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Prussian blue analogs (PBAs) are promising insertion‐type cathode materials for different types of aqueous batteries, capable of accommodating metal or non‐metal ions. However, their practical application is hindered by their susceptibility to dissolution, which leads to a shortened lifespan. Herein, we have revealed that the dissolution of PBAs primarily originates from the locally elevated pH of electrolytes, which is caused by the proton co‐insertion during discharge. To address this issue, the water‐locking strategy has been implemented, which interrupts the generation and Grotthuss diffusion of protons by breaking the well‐connected hydrogen bonding network in aqueous electrolytes. As a result, the hybrid electrolyte enables the iron hexacyanoferrate to endure over 1000 cycles at a 1 C rate and supports a high‐voltage pH‐decoupled cell with an average voltage of 1.95 V. These findings provide insights for mitigating the dissolution of electrode materials, thereby enhancing the viability and performance of aqueous batteries. [ABSTRACT FROM AUTHOR]

In the pursuit of next‐generation ultrahigh‐energy‐density Li−O2 batteries, it is imperative to develop an electrolyte with stability against the strong oxidation environments. N,N‐dimethylacetamide (DMA) is a recognized solvent known for its robust resistance to the highly reactive reduced oxygen species, yet its application in Li−O2 batteries has been constrained due to its poor compatibility with the Li metal anode. In this study, a rationally selected hydrofluoroether diluent, methyl nonafluorobutyl ether (M3), has been introduced into the DMA‐based electrolyte to construct a localized high concentration electrolyte. The stable −CH3 and C−F bonds within the M3 structure could not only augment the fundamental properties of the electrolyte but also fortify its resilience against attacks from O2− and 1O2. Additionally, the strong electron‐withdrawing groups (−F) presented in the M3 diluent could facilitate coordination with the electron‐donating groups (−CH3) in the DMA solvent. This intermolecular interaction promotes more alignments of Li+‐anions with a small amount of M3 addition, leading to the construction of an anion‐derived inorganic‐rich SEI that enhances the stability of the Li anode. As a result, the Li−O2 batteries with the DMA/M3 electrolyte exhibit superior cycling performance at both 30 °C (359th) and −10 °C (120th). [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The increasing demand for high‐energy storage systems has propelled the development of Li‐air batteries and Li‐O2/CO2 batteries to elucidate the mechanism and extend battery life. However, the high charge voltage of Li2CO3 accelerates the decomposition of traditional sulfone and ether electrolytes, thus adopting high‐voltage electrolytes in Li‐O2/CO2 batteries is vital to achieve a stable battery system. Herein, we adopt a commercial carbonate electrolyte to prove its excellent suitability in Li‐O2/CO2 batteries. The generated superoxide can be captured by CO2 to form less aggressive intermediates, stabilizing the carbonate electrolyte without reactive oxygen species induced decomposition. In addition, this electrolyte permits the Li metal plating/stripping with a significantly improved reversibility, enabling the possibility of using ultra‐thin Li anode. Benefiting from the good rechargeability of Li2CO3, less cathode passivation, and stabilized Li anode in carbonate electrolyte, the Li‐O2/CO2 battery demonstrates a long cycling lifetime of 167 cycles at 0.1 mA·cm–2 and 0.25 mAh·cm–2. This work paves a new avenue for optimizing carbonate‐based electrolytes for Li‐O2 and Li‐O2/CO2 batteries. [ABSTRACT FROM AUTHOR]

The severe performance degradation of high‐capacity Li−O2 batteries induced by Li dendrite growth and concentration polarization from the low Li+ transfer number of conventional electrolytes hinder their practical applications. Herein, lithiated Nafion (LN) with the sulfonic group immobilized on the perfluorinated backbone has been designed as a soluble lithium salt for preparing a less flammable polyelectrolyte solution, which not only simultaneously achieves a high Li+ transfer number (0.84) and conductivity (2.5 mS cm−1), but also the perfluorinated anion of LN produces a LiF‐rich SEI for protecting the Li anode from dendrite growth. Thus, the Li−O2 battery with a LN‐based electrolyte achieves an all‐round performance improvement, like low charge overpotential (0.18 V), large discharge capacity (9508 mAh g−1), and excellent cycling performance (225 cycles). Besides, the fabricated pouch‐type Li–air cells exhibit promising applications to power electronic equipment with satisfactory safety. [ABSTRACT FROM AUTHOR]

The performance of electrode material is correlated with the choice of electrolyte, however, how the solvation has significant impact on electrochemical behavior is underdeveloped. Herein, N‐heteropentacenequinone (TAPQ) is investigated to reveal the solvation effect on the performance of sodium‐ion batteries in different electrolyte environment. TAPQ cycled in diglyme‐based electrolyte exhibits superior electrochemical performance, but experiences a rapid capacity fading in carbonate‐based electrolyte. The function of solvation effect is mainly embodied in two aspects: one is the stabilization of anion intermediate via the compatibility of electrode and electrolyte, the other is the interfacial electrochemical characteristics influenced by solvation sheath structure. By revealing the failure mechanism, this work presents an avenue for better understanding electrochemical behavior and enhancing performance from the angle of solvation effect. [ABSTRACT FROM AUTHOR]

The dendrite growth of Li anodes severely degrades the performance of lithium-oxygen (Li-O2) batteries. Recently, hybrid solid electrolyte (HSE) has been regarded as one of the most promising routes to tackle this problem. However, before this is realized, the HSE needs to simultaneously satisfy contradictory requirements of high modulus and even, flexible contact with Li anode, while ensuring uniform Li+ distribution. To tackle this complex dilemma, here, an HSE with rigid Li1.5Al0.5Ge1.5(PO4)3 (LAGP) core@ultrathin flexible poly (vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) shell interface has been developed. The introduced large amount of nanometer-sized LAGP cores can not only act as structural enhancer to achieve high Young's modulus but can also construct Li+ diffusion network to homogenize Li+ distribution. The ultrathin flexible PVDF-HFP shell provides soft and stable contact between the rigid core and Li metal without affecting the Li+ distribution, meanwhile suppressing the reduction of LAGP induced by direct contact with Li metal. Thanks to these advantages, this ingenious HSE with ultra-high Young's modulus of 25 GPa endows dendrite-free Li deposition even at a deposition capacity of 23.6 mAh. Moreover, with the successful inhibition of Li dendrites, the HSE-based quasi-solid-state Li-O2 battery delivers a long cycling stability of 146 cycles, which is more than three times that of gel polymer electrolyte-based Li-O2 battery. This new insight may serve as a starting point for further designing of HSE in Li-O2 batteries, and can also be extended to various battery systems such as sodium-oxygen batteries. [ABSTRACT FROM AUTHOR]

The limited triple‐phase boundaries (TPBs) in solid‐state cathodes (SSCs) and high resistance imposed by solid electrolytes (SEs) make the achievement of high‐performance all‐solid‐state lithium‐oxygen (ASS Li‐O2) batteries a challenge. Herein, an adjustable‐porosity plastic crystal electrolyte (PCE) has been fabricated by employing a thermally induced phase separation (TIPS) technique to overcome the above tricky issues. The SSC produced through the in‐situ introduction of the porous PCE on the surface of the active material, facilitates the simultaneous transfer of Li+/e−, as well as ensures fast flow of O2, forming continuous and abundant TPBs. The high Li+ conductivity, softness, and adhesion of the dense PCE significantly reduce the battery resistance to 115 Ω. As a result, the ASS Li‐O2 battery based on this adjustable‐porosity PCE exhibits superior performances with high specific capacity (5963 mAh g−1), good rate capability, and stable cycling life up to 130 cycles at 32 °C. This novel design and exciting results could open a new avenue for ASS Li‐O2 batteries. [ABSTRACT FROM AUTHOR]

Abstract: Rechargeable sodium–oxygen (Na–O2) batteries are of interest due to their high specific capacity, high equilibrium potential output, and the abundance of sodium resources; however, their cycle life is still very poor due to instability of electrolytes and especially the uncontrollable growth of Na dendrites. Herein, as a proof‐of‐concept experiment, a facile and low‐cost strategy is first proposed and demonstrated to effectively suppress growth of Na dendrites by using a fibrillar polyvinylidene fluoride film (f‐PVDF) with nonthrough pore as a multifunctional blocking interlayer. Unexpectedly, the f‐PVDF interlayer endows Na–O2 battery with superior electrochemical performances, including high rate capability and long cycle life (up to 87 cycles), which is superior to those of the compact PVDF (c‐PVDF), PVDF with through pores (p‐PVDF), polyethylene oxide (PEO), and conventional polytetrafluoroethylene (PTFE) counterparts due to the following combined advantages: (1) the stronger CF polar function groups provide a better affinity to Na ions, thus enabling a more homogeneous Na deposition than that of CO function groups in PEO interlayer; (2) compared with c‐PVDF and p‐PVDF interlayers, f‐PVDF holds more electrolyte uptake for higher ion conductivity; (3) the good wettability of the f‐PVDF interlayer with electrolyte benefits Na dendrite suppression compared with PTFE interlayer. [ABSTRACT FROM AUTHOR]

Lithium–air (Li–air) batteries have recently received much attention due to their extremely high theoretical energy densities. The significantly larger theoretical energy density of Li–air batteries is due to the use of a pure lithium metal anode and the fact that the cathode oxidant, oxygen, is stored externally since it can be readily obtained from the surrounding air. However, before Li–air batteries can be realized as high-performance, commercially viable products there are still numerous scientific and technical challenges that must be overcome, from designing the cathode structure, to optimizing the electrolyte compositions and elucidating the complex chemical reactions that occur during charge and discharge. The scientific obstacles that are related to the performance of Li–air batteries open up an exciting opportunity for researchers from many different backgrounds to utilize their unique knowledge and skills to bridge the knowledge gaps that exist in current research projects. This review article is a summary of the most significant developments and challenges of practical Li–air batteries and the current understanding of their chemistry. [ABSTRACT FROM PUBLISHER]

Comprehensive Summary: The increasing demand for high‐energy storage systems has propelled the development of Li‐air batteries and Li‐O2/CO2 batteries to elucidate the mechanism and extend battery life. However, the high charge voltage of Li2CO3 accelerates the decomposition of traditional sulfone and ether electrolytes, thus adopting high‐voltage electrolytes in Li‐O2/CO2 batteries is vital to achieve a stable battery system. Herein, we adopt a commercial carbonate electrolyte to prove its excellent suitability in Li‐O2/CO2 batteries. The generated superoxide can be captured by CO2 to form less aggressive intermediates, stabilizing the carbonate electrolyte without reactive oxygen species induced decomposition. In addition, this electrolyte permits the Li metal plating/stripping with a significantly improved reversibility, enabling the possibility of using ultra‐thin Li anode. Benefiting from the good rechargeability of Li2CO3, less cathode passivation, and stabilized Li anode in carbonate electrolyte, the Li‐O2/CO2 battery demonstrates a long cycling lifetime of 167 cycles at 0.1 mA·cm–2 and 0.25 mAh·cm–2. This work paves a new avenue for optimizing carbonate‐based electrolytes for Li‐O2 and Li‐O2/CO2 batteries. [ABSTRACT FROM AUTHOR]