Liquid Batteries Research Articles

High-Strength Silicon Anodes with High Tap Density via Compression Carbonization for Liquid and All-Solid-State Lithium-Ion Batteries.

Despite the advantages of nanostructure design with a balance of capacity and cycle life, the low tap density (<1 g cm-3) and high swelling properties make nanostructured silicon far from practical in applications. Here, we design a free-standing silicon graphite composite integrated anode through facile one-pot sintering with pitch under pressure. The thermomechanical effect during compression carbonization enables the integrated electrode to achieve a high tap density of 1.51 g cm-3, >2 times that of typical free-standing electrodes. In situ expansion measurements demonstrate that the longitudinal expansion of integrated electrodes is <20% of that of conventional electrodes. A rational conductive framework enables integrated electrodes to exhibit remarkable cycling stability in both liquid lithium-ion batteries (77.6% capacity retention after 500 cycles) and all-solid-state lithium-ion batteries (98.5% capacity retention after 1000 cycles). In particular, integrated electrodes remain stable even with a high areal capacity of 12.6 mAh cm-2.

Numerical investigation and optimization of liquid battery thermal management system considering nanofluids, structural, and flow modifications under high discharge cycles

The thermal management of electric vehicle (EV) batteries continues to be a pressing challenge preventing wider EV adoption due to performance and safety concerns. Liquid battery thermal management systems (BTMSs) are the most commercially viable thermal management option due to their high heat transfer efficiency and compact design, despite these promising features, the current liquid BTMS designs suffer from high energy consumption and temperature gradients which severely affect the BTMS performance. To address these issues, this study numerically investigated the influence of various liquid BTMS design parameters for a 12 cylindrical lithium-ion battery module. The study evaluated 21 different BTMS configurations based on the maximum battery temperature, temperature difference, pressure drop, and energy consumption. Based on the selected evaluation criteria, The optimized liquid BTMS design (one cooling block, bidirectional flow, 0.0015 kg/s mass flow rate, 4 mm cell spacing, continuous operation strategy with hybrid CuO-MgO-TiO2 water 0.5 % concentration nanofluid) maintained the maximum temperature and temperature difference at 31.34 and 5.3 °C respectively, a 4.3 % and 21.1 % improvement compared to the base design, with a total pressure drop of 12.84 Pa when operated under 35 °C ambient temperature and 3C discharge rate. Proving the effectiveness of the proposed liquid BTMS design.

Pre-coordination anchoring strategy for modulating the coordination structure of iron single atoms and ORR performance

Among numerous potential alternatives to platinum-based catalysts, single-atom Fe catalysts with a symmetrical planar tetra-coordinated structure anchored by nitrogen (FeN4) have shown the most promising ORR activity. However, extensive research has shown that the highly symmetric planar structure of the FeN4 site leads to symmetric electron distribution, which is detrimental to the adsorption and activation of oxygen intermediates, thereby hindering further improvement in ORR kinetics and performance. Herein, using the pre-coordination anchoring strategy, we prepared high-loading S, N-coordinated single-atom catalysts with an FeSN3 structure (referred to as Fe SACs/SNC). Due to the optimized charge distribution of Fe active centers, Fe SACs/SNC exhibited outstanding alkaline ORR performance. In addition, Fe SACs/SNC assembled as air cathodes in liquid and solid zinc-air batteries showed stable cycling for over 900 h (2700 cycles) and 190 h (1140 cycles), respectively, while solid-state batteries also demonstrated good flexibility.

One-stone-for-two-birds strategy to construct robust 2D conjugated metal-organic framework-based quasi-solid-state lithium-organic batteries

Quasi-solid-state lithium batteries (QSSLBs) are emerging as attractive candidates for overcoming the disadvantages of liquid and solid batteries. However, they face challenges in terms of enhancing the poor interfacial stability and promoting selective Li+ conduction. Herein, one-stone-for-two-birds strategy is proposed that involves using a two-directional conjugated metal organic framework (2D-cMOF, Fe-TABQ) as both the cathode material and a polymer–electrolyte filler to construct high-performance quasi-solid-state lithium–organic batteries (QSSLOBs). Additionally, Fe-TABQ promotes the cleavage of C–F bonds, thus facilitating the formation of a LiF-rich solid electrolyte interface (SEI). Therefore, the composite polymer electrolyte presents a high Li+ transference number of 0.93 and a high ionic conductivity of 6.22 × 10−3 mS cm−1. Meanwhile, Li/Li symmetric cells deliver stable cyclability for 1,500 h at 25 ℃ and a current density of 0.05 mA cm−2. Even the assembled QSSLOBs exhibit a high initial discharge specific capacity of 248.39 mAh/g at 25 ℃, and 50 mA g−1 and long cycle stability with 70 % capacity retention after 200 cycles at 25 ℃ and 1,000 mA g−1. The present findings reveal the multiple functional potentials of 2D-cMOFs in constructing robust QSSLOBs.

Engineering the Local Atomic Environments of Te-Modulated Fe Single-Atom Catalysts for High-Efficiency O2 Reduction.

Atomically dispersed metal-nitrogen-carbon materials (AD-MNCs) are considered the most promising non-precious catalysts for the oxygen reduction reaction (ORR), but it remains a major challenge for simultaneously achieving high intrinsic activity, fast mass transport, and effective utilization of the active sites within a single catalyst. Here, an AD-MNCs consisting of defect-rich Fe-N3 sites dispersed with axially coordinated Te atoms on porous carbon frameworks (Fe1Te1-900) is designed. The local charge densities and energy band structures of the neighboring Fe and Te atoms in FeN3-Te are rearranged to facilitate the catalytic conversion of the O-intermediates. Meanwhile, the negative shift of the d-band center in FeN3-Te reduces the energy barrier limit for effective desorption of the final OH* intermediate. In the electrochemical evaluation, Fe1Te1-900 presents a more positive onset potential and half-wave potentials of 1.03 and 0.89V versus the reversible hydrogen electrode, respectively. Furthermore, the liquid zinc-air batteries assembled with Fe1Te1-900 exhibited excellent performances compared to commercial Pt/C. This work opens up new ideas for the development of high-performance ORR electrocatalysts for applications in various energy conversion and storage technologies.

Pyrite‐Based Solid‐State Batteries: Progresses, Challenges, and Perspectives

AbstractPyrite (FeS2), as a transition metal sulfide, has a promise application in the field of secondary batteries due to its abundant reserves, high theoretical capacity, safety, and non‐toxicity. However, serious volume expansion and shuttle effect of FeS2 in liquid secondary batteries limit its further development. Solid‐state batteries offer effective solutions to these challenges. In this review, the synthesis methods of FeS2 and recent progress in FeS2‐based solid‐state lithium/sodium batteries are presented, and the effects of FeS2 size and morphology, solid electrolyte type, and battery structure design on the electrochemical performance of solid‐state batteries are discussed. By analyzing and summarizing the problems in applying FeS2 in solid‐state batteries, the remaining challenges in this field are discussed and future directions are proposed. This review aims to guide research on high‐performance solid‐state batteries based on FeS2 and promote further development of FeS2 in electrochemical energy storage.

Review of Progress in the Application of Polytetrafluoroethylene-Based Battery Separators.

Batteries have broad application prospects in the aerospace, military, automotive, and medical fields. The performance of the battery separator, a key component of rechargeable batteries, is inextricably linked to the quality of the batteries. The polytetrafluoroethylene (PTFE)-based membrane, in addition to PTFE's intrinsic properties of corrosion resistance and high temperature resistance, also possesses characteristics such as high porosity and high strength, making it an ideal substrate for the separator in current high-performance batteries, such as fuel cells (FC), all-vanadium redox liquid current batteries (VRBs), solid-state batteries (SSBs), and lithium-ion batteries (LIBs). This paper introduces the PTFE membrane's main preparation methods and application fields and outlines its advantages as a battery separator. It then comprehensively describes the status of PTFE-based battery separator applications, sums up the advantages and development prospects of PTFE-based battery separators, and looks forward to the important role and challenges PTFE-based battery separators will play in the future of rechargeable batteries and even in new energy equipment with even more harsh and complex electrolytes. In the future, PTFE-based battery separators will be used in rechargeable batteries and even in new energy devices with more severe and complex electrolytes, which will play an important role and challenge in providing a reference for the research on PTFE-based battery separators.

Research Progress on Solid-state Electrolyte Interface Problems in Lithium-ion Batteries

Nowadays, compared with traditional liquid batteries, solid-state batteries have the superiorities of higher energy density, power density and safety due to their solid electrolytes. However, a series of interfacial problems at solid-solid interface have always hindered the further development of solid-state batteries. Based on these problems, this paper firstly introduces the types of solid-state batteries and interface, secondly describes the mechanical failure principles of cathode interface and anode interface, and finally elaborates the corresponding modification strategies for cathode interface and anode interface. By adopting various improved measures for these interfacial problems, the progress of wider commercialization of solid-state batteries can be facilitated.

An Efficient Cathode Catalyst for Rechargeable Zinc-air Batteries based on the Derivatives of MXene@ZIFs.

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are crucial processes at the cathode of zinc-air batteries. Developing highly efficient and durable electrocatalysts at the air cathode is significant for the practical application of rechargeable zinc-air batteries. Herein, N-doped layered MX containing Co2P/Ni2P nanoparticles is synthesized by growing CoNi-ZIF on the surface and interlayers of the two-dimensional material MXene (Ti2C3) followed by phosphating calcination. The growth of CoNi-ZIF on the surface of MXene results in the attenuation of high-temperature structural damage of MXene, which in turn leads to the formation of Co2P/Ni2P@MX with a hierarchical configuration, higher electron conductivity, and abundant active sites. The optimized Co2P/Ni2P@MX achieves a half-wave potential of 0.85 V for the ORR and an overpotential of 345 mV for the OER. In addition, DFT calculations were adopted to investigate the mechanism at the atomic and molecular levels. The liquid zinc-air battery with Co2P/Ni2P@MX as the cathode exhibits a specific capacity of 783.7 mAh g-1 and exceeds 280 h (840 cycles) cycle stability, superior to zinc-air batteries constructed by the cathode of commercial Pt/C+RuO2 and other previous works. Furthermore, a solid-state battery synthesized with Co2P/Ni2P@MX as the cathode exhibits stable cycle performance (154 h/462 cycles).

Magnesium and Aluminum in Contact with Liquid Battery Electrolytes: Ion Transport through Interphases and in the Bulk

Magnesium and Aluminum in Contact with Liquid Battery Electrolytes: Ion Transport through Interphases and in the Bulk

Effect of pH, acid catalyst, and aging time on pore characteristics of dried silica xerogel

ABSTRACT This study investigates the impact of pH and ageing time on silica xerogel pore characteristics prepared via the sol-gel method. Using tetraethyl orthosilicate (TEOS) and HCl as a precursor and acid catalyst, respectively, tailored pore size distributions in the meso- and macroporous range were achieved. Field emission scanning electron microscopy (FESEM) revealed interconnected porous structures, with pore size increasing linearly with ageing time. pH variation yielded average pore sizes ranging from ~ 31 nm (mesoporous) to ~ 59 nm (macroporous). Higher acid catalyst concentration accelerated gelation, resulting in smaller pores. Elemental analysis confirmed silicon and oxygen as primary constituents, while X-ray diffraction (XRD) confirmed amorphous nature. Sol-gel synthesis provides versatile control over microstructure and properties, enabling customisation for applications such as liquid filters, batteries, sensors, and bio-scaffolds. It offers a cost-effective, direct synthesis of high-purity multi-component materials, emphasising its potential for functional material development.

Enhanced Zinc-air battery performance and local electrochemical evaluation of atomically dispersed Co and Ni in S, N-codoped carbon nanofibers via scanning electrochemical microscopy

This study reports the successful synthesis of a novel electrocatalyst for oxygen reduction reactions (ORR), comprising S,N dual-doped carbon nanofibers with atomically dispersed Co/Ni species (denoted as Co,Ni-SAs/S,N-CNFs), leveraging electrostatic spinning to achieve a unique spatial architecture that maximizes both active site density and mass transport efficiency. Density functional theory (DFT) analysis identified the initial proton-electron transfer to adsorbed O2 as the rate-limiting step, with CoN3S1-NiN3S1 emerging as the pivotal active site structure catalyzing this critical reaction. The fabricated Co,Ni-SAs/S,N-CNFs electrocatalyst exhibited remarkable ORR performance, characterized by a high half-wave potential of 0.84 V and a low Tafel slope of 57.9 mV dec-1. To gain a comprehensive understanding of its catalytic behavior, a tailored temperature-controlled scanning electrochemical microscopy (SECM) was employed, enabling the mapping of reactivity distribution under simulated operating conditions while preserving structural integrity. Liquid zinc-air batteries (ZABs) with this electrocatalyst excelled, reaching 175 mW/cm2 power density and enduring 1240 cycles. The electrospun membrane catalyst enabled both button and flexible ZABs, adaptable to diverse environments. This study advances non-precious metal electrocatalyst design and offers insights for ZAB applications, fostering green energy prospects.

A novel pulse liquid immersion cooling strategy for Lithium-ion battery pack

Ensuring the lithium-ion batteries’ safety and performance poses a major challenge for electric vehicles. To address this challenge, a liquid immersion battery thermal management system utilizing a novel multi-inlet collaborative pulse control strategy is developed. Moreover, different cooling methods (cooling structures, immersion coolants and pulse control method) are numerically investigated to assess their impact. Compared with other structural schemes, the battery module using baffles with fish-like perforations for the 5-in and 5-out scheme demonstrates superior cooling capability while reducing external power consumption. Furthermore, the utilization of FC-3283 exhibits better comprehensive performance compared to AC-100 and mineral oil. Notably, in terms of pulse cooling, when the output ratio reaches 50 %, the battery pack temperature can not only be maintained within a reasonable range, but also the time-averaged pump power consumption decreases by 87.6 % compared to the bottom inlet and top outlet scheme. At the same average flow rate, the liquid immersion battery thermal management system with output ratio of 25 % is the optimal choice for the trade-off between cooling performance and flow resistance, and compared with the bottom inlet and top outlet scheme, the maximum temperature and maximum temperature difference decrease by 23.7 % and 13.9 %, respectively.

Effects of Li1.3Al0.3Ti1.7(PO4)3 solid-state electrolytes on the safety of hybrid solid–liquid batteries

Hybrid solid–liquid batteries (HSLBs) are emerging as promising solutions to address the safety issues of lithium-ion batteries. However, the effects of solid-state electrolytes (SSEs) on battery safety remain unclear, hindering the large-scale application of HSLBs. This paper presents a comprehensive investigation on the safety performance of HSLBs with different amounts of nano-sized Li1.3Al0.3Ti1.7(PO4)3 (LATP) SSEs in the LiNi0.9Co0.05Mn0.05O2 cathode under thermal, electrical, and mechanical abuse conditions. The HSLBs with LATP SSEs exhibit significantly enhanced tolerance to overcharge, as the battery with 5 wt% LATP does not go into thermal runaway throughout the whole overcharge process. In-depth characterizations reveal that the LATP additives experience electrochemical delithiation during overcharge and generate a protective coating layer on the cathode surface, thus effectively mitigating the cathode structural changes and cathode-electrolyte interfacial reactions. Benefiting from the coating layer, the HSLBs with LATP SSEs also exhibit reduced temperature rise rate and retarded thermal runaway during the accelerating rate calorimetry and oven tests, as well as enhanced rate performance and cycling stability. Finally, the safety, electrochemical performance, and cost of HSLBs and conventional LIBs are comprehensively compared through a radar graph, aiming to provide guidance for the rational design of high–energy density and high-safety batteries.

Fabrication of abundant oxygen vacancies in MOF-derived (Fe,Co)3O4 for oxygen evolution reaction and as an air cathode for zinc-air batteries

Metal-organic frameworks (MOFs) find wide-ranging applications owing to their adjustable structures, diverse compositions, and large specific surface area. In this work, MOFs materials were grown in situ on carbon cloth, yielding self-supported electrodes VO-(Fe,Co)3O4@CC rich in oxygen vacancies through a simple high-temperature annealing treatment utilizing NaBH4 as an etchant. Thus the resulting self-supported electrode VO-(Fe,Co)3O4@CC exhibited excellent oxygen evolution reaction (OER) performance, achieving an overpotential of merely 288 mV at 10 mA cm−2, along with a low Tafel slope of 31.39 mV dec-1, and demonstrating robust long-term activity and stability. In addition, a liquid zinc-air battery was assembled utilizing the prepared VO-(Fe,Co)3O4@CC as an air cathode, achieving a high open-circuit voltage of 1.46 V and a high peak power density of 89.06 mW cm−2, and it maintained excellent cycling stability during cyclic charging and discharging (with a current density of 2 mA cm−2) over a 32 h period. Meanwhile, the self-supported electrode VO-(Fe,Co)3O4@CC served as an air cathode for assembling an all-solid-state flexible zinc-air battery (ZAB), demonstrating a high peak power density (38.21 mW cm−2) and exhibiting favorable cycling stability. This experiment offers insights into the potential application of MOF-derived electrocatalysts in water decomposition and zinc-air batteries.

Collaborative interface optimization strategy guided Fe3C/MnO-NC electrocatalysts for rechargeable flexible zinc-air batteries

The flexible zinc-air batteries characterized by heightened flexibility, durability, and high electrochemical performance have been recognized as the most promising candidates for the next-generation wearable electronic products. Herein, a novel Fe3C/MnO heterostructure coupled with nitrogen-doped carbon (Fe3C/MnO-NC) derived from metal-organic frameworks (MOFs) is innovatively designed as a highly active bifunctional electrocatalyst. The Fe3C/MnO heterostructure in Fe3C/MnO-NC can effectively regulate the electronic structure to optimize the free energy of the related intermediates in the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER), consequently improving the catalytic properties of liquid Zn-air battery with impressive power density and outstanding stability. The theoretical calculations reveal that the design of the heterogeneous Fe3C/MnO interface effectively tunes the electron distribution to optimize the adsorption energy of ORR/OER related intermediates and significantly promotes intrinsic ORR/OER activities. Notably, the flexible Zn-air battery was also assembled with the bifunctional Fe3C/MnO-NC electrocatalyst and the prepared polyacrylamide polyacrylic acid-glycerin composite gel polymer electrolyte (PAM-PAA-Gly GPE). The electrochemical results reveal that the constructed flexible Zn-air battery can achieve a remarkable open-circuit voltage of 1.50 V and sustain stable cycling for 48 h (288 cycles). This work not only sheds light on the effective utilization of Fe3C/MnO-NC catalysts but also highlights the potential of hydrogels in achieving high-performance wearable Zn-air batteries.

Construction of atom-scale Co/Fe/Ni M-N-C active sites within nitrogen-doped carbon spheres for high-performance bifunctional oxygen catalysts in rechargeable zinc-air batteries

Developing carbon-based catalysts with metal‑nitrogen‑carbon (M-N-C) active sites as efficient and low-cost bifunctional catalysts to replace precious metal catalysts for rechargeable zinc-air batteries devices has garnered significant attention. Herein, nitrogen-doped submicron carbon-based spherical bifunctional electrocatalysts (CNPD-CoFeNi) with abundant atom-scale Co/Fe/Ni M-N-C active sites and defects were synthesized. The introduction of massive amounts of Zn species increases the spatial distance of Co/Fe/Ni metal sites to prevent aggregation during pyrolysis, and the evaporation of Zn at high temperatures creates defects synergizing with M-N-C. Consequently, CNPD-CoFeNi possesses a stable carbon-based spherical structure, high electrical conductivity, rich nitrogen content, abundant atom-scale Co/Fe/Ni M-N-C active sites, and defects, displaying outstanding durability, oxygen reduction reaction (ORR) activity with a half-wave potential of 0.87 V, and satisfactory OER performance, surpassing or comparable with the state-of-art Pt/C and RuO2, respectively. Notably, liquid Zn-air batteries with CNPD-CoFeNi catalyst exhibit an exceptional high peak power density of 146.5 mW cm−2 and stable charge-discharge cycling over 270 h, outperforming Pt/C-RuO2 based devices. Additionally, the all-solid-state Zn-air battery also displays satisfactory practicability and stability. The synthesis strategy and its remarkable results provide valuable guidance and inspiration for the future advancement of precious metal substitutes in ORR/OER and rechargeable zinc-air batteries.

Phase-field modeling of lithium dendrite deposition process: When an internal short circuit occurs

Lithium dendrite growth is the main trigger for internal short circuits (ISC) of lithium-ion batteries. This paper investigates the lithium dendrite growth during the whole short circuit evolution process. In this paper, the lithium dendrite growth is divided into the initial deposition of the initial operation and the secondary deposition due to the internal short circuit. Firstly, a two-dimensional model based on the phase-field theory is developed and the growth in static electrolyte is investigated. Secondly, we summarize the whole evolution process and analyze the internal structural changes as well as the external features due to the internal short circuit. Based on this analysis, a model of secondary deposition in a flowing electrolyte is proposed. The model takes into account the effect of the flowing electrolyte on the dendrites. Finally, we investigate the growth of dendrites during secondary deposition. Due to an internal short circuit that damages the separator, a flowing electrolyte appears around the damaged region. This flowing electrolyte leads to uneven growth of dendrites, with “splitting” and “branch inhibition”. This phenomenon will accelerate the continued deposition of dendrites and induce a secondary internal short circuit. This work provides a quantitative simulation model for dendrite growth when an ISC occurs. Moreover, it also provides a reference for designing the structure of liquid batteries with high cycle times and safety.

The thermophysical properties of Ga-Na liquid alloys

In this study, the thermophysical properties of Ga-Na liquid alloys were investigated. Based on the literature, the reference equations for surface tension and viscosity for liquid Ga were given. The density, surface tension, and viscosity were measured using the discharge crucible method in a temperature range of 573–873 K. The chemical composition of Ga-Na alloys was selected to show the effect of Na dissolution in Ga as potential liquid batteries. It was noticed that the addition of Na to Ga reduced all investigated properties, with the effect being greatest for surface tension. The experimental value shows good agreement with the proposed models (Butler for surface tension and Gasior, Kaptay, and Moelwyn-Hughes for viscosity).

Heterointerface engineering of yolk-shell-structured Mn2O3/RuO2 for boosting oxygen electrocatalysis in rechargeable liquid and flexible zinc-air batteries

Rational construction of high-efficient bifunctional oxygen electrocatalysts is of crucial significance for rechargeable Zn-air batteries (ZABs). Here, the yolk-shell-structured Mn2O3/RuO2 heterojunction is purposely constructed via the Kirkendall effect as a robust bifunctional oxygen electrocatalyst for simultaneously driving oxygen evolution and reduction reactions (OER and ORR). The strong interactions between Mn2O3 and RuO2 induces the surface reconstruction that brings the electronic transfer from Mn to Ru, and the changes of coordination environments of metal atoms. Meanwhile, the yolk-shell structure enables maximum contact of the active sites with the electrolyte and prevents the dissolution and peroxidation of active species. As a result, the yolk-shell-structured Mn2O3/RuO2 shows an outstanding bifunctional activity with a very low potential gap of ΔE = 0.60 V. Moreover, the ZABs assembled with Mn2O3/RuO2 render a large open circuit voltage of 1.53 V, a high specific capacity of 742.1 mA h g−1 and an exceptional cycling stability over 850 h that significantly outperforms those of Pt/C+RuO2-based ZABs. Moreover, the self-made flexible solid-state ZAB with Mn2O3/RuO2 cathode also shows good charge–discharge reversibility and flexibility at different bending angles. This work provides a feasible method for the design of efficient oxygen electrocatalysts to promote the practical application of ZABs.