High-voltage Batteries Research Articles

Development of GaN-Based, 6.6 kW, 450 V, Bi-Directional On-Board Charger with Integrated 1 kW, 12 V Auxiliary DC-DC Converter with High Power Density

Automotive-grade GaN power switches have recently been made available in the market from a growing number of semiconductor suppliers. The exploitation of this technology enables the development of very efficient power converters operating at much higher switching frequencies with respect to components implemented with silicon power devices. Thus, a new generation of automotive power components with an increased power density is expected to replace silicon-based products in the development of higher-performance electric and hybrid vehicles. 650 V GaN-on-silicon power switches are particularly suitable for the development of 3–7 kW on-board battery chargers (OBCs) for electric cars and motorcycles with a 400 V nominal voltage battery pack. This paper describes the design and implementation of a 6.6 kW OBC for electric vehicles using automotive-grade, 650 V, 25 mΩ, discrete GaN switches. The OBC allows bi-directional power flow, since it is composed of a bridgeless, interleaved, totem-pole PFC AC/DC active front end, followed by a dual active bridge (DAB) DC-DC converter. The OBC can operate from a single-phase 90–264 Vrms AC grid to a 200–450 V high-voltage (HV) battery and also integrates an auxiliary 1 kW DC-DC converter to connect the HV battery to the 12 V battery of the vehicle. The auxiliary DC-DC converter is a center-tapped phase-shifted full-bridge (PSFB) converter with synchronous rectification. At the low-voltage side of the auxiliary converter, 100 V GaN power switches are used. The entire OBC is liquid-cooled. The first prototype of the OBC exhibited a 96% efficiency and 2.2 kW/L power density (including the cooling system) at a 60 °C ambient temperature.

NaSICON Prepared by a Solution-Assisted Reaction Shows Enhanced Stability for High-Voltage Aqueous Redox-Flow Batteries

NaSICON Prepared by a Solution-Assisted Reaction Shows Enhanced Stability for High-Voltage Aqueous Redox-Flow Batteries

A self-assembly capsule-like solvation structure electrolyte for lithium metal batteries

The localized high-concentration electrolyte can be achieved by diluting a high-concentration electrolyte with an anti-solvent, which inherits the original solvation structural characteristics and reduces harmful interfacial reactions, resulting in an electrolyte with unique functions suitable for lithium metal batteries. Here, we design a localized high-concentration electrolyte with a capsule-like solvation structure and non-flammable properties to obtain stable-cycle and safe lithium metal batteries. The weak coordination and dipole-dipole interactions of fluorinated ether molecules promote the self-assembly of capsule-like solvated sheaths, encapsulating cations/anions and polar solvent molecules within the solvation sheath, which improves the oxidative stability of the electrolyte system and promotes the reduction of anions. A high-quality solid electrolyte layer was derived at the electrode interfaces, leading to rapid Li+ transport and dendrite-free lithium deposition. Consequently, a Coulombic efficiency of 99.7% is achieved, and the assembled Li||NCM811 battery exhibits a long cycle life of more than 400 cycles at 0.5C with a capacity retention of 83%. This work provides a promising approach for developing non-flammable electrolytes suitable for high-voltage lithium metal batteries.

A PVDF-HFP/YSZ nanofiber composite solid-state electrolyte by in-situ polymerization of 1,3-dioxolane for 4.5 V high-voltage NCM811 battery

Solid lithium metal batteries with solid polymer electrolytes have advantages in terms of high energy density and safety. However, their application is still hindered by unstable solid electrolyte interfaces (SEI and CEI) and uncontrolled dendrite growth. Here, a composite skeleton loaded with dielectric filler yttrium stabilized zirconia nanoparticles (YSZ) on the surface of PVDF-HFP nanofiber filaments is designed, and a novel composite solid electrolyte (CSE) is prepared by in-situ polymerization of DOL (1,3-dioxolane) on this framework to achieve safe and stable high-voltage lithium metal battery (LMB). The dual stable electrode interfaces (CEI and SEI) constructed by in-situ can effectively suppress the generation of lithium dendrites and suppress the degradation of the high-voltage NCM811 positive electrode structure and the generation of cracks in NCM811 particles, endowing the battery with extraordinary performance. The as-obtained CSE exhibits high ionic conductivity of 1.01 × 10−3 S cm−1 at 30 °C, the enlarged electrochemical window of 6.0 V, and the Li+ transference number is 0.72. The assembled Li|NCM811 battery is capable of stable cycling for 400 cycles at a cut-off voltage of 4.5 V and current density of 1C, with a capacity decay of only 0.074 % per cycle. .

Numerical Study of an Automotive Crash Box in Carbon Fiber Reinforced Polymer Material Using Chang Failure Criteria

This paper discusses novel numerical techniques for studying the damage to automotive safety components in carbon fiber reinforced polymer (CFRP) deployed in the automotive industry to protect passengers, high voltage batteries and powertrains from rear impacts. The idea proposed in the manuscript is to use Newmark’s methodology with the FEM for the numerical description of the explicit dynamic model of the components facing the standard impactor, following the Euro NCAP protocol. Using an explicit dynamic Radioss rear crash box, we have successfully demonstrated normal behavior for CFRP materials, where the value of kinetic energy is close to the theoretical value. Moreover, the simulation provides a behavior consistent with previous successful studies because the maximum dynamic time is the same as the total damage (0.10 ms).

Performance and Efficiency Evaluation of a Secondary Loop Integrated Thermal Management System with a Multi-Port Valve for Electric Vehicles

Recently, battery electric vehicles (BEVs) have faced various technical challenges, such as reduced driving range due to ambient temperature, slow charging speeds, fire risks, and environmental regulations. This numerical study proposes an integrated thermal management system (ITMS) utilizing R290 refrigerant and a 14-way valve to address these issues, proactively meeting future environmental regulations, simplifying the system, and improving efficiency. The performance evaluation was conducted under high-load operating conditions, including driving and fast charging in various environmental conditions of 35 °C and −10 °C. As a result, the driving efficiency was 4.82 km/kWh in high-temperature conditions (35 °C) and 4.69 km/kWh in low-temperature conditions (−10 °C), which demonstrated higher efficiency than the Octovalve-ITMS applied to the Tesla Model Y. Furthermore, in fast charging tests, the high voltage battery was charged from a 10% to a 90% state of charge in 26 min at 35 °C and in 31 min at −10 °C, outperforming the Octovalve-ITMS-equipped Tesla Model Y’s fast charging time of 27 min under moderate ambient conditions. This result highlights the superior fast-charging performance of the 14-way valve-based ITMS, even under high cooling load conditions.

Ionic Liquid Additive Mitigating Lithium Loss and Aluminum Corrosion for High-Voltage Anode-Free Lithium Metal Batteries.

Concentrated electrolytes based on lithium bis(fluorosulfonyl)imide (LiFSI) have been proposed as an effective Li-compatible electrolyte for anode-free lithium metal batteries (AFLMBs). However, these electrolytes suffer from severe aluminum corrosion at an elevated potential. To address this issue, we propose a binary ionic liquid (IL) electrolyte additive comprising the 1-methyl-1-butyl pyrrolidinium cation (Pyr14+), difluoro(oxalate)borate anion (DFOB-), and difluorophosphate (PO2F2-) anion to mitigate the Li inventory loss and Al corrosion in 4 M LiFSI/DME electrolyte simultaneously. On the anode side, the IL additive facilitates the formation of a robust Li3N- and LiF-rich solid electrolyte interphase, promoting highly reversible Li plating/stripping and uniform Li deposition. Additionally, the ILs alter the Li+ solvation structure, leading to enhanced tLi+ and rapid Li+ desolvation kinetics. Concurrently, on the cathode side, the ILs aid in the generation of dense LiF- and AlF-rich passivation films against Al corrosion. By using the IL-added electrolyte, the Cu||LiMn0.7Fe0.3PO4 cell operates stably at 4.5 V, and the Cu||NCM613 cell with a high loading of 4.0 mA h cm-2 sustains 142 cycles until 80% capacity retention. This research contributes to a deeper understanding of the IL additive mechanism at the electrode-electrolyte interfaces and offers a straightforward approach to designing practical high-voltage AFLMB electrolytes.

Solvent Polarity-Induced Regulation of Cation Solvation Sheaths for High-Voltage Zinc-Based Batteries with a 1.94 V Discharge Platform.

To address the challenge of low discharge platforms (<1.5 V) in aqueous zinc-based batteries, highly concentrated salts have been explored due to their wide electrochemical window (~3 V). However, these electrolytes mainly prevent hydrogen evolution and dendrite growth at the anode without significantly enhancing voltage performance. Herein we introduce an approach by adjusting solvent polarity to regulate cation solvation sheaths in hybrid electrolytes, reducing Zn/Zn2+ oxidation potential and water activity. Through strong cation-water coordination and hydrogen bonding between dimethylsulfoxide and water, the designed electrolyte, at a low concentration, achieves a broader electrochemical window (4 V) than conventional concentrated electrolytes. Using this electrolyte, a Zn/Zn battery showed an impressive cycle life of 4340 cycles, while a Zn/lithium manganate battery delivered a high discharge platform of over 1.9 V with exceptional cycling stability. A Zn-based micro-battery with a polyvinyl alcohol-based hybrid electrolyte also achieved a record-high discharge platform of 1.94 V. This work presents a promising strategy for developing low-concentration electrolytes for high-performance sustainable energy storage.

Regulating Non-Equilibrium Solvation Structure in Locally Concentrated Ionic Liquid Electrolytes for Wide-Temperature and High-Voltage Lithium Metal Batteries.

The development of high-voltage lithium metal batteries (LMBs) encounters significant challenges due to aggressive electrode chemistry. Recently, locally concentrated ionic liquid electrolytes (LCILEs) have garnered attention for their exceptional stability with both Li anodes and high-voltage cathodes. However, there remains a limited understanding of how diluents in LCILEs affect the thermodynamic stability of the solvation structure and transportation dynamics of Li+ ions. Herein, we propose a wide-temperature LCILEs with 1,3-dichloropropane (DCP13) diluent to construct a non-equilibrium solvation structure under external electric field, wherein the DCP13 diluent enters the Li+ ion solvation sheath to enhance Li+ ion transport and suppress oxidative side reactions at high-nickel cathode (LiNi0.9Co0.05Mn0.05O2, NCM90). Consequently, a Li/NCM90 cell utilizing this LCILE achieves a high capacity retention of 94 % after 240 cycles at 4.3 V, also operates stably at high cut-off voltages from 4.4 V to 4.6 V and over a wide temperature range from -20 °C to 60 °C. Additionally, an Ah-level pouch cell with this LCILE simultaneously achieves high-energy-density and stable cycling, manifesting the practical feasibility. This work redefines the role of diluents in LCILEs, providing inspiration for electrolyte design in developing high-energy-density batteries.

Engineering π-Electron Bridge Enables Low-Potential 2D Redox Polymer Anodes for High-Voltage Aqueous All-Organic Batteries.

Aqueous all-organic batteries (AAOBs) have emerged as a hot topic but their development was plagued by limited choices of anode materials, generally facing an intractable trade-off between low potential and high stability. Here, we propose a novel π-electron bridge engineering strategy to explore a class of 2D dioxin-bridged redox covalent organic polymer (RCOP) as trade-off-breaking anodes for high-voltage AAOBs. By establishing a tunable RCOP platform, we perform theoretical study to scrutinize how bridge units between active sites affect the electrode potential and redox activity for the first time. We discover that compared to common pyrazine bridge, the weakened conjugation and strong electron donor character of the proposed dioxin bridge can induce elevated LUMO level and enriched π-electron populations in active sites, heralding a low electrode potential and enhanced redox activity. Besides, the nonaromaticity-induced molecular flexibility of dioxin bridge mitigates intermolecular stacking for sufficient active sites exposure. To experimentally corroborate this, a new dioxin-bridged 2D RCOP (D-HATN) and its pyrazine-bridged analogue (P-HATN) are synthesized for proof-of-concept demonstration. D-HATN displays excellent compatibility with Na+/Zn2+/NH4 +/H3O+ and obviously lower redox potentials in various dilute electrolytes compared to P-HATN and most reported organic anodes, while featuring rapid Grotthuss-type proton conduction and unprecedented durability in acid - 91.8 % capacity retention after 20000 cycles. Thus, the D-HATN-involved all-organic proton battery delivers an average output voltage of 0.75 V, which can be further elevated to 1.63 V with alkaline-acidic hybrid electrolyte design, affording markedly-increased specific energy.

Iodine/Chlorine Multi-Electron Conversion Realizes High Energy Density Zinc-Iodine Batteries.

Aqueous zinc-iodine (Zn-I2) batteries are promising energy storage devices; however, the conventional single-electron reaction potential and energy density of iodine cathode are inadequate for practical applications. Activation of high-valence iodine cathode reactions has evoked a compelling direction to developing high-voltage zinc-iodine batteries. Herein, ethylene glycol (EG) is proposed as a co-solvent in a water-in-deep eutectic solvent (WiDES) electrolyte, enabling significant utilization of two-electron-transfer I+/I0/I- reactions and facilitating an additional reversibility of Cl0/Cl- redox reaction. Spectroscopic characterizations and calculations analyses reveal that EG integrates into the Zn2+ solvation structure as a hydrogen-bond donor, competitively binding O atoms in H2O, which triggers a transition from water-rich to water-poor clusters of Zn2+, effectively disrupting the H2O hydrogen-bond network. Consequently, the aqueous Zn-I2 cell achieves an exceptional capacity of 987 mAh gI2 -1 with an energy density of 1278Wh kgI2 -1, marking an enhancement of ≈300 mAh g-1 compared to electrolyte devoid of EG, and enhancing the Coulombic efficiency (CE) from 68.2% to 98.7%. Moreover, the pouch cell exhibits 3.72 mAh cm-2 capacity with an energy density of 4.52 mWh cm-2, exhibiting robust cycling stability. Overall, this work contributes to the further development of high-valence and high-capacity aqueous Zn-I2 batteries.

Modulating Interfacial Solvation via Ion Dipole Interactions for Low-Temperature and High-Voltage Lithium Batteries.

Extending the stability of ether solvents is pivotal for developing low-temperature and high-voltage lithium batteries. Herein, we elucidate the oxidation behavior of tetrahydrofuran with ternary BF4-, PF6- and difluoro(oxalato)borate anions and the evolution of interfacial solvation environment. Combined in-situ analyses and computations illustrate that the ion dipole interactions and the subsequent formation of ether-Li+-anion complexes in electrolyte rearrange the oxidation order of solvated species, which enhances the electrochemical stability of ether solvent. Furthermore, preferential absorption of anions on the surface of high-voltage cathode favors the formation of a solvent-deficient electric double layer and an anti-oxidation cathode electrolyte interphase, inhibiting the decomposition of tetrahydrofuran. Remarkably, the formulated electrolyte based on ternary anion and tetrahydrofuran solvent endows the LiNi0.8Co0.1Mn0.1O2 cathode with considerable rate capability of 5.0 C and high capacity retention of 93.12% after 200 cycles. At a charging voltage of 4.5 V, the Li||LiNi0.8Co0.1Mn0.1O2 cells deliver Coulombic efficiency above 99% at both 25 and -30 °C.

Anion Modulation: Enabling Highly Conductive Stable Polymer Electrolytes for Solid-State Li-Metal Batteries.

Solid polymer electrolytes (SPEs) are promising ionic conductors for developing high-specific-energy solid-state lithium metal batteries. However, developing SPEs with both high ionic conductivity and interfacial compatibility remains a challenge. Here, we propose a design concept of an anion-modulated polymer electrolyte (termed AMPE) for high-voltage Li metal batteries. Specifically, we design the AMPE by incorporating high-voltage-resistant and high charge density units with an anion receptor unit. The high-voltage-resistant and high charge density segments contribute to achieving a decent voltage tolerance of the polymer chains and ensure sufficient carrier ions. The anion receptor, represented by a boron-containing molecule, promotes the generation of free Li+ by dissociating anion-cation pairs. More importantly, the strong interaction between the electron-deficient B and the TFSI- in the matrix promotes the anion reduction to form a stable anion-derived mosaic-like solid electrolyte interphase on the Li-metal anode. As a result, the AMPE exhibits a high Li+ conductivity of 3.80×10-4 S cm-1 and effectively suppresses lithium dendrites, enabling an all-solid-state Li|AMPE|LiCoO2 cell to achieve a cycle life of 700 cycles at an operating voltage of 4.40 V. This design concept would inspire efforts to develop high-performance SPEs for high-specific-energy solid-state lithium metal batteries.

Multifunctional carbonyl-rich compounds for constructing “corrosion-resistant electrodes and electrolyte interface” in high-voltage sodium-metal batteries

In recent years, there has been notable advancement in the development of high-performance materials for sodium-ion batteries, particularly in layered oxide cathodes. However, research on enhancing the interface between electrolytes and cathodes remains nascent. One promising approach involves the addition of electrolyte additives, recognized for their cost-effectiveness and efficiency in bolstering the electrode/electrolyte interface to enhance material stability during high-voltage cycling. In this work, we investigate the use of glutaric anhydride (GA) as an electrolyte additive to improve the cycling stability of NaNi1/3F1/3M1/3O2/Na (NFM/Na) high-voltage sodium-metal batteries. Batteries using GA-containing electrolytes demonstrate impressive capacity retention: 80.51 % after 200 cycles at 4.0 V and 76.01 % after 150 cycles at 4.1 V. The research delves into the mechanistic insights behind GA’s effectiveness in enhancing cyclic stability. Theoretical calculations reveal that GA plays a crucial role in modifying the structure of the first solvation shells, promoting the formation of an elastic cathode-electrolyte interface (CEI) film enriched with OCO groups. This uniform and stable CEI film effectively preserves the material’s crystal structure and mitigates the dissolution of transition metals, thereby prolonging battery lifespan under demanding extremely cycling conditions.

ETPTA polymer network confined amide-based eutectic electrolyte for safe and long- life lithium metal battery

Serious safety issues and uncontrollable lithium dendrites hinder the commercial application of high-voltage lithium metal batteries (LMBs) that employ carbonate-based electrolytes. Herein, we propose a eutectogel electrolyte, an amide-based eutectic electrolyte consisting of lithium bis (trifluoromethyl sulfonyl) imide (LiTFSI) and N-methyl-2,2,2-trifluoroacetamide (3F-NMA) confined by trimethylolpropane ethoxylate triacrylate (ETPTA) polymer network. Compared with the carbonate-based electrolyte, the non-flammable eutectogel electrolyte facilitates the formation of LiF/LixN-rich solid electrolyte interfaces, therefore expands the electrochemical window, enhances the interfacial compatibility, and improves the cycling stability of LMB. Besides, it shows a high lithium-ion transference number of 0.63 and a stable long-term lithium stripping/plating (>2300 h) in a Li||Li symmetric cell, at a current density of 0.2 mA cm−2. Additionally, the Li||LiFePO4 full cell with eutectogel electrolyte exhibits a commendable cycling stability, achieving a capacity retention of 77.4 % after 1000 cycles at 5 C (30 °C) and maintaining 82 % capacity following 400 cycles at 1 C (60 °C). When used as the electrolyte in Li||LiCoO2 full cell, it renders the battery appealing performance including a notable initial discharge capacity of 170.3 mAh g−1 and a retained capacity of 86.3 % after 300 cycles, at a high charge voltage of 4.45 V. This research may provide insight into the design of eutectogel electrolytes for high-performance lithium metal batteries.

Ultrastrong nonflammable in-situ polymer electrolyte with enhanced interface stability boosting high-voltage Li metal batteries under harsh conditions

In-situ polymer electrolytes prepared by Li salt-initiated polymerization are promising electrolytes for solid-state Li metal batteries owing to their enhanced interface contact and facile and green preparation process. However, conventional in-situ polymer electrolytes suffer from poor interface stability, low mechanical strength, low oxidation stability, and certain flammability. Herein, a silsesquioxane (POSS)-nanocage-crosslinked in-situ polymer electrolyte (POSS-DOL@PI-F) regulated by fluorinated plasticizer and enhanced by polyimide skeleton is fabricated by Li salt initiated in-situ polymerization. Polyimide skeleton and POSS-nanocage-crosslinked network significantly enhance the tensile strength (22.8 MPa) and thermal stability (200 °C) of POSS-DOL@PI-F. Fluorinated plasticizer improves ionic conductivity (6.83 × 10−4 S cm−1), flame retardance, and oxidation stability (5.0 V) of POSS-DOL@PI-F. The fluorinated plasticizer of POSS-DOL@PI-F constructs robust LiF-rich solid electrolyte interphases and cathode electrolyte interphases, thereby dramatically enhancing the interface stability of Li metal anodes and LiNi0.8Mn0.1Co0.1O2 (NCM811) cathodes. POSS-DOL@PI-F enables stable, long-term (1200 h), and dendrite-free cycle of Li||Li cells. POSS-DOL@PI-F significantly boosts the performance of Li||NCM811 cells, which display superior cycle stability under harsh conditions of high voltage (4.5 V), high temperature (60 °C), low temperature (−20 °C), and high areal capacity. This work provides a rational design strategy for safe and efficient polymer electrolytes.

MOF-Derived Nitrogen-Rich Hollow Nanocages as a Sulfur Carrier for High-Voltage Aluminum Sulfur Batteries.

Aluminum-sulfur batteries (ASBs) are emerging as promising energy storage systems due to their safety, low cost, and high theoretical capacity. However, it remains a challenge to overcome voltage hysteresis and short cycle life in the sulfur/Al2S3 conversion reaction, which hinders the development of ASBs. Here, we studied a high-voltage ASB system based on sulfur oxidation in an AlCl3/urea electrolyte. Nitrogen-doped hollow nanocages (HNCs) synthesized from MOF precursors were rationally designed as sulfur/carbon composite electrodes (S@HNC), and the impact of the nitrogen species on the electrochemical performance of sulfur electrodes was systematically investigated. The S@HNC-900 achieved efficient conversion at 1.9 V, delivering a stable capacity of 197.3 mA h g-1 and a Coulombic efficiency of 93.28% after 100 cycles. Furthermore, the S@HNC-900 electrode exhibited exceptional rate capacity and 800th long-term cycling stability, retaining a capacity of 87.1 mA h g-1 at 500 mA g-1. Ex situ XPS and XRD characterizations elucidated the redox mechanism, revealing a four-electron transfer process (S/AlSCl7) at the S@HNC-900 electrode. Density functional theory calculations demonstrated that pyridinic nitrogen-enriched HNC-900 significantly enhanced the sulfur conversion reaction and facilitated the adsorption of sulfur intermediates (SCl3+) on the carbon interface. This work provides critical insights into the high-voltage sulfur redox mechanism and establishes a foundation for the rational design of carbon-based electrocatalysts for the enhancement of ASB performance.

Unveiling the Role of Filler Characteristics in Enhancing the High-Voltage Performance of Succinonitrile-Based Solid-State Lithium-Metal Batteries.

For exploiting high-energy lithium-metal batteries, it is of utmost importance to develop electrolytes that possess exceptional ionic conductivity and an extensive electrochemical stability range. In this study, 3D PAN nanofibers and polymer electrolytes incorporating various inorganic fillers with different Lewis acid-base properties were fabricated. PAN@Al-SSE exhibits exceptional ionic conductivity (0.48 mS·cm-2 at room temperature), a high Li+ transference number (0.41), and a wide electrochemical window (5.26 V). The device is able to operate stably in Li symmetric cells for more than 1000 h under a potential of 0.03 V under a current density of 0.2 mA·cm-2. Besides, the groundbreaking technology equips high-voltage Li-LiCoO2 solid-state batteries with exceptional cycling performance (91.3% and 82.1% retention after 100 cycles at 0.2 and 1 C, respectively) at room temperature. Mechanistic studies indicate that the Lewis acid-base properties of surface fillers are instrumental and crucial to form a stable solid-electrolyte interphase layer. γ-Al2O3, in particular, with more Lewis acid sites, ensures the dissociation of LiTFSI and induces the excessive decomposition and polymerization of succinonitrile. There exists an equilibrium effect between dissociation and polymerization in a succinonitrile-based solid electrolyte, which plays a critical role in improving the manifestation of succinonitrile-based solid-state lithium cells, especially under high-voltage conditions.

Helmholtz Plane Regulation Empowers PF6 - Permselectivity Towards High Coulombic Efficiency Dual Ion Battery of 5.5 V.

High-voltage dual ion battery (DIB) is promising for stationary energy storage applications owing to its cost-effectiveness, which has been a hot topic of research in rechargeable battery fields. However, it still suffers from rapid battery failure caused by the severe solvent co-intercalation and electrolyte oxidation. To address these bottlenecks, herein a functional electrolyte additive hexafluoroglutaric anhydride (HFGA) is presented based on a Helmholtz plane regulation strategy. It is demonstrated that the HFGA can precisely enter into the Helmholtz plane and positively regulate anion solvation behaviors near the graphite electrode surface owing to its considerable H-F affinity with ethyl methyl carbonate (EMC), thus alleviating EMC-related co-intercalation and oxidation decomposition during DIB charging. Meanwhile, HFGA can copolymerize with the presence of PF5 at the Helmholtz plane to participate in forming a CF2-rich CEI layer with excellent PF6 - permselectivity, conducive to achieving PF6 - de-solvation and simultaneously suppressing electrolyte oxidation decomposition. By virtue of such beneficial effects, the graphite cathode enables a 5.5 V DIB with a prominent capacity retention of 92 % and a high average Coulombic efficiency exceeding 99 % within 2000 cycles at 5 C, demonstrating significantly enhanced electrochemical reversibility. The Helmholtz plane regulation strategy marks a milestone in advancing DIB technologies.

Multisite Crosslinked Poly(ether-urethane)-Based Polymer Electrolytes for High-Voltage Solid-State Lithium Metal Batteries.

Utilizing solid-state polymer electrolytes (SPEs) in high-voltage Li-metal batteries is a promising strategy for achieving high energy density and safety. However, the SPEs face the challenges such as undesirable mechanical strength, low ionic conductivity and incompatible high-voltage interface. Here, a novel crosslinked poly(ether-urethane)-based SPE with a molecular cross-linked structure is fabricated to create high-throughput Li+ transport pathway. The amino-modified Zr-porphyrin-based metal-organic frameworks (ZrMOF) are introduced as multisite cross-linking nodes and polymer chain extenders. The abundant ether/ketonic-oxygen and Lewis acid sites in the SPE achieve high Li+ conductivity (5.7 × 10-4 S cm-1 at 30°C) and Li+ transference number (0.84). The interpenetrating cross-linked structure of SPE with robust mechanical strength results in a record cycle life of 8000h in Li||Li symmetric cell. The high structural stability of ZrMOF and abundant electron-withdrawing urethane/ureido groups in the SPE with high oxidation potential (5.1V) enables a discharge capacity of 182 mAh g-1 at 0.3 C over 500 cycles in a LiNi0.8Co0.1Mn0.1O2||Li cell. Remarkably, a high energy density of 446Wh kg-1 in a 1.5-Ah pouch cell is obtained with high loading cathode (≈4 mAh cm-2), demonstrating a great prospect of the current SPE for practical application in solid-state, high-voltage Li-metal batteries.