Integrated Electrode-Electrolyte Optimization to Manufacture a Real-Life Applicable Aqueous Supercapacitor with Record-Breaking Lifespan

Aqueous supercapacitors(SCs)have been regarded as a promising candidate for commercial energy storage device due to their superior safety,low cost,and environmental benignity.Unfortunately,an age-old challenge of achieving both long electrode lifespan and qualified energy-storage property blocks their practical application.Herein,we develop an electrode-electrolyte integrated optimization strategy to fulfill the real-life device requirements.Electrode optimization simultaneously regulates the nanomorphology and surface chemistry of the tungsten oxide anode,resulting in superior electrochemical performance given by an ideal“bird-nest”structure with optimal oxygen vacancy status;the anodes interact with and are protected from dissolution and structural collapse by the rationally designed hybrid electrolyte with optimized pH and facilitated cation desorption behavior.Collaboratively,a record-breaking durability of no capacitive decay after 250000 cycles is achieved.On the basis of this integrated optimization,the first aqueous pouch SCs with real-life practicability were manufactured by a soft-package encapsulation technique,which can steadily power commercial 3 C products such as tablets and smartphones and maintain safely working against extreme conditions.This work demonstrates the possibility of using aqueous energy storage devices with enhanced safety and lower cost to replace the commercial organic counterparts for wide range of daily applications.

The Critical Role of Fillers in Composite Polymer Electrolytes for Lithium Battery

With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an essential role in the safety and electrochemical performance of the cells.Composite polymer electrolytes(CPEs)are considered as one of the most promising candidates among all solid-state electrolytes due to their excellent comprehensive performance.In this review,we briefly introduce the components of CPEs,such as the polymer matrix and the species of fillers,as well as the integration of fillers in the polymers.In particular,we focus on the two major obstacles that affect the development of CPEs:the low ionic conductivity of the electrolyte and high interfacial impedance.We provide insight into the factors influencing ionic conductivity,in terms of macroscopic and microscopic aspects,including the aggregated structure of the polymer,ion migration rate and carrier concentration.In addition,we also discuss the electrode-electrolyte interface and summarize methods for improving this interface.It is expected that this review will provide feasible solutions for modifying CPEs through further understanding of the ion conduction mechanism in CPEs and for improving the compatibility of the electrode-electrolyte interface.

Progress and perspective of high-voltage lithium cobalt oxide in lithium-ion batteries

Lithium cobalt oxide(LiCoO_(2),LCO)dominates in 3C(computer,communication,and consumer)electronics-based batteries with the merits of extraordinary volumetric and gravimetric energy density,high-voltage plateau,and facile synthesis.Currently,the demand for lightweight and longer standby smart portable electronic products drives the development of the upper cut-off voltage of LCO-based batteries to further improve the energy density.However,several challenges,including irreversible structural transformation,surface degradation,cobalt dissolution and oxygen evolution along with detrimental side reactions with the electrolyte remain with charging to a high cut-off voltage(>4.2 V vs.Li/Li+),resulting in rapid capacity decay and safety issues.Based on the degradation mechanisms and latest advances of the high-voltage LCO,this review summarizes modification strategies in view of the LCO structure,artificial interface design and electrolytes optimization.Meanwhile,many advanced characterization and monitoring techniques utilized to clarify the structural and interfacial evolution of LCO during charge/discharge process are critically emphasized.Moreover,the perspectives in terms of integrating multiple modification strategies,applying gel and solid-state electrolytes,optimizing the recovery process and scalable production are presented.

Research progress in failure mechanisms and electrolyte modification of high-voltage nickel-rich layered oxide-based lithium metal batteries

High-voltage nickel(Ni)-rich layered oxide-based lithium metal batteries(LMBs)exhibit a great potential in advanced batteries due to the ultra-high energy density.However,it is still necessary to deal with the challenges in poor cyclic and thermal stability before realizing practical application where cycling life is considered.Among many improved strategies,mechanical and chemical stability for the electrode electrolyte interface plays a key role in addressing these challenges.Therefore,extensive effort has been made to address the challenges of electrode-electrolyte interface.In this progress,the failure mechanism of Ni-rich cathode,lithium metal anode and electrolytes are reviewed,and the latest breakthrough in stabilizing electrode-electrolyte interface is also summarized.Finally,the challenges and future research directions of Ni-rich LMBs are put forward.

Designing All‑Solid‑State Batteries by Theoretical Computation:A Review

All-solid-state batteries(ASSBs)with solid-state electrolytes and lithium-metal anodes have been regarded as a promis-ing battery technology to alleviate range anxiety and address safety issues due to their high energy density and high safety.Understanding the fundamental physical and chemical science of ASSBs is of great importance to battery development.To confirm and supplement experimental study,theoretical computation provides a powerful approach to probe the thermody-namic and kinetic behavior of battery materials and their interfaces,resulting in the design of better batteries.In this review,we assess recent progress in the theoretical computations of solid electrolytes and the interfaces between the electrodes and electrolytes of ASSBs.We review the role of theoretical computation in studying the following:ion transport mechanisms,grain boundaries,phase stability,chemical and electrochemical stability,mechanical properties,design strategies and high-throughput screening of inorganic solid electrolytes,mechanical stability,space-charge layers,interface buffer layers and dendrite growth at electrode/electrolyte interfaces.Finally,we provide perspectives on the shortcomings,challenges and opportunities of theoretical computation in regard to ASSBs.

Modulating microenvironments to enhance CO_(2) electroreduction performance

Microenvironments of the catalytic center,which play a vital role in adjusting electrocatalytic CO_(2) reduction reaction(ECO_(2) RR)activity,have received increasing attention during the past few years.However,controllable microenvironment construction and the effects of multi-microenvironment variations for improving ECO_(2) RR performance remain unclear.Herein,we summarize the representative strategies for tuning the catalyst and local microenvironments to enhance ECO_(2) RR selectivity and activity.The multifactor synergetic effects of microen-vironment regulation for enhancing CO_(2) accessibility,stabilizing key intermediates,and improving the performance of ECO_(2) RR catalysts are discussed in detail,as well as perspectives on the challenges when investigating ECO_(2) RR microenvironments.We anticipate that the discussions in this review will inspire further research in microenvironment engineering to accelerate the development of the ECO 2 RR for practical application.

A facile synthesis of non-aqueous LiPO_(2)F_(2) solution as the electrolyte additive for high performance lithium ion batteries

Constructing a reliable and favorable electrode-electrolyte interface is crucial to utilize the exceptional energy storage capability in commercial lithium-ion batteries.Here,we report a facile synthesis approach for the lithium difluorophosphate(LiPO_(2)F_(2))solution as an effective film-forming additive via direct adding the Li_(2)CO_(3) into LiPF6 solution at 45℃.Benefiting from the significantly reduced interface resistance(RSEI)and charge transfer impedance(Rct)of both the cathode and anode by adding the prepared LiPO_(2)F_(2)solution into a baseline electrolyte,the cycling performance of the graphite||LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2) pouch cell is remarkably improved under all-climate condition.