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Non-nucleophilic and non-fluorinated compounds are the most important class of solvents to enable sustainable rechargeable magnesium batteries but suffer from poor stability due to the formation of an unstable solid–electrolyte-interphase.

Aqueous manganese (Mn)-based batteries are promising candidates for grid-scale energy storage due to their low-cost, high reversibility, and intrinsic safety. However, their further development is impeded by controversial reaction mechanisms and low energy density with unsatisfactory cycling stability. Here, we summarized various types of emerging aqueous Mn-based batteries based on the active redox couples, including liquid–solid deposition/dissolution reactions of Mn0/Mn2+ and Mn2+/MnO2, liquid–liquid conversion reactions of Mn2+/Mn3+ and MnO42−/MnO4−, and solid–solid intercalation reaction of XMnOy/MnOy (X: cations) with manganese oxide as the host materials. A critical review of the fundamental understanding of their physicochemical properties in each reaction, scientific challenges, and improvement strategies is presented. Finally, perspectives on aqueous Mn-based batteries design for future commercialization are highlighted.

Summary Conventional aqueous electrolytes suffer from a narrow voltage window due to water decomposition. Highly concentrated electrolytes expand the voltage window; however, they are limited by high cost and potential toxicity. Here, we develop a hydrogen bond-anchored electrolyte by introducing sulfolane as hydrogen bond acceptor to limit water activity. The designed electrolyte expands the voltage window to 3.4 V (1.3–4.7 V versus Li+/Li) and forms a hierarchical anode-electrolyte interphase to suppress the hydrogen evolution reaction. An aqueous Li4Ti5O12/LiMn2O4 full cell achieved 141 W h kg−1 for 300 cycles at 1 C and 125 W h kg−1 for 1,000 cycles at 5 C with a high Coulombic efficiency of 99.5%–99.9%. On-line electrochemical mass spectroscopy shows negligible hydrogen/oxygen gas evolution upon cycling, further confirming the stability of the designed electrolyte. This work demonstrates a rational and effective approach to suppress the hydrogen evolution reaction and achieve stable high-voltage aqueous batteries.

Oligo(ethylene glycol) (OEG)-substituted viologens enable superior cycling stability of the first-electron redox reaction and accessibility of the second-electron energy storage in aqueous organic redox flow batteries (AORFBs).

Direct probing of metal–oxygen chemistry at the solid/liquid interface is essential to unravel the reaction mechanism of metal–air batteries. Ambient pressure X-ray photoelectron spectroscopy (APXPS) is an effective tool to study metal–oxygen reactions but has been limited to solid-state environments. Here, for the first time, we demonstrate in situ probing of potassium oxygen reduction/evolution reaction (ORR/OER) via APXPS in ionic liquid-based air batteries. We reveal the formation and oxidation of K2O and K2O2 in K–O2 batteries, highlighting new reaction pathways in addition to the widely established one-electron process in K–O2 batteries. Importantly, we show that the formation and subsequent oxidation of K2O2 trigger irreversible cell chemistry, which could be responsible for capacity decay in K–O2 batteries. We further show that common impurities in air such as H2O and CO2 reduce chemical reversibility of ORR and OER. This study reveals root causes of irreversible cell chemistry in K–air batteries via direct probing of ionic liquid-based air batteries via APXPS, which can be widely applied to study the chemistry of solid/liquid interfaces of metal–air batteries.

Polysulfide is one of the most promising aqueous redox chemistries for grid storage owing to its inherent safety, high energy and low cost. However, its poor cycle life resulting from polysulfide cross-over has prohibited its successful commercialization. To exploit low-cost and high-capacity polysulfide flow batteries with industrial-relevant cycling stability, we develop a charge-reinforced ion-selective membrane to retain polysulfide/iodide, restrain membrane swelling and prevent water/OH− migration. The polysulfide/polyiodide static cell demonstrates a low capacity decay rate (0.005% per day and 0.0004% per cycle) over 2.9 months (1,200 cycles) at a 100% state of charge. A flow cell containing 4.0 M KI/2.0 M K2S2 demonstrated stable cycling at 17.9 Ah l−1posolyte+negolyte over 3.1 months (500 cycles). Small-angle X-ray scattering and in-situ attenuated total reflectance–Fourier transform infrared/solid-state NMR revealed reduced water cluster size and restrained water movement in the charge-reinforced ion-selective membrane compared to commercial Nafion membrane. Techno-economic analysis shows that the developed polysulfide flow battery promises competitive levelized cost of storage for long-duration energy storage. The development of aqueous redox flow batteries (ARFBs) has been plagued by high material costs and poor operating stability. Here the authors report a membrane design to enable polysulfide-based ARFBs with minimal capacity decay over long cycles and durations as well as competitive cost-effectiveness.

Developing low-potential, fast-kinetics and highly concentrated anolyte materials is one of the major challenges for nonaqueous redox flow batteries (NRFBs). Organosulfides exhibit promising potentials for NRFBs owing to their high solubility and structure diversity. However, they suffer from poor reaction kinetics and intermediate reversible potential, leading to poor roundtrip efficiency and low full cell voltage. Herein, we report diphenyl ditelluride (PDTe) as a low-potential and fast-kinetics anolyte candidate. The reversible potential of PDTe (average 1.97 V vs. Li/Li+) is lower than that of its sulfur counterpart PDS (2.25 V), which offers higher full cell voltages. We demonstrated a Li/2.5 M PDTe half-cell with a high volumetric capacity (128 Ah L−1PDTe), and high coulombic and energy efficiency (>99.5% and 84.1%) over 100 cycles. A Li/0.1 M PDTe flow cell achieved a stable long cycling over 260 cycles (38 days) at 1.5 mA cm−2. Coupling with lithium iodide (LiI) catholyte, the PDTe/LiI full cells demonstrated stable cycling over 120 cycles. Density functional theory calculation reveals that the cleavage of ditelluride bond requires a much lower bond dissociation energy than that of disulfide bond, which significantly reduces battery voltage hysteresis (by 429 mV). This study demonstrates the promising potential of organotellurides as anolytes for energy storage applications.

Redox flow batteries (RFBs) are a promising technology for large-scale energy storage. Rapid research developments in RFB chemistries, materials and devices have laid critical foundations for cost-effective and long-lasting RFB systems. However, the lack of consistency in testing methods and assessment metrics makes it challenging to compare reported RFBs and evaluate their potential for practical applications. Here we discuss RFB assessment methods and performance metrics in direct relation to their working principles and degradation mechanisms. We first introduce basic cell attributes and performance metrics and describe common misconceptions in testing and performance comparison. We discuss major RFB decay mechanisms and highlight bottlenecks in organic, inorganic and solid-hybrid RFBs. Testing protocols, reporting practices and comparison criteria are proposed under a general framework of symmetric and asymmetric full RFBs. These recommendations can be broadly applied to a wide range of flow battery chemistries to facilitate future benchmarking and RFB development. Performance assessments of redox flow batteries (RFBs) can be challenging due to inconsistency in testing methods and conditions. Here the authors summarize major performance metrics of RFBs, analyse their degradation mechanisms and propose testing protocols for benchmarking.

Lithium–sulfur (Li–S) batteries promise high theoretical specific energy density (2600 W h kg−1), low cost and eco-friendliness. However, their practical development is limited by the shuttle of lithium polysulfides (LiPSs) and sluggish reaction kinetics. Herein, we develop a sulfur conversion catalyst based on MnCo2O4.5 modified graphitized carbon nitride nanosheets (CNMCO) to enhance the LiPS immobilization and redox conversion for Li–S batteries. Benefiting from its dense nano-lamellar structure and polar surface, CNMCO synergistically serves as a physical impediment and allows chemical entrapment for LiPSs. In addition, CNMCO exhibits a high electrocatalytic activity towards LiPS conversion as well as Li2S nucleation and decomposition, which were revealed by cyclic voltammetry and density functional theory calculations. As a consequence, the cell with the multi-functional CNMCO/PP separator exhibits substantially improved electrochemical performance, achieving an enhanced rate capability of ∼600 mA h g−1 at 4C, and an outstanding cycling stability with a low capacity fading rate of 0.032% per cycle for 500 cycles at 2C. This work reports an effective strategy to achieve the immobilization of LiPSs and effective catalytic redox conversion for high-performance Li–S batteries.

Aqueous manganese (Mn) batteries based on the deposition–dissolution reaction of Mn2+/MnO2(s) have attracted great attention due to their low cost, high voltage, and high safety. However, the incomplete dissolution of MnO2 and exfoliated MnO2 from mechanical cracks of thick MnO2 layers (lost capacity) prevent long-term stable operation at high areal capacity (>2.0 mA h cm−2). Here, we propose a mediator strategy to facilitate MnO2 dissolution and recover ‘lost’ capacity from exfoliated MnO2, which improves the cycling stability at high areal capacity. UV-visible spectroscopy was used to verify the working principle of the mediator strategy. The iodide (I−) mediator chemically reduces solid MnO2 to form Mn2+ and oxidizes to tri-iodide (I3−), which then can get reduced at the electrode returning to I−, completing one mediation cycle. The zinc–manganese (Zn–Mn) battery with the iodide mediator shows improved cycling stability at 2.5 mA h cm−2 (400 vs. 100 cycles, static mode) and 15 mA h cm−2 (225 vs. 60 cycles, flow mode). We further increased the areal capacity and demonstrated 50 mA h cm−2 for more than 50 cycles, which is the highest areal capacity achieved for reported Zn–Mn batteries. This mediator strategy is introduced into aqueous Mn-based batteries for the first time, which could also shed light on other deposition-based batteries to achieve stable operation at high areal capacity.

Hybrid redox flow batteries (RFBs) offer a much higher energy density compared to all-liquid RFBs. However, the negative electrodes of hybrid RFBs normally utilize metal deposition reactions (e.g., zinc metal), which suffer from severe dendrite growth and poor long-term stability, especially at high areal capacities and high current densities. Herein, we propose and demonstrate the use of high-loading solid conversion electrodes to replace metal deposition electrodes to achieve high cycling stability at high areal capacities/current densities in hybrid RFBs. Using a Fe3O4/Fe(OH)2 conversion negative electrode as an example coupled with a Fe(CN)63−/Fe(CN)64− posolyte, we demonstrated conversion type all-iron hybrid RFBs with an unprecedentedly high cycling areal capacity of 126.6 mA h cm−2 at 50 mA cm−2 for 200 cycles (1000 hours) and 215 mA h cm−2 at 60 mA cm−2 for 100 cycles (700 hours) without capacity decay. The solid conversion electrode eliminates dendrite issues and the limitations of metal areal capacity, and demonstrates superior areal capacity, current density, and cycling stability compared to conventional zinc metal negative electrodes. This approach offers a new direction for developing high-energy, low-cost, and long-lasting hybrid RFBs for large-scale grid energy storage applications.

Lithium metal is the most attractive anode material owing to its lowest electrochemical potential and high theoretical specific capacity. However, uncontrolled dendrite growth leads to severe safety issues and poor electrochemical stability, hindering its practical application. Herein, we report a dendrite-free and reversible Li metal anode enabled by graphene aerogel (GA) host with three-dimensional gradient porous structure. The gradient porous structure facilitates reversible Li plating/stripping with high Li/carbon mass ratio (Li/C = 5) and realizes uniform Li distribution on the electrode surface. This approach achieves a stable voltage profile for a long lifespan (1300 h at 2 mA cm−2 for 2 mAh cm−2 and 1000 h at 5 mA cm−2 for 3 mAh cm−2) with superior high symmetric cumulative capacity (2500 mAh cm−2). Coupling the LiGA anode with a LiFePO4 (LFP) cathode, a stable cycling of the full LiGA-LFP cells for 200 cycles at 2 C were achieved, demonstrating the promising practical applications of LiGA in advanced rechargeable batteries.

Metal–air batteries promise high gravimetric energy and low material cost but suffer from poor cycle life due to severe cathode side reactions. Here, the reactivity of metal superoxide is demonstra...

Nonaqueous lithium–oxygen (Li–O2) batteries have received intensive research attention owing to their potential to provide gravimetric energy density 2–5 times that of conventional Li-ion batteries. However, Li–O2 batteries are suffering from poor cycle life, low rate capability and poor round-trip efficiency. In-depth understanding on the reaction and degradation mechanism is the prerequisite for rational electrode and electrolyte design for efficient and long-life Li–O2 batteries. In this review, we analyze recent progress in oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) mechanism. We discuss on-going debates and open questions related to OER processes including the reaction intermediates, the origin for the side reactions, the reaction interface and the catalysis mechanism. We provide insights into the sources of discrepancies and highlight future research directions in deepening the understanding of Li–O2 reactions and strategies in mitigating the severe instability between the reaction intermediates and cell components for efficient and long-life Li–O2 batteries.

We propose and demonstrate the concept of a self-mediating redox flow battery that employs inherently present redox shuttles to access charges stored in solid electrode materials without circulatin...

Superoxide (LiO2) formation on charging is one of the major causes of poor cycle life of Li–O2 batteries. The underlying mechanism controlling LiO2 formation remains elusive. Here, we reveal that t...

Having transformed our way of life, rechargeable batteries are poised for exponential growth over the coming decade, notably due to the wider adoption of electric vehicles. An international expert panel proposes a combination of vision, innovation and practice for feasible pathways toward sustainable batteries.

We survey the literature on family firms with a focus on Asian countries. We begin with identifying three key motivational drivers of international research on family business—their dominance, relative performance, and extent of family embeddedness in the business. Second, we provide a brief survey of family firms in eight Asian economies with a focus on the history and current challenges faced by family firms in each country. Third, we document the variety of family firm definitions used in the literature and the resulting difficulty in drawing inferences due to a lack of definitional consistency. Fourth, we discuss thestrategic advantages family assets such as legacy and networks bring to family firms in the Asian context. Fifth, we identify some unique challenges family firms face in their countries, and provide examples of how ownership and succession structures mitigate these challenges. We close this survey by suggesting some open research questions relevant for Asian family firms.

Conjugated sulfonamides have been demonstrated as cathodes with high redox potentials and exceptional atmospheric stability, providing a sustainable alternative to traditional inorganic materials used in commercial lithium-ion batteries.

CBL family proteins (CBL, CBLB and CBLC in mammals) are E3 ubiquitin ligases of protein tyrosine kinases. CBL mediates the lysosomal degradation of activated EGFR through K63-linked ubiquitination, while CBLC has an oncogenic function by positively regulating EGFR activation through K6 and K11-linked ubiquitination in EGFR mutant lung adenocarcinoma (LAD). Here, we used immunoprecipitation and mass spectrometry to study the CBLC interactome, and found that CBLC is also involved in cell cycle regulation by stabilizing Aurora kinase A (AURKA). CBLC interacted with the kinase domain of AURKA and positively regulated the stability of AURKA by conjugating monoubiquitination and K11/K63-linked polyubiquitination, which are protective from degrading K11/K48 polyubiquitination. CBLC depletion markedly decreased the half-life of AURKA in cycloheximide-treated LAD cells. When LAD cells were synchronized with double thymidine block at the G1/S boundary and then released into mitotic arrest, CBLC depletion delayed the accumulation and activation of AURKA and prevented cancer cells from entering mitosis. CBLC deficiency significantly delayed cell cycle progression, reduced the mitotic population, and increased apoptosis of LAD cells. Targeting CBLC inhibited tumor growth of LAD cells and enhanced their sensitivity to paclitaxel in xenograft models. Immunohistochemical staining of the tissue microarray also revealed a positive correlation between the expression of CBLC and AURKA in normal and LAD tissues, further supporting the positive regulation of AURKA expression by CBLC. In summary, these findings indicate that the oncogenic E3 ligase CBLC plays a role in mitotic entry by stabilizing AURKA via ubiquitination in LAD. This work demonstrates that targeting CBLC combined with paclitaxel might be a potential option for the treatment of LAD patients who have no available targeted therapies.

Lithium–oxygen batteries promise high energy but suffer from poor cycle life owing to the generation of highly reactive singlet oxygen 1O2, which rapidly deactivates the electrode and the electrolyte. Here we demonstrate an effective strategy to suppress 1O2 using redox mediators. Using operando spectroscopy techniques, we show that 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), as a model redox mediator, drastically reduces 1O2 formation, increases the yield of ground state 3O2, and reduces the by-product generation. The 1O2 suppression effect is attributed to an increased intersystem crossing rate induced by redox mediators, with which the relaxation of a singlet-state intermediate to a triplet-state one is accelerated. We further show that this 1O2 suppression effect applies universally across six common redox mediators with up to three orders of magnitude higher 1O2 suppression efficiency compared to 1,4-diazabicyclo[2.2.2]octane (DABCO), the most efficient quencher used in Li–O2 batteries to date. From the comparison of the investigated mediators we discuss the plausible governing principle dictating redox mediators’ effectiveness in suppressing 1O2. Our study achieves effective 1O2 suppression and provides guidelines for designing redox mediators for efficient and reversible lithium–oxygen batteries.

Sulfur-based redox materials are promising next-generation energy storage solutions. Identifying electrode and electrolyte properties that facilitate polysulfide reduction reactions is critical for...

Summary Flow batteries allow independent scaling of power and energy and permit low-cost materials for large-scale energy storage. However, they suffer from low-energy densities or poor scalability when a solid electrode is used in hybrid systems (zinc or lithium metals). Breaking the convention of pumping fluids, we propose and demonstrate a new flow battery invention that transports active material via rotation of flexible electrode belts made from high-energy-density solid electrode materials (flexible solid flow electrode). Using this strategy, we demonstrated a fully scalable aqueous solid-liquid hybrid flow battery using a lithium titanium phosphate (LTP) flexible anode belt coupled with lithium iodide (LiI) catholyte. This strategy of the circulating flexible solid electrode can be readily applied to existing solid-liquid hybrid flow batteries (e.g., Zn-I2, Zn-Br2, Li-I2, Li-polysulfide, etc.) and allows many types of solid electrode materials in a flow battery platform without constraints in solubility or scalability.

Lithium–sulfur batteries offer a high theoretical gravimetric energy density and low cost, but the full utilization of the sulfur electrode has been limited by the premature passivation of insulati...