in the burgeoning markets of electric vehicles and portable electronic devices, the consumption of lithium batteries has significantly surged. Hence, the efficient development and utilization of associated lithium resources bear paramount significance. This study aims to recover lithium from rubidium raffinate via solvent extraction. A systematic investigation was conducted to examine the effects of various parameters such as organic phase concentration, contact time, and phase ratio (O/A) during the separation process. The results indicated that the organic phase composed of 0.1 mol/L 4,4,4-Trifluoro-1-phenyl-1,3-butanedione (HBTA) and 0.1 mol/L Trioctylphosphine oxide (TOPO) could efficiently extract lithium from the rubidium raffinate. The optimal conditions were observed at a temperature of 20℃, O/A=1, and a contact time of 5 min. After three-stage countercurrent extraction, a lithium extraction rate of 99.24 % could be achieved, with over 95 % of the sodium easily scrubbed by 0.1 mol/L HCl at an O/A=10. With the use of 3 mol/L HCl, stripping efficiency exceeding 99 % could be attained at an O/A=10, consequently a successful preparation of battery-grade lithium carbonate product was achieved. Regeneration experiments confirmed the organic phase's excellent reproducibility efficiency. Slope analysis and density function theory (DFT) simulations indicated that optimal lithium extraction is achieved when HBTA and TOPO are at equal molar concentrations. The proposed process is expected to provide a green and sustainable route for the recovery of associated lithium resources.

Structural engineering on indole derivative for rechargeable organic lithium-ion battery

Structural engineering on indole derivative for rechargeable organic lithium-ion battery

A gel polymer electrolyte obtained from cellulose acetate/polyvinylidene fluoride composite electrospun membrane for safe lithium metal batteries with high-rate capability

Li metal battery is a promising next-generation power storage devices, but faces the serious safety issues caused by the uncontrolled Li dendrite growth and leakage of the flammable organic electrolyte. Herein, a low-cost CA/PVDF (cellulose acetate/polyvinylidene fluoride) composite membrane is prepared via electrospinning technology for safe lithium metal batteries. This membrane (45 μm) exhibits the high porosity (76.9 %) and excellent thermally stability (>180 °C) preventing the short circuit during abuse. The CA/PVDF-based gel polymer electrolyte (GPE), fabricated with CA/PVDF electrospun membrane swelled by carbonate-based organic liquid electrolyte, delivers the ionic conductivity of 1.82 mS cm−1 and Li + transfer number of 0.506, which achieve uniform Li+ ion electrodeposition and inhibit the formation of lithium dendrites. As the results, the symmetrical cell Li/CA/PVDF-based GPE/Li exhibits the impressive reversible Li stripping/plating behavior over 300 h at 1 mA cm−2 with the capacity of 1 mA h cm−2. Furthermore, the assembled LiFePO4/GPE/Li battery exhibits the capacity of 101.2 mA h g−1 at 5C with the capacity retention of 94.6 % after 400 cycles, which exceeds that of traditional liquid electrolytes. This research provides a low-cost gel polymer electrolyte via the electrospinning technique for rechargeable lithium batteries with good electrochemical performance and high security.

Designer Anions for Better Rechargeable Lithium Batteries and Beyond.

Non-aqueous electrolytes, generally consisting of metal salts and solvating media, are indispensable elements for building rechargeable batteries. As the major sources of ionic charges, the intrinsic characters of salt anions are of particular importance in determining the fundamental properties of bulk electrolyte, as well as the features of the resulting electrode-electrolyte interphases/interfaces. To cope with the increasing demand for better rechargeable batteries requested by emerging application domains, the structural design and modifications of salt anions are highly desired. Here, salt anions for lithium and other monovalent (e.g., sodium and potassium) and multivalent (e.g., magnesium, calcium, zinc, and aluminum) rechargeable batteries are outlined. Fundamental considerations on the design of salt anions are provided, particularly involving specific requirements imposed by different cell chemistries. Historical evolution and possible synthetic methodologies for metal salts with representative salt anions are reviewed. Recent advances in tailoring the anionic structures for rechargeable batteries are scrutinized, and due attention is paid to the paradigm shift from liquid to solid electrolytes, from intercalation to conversion/alloying-type electrodes, from lithium to other kinds of rechargeable batteries. The remaining challenges and key research directions in the development of robust salt anions are also discussed. This article is protected by copyright. All rights reserved.

Chemical hazard assessment toward safer electrolytes for lithium-ion batteries.

Commercialization of rechargeable lithium-ion (Li-ion) batteries has revolutionized the design of portable electronic devices and is facilitating the current transition to electric vehicles. The technological specifications of Li-ion batteries continue to evolve through the introduction of various high-risk liquid electrolyte chemicals, yet critical evaluation of the physical, environmental, and human health hazards of these substances is lacking. Using the GreenScreen for Safer Chemicals approach, we conducted a chemical hazard assessment (CHA) of 103 electrolyte chemicals categorized into seven chemical groups: salts, carbonates, esters, ethers, sulfoxides-sulfites-sulfones, overcharge protection additives, and flame-retardant additives. To minimize data gaps, we focused on six toxicity and hazard data sources, including three empirical and three nonempirical predictive data sources. Furthermore, we investigated the structural similarities among selected electrolyte chemicals using the ChemMine tool and the simplified molecular input line entry systeminputs from PubChem to evaluate whether chemicals with similar structures exhibit similar toxicity. The results demonstrate that salts, overcharge protection additives, and flame-retardant additives contain the most toxic components in the electrolyte solutions. Furthermore, carbonates, esters, and ethers account for most flammability hazards in Li-ion batteries. This study supports the complementary use of quantitative structure-activity relationship modelsto minimize data gaps and inconsistencies in CHA. Integr Environ Assess Manag 2024;00:1-14. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Mapping of lithium ion concentrations in 3D structures through development of in situ correlative imaging of X-ray Compton scattering-computed tomography.

Understanding the correlation between chemical and microstructural properties is critical for unraveling the fundamental relationship between materials chemistry and physical structures that can benefit materials science and engineering. Here, we demonstrate novel in situ correlative imaging of the X-ray Compton scattering computed tomography (XCS-CT) technique for studying this fundamental relationship. XCS-CT can image light elements that do not usually exhibit strong signals using other X-ray characterization techniques. This paper describes the XCS-CT setup and data analysis method for calculating the valence electron momentum density and lithium-ion concentration, and provides two examples of spatially and temporally resolved chemical properties inside batteries in 3D. XCS-CT was applied to study two types of rechargeable lithium batteries in standard coin cell casings: (1) a lithium-ion battery containing a cathode of bespoke microstructure and liquid electrolyte, and (2) a solid-state battery containing a solid-polymer electrolyte. The XCS-CT technique is beneficial to a wide variety of materials and systems to map chemical composition changes in 3D structures.

Synergistic Effects of Bisalt Additives in High-Voltage Rechargeable Lithium Batteries.

The stability of high-energy-density lithium metal batteries (LMBs) heavily relies on the composition of the solid electrolyte interphase (SEI) formed on lithium metal anodes. In this study, the inorganic-rich SEI layer was achieved by incorporating bisalts additives into carbonate-based electrolytes. Within this SEI layer, the presence of LiF, polythionate, and Li3N was observed, generated by combining 1.0 м lithium bis(trifluoromethanesulfonyl)imide in ethylene carbonate: ethyl methyl carbonate:dimethyl carbonate in a 1:1:1 volume ratio, with the addition of 2 wt% lithium difluorophosphate and 2 wt% lithium difluoro(oxalato)borate additives (EL-DO). Furthermore, this formulation effectively mitigated corrosion of aluminum current collectors. EL-DO exhibited outstanding performance, including an average coulombic efficiency of 98.2% in Li||Cu cells and a stable discharge capacity of approximately 162 mAh g-1 after 200 cycles in a Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) configuration. Moreover, EL-DO displayed the potential to enhance the performance not only of LMBs but also of lithium-ion batteries. In the case of Gr||NCM811 cell using EL-DO, it consistently maintained high discharge capacities, even achieving around 135 mAh g-1 after the 100th cycle, surpassing the performance of other electrolytes. This study underscores the synergistic impact of bisalts additives in elevating the performance of lithium batteries.

A Naphthalenetetracarboxdiimide‐Containing Covalent Organic Polymer: Preparation, Single Crystal Structure and Battery Application

AbstractInspired by dative boron‐nitrogen (B←N) bonds proven to be the promising dynamic linkage for the construction of crystalline covalent organic polymers/frameworks (COPs/COFs), we employed 1,4‐bis(benzodioxaborole) benzene (BACT) and N,N′‐Di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxdiimide (DPNTCDI) as the corresponding building blocks to construct a functional COP (named as CityU‐25), which had been employed as an anode in rechargeable lithium ion batteries. CityU‐25 displayed an excellent reversible lithium storage capability of 455 mAh/g after 170 cycles at 0.1 A/g, and an impressive one of 673 mAh/g after 720 cycles at 0.5 A/g. These findings suggest that CityU‐25 is a standout candidate for advanced battery technologies, highlighting the potential application of this type of materials.

A Naphthalenetetracarboxdiimide-Containing Covalent Organic Polymer: Preparation, Single Crystal Structure and Battery Application.

Inspired by dative boron-nitrogen (B←N) bonds proven to be the promising dynamic linkage for the construction of crystalline covalent organic polymers/frameworks (COPs/COFs), we employed 1,4-bis(benzodioxaborole) benzene (BACT) and N,N'-Di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxdiimide (DPNTCDI) as the corresponding building blocks to construct a functional COP (named as CityU-25), which had been employed as an anode in rechargeable lithium ion batteries. CityU-25 displayed an excellent reversible lithium storage capability of 455 mAh/g after 170 cycles at 0.1 A/g, and an impressive one of 673 mAh/g after 720 cycles at 0.5 A/g. These findings suggest that CityU-25 is a standout candidate for advanced battery technologies, highlighting the potential application of this type of materials.

Tartaric Acid Cross-Linking Polyvinyl Alcohol as Degradable Separators for Rechargeable Lithium Ion Batteries.

The escalating focus on environmental concerns and the swift advancement of eco-friendly biodegradable batteries raises a pressing demand for enhanced material design in the battery field. The traditional polypropylene (PP) that is monopolistically utilized in the commercial LIBs is hard to recycle. In this work, we prepare a novel water degradable separators via the cross-linking of polyvinyl alcohol (PVA) and dibasic acid (tartaric acid, TA). Through the integration of non-solvent liquid-phase separation, we successfully produced a thermally stable PVA-TA membrane with tunable thickness and a high level of porosity. These specially engineered PVA-TA separators were implemented in LiFePO4 (LFP)|separator|Li cells, resulting in superior multiplicative performance and achieving a capacity of 88 mAh g-1 under 5 C. Additionally, the straightforward small molecule cross-linking technique significantly reduced the crystalline region of the polymer, thereby enhancing ionic conductivity. Notably, after cycling, the PVA-TA separators can be easily dissolved in 95 °C hot water, enabling its reutilization for the production of new PVA-TA separators. Therefore, this work introduces a novel concept to design green and sustainable separators for recyclable lithium batteries.

First-principles Study of Solvent Polarity Effects in the Menshutkin Reaction

First-principles Study of Solvent Polarity Effects in the Menshutkin Reaction

Influence of iron phosphate on the performance of lithium iron phosphate as cathodic materials in rechargeable lithium batteries

Influence of iron phosphate on the performance of lithium iron phosphate as cathodic materials in rechargeable lithium batteries

3D-printed portable device for illicit drug identification based on smartphone-imaging and artificial neural networks

In this manuscript, a 3D-printed analytical device has been successfully developed to classify illicit drugs using smartphone-based colorimetry. Representative compounds of different families, including cocaine, 3,4-methylenedioxy-methamphetamine (MDMA), amphetamine and cathinone derivatives, pyrrolidine cathinones, and 3,4-methylenedioxy cathinones, have been analyzed and classified after appropriate reaction with Marquis, gallic acid, sulfuric acid, Simon and Scott reagents. A picture of the colored products was acquired using a smartphone, and the corrected RGB values were used as input data in the chemometric treatment. ANN using two active layers of nodes (6 nodes in layer 1 and 2 nodes in layer 2) with a sigmoidal transfer function and a minimum strict threshold of 0.50 identified illicit drug samples with a sensitivity higher than 83.4 % and a specificity of 100 % with limits of detection in the microgram range. The 3D printed device can operate connected to a rechargeable lithium-ion cell portable battery, is inexpensive, and requires minimal training. The analytical device has been able to discriminate the analyzed psychoactive substances from cutting and mixing agents, being a useful tool for law enforcement agents to use as a screening method.

Polyester-enhanced poly (cyclic carbonate-fluoride)-based polymer electrolyte for stable circulating solid lithium batteries

Polymer solid-state electrolytes have become one of the promising materials for constructing solid-state lithium batteries due to their excellent processability and good compatibility with electrode interfaces. However, their limited electrochemical performance and mechanical strength have hindered their widespread application. Through the adoption of an in-situ thermal curing method, we successfully prepared a poly(carbonate-fluoride) solid-state electrolyte, utilizing a polyester separator with abundant polar groups as a reinforcing framework. The introduction of ionic liquid into the solid polymer electrolyte not only enhances the mobility of polymer chain segments to improve ionic conductivity but also, in synergy with trifluoromethyl, promotes lithium salt dissociation while restricting the migration of lithium salt anions. Additionally, their reaction with the lithium metal anode generates the LiF-rich SEI, regulating the deposition of lithium dendrites. The resulting 31VPIF/OZ exhibited outstanding ionic conductivity (3.58 × 10−4 S cm−1 at 25 °C), Li-ion migration number (0.52), and electrochemical window (5.4 V). Li | 31VPIF/OZ | Li battery cycled for 1000 h at 0.1 mA cm−2 without short-circuiting. Importantly, Li | | LiFePO4 battery demonstrated a high capacity retention rate of 91.5 % after 600 cycles at 0.5C (25 °C). Thus, through the synergistic interplay of polymer structure design and fillers, we have successfully achieved stable cycling in solid-state lithium batteries, providing robust support for their application in rechargeable lithium battery technology.

Homogenous coating of Li+ conductive Li5AlO4 on single-crystalline nonstoichiometric Li1.04Ni0.92Al0.04O2 for rechargeable lithium-ion batteries

Cobalt-free, nickel-rich LiNi1-xAlxO2 (x ≤ 0.1) is an attractive cathode material because of high energy density and low cost but suffers from severe structural degradation and poor rate performance. In this study, we propose a molten salt-assisted synthesis in combination with a Li-refeeding induced aluminum segregation strategy to prepare Li5AlO4-coated single-crystalline slightly Li-rich Li1.04Ni0.92Al0.04O2. The symbiotic formation of Li5AlO4 from reaction between molten lithium hydroxide and doped aluminum in the bulk ensures a high lattice matching between the Ni-rich oxide and the homogenous conductive Li5AlO4 that permits high Li+ conductivity. Benefiting from mitigated undesirable side reactions and phase evolution, the Li5AlO4-coated single-crystalline Li1.04Ni0.92Al0.04O2 delivers a high specific capacity of 220.2 mA h g−1 at 0.1 C and considerable rate capability (182.5 mA h g−1 at 10 C). Besides, superior capacity retention of 90.8% is obtained at 1/3 C after 100 cycles in a 498.1 mA h pouch full cell. Furthermore, the particulate morphology of Li1.04Ni0.92Al0.04O2 remains intact after cycling at a cutoff voltage of 4.3 V, whereas slightly Li-deficient Li0.98Ni0.97Al0.05O2 features intragranular cracks and irreversible lattice distortion. The results highlight the value of molten salt-assisted synthesis and Li-refeeding induced elemental segregation strategy to upgrade Ni-based layered oxide cathode materials for advanced Li-ion batteries.

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.

From Inorganic to Organic Iodine: Stabilization of I+ Enabling High-Energy Lithium-Iodine Battery.

Organic materials have been considered a class of promising cathodes for metal-ion batteries because of their sustainability in preparation and source. However, organic batteries with high energy density and application potential require high discharge voltage, multielectron transfer, and long cycling performance. Here, we report an exceptional lithium-iodine (Li//I2) battery, in which the organic iodine (BPD-HI) cathode formed by the Lewis acid-base coordination between hydroiodic acid (HI) and 4,4'-bipyridine (BPD) allows 2e- transfer via the I-/I0 and I0/I+ redox couples. The I+ stabilized by BPD exhibits a high discharge voltage plateau at ∼3.4 V. Remarkably, from inorganic to organic iodine, it realizes a 2-fold increase in the achieved capacity, up to ∼400 mA h gI-1 (Theor. 422 mA h gI-1 and 245.6 mA h g-1 based on the mass of BPD-HI), and an over 2-fold energy density, reaching 1160 W h kgI-1 (Theor. 1324 W h kgI-1). More importantly, a capacity retention rate of 85% over 850 cycles is attained for the Li//BPD-HI battery at a current density of 2 A gI-1. This facile strategy enables positively charged I+ to be electrochemically active in a rechargeable lithium battery. The new redox chemistry discovered provides new insights for developing organic batteries with high energy density.

The role of graphene in SnS2@Graphene for rechargeable lithium batteries: A view from the electronic structure

Based on the first-principles study, the adsorption and electron transfer properties of Li atom at different sites of SnS2 monolayer, SnS2@Graphene 2D-nanocomposite are analyzed. The differential charge density and density of states (DOS) analysis show that the graphene substrate as an electron donor can change the 2D-nanocomposite from a semiconductor to a metal, and reduce the adsorption energy of Li atom by decreasing the charge transferring from Li atom to SnS2. This indicates that graphene substrate is beneficial for improving the performance of SnS2@Graphene. Meanwhile, the Li atoms tend not to cluster on the SnS2@Graphene 2D-nanocomposite, which is useful to prolong the lifespan of the SnS2@Graphene. The functionality of graphene in SnS2@Graphene 2D-nanocomposite is proved by other electron donor substrates, such as a two-H-atom model and a Sn (111) substrate model. All the results indicate that the graphene, as an electron donor in SnS2@Graphene 2D-nanocomposite, plays a key role in improving the performance of SnS2 in rechargeable lithium batteries.