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The photo‐assisted strategy is regarded as a crucial approach to enhance the conversion kinetics of polysulfides in lithium–sulfur (Li–S) batteries. However, the development of photo‐assisted Li–S batteries still faces important challenges, such as the rapid recombination of photogenerated electron−holes on cathode and more severe shuttle effect. Herein, a breakthrough in overcoming the challenges has been made by constructing a promising photo‐assisted Li−S battery based on semiconducted metal−organic frameworks. During the discharging progress, the photoexcited electrons generated by H2BPDC ligand based on ligand‐to‐metal charge transfer (LMCT) effect, are injected into the Ti‐oxo clusters in Ti‐MOF, thereby facilitating the sulfur reduction to Li2S. And photoexcited holes are capable of promoting the decomposition kinetics of Li2S during charging. More importantly, the stronger chemical interaction between Ti‐BPDC‐d and polysulfides under light inhibits the polysulfides dissolution and shuttling, which fundamentally addresses the issue of light‐accelerated shuttling. As a result, the photo‐assisted Li–S batteries deliver a reversible capability of 1090.21 mAh g−1 at 0.2 C with a capacity retention of 82.91% over 150 cycles, and a superior rate capability of 673.58 mAh g−1 at 5 C. The findings are promising in advancing the design principles for photo‐rechargeable Li−S batteries. [ABSTRACT FROM AUTHOR]

The high overpotential caused by the slow kinetics of oxygen reduction (ORR) and oxygen evolution (OER) has greatly limited the practical application of lithium‐oxygen (Li−O2) batteries. The adoption of force‐field‐assisted system based on a newly developed piezocatalysis is promising in reducing the overpotential. Herein, a force‐assisted Li−O2 battery is first established by employing MoS2/Pd nanocomposite cathode, in which the piezoelectric polarization as well as built‐in electric field are formed in MoS2 piezoelectric catalyst under ultrasound activation, leading to the continuously separated electrons and holes to enhance the ORR and OER kinetics. Moreover, the introduction of Pd can promote the electrons transfer and further inhibit the complexation of electron–hole pairs, contributing to enhanced catalytic activity in the decomposition/generation of discharge products, resulting in reduced discharge/charge overpotentials. Thus, the force‐assisted MoS2/Pd‐based Li−O2 battery is capable of adjusting the output and input energies by the assisted ultrasonic wave. An ultra‐low charging platform of 2.86 V and a high discharging platform of 2.77 V are achieved. The proposed unique force‐assisted strategy can also be applied to lithium carbon dioxide battery system through the effective reduction and separation of CO2 and CO32−, providing significant insights in achieving efficient energy conversion for metal−air batteries. [ABSTRACT FROM AUTHOR]

A photoinduced flexible Li‐CO2 battery with well‐designed, hierarchical porous, and free‐standing In2S3@CNT/SS (ICS) as a bifunctional photoelectrode to accelerate both the CO2 reduction and evolution reactions (CDRR and CDER) is presented. The photoinduced Li‐CO2 battery achieved a record‐high discharge voltage of 3.14 V, surpassing the thermodynamic limit of 2.80 V, and an ultra‐low charge voltage of 3.20 V, achieving a round trip efficiency of 98.1 %, which is the highest value ever reported (<80 %) so far. These excellent properties can be ascribed to the hierarchical porous and free‐standing structure of ICS, as well as the key role of photogenerated electrons and holes during discharging and charging processes. A mechanism is proposed for pre‐activating CO2 by reducing In3+ to In+ under light illumination. The mechanism of the bifunctional light‐assisted process provides insight into photoinduced Li‐CO2 batteries and contributes to resolving the major setbacks of the system. [ABSTRACT FROM AUTHOR]

A flexible and highly efficient air cathode is fabricated via a simple electro‐deposition approach. This cathode exhibits a series of considerable electrochemical performances, in particular a good cycling performance (more than 70 cycles with the capacity limited 1000 mA h g−1). Based on this flexible cathode, a Li–O2 battery with flexible properties is also assembled, which can power a commercial LED normally. [ABSTRACT FROM AUTHOR]

The pressing demand on the electronic vehicles with long driving range on a single charge has necessitated the development of next-generation high-energy-density batteries. Non-aqueous Li-O2 batteries have received rapidly growing attention due to their higher theoretical energy densities compared to those of state-of-the-art Li-ion batteries.To make them practical for commercial applications, many critical issues must be overcome, including low round-trip efficiency and poor cycling stability, which are intimately connected to the problems resulting from cathode degradation during cycling. Encouragingly, during the past years, much effort has been devoted to enhancing the stability of the cathode using a variety of strategies and these have effectively surmounted the challenges derived from cathode deteriorations,thus endowing Li-O2 batteries with significantly improved electrochemical performances. Here, a brief overview of the general development of Li-O2 battery is presented. Then, critical issues relevant to the cathode instability are discussed and remarkable achievements in enhancing the cathode stability are highlighted. Finally, perspectives towards the development of next generation highly stable cathode are also discussed. [ABSTRACT FROM AUTHOR]

The issue of cathode passivation during cycling resulting in rapid capacity fading and premature battery death is a major challenge that hinders the applications of lithium–oxygen (Li–O 2) batteries. Here, a facile strategy of introducing a functional separator based on flexible amination SiO 2 /TiO 2 inorganic woven film (STON WF) is proposed to suppress the cathode passivation problem. The by-products, i.e. HCOOLi, CH 3 COOLi and Li 2 CO 3 can be selectively adsorbed on the STON WF separator preferably compared with the cathode and further proved by the density functional theory (DFT) calculations. Thus, benefiting from the separator, the Li–O 2 cells with super P carbon and catalyst-free cathode show enhanced electrochemical performance (5645 mA h g−1 at a current density of 200 mA g−1), good rate capability (discharge voltage of 2.43 V at a current density of 1.5 A g−1) and especially superior cycle stability up to 268 cycles. These findings present a promising approach to prevent the premature battery death. • STON WF separator is utilized as by-products scavenger for first time. • The cathode passivation can be effectively alleviated with STON WF separator. • Li+ ion diffusion and the cycling performance for Li–O 2 batteries are improved. • Recyclable and low-cost STON WF is expected to be applied industrialization. [ABSTRACT FROM AUTHOR]