Thin Electrolyte Research Articles

A novel symmetrical SOFC with thin BZCY electrolyte and PBFNCM-BZCY electrodes for electricity and ethylene co-production through ethane dehydrogenation

A novel symmetrical SOFC with thin BZCY electrolyte and PBFNCM-BZCY electrodes for electricity and ethylene co-production through ethane dehydrogenation

The Impact of Dual-Salt Electrolyte with Low Fluorine Content on the Performance of Layered Transition Metal Oxides for Sodium-Ion Batteries.

In this work, the characterization of novel electrolytes based on the combination of propylene carbonate(PC)solvent with sodium bis(fluorosulfonyl)imide(NaFSI)and sodium difluoro(oxalato)borate(NaDFOB), as well as their application in sodium-ion batteries(SIBs) is presented. The results show that dual-salt electrolytes have a wide electrochemical stability window, excellent transport properties, and mostly suppress anodic dissolution. When combined with P2-Na2/3Al1/9Fe1/9Mn2/3Ni1/9O2(P2-AFMNO) cathode electrode for SIBs operating at 4.3V vs Na+/Na, they enable high performance and stability. XPS investigation revealed that this performance is related to the formation of a thin and homogeneous cathode electrolyte interphase (CEI) at the electrode surface.

Robust interface and reduced operation pressure enabled by co-rolling dry-process for stable all-solid-state batteries

The dry-process is a sustainable and promising fabrication method for all-solid-state batteries by eliminating solvents. However, a pragmatic fabrication design for thin and robust solid-state electrolyte (SSE) layers has not been established. Herein, we report a dry-process approach that enhances mechanical stability of SSE layers from film fabrication to cell operation. By co-rolling thick SSE and positive electrode feeds, a uniform, thin SSE layer (50 µm) and a high loading positive electrode layer (5 mAh cm−2) with high active material ratio (80 wt%) are simultaneously achieved. This SSE-positive electrode integrated film exhibits enhanced physical properties and cyclability (> 80% retention after 500 cycles) at low stack pressure (2 MPa) compared to the freestanding counterparts, attributed to reinforced and intimate SSE-positive electrode interface constructed during co-rolling process. Additionally, an all-solid-state pouch cell with high stack-level specific energy (310 Wh kg−1) and energy density (805 Wh L−1) operating at 30 °C and 5 MPa is demonstrated.

Enabling durable electrolyte-free silicon anode in thin sulfide electrolyte membrane-based all-solid-state lithium batteries via failure mechanism study

Enabling durable electrolyte-free silicon anode in thin sulfide electrolyte membrane-based all-solid-state lithium batteries via failure mechanism study

Electronic/Ionic Conductive MoS6-Based Composites for All-Solid-State Lithium Batteries.

The transition metal polysulfide cathodes driven by anion redox show high reversible specific capacity, demonstrating great application potential in all-solid-state lithium batteries (ASSLBs). However, their inferior electron/ion conductivities and large volume expansion are critical challenges. In this work, the MoS6-10%rGO@15%Li7P3S11 cathode material is synthesized and utilized in ASSLBs. The cooperation of reduced graphene oxide (rGO) can significantly mitigate the volume changes of MoS6 during the cycling and enhance electronic conductivity of the cathode from 2.56 × 10-8 S cm-1 for MoS6 to 0.28 S cm-1 for MoS6-10%rGO. Besides, a thin Li7P3S11 solid electrolyte layer is in situ coated on the surface of MoS6-10%rGO, realizing intimate contact. Meanwhile, the ionic conductivity of the MoS6-10%rGO@15%Li7P3S11 composite reaches 8.4 × 10-4 S cm-1, 3 orders of magnitude greater than that of MoS6 with 2.8 × 10-7 S cm-1. The ASSLBs utilizing the MoS6-10%rGO@15%Li7P3S11 cathode deliver an initial discharge specific capacity of 1111.97 mAh g-1 at 0.1 A g-1. Notably, it achieves a reversible ultrahigh energy density of 1750.94 Wh kg-1 based on the active material at the second cycle. Furthermore, the batteries possess superior cycling stability, maintaining a discharge specific capacity of 729.53 mAh g-1 after 500 cycles at 0.5 A g-1. This work provides a high-energy-density active material for ASSLBs.

Redefining closed pores in carbons by solvation structures for enhanced sodium storage

Closed pores are widely accepted as the critical structure for hard carbon negative electrodes in sodium-ion batteries. However, the lack of a clear definition and design principle of closed pores leads to the undesirable electrochemical performance of hard carbon negative electrodes. Herein, we reveal how the evolution of pore mouth sizes determines the solvation structure and thereby redefine the closed pores. The precise and uniform control of the pore mouth sizes is achieved by using carbon molecular sieves as a model material. We show when the pore mouth is inaccessible to N2 but accessible to CO2 molecular probes, only a portion of solvent shells is removed before entering the pores and contact ion pairs dominate inside pores. When the pore mouth is inaccessible to CO2 molecular probes, namely smaller than 0.35 nm, solvent shells are mostly sieved and dominated anion aggregates produce a thin and inorganic NaF-rich solid electrolyte interphase inside pores. Closed pores are accordingly redefined, and initial coulombic efficiency, cycling and low-temperature performance are largely improved. Furthermore, we show that intrinsic defects inside the redefined closed pores are effectively shielded from the interfacial passivation and contribute to the increased low-potential plateau capacity.

Disorder-driven sintering-free garnet-type solid electrolytes

Oxide ceramic electrolytes for realization of high-energy lithium metal batteries typically require high-temperature processes to achieve the desired phase formation and inter-particle sintering. However, such high-temperature processing can lead to compositional changes or mechanical deformation, compromising material reliability. Here, we introduce a disorder-driven, sintering-free approach to synthesize garnet-type solid electrolyte via the creation of an amorphous matrix followed by a single-step mild heat-treatment. The softened mechanical property (yield pressure, Py = 359.8 MPa) of disordered base materials enables the facile formation of a dense amorphous matrix and the preserving of inter-particle connectivity during crystallization. The formation of the cubic-phase garnet is triggered at a lowered temperature of 350 °C, achieving a Li+ ionic conductivity of 1.8 × 10–4 S/cm at 25 °C through a single-step mild heat treatment at 500 °C. The disorder-driven garnet solid electrolyte exhibits electrochemical performance comparable to conventional garnet solid electrolyte sintered at >1100 °C. These findings will promote the fabrication of uniform, thin, and wide solid electrolyte membranes, which is a significant hurdle in the commercialization of oxide-based lithium metal batteries, and demonstrate the untapped capabilities of garnet-type oxide solid electrolytes.

Evaluation of Electropolymerization as a Versatile Approach for Applying Conformal Polymer Electrolyte Films on Complex Micro‐Scale Silicon Architectures

AbstractApplication of conformal thin polymer electrolyte coatings on architecturally complex conductive electrode surfaces in various microdevices presents a significant technical challenge using conventional thin‐film deposition techniques. In this study, electro‐grafting combined with electropolymerization is investigated as a more versatile technique for applying these electrolyte coatings in order to advance the development of 3D microbatteries. Gel polymer electrolyte (GPE) films of several micrometers of thickness are electrochemically polymerized on cylindrical silicon micropillars employed as the anode in a lithium‐ion battery. This in‐situ electrochemical method allowed greater control of polymer film formation by applying a suitably negative potential for a designated duration. Scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy is used to analyze the surface and cross sections of polymer‐coated silicon micropillars to evaluate film formation as a function of applied potential and electrodeposition time. Discrete robust GPE samples, with the same composition as those prepared by electropolymerization, are also prepared to simplify characterization. The polymer electrolyte exhibits good thermal and electrochemical stability, high discharge capacity, and excellent capacity retention at high rates when evaluated in a coin cell. These results suggest that the electrochemical electrolyte coating technique holds promise for fabricating small‐scale lithium‐ion batteries with complex electrode architectures.

Recent progress of thin solid-state electrolytes and applications for solid-state lithium pouch cells

Recent progress of thin solid-state electrolytes and applications for solid-state lithium pouch cells

Electron Density Engineering at the Bond Critical Points in Solvation Sheath of Sodium Ions for High-Rate Hard Carbon in Ether-Based Electrolyte.

Rationally designing the electrolyte system toward improving the electrochemical performance, especially the rate capability, of sodium ion batteries (SIBs) is very important for accelerating their large-scale commercialization. Herein, it is shown that by refining the molar ratio of two ether solvents, namely dimethoxyethane (DME) and 2-methyl tetrahydrofuran (MeTHF), a binary solvent electrolyte system forms a sodium ion solvation structure that facilitates high rate charge/discharge of hard carbon (HC) electrodes. It is demonstrated that the boosted rate capability can be attributed to the enhanced sodium ion transportation and desolvation kinetics, resulting from the participation of weak-coordinating MeTHF molecule with low steric hindrance in the sodium ion solvation sheath, which weakens the interaction between sodium ion and solvent molecules/anions through electron density regulation at the bond critical points (BCPs). The thin and uniform solid electrolyte interphase film on HC electrodes formed in such an ether-based electrolyte is also beneficial for improving the rate performance and cycling stability. The results of the present study shed more light on how the electron density engineering at the BCPs in sodium ion solvation sheath affects the rate capability of HC electrodes and promote its practical application prospect in future sodium-based battery chemistries.

Enhancing the Interfacial Stability of Thin Solid Polymer Electrolyte with Fluorinated Covalent Organic Framework Nanosheets.

Thin poly(ethylene oxide) (PEO)-based electrolytes with higher energy density face challenges such as low ionic conductivity, deterioration of lithium dendrites, and severe side reactions. To address these issues, a surface modification strategy was developed to enhance the electrode-electrolyte interfacial stability by introducing fluorinated covalent organic framework nanosheets (CONs) to construct a thin PEO-based electrolyte with a mere 14 μm thickness. Characterization and DFT calculation indicated that the CON layer promotes concentration enrichment and averaging of free Li+ and mitigates side reactions at the interface. The electrode/electrolyte interface stability is significantly improved compared to the unmodified group (Li symmetric cells stabilized for more than 1000 h, and the full cell of LiFePO4∥Li exhibited a satisfactory capacity retention of 97.3% at 0.5 C after 150 cycles at 60 °C. This interface modification strategy provides a valuable reference for applying thin polymer electrolytes in high-energy solid-state lithium metal batteries.

A thin and homogeneous solid electrolyte interface enriched with ZnF2 and ZnS for highly reversible zinc batteries

A thin and homogeneous solid electrolyte interface enriched with ZnF2 and ZnS for highly reversible zinc batteries

Comparative Study of Volatile Corrosion Inhibitors in Various Electrochemical Setups

Volatile corrosion inhibitors (VCIs) are increasingly used in closed systems affected by atmospheric corrosion. In order to achieve a satisfactory level of protection, an inhibitor must be present in a sufficient concentration that should be determined experimentally. Electrochemical measurements are indispensable in corrosion studies examining the protection efficiency of corrosion inhibitors. Volatile corrosion inhibitors are often examined by electrochemical measurements conducted in a bulk of electrolyte, although they protect metal surfaces from atmospheric corrosion where a thin film of electrolyte is present. The aim of this work is to study the protection of carbon steel by two VCIs on different types of electrodes that allow electrochemical tests in a thin electrolyte film and to compare the obtained results with those obtained in a larger volume in a classical electrochemical cell. For this purpose, disc and comb-like electrodes are used. The investigations are carried out in two corrosion media simulating either a marine or urban polluted atmosphere. Studies are performed on low-carbon S235JR steel, which is typically used for crude oil tank bottoms that often suffer from atmospheric corrosion and are increasingly protected by VCIs. Two benzoate-based VCIs recommended for such application are selected for this study.

Toward Higher Energy Density All‐Solid‐State Batteries by Production of Freestanding Thin Solid Sulfidic Electrolyte Membranes in a Roll‐to‐Roll Process

AbstractAll‐solid‐state batteries (SSB) show great promise for the advancement of high‐energy batteries. To maximize the energy density, a key research interest lies in the development of ultrathin and highly conductive solid electrolyte (SE) layers. In this work, thin and flexible sulfide solid electrolyte membranes are fabricated and laminated onto a non‐woven fabric using a scalable and solvent‐free, continuous roll‐to‐roll process (DRYtraec). These membranes show significantly improved tensile strength compared to unsupported sheets, which facilitates cell assembly and allows a continuous component production using a single‐step calendering process. By tuning the thickness, densified membranes with thicknesses ranging from 40 to 160 µm are obtained after a compression step. The resulting SE membranes retain a high ionic conductivity (1.6 mS cm−1) at room temperature. An excellent rate capability is demonstrated in a SSB pouch cell with a Li2O–ZrO2‐coated LiNi0.9C0.05Mn0.05O2 cathode, a 55 µm thin SE membrane, and a columnar silicon anode fabricated by a scalable physical vapor deposition process. At stack level, a promising energy density of 673 Wh L−1 (and specific energy of 247 Wh kg−1) is achieved, showcasing the potential for high energy densities by reducing the SE membrane thickness while retaining good mechanical properties.

A Universal Design of Lithium Anode via Dynamic Stability Strategy for Practical All-Solid-State Batteries.

All-solid-state Li-metal battery (ASSLB) chemistry with thin solid-state electrolyte (SSE) membranes features high energy density and intrinsic safety but suffers from severe dendrite formation and poor interface contact during cycling, which hampers the practical application of rechargeable ASSLB. Here, we propose a universal design of thin Li-metal anode (LMA) via a dynamic stability strategy to address these issues. The ultra-thin LMA (20 μm) is in situ constructed with uniform highly Li-ion conductive solid-electrolyte interphase and composite-polymer interphase (CPI) via electroplating process. As a result, the passivation layer with poor Li-ion conduction on Li anode can be dissolved and small surface resistance can be achieved due to the good compatibility of CPI to SSEs. The cycling of Li symmetric cell with Li6PS5Cl thin film electrolyte (<100 μm) shows a high critical current density of >2.0 mA cm-2 with excellent cycling stability at 1.0 mA cm-2. The ASSLBs paring with Ni-rich LiNi0.6Mn0.2Co0.2O2 cathode demonstrated the feasibility of engineered LMA design by presenting good rate capability from 0.1 C to 1.0 C at room temperature, as well as long-term cycling stability (81 % retention after 100 cycles). This work represents a general pathway to make thin dendrite-free LMA available for high-energy-density ASSLBs.

A Universal Design of Lithium Anode via Dynamic Stability Strategy for Practical All‐Solid‐State Batteries

AbstractAll‐solid‐state Li‐metal battery (ASSLB) chemistry with thin solid‐state electrolyte (SSE) membranes features high energy density and intrinsic safety but suffers from severe dendrite formation and poor interface contact during cycling, which hampers the practical application of rechargeable ASSLB. Here, we propose a universal design of thin Li‐metal anode (LMA) via a dynamic stability strategy to address these issues. The ultra‐thin LMA (20 μm) is in situ constructed with uniform highly Li‐ion conductive solid‐electrolyte interphase and composite‐polymer interphase (CPI) via electroplating process. As a result, the passivation layer with poor Li‐ion conduction on Li anode can be dissolved and small surface resistance can be achieved due to the good compatibility of CPI to SSEs. The cycling of Li symmetric cell with Li6PS5Cl thin film electrolyte (&lt;100 μm) shows a high critical current density of &gt;2.0 mA cm−2 with excellent cycling stability at 1.0 mA cm−2. The ASSLBs paring with Ni‐rich LiNi0.6Mn0.2Co0.2O2 cathode demonstrated the feasibility of engineered LMA design by presenting good rate capability from 0.1 C to 1.0 C at room temperature, as well as long‐term cycling stability (81 % retention after 100 cycles). This work represents a general pathway to make thin dendrite‐free LMA available for high‐energy‐density ASSLBs.

Investigation of MgO additives on microstructure and properties of thin LLZO electrolytes for all-solid-state batteries

To realize high-energy density lithium lanthanum zirconate (LLZO)-based solid-state batteries (SSB), LLZO electrolytes should be fabricated with low thickness and high mechanical strength.

Thin Film Type Solid Electrolyte based on PVDF-HFP/LLZO Composite with Enhanced Electrochemical Performance

Thin Film Type Solid Electrolyte based on PVDF-HFP/LLZO Composite with Enhanced Electrochemical Performance

EVIDENCE FOR ADRENAL DYSFUNCTION CONTRIBUTING TO PERACUTE MORTALITY SYNDROME IN RED PANDA (AILURUS FULGENS).

Red pandas (Ailurus fulgens) are endangered with extinction due to deforestation and habitat fragmentation. Reported causes of unexpected death in managed red pandas include kidney, liver, gastrointestinal, and cardiac disease. A previously undetailed syndrome, red panda peracute mortality syndrome, may be emerging, as red pandas have died unexpectedly, with no clear cause of death identified at necropsy. This case series describes the clinical and postmortem findings of five red pandas at Brookfield Zoo with abnormal adrenal size and associated histologic lesions as possible contributing factors to acute death. Antemortem clinical signs consisted of thin body condition, vomiting, intermittent diarrhea, neck ventroflexion, ataxia, and electrolyte abnormalities. Mortality may have been due to abnormal adrenal function, resulting in fatal electrolyte disturbances. Antemortem adrenocorticotropic hormone (ACTH) stimulation tests indicated an inappropriate response to ACTH with persistently low cortisol and aldosterone levels after cosyntropin administration. Clinical improvement was seen when red pandas were provided steroids, but all cases were eventually fatal. Further study is needed to understand red panda peracute mortality syndrome and associated adrenal dysfunction.

Mechanisms of Secondary Spreading and Micro Droplet Formation on Steel

Abstract A new theory for secondary spreading based on the wetting theory of thin films is presented. It explains how micro droplets within the spreading zone and the primary droplet retain their shape, although connected by a thin electrolyte film and how humidity and salt concentration affect the growth rate of micro droplets. The trigger for secondary spreading, polarization or alkalization, is identified by using droplets of sodium hydroxide solution. Secondary spreading thus occurs on steel from pH 13.5 without corrosion or external polarization. The limiting pH value found explains why secondary spreading on steel only occurs when certain salts are used. &amp;#xD;The effect of the substrate is investigated by changing the microstructure of the steel. By comparing the sizes of micro droplets and micro structural phases and by scanning electron microscopy/energy-dispersive X-ray analysis measurements of the spreading zone, the existence of an electrolyte film connecting the micro droplets is supported. Ecorr potential profiles of secondary spreading droplets of sodium chloride solution on steel acquired by means of SKP are used to assess the contribution of secondary spreading to the total corrosion current, which is estimated to be low compared to that of the cathodic zone at the edge of the droplet