A sulfur-linked carbonyl-based poly(2,5-dihydroxyl-1,4-benzoquinonyl sulfide) (PDHBQS) compound is synthesized and used as cathode material for lithium-ion batteries (LIBs). Flexible binder-free composite cathode with single-wall carbon nanotubes (PDHBQS-SWCNTs) is then fabricated through vacuum filtration method with SWCNTs. Electrochemical measurements show that PDHBQS-SWCNTs cathode can deliver a discharge capacity of 182 mA h g (0.9 mA h cm ) at a current rate of 50 mA g and a potential window of 1.5 V-3.5 V. The cathode delivers a capacity of 75 mA h g (0.47 mA h cm ) at 5000 mA g , which confirms its good rate performance at high current density. PDHBQS-SWCNTs flexible cathode retains 89% of its initial capacity at 250 mA g after 500 charge-discharge cycles. Furthermore, large-area (28 cm ) flexible batteries based on PDHBQS-SWCNTs cathode and lithium foils anode are also assembled. The flexible battery shows good electrochemical activities with continuous bending, which retains 88% of its initial discharge capacity after 2000 bending cycles. The significant capacity, high rate performance, superior cyclic performance, and good flexibility make this material a promising candidate for a future application of flexible LIBs.

Owing to the increasing pressure on the ecological effect of solid waste disposal and developing the need for disposal of the corresponding hazardous metals, recovery of spent lithium ion batteries (LIBs) has gain worldwide attention in recent years. Much work has been done in this regard in the past few decades, and several new, interesting, and unique methods have been developed to recycle the cathode, anode, and electrolyte. Therefore, time has come to summarize the highlights in this emerging area to facilitate young researchers. In this review, starting from the current market demand and commercial value of lithium ion batteries, we have summarized the most recent progress in the direction of recycling the cathode and anode materials and electrolyte. At the beginning, an overview of the recycling techniques is presented to grasp understanding of the topic. Later, laboratory and industrial investigations and implementation are reviewed with emphasis on anode (graphite) and electrolyte recovery. Life cycle assessment of end-of-life LIB recycling, limitations, and future efforts have also mentioned to focus on improving the efficiency of metal extraction and separation with the sustainable and systematic recycling of spent lithium ion batteries.

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Advancement in mobile electronics is driving progress in lithium ion batteries. Recently, organic electrode materials have emerged as promising candidates for lithium ion batteries due to their high theoretical capacity, ease of synthesis, versatility of structure, and abundance. Polymerization is a strategy used to overcome the issues associated with small organic molecules for charge storage application. The focus of this review is on the most recent progress in the field of polymeric carbonyl materials for lithium ion batteries (LIBs) and sodium ion batteries (SIBs). Advantages of organic electrode materials, device architecture, and charge storage mechanism are discussed. Challenges associated with carbonyl‐based electrodes and some recent solutions are outlined. Later, a comparison of theoretical capacity, practical capacity, and cyclic life are presented for different carbonyl systems. Capacity‐fading phenomena and structural degradation during charging are discussed where necessary. Some key parameters for the design of flexible batteries are highlighted and an overview of some recent contributions of our group in this field are reported. Finally, some future prospects for researchers in this field are outlined.

This review presents the recent developments in the research hotspots of advanced functional polymers; their concepts, design strategies, and applications are briefly discussed.

Despite the fact that lithium–sulfur batteries are regarded as promising next-generation rechargeable battery systems owning to high theoretical specific capacity (1675 mA h g–1) and energy density (2600 W h kg–1), several issues such as poor electrical conductivity, sluggish redox kinetics, and severe “shuttle effect” in electrodes still hinder their practical application. MXenes, novel two-dimensional materials with high conductivity, regulable interlayer spacing, and abundant functional groups, are widely applied in energy storage and conversion fields. In this work, a Ti3C2/carbon hybrid with expanded interlayer spacing is synthesized by one-step heat treatment in molten potassium hydroxide. The subsequent experiments indicate that the as-prepared Ti3C2/carbon hybrid can effectively regulate polysulfide redox conversion and has strong chemisorption interaction to polysulfides. Consequently, the Ti3C2/carbon-based sulfur cathode boosts the performance in working lithium–sulfur batteries, in terms of an ultrahigh initial discharge capacity (1668 mA h g–1 at 0.1 C), an excellent rate performance (520 mA h g–1 at 5 C), and an outstanding capacity retention of 530 mA h g–1 after 500 cycles at 1 C with a low capacity fade rate of 0.05% per cycle and stable Coulombic efficiency (nearly 99%). The above results indicate that this composite with high catalytic activity is a potential host material for further high-performance lithium–sulfur batteries.

Lithium‐sulfur (Li‐S) batteries with high energy density are promising candidates for next‐generation energy storage systems. Practical application of Li‐S batteries is hindered by shuttle effect of polysulfides and Li dendrites growth. Herein, a self‐supporting cofunction host is constructed with 3D hierarchical graphene modified by N‐doped nanoarrays, for both Li anode and S cathode to improve their performances simultaneously. Attributed to high conductivity, strong affinity, and optimized Li‐ion transport pathway of N‐doped nanoarrays, cofunction host provide excellent Li and S load, which facilitates uniform Li deposition and enhanced S conversion. Particularly, an extra graphene barrier is specialized for S cathode to inhibit the shuttle effect. As a result, Li anode shows long cycle life with outstanding Li‐plating behavior, and S cathode shows high capacity and ultrahigh capacity retention with good immobilization of polysulfides. More importantly, the integrated Li‐S battery shows long cycle stability and good flexibility, which is important for future application.

Transfer of molecular chirality to supramolecular chirality at nanoscale and microscale by chemical self-assembly has been studied intensively for years. However, how such molecular chirality further transfers to the macroscale along the same path remains elusive. Here we reveal how the chirality from molecular level transfers to macroscopic level via self-assembly. We assemble a macrostripe using enantiomeric camphorsulfonic acid (CSA)-doped polyaniline with hierarchical order. The stripe can twist into a single-handed helical ribbon via helical self-motion. A multi-scale chemo-mechanical model is used to elucidate the mechanism underlying its chirality transfer and induction. The molecular origin of this macroscopic helical chirality is verified. Results provide a comprehensive understanding of hierarchical chirality transfer and helical motion in self-assembled materials and even their natural analogues. The stripe exhibits disparate actuation behaviour under stimuli of enantiomeric amines and integrating such chiral perception with helical self-motion may motivate chiral biomimetic studies of smart materials.