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At least 109 records · Page 6

Nanocomposite Ionogel Electrolytes for Solid‐State Rechargeable Batteries

Abstract Ionogels composed of ionic liquids and gelling solid matrices offer several advantages as solid‐state electrolytes for rechargeable batteries, including safety under diverse operating conditions, favorable electrochemical and thermal properties, and wide processing compatibility. Among gelling solid matrices, nanoscale materials have shown particular promise due to their ability to concurrently enhance ionogel mechanical properties, thermal stability, ionic conductivity, and electrochemical stability. These beneficial attributes suggest that ionogel electrolytes are not only of interest for incumbent lithium‐ion batteries but also for next‐generation rechargeable battery technologies. Herein, recent advances in nanocomposite ionogel electrolytes are discussed to highlight their advantages as solid‐state electrolytes for rechargeable batteries. By exploring a range of different nanoscale gelling solid matrices, relationships between nanoscale material structure and ionogel properties are developed. Furthermore, key research challenges are delineated to help guide and accelerate the incorporation of nanocomposite ionogel electrolytes in high‐performance solid‐state rechargeable batteries.

Hyun, Woo Jin↗

Layered Heterostructure Ionogel Electrolytes for High‐Performance Solid‐State Lithium‐Ion Batteries

Abstract Ionogel electrolytes based on ionic liquids and gelling matrices offer several advantages for solid‐state lithium‐ion batteries, including nonflammability, wide processing compatibility, and favorable electrochemical and thermal properties. However, the absence of ionic liquids that are concurrently stable at low and high potentials constrains the electrochemical windows of ionogel electrolytes and thus their high‐energy‐density applications. Here, ionogel electrolytes with a layered heterostructure are introduced, combining high‐potential (anodic stability: >5 V vs Li/Li + ) and low‐potential (cathodic stability: <0 V vs Li/Li + ) imidazolium ionic liquids in a hexagonal boron nitride nanoplatelet matrix. These layered heterostructure ionogel electrolytes lead to extended electrochemical windows, while preserving high ionic conductivity (>1 mS cm −1 at room temperature). Using the layered heterostructure ionogel electrolytes, full‐cell solid‐state lithium‐ion batteries with a nickel manganese cobalt oxide cathode and a graphite anode are demonstrated, exhibiting voltages that are unachievable with either the high‐potential or low‐potential ionic liquid alone. Compared to ionogel electrolytes based on mixed ionic liquids, the layered heterostructure ionogel electrolytes enable higher stability operation of full‐cell lithium‐ion batteries, resulting in significantly enhanced cycling performance.

Hyun, Woo Jin↗

Enabling high areal capacity for Co-free high voltage spinel materials in next-generation Li-ion batteries

The rapidly growing technological demand for lithium-ion batteries has prompted the development of novel cathode materials with high energy density, low cost, and improved safety. High voltage spinel, LiNi 0.5 Mn 1.5 O 4 (LNMO), is one of the most promising candidates yet to be commercialized. The two primary obstacles for this material are the inferior electronic conductivity and fast capacity degradation in full cells due to the high operating voltage. By systematically addressing these limitations, we successfully develop a thick LNMO electrode with areal capacity loadings up to 3 mAh·cm –2 . The optimized thick electrode is paired with a commercial graphite anode at both the coin cell and pouch cell level, achieving a full cell capacity retention as high as 72% and 78%, respectively, after 300 cycles. We attribute this superior cycling stability to careful optimizations of cell components and testing conditions, with a specific focus improving electronic conductivity and high voltage compatibility. These results suggest precise control of materials quality, electrode architecture and electrolyte optimization can soon support the development of a cobalt-free battery system based on a thick LNMO cathode (>4 mAh·cm 2 ), which will eventually meet the needs of next-generation Li-ion batteries with reduced cost, improved safety, and assured sustainability.

25 ENERGY STORAGE↗

A Micelle Electrolyte Enabled by Fluorinated Ether Additives for Polysulfide Suppression and Li Metal Stabilization in Li-S Battery

The Li-S battery is a promising next-generation technology due to its high theoretical energy density (2600 Wh kg -1 ) and low active material cost. However, poor cycling stability and coulombic efficiency caused by polysulfide dissolution have proven to be major obstacles for a practical Li-S battery implementation. In this work, we develop a novel strategy to suppress polysulfide dissolution using hydrofluoroethers (HFEs) with bi-functional, amphiphlic surfactant-like design: a polar lithiophilic "head" attached to a fluorinated lithiophobic "tail." A unique solvation mechanism is proposed for these solvents whereby dissociated lithium ions are readily coordinated with lithiophilic "head" to induce self-assembly into micelle-like complex structures. Complex formation is verified experimentally by changing the additive structure and concentration using small angle X-ray scattering (SAXS). These HFE-based electrolytes are found to prevent polysulfide dissolution and to have excellent chemical compatibility with lithium metal: Li||Cu stripping/plating tests reveal high coulombic efficiency (>99.5%), modest polarization, and smooth surface morphology of the uniformly deposited lithium. Li-S cells are demonstrated with 1395 mAh g-1 initial capacity and 71.9% retention over 100 cycles at >99.5% efficiency-evidence that the micelle structure of the amphiphilic additives in HFEs can prohibit polysulfide dissolution while enabling facile Li + transport and anode passivation.

25 ENERGY STORAGE↗

Optimization of catholyte for halide-based all-solid-state batteries

Halide solid electrolytes gain significant attention due to their high ionic conductivity, low processing temperature, dry air compatibility, and high-voltage stability. However, low cathode active material (CAM) loading in the composite cathode constrains the realization of high energy density for halide-based all-solid-state batteries. In this study, three halide materials, raw Li 3 YBrCl 5 (LYBC-R, <30μm), milled LYBC (LYBC-M, <5 μm) and freeze-dried Li 3 InCl 6 (LIC, <500 nm), were used as catholytes, combined with LYBC-M as the electrolyte and LiIn alloy as the anode. The CAM:catholyte ratio was investigated as well as stack pressure and operating temperature. Our study demonstrates that particle size of the catholyte plays an important role only for high CAM loading or high C-rate cycling. At moderate CAM loading (65 and 70wt% LiNi 0.83 Mn 0.06 Co 0.11 O 2 ) and 0.1 C-rate, all the three catholytes perform well, providing initial discharge capacities >177 mAh/g. At high CAM loading (85wt%) and 0.1 C-rate, a cathode with the nano-scale LIC catholyte provides discharge capacity of 175 mAh/g, while the larger particle size catholytes suffer significantly reduced capacity. Both LYBC and LIC catholytes provided capacity retention >80% after 200 cycles at 0.5C. These results imply that cathode particle size is critically important for performance at high CAM loading. Furthermore, both electrolyte and cathode were tape cast to scale up size and prepare realistic layer thicknesses. A small amount of binder was used in both layers, to balance the electrochemical performance and mechanical properties. Further, the discharge capacity of a tape cell was 152mA h/g at 0.1C with a capacity retention of 81.8% after 20 cycles at 0.5C. The results demonstrate the excellent performance of LYBC as an electrolyte, and provide guidance for halide-based cathode design.

25 ENERGY STORAGE↗

Advanced Low-Flammable Electrolytes for Stable Operation of High-Voltage Lithium-Ion Batteries

Despite being an effective flame retardant, trimethyl phosphate (TMP a ) is generally considered as an unqualified solvent for fabricating electrolytes used in graphite (Gr) based lithium ion batteries as it readily leads to Gr exfoliation and cell failure. In this work, by adopting the unique solvation structure of localized high-concentration electrolyte (LHCE) to TMP a and tuning the composition of the solvation sheath via electrolyte additive, excellent electrochemical performance can be achieved with TMPa based electrolytes in Gr||LiNi 0.8 Mn 0.1 Co 0.1 O 2 cells. After 500 charge/discharge cycles within the voltage range of 2.5-4.4 V, the batteries containing TMPa based LHCEs with proper additive can achieve a capacity retention of 85.4%, being significantly higher than cells using a LiPF 6 -organocarbonates baseline electrolyte (75.2%). Meanwhile, due to the flame retarding effect of TMP a , TMP a based LHCEs exhibit significantly reduced flammability compared with the conventional LiPF 6 -organocarbonates electrolyte.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Impact of Salt Chemistry and Interlayer Architecture on Solid Electrolyte Interphase Composition and Performance

Reversible lithium metal anodes require interphases that are chemically stable, mechanically robust, and compatible with scalable processing. Here, we use slot-die-coated, salt-rich PEO interlayers to design SEI nanolayers on Cu current collectors and isolate how salt anion chemistry controls interphase composition and lithium plating/stripping behavior in architectures relevant to Li plating and anode-free cells. Mesoscale modeling shows that dendrite initiation at SEI defects is governed by a tradeoff among interphase thickness, ionic conductivity, and stiffness through defect-driven current focusing, motivating controlled formation from thin precursor layers. Using UHV-transferred XPS and ToF-SIMS depth profiling after controlled Li deposition, we find that fluorinated sulfonylimide salts (LiTFSI, LiFSI) form mixed inorganic/organic interphases containing LiF and PEO-derived alkoxides, with LiFSI producing a more LiF-dominant Li-facing surface than LiTFSI under identical conditions. In contrast, LiNO 3 -containing interlayers yield a comparatively thick nitrate-derived interphase that reduces upon Li contact to an N-rich inorganic layer (Li–N/N 3− , LiN x O y ). In Cu| |Li cells, these designed interlayers reduce interfacial resistance and improve Coulombic efficiency (CE) and critical current density (CCD) relative to uncoated controls, with LiFSI- and LiNO 3 -based interlayers providing the highest CE/CCD. Overall, the results demonstrate a manufacturing-relevant approach to engineer SEI nanolayers by salt chemistry, providing pathways to improve reversible lithium metal anodes while reducing reliance on LiTFSI.

anion chemistry↗

Synergistic Coupling Effect of Electronic Conductivity and Interphase Compatibility on High-Voltage Na 3 V 2 (PO 4 ) 2 F 3 Cathodes

Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) has been considered an up-and-coming cathode material candidate for sodium (Na) ion batteries in light of its high specific capacity and working voltage. However, an erratic cathode/electrolyte interface layer is inevitably formed, accompanied by continuous electrolyte decomposition on the NVPF surface, when the voltage exceeds 4.2 V vs Na + /Na. Herein, the interphase features of NVPF are obviously enhanced owing to the ameliorated electronic conductivity obtained by combining it with carbon nanotubes (CNT). The NVPF with 3 wt % CNT (NVPF@3% CNT) reduces the Na + diffusion kinetic energy barrier and electron transport resistance. Furthermore, the conducting network formed by CNT with sturdy structure strength can promptly accommodate the volumetric changes during sequential Na + extraction/insertion and thus effectively improve the long-term cyclic performance of NVPF/hard carbon full cells. The initial discharge capacity approaches 105 mA h g –1 at 0.5C, and it retains 94% capacity retention after 200 cycles at the temperature of –10 °C. The cathode/electrolyte interphase characterization results further demonstrate that the interphase layer on the NVPF@3% CNT cathode is thinner and more compact compared with pristine samples. Here, this research provides a competitive strategy to facilitate the interfacial compatibility between the NVPF and electrolytes and accelerate the commercialization of high-performance Na-ion batteries.

25 ENERGY STORAGE↗

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

Abstract 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 Li 6 PS 5 Cl 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 LiNi 0.6 Mn 0.2 Co 0.2 O 2 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.

Deng, Tao [Department of Chemical and Biomolecular↗

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

Abstract 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 Li 6 PS 5 Cl 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 LiNi 0.6 Mn 0.2 Co 0.2 O 2 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.

Deng, Tao [Department of Chemical and Biomolecular↗

Root Cause Analysis of Degradation in Protonic Ceramic Electrochemical Cell with Interfacial Electrical Sensors Using Data‐Driven Machine Learning

Abstract Protonic ceramic electrochemical cells (PCECs) offer promising paths for energy storage and conversion. Despite considerable achievements made, PCECs still face challenges such as physiochemical compatibility between componenets and suboptimal solid–solid contact at the interfaces between the electrolytes and electrodes. In this study, a novel approach is proposed that combines in situ electrochemical characterization of interfacial electrical sensor embedded PCECs and machine learning to quantify the contributions of different cell components to total degradation, as well as to predict the remaining useful life. The experimental results suggest that the overpotential induced by the oxygen electrode is 48% less than that of oxygen electrode/electrolyte interfacial contact for up to 1171 h. The data‐driven machine learning simulation predicts the RUL of up to 2132 h. The root cause of degradation is overpotential increase induced by oxygen electrode, which accounts for 82.9% of total cell degradation. The success of the failure diagnostic model is demonstrated by its consistency with degradation modes that do not manifest in electrolysis fade during early real operations. This synergistic approach provides valuable insights into practical failure diagnosis of PCECs and has the potential to revolutionize their development by enabling improved performance prediction and material selection for enhanced durability and efficiency.

25 ENERGY STORAGE↗

Molecular Engineering of Biorefining Lignin Waste for Solid-State Electrolyte

Lignin is the second most abundant renewable biopolymer on Earth but also a waste in both the paper industry and lignocellulosic biorefineries. Recently, lignin valorization has been extensively sought after to return economics, enhance carbon efficiency, and improve the bioeconomy, but the commercial value and size compatibility still hinder its applications. In this study, we developed a facile strategy to apply lignin waste into a solid-state electrolyte (SSE), which represents a safe next generation energy storage. Here, lignin was grafted with polyethylene glycol (PEG), an efficient lithium-ion (Li + ) conductive polymer, to enable its ion conduction. The synthesized PEG-g-lignin was mixed with poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP) and PEG-g-lignin-based bis(trifluoromethanesulfonyl)imide (LiTFSI) to prepare a solid polymer electrolyte (SPE), which has an ionic conductivity of 2.5 × 10 –5 S/cm at 25 °C. This result was further enhanced to 6.5 × 10 –5 S/cm by adding an ion-conductive ceramic of Li 6.4 La 3 Ga 0.2 Zr 2 O 12 (LLGZO), which is referred to as composite polymer electrolyte (CPE). These data represent the highest ones among reported polymer-based SSE. A mechanistic study by using 2D HSQC NMR revealed that PEG-g-lignin has increased ether type β–O–4 linkages that can promote the interchain hopping of Li+ between lignin polymer chains, and 31 P NMR revealed that the lignin phenolic end can be associated by Li + . Moreover, the abundant aromatic moieties and methoxyl in PEG-g-lignin also enhanced Li + association and improved its ionic conductivity. The superior ionic conductivity of PEG-g-lignin-based SSE can enable massive applications of this biorefining waste in all-solid-state lithium batteries (ASSLBs), which has potential to promote the energy sector by promoting the bioeconomy and enhancing the renewability and sustainability of future energy storage.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Molecular design for electrolyte solvents enabling energy-dense and long-cycling lithium metal batteries

Electrolyte engineering is critical for developing Li metal batteries. While recent works improved Li metal cyclability, a methodology for rational electrolyte design remains lacking. In this study, we propose a design strategy for electrolytes that enable anode-free Li metal batteries with single-solvent single-salt formations at standard concentrations. Rational incorporation of –CF 2 – units yields fluorinated 1,4-dimethoxylbutane as the electrolyte solvent. Paired with 1 M lithium bis(fluorosulfonyl)imide, this electrolyte possesses unique Li–F binding and high anion/solvent ratio in the solvation sheath, leading to excellent compatibility with both Li metal anodes (Coulombic efficiency ~ 99.52% and fast activation within five cycles) and high-voltage cathodes (~6 V stability). Fifty-μm-thick Li|NMC batteries retain 90% capacity after 420 cycles with an average Coulombic efficiency of 99.98%. Industrial anode-free pouch cells achieve ~325 Wh kg –1 single-cell energy density and 80% capacity retention after 100 cycles. Our design concept for electrolytes provides a promising path to high-energy, long-cycling Li metal batteries.

25 ENERGY STORAGE↗

A Sulfide‐Based Solid Electrolyte With High Humid Air Tolerance for Long Lifespan All‐Solid‐State Sodium Batteries

Abstract Sulfide‐based superionic conductors present great promise to achieve high energy density and safety for all‐solid‐state sodium batteries (ASSSBs). However, the poor electrolyte/electrode interface compatibility and humid air stability seriously hinder their deployment in ASSSBs. Herein, a series of high‐performance Na 3‐□ Sb 1‐4x (SnWCaTi) x S 4 sulfide‐based solid electrolytes (SSEs) are reported by coupling the vacancy effect with configurational entropy, which displays an excellent interface stability against sodium metal and an extraordinary tolerance toward the moist atmosphere, even for water. The optimized electrolyte effectively inhibits the detrimental mixed ion‐electron conducting interphase formation, achieving the ultra‐stable operation of Na–Na symmetric cell up to 1000 h. Furthermore, the Na + diffusion kinetics is obviously enhanced by increasing the Na sites local anisotropy and Na vacancies. Eventually, the assembled TiS 2 //Na 5 Sn ASSSBs deliver a remarkable reversible capacity of 211.6 mAh g −1 at 0.5C with a long‐term cycling performance of 450 cycles at room temperature. More importantly, it achieves a steady running up to 100 cycles at 1C even if this electrolyte is placed in the air with a dew temperature of 13.8 °C for 30 min, the highest values in the state‐of‐the‐art sulfide‐based ASSSBs. The well‐designed SSEs open a new avenue for realizing the advanced and powerful ASSSBs.

Guo, Yayu↗

The Quest for Stable Potassium‐Ion Battery Chemistry

Abstract Potassium‐ion batteries (KIBs) have attracted wide interest for energy storage because of the abundance of the electrode materials involved; however, their electrochemical performances are far behind what can be achieved from lithium‐ion batteries (LIBs) or sodium‐ion batteries (SIBs). Herein, key promising electrode and electrolyte materials for potassium‐ion batteries are identified, the coupled electrochemical reactions in the cell are investigated, and the compatibility between different materials is demonstrated to play the most important role. K 2 Mn[Fe(CN) 6 ] cathode can deliver a high capacity of ≈125 mAh g −1 and exceptional cycling stability over 61 000 cycles (≈9 months) if the side reactions from the anode can be prevented. Graphite is a good anode material but is subjected to degradation in traditional carbonate electrolytes. New concentrated electrolytes are developed and evaluated. A stable KIB system is demonstrated by coupling a stable K 2 Mn[Fe(CN) 6 ] cathode, a prepotassiated graphite anode with a concentrated electrolyte to achieve a high energy density of ≈260 Wh kg −1 (based on the active mass of cathode and anode) and good cycling of over 1000 cycles.

Wu, Xianyong↗

Sulfone-based electrolytes for high energy density lithium-ion batteries

Here, in this work, localized high concentration electrolytes (LHCEs) based on tetramethylene sulfone (TMS) were designed. Similar to LHCEs based on other solvents, TMS-based LHCEs can achieve excellent compatibility with high energy density lithium ion batteries (LIBs) when combined with a proper additive. By comparing LHCEs based on different solvents and additives, it was revealed that the unique solvation structure of LHCEs facilitates the synergetic decomposition of anion, solvent and additive in the solid electrolyte interphase (SEI) formation. Proper combinations of the three constituents of the solvation sheaths in LHCEs can promote the formation of highly effective SEI on graphite negative electrode. The absence of LiPF 6 in LHCEs also suppresses the degradation of positive electrode materials in LIBs. The superior interphasial properties of LHCEs is the key to realizing the long lifespan of high energy density LIBs.

25 ENERGY STORAGE↗

Deep eutectic solvent-based polymer electrolyte for solid-state lithium metal batteries

Poly(ethylene) oxide (PEO)-based electrolytes have been widely studied for solid-state lithium batteries while their ionic conductivity and lithium-ion transference number still need to be further improved. Herein, using the combined experimental and theoretical approach, we demonstrate a novel, solid-state PEO-deep eutectic solvent (DES) electrolyte for the first time. We found that the in situ formation of DES can reduce the crystallinity of PEO matrix and more Li + ions can move freely owing to the weakened coordination between ether oxygens and Li-ions. Besides, we show that more Li + ions can be dissociated from Li salts in PEO-DES electrolyte using the molecular dynamics simulations. Such liquid-free PEO-DES electrolytes showed good ionic conductivity (2.1 × 10 −4 S cm −1 ) which is 160% higher than that of conventional PEO-LiTFSI (8.1 × 10 −5 S cm −1 ) electrolyte at 60 °C. Additionally, the PEO-DES electrolyte showed 136% increase of Li-ion transference number (0.33) compared with ionic liquid-doped PEO-LiTFSI (0.14) at 60 °C. Moreover, the PEO-DES exhibited good compatibility with Li metal and stable Li plating/stripping behavior with little morphology change of Li metal. In conclusion, this research also provides new insights into the enhancement mechanisms of novel polymer electrolytes, improving our fundamental understanding of critical challenges that have impeded the adoption of solid-state lithium metal batteries.

Deep eutectic solvent↗

Conformal hetero-electrolyte interface between soft oxyhalides and garnet enables low-pressure lithium-reservoir-free solid-state batteries

The operation of solid-state batteries with a lithium metal anode and a high voltage cathode requires solid electrolytes (SEs) that are chemically stable with lithium, have a wide electrochemical window, and accommodate volume changes in the electrodes. Unfortunately, no SE has exhibited satisfactory mechanical and electrochemical properties that fit these requirements to date. Dual solid electrolyte systems that use a different SE for the anolyte and catholyte present a viable solution. Here, we focus on oxyhalide SEs that demonstrate superior ionic conductivity and cathode compatibility, where their lithium metal reactivity and poor reduction stability can be resolved using a lithium garnet (Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 , LLZTO) separator. Nonetheless, this imposes a new hetero-electrolyte (H-E) interface at the anolyte|catholyte contact that defines the ion transport across the boundary. We report its promising properties, which are deconvoluted from the electrical measurements of bilayer symmetric cells, for three representative oxyhalide catholytes, LiNbOCl 4 , LiTaOCl 4 , and Li 3 Al 3 O 2 Cl 8 . Pressure-dependent measurements reveal that the relative softness of the oxyhalides (hardness ≤0.4 GPa) enables H-E resistances lower than 150 Ω cm 2 at 2–3 MPa. Mesoscale modelling reveals that the transfer-active contact area of oxyhalides with LLZTO is about 2–3-fold higher than that of argyrodite, Li 6 PS 5 Cl. The low H-E resistance of the LiNbOCl 4 |Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 dual electrolyte enables the cycling of a Li|LiNi 0.82 Mn 0.07 Co 0.11 O 2 full cell with a high discharge capacity (200 mA h g −1 ) at 60 °C and ∼7 MPa. Importantly, we demonstrate a Li-reservoir-free full cell with high Coulombic efficiency (>99.5%) and capacity at 1 MPa using this approach coupled with a garnet-silver interlayer.

Palmer, Max [University of California, Santa Barba↗