No abstract

Lithium–sulfur batteries (LSBs) hold great promise as one of the next‐generation power supplies for portable electronics and electric vehicles due to their ultrahigh energy density, cost effectiveness, and environmental benignity. However, their practical application has been impeded owing to the electronic insulation of sulfur and its intermediates, serious shuttle effect, large volume variation, and uncontrollable formation of lithium dendrites. Over the past decades, many pioneering strategies have been developed to address these issues via improving electrodes, electrolytes, separators and binders. Remarkably, polymers can be readily applied to all these aspects due to their structural designability, functional versatility, superior chemical stability and processability. Moreover, their lightweight and rich resource characteristics enable the production of LSBs with high‐volume energy density at low cost. Surprisingly, there have been few reviews on development of polymers in LSBs. Herein, breakthroughs and future perspectives of emerging polymers in LSBs are scrutinized. Significant attention is centered on recent implementation of polymers in each component of LSBs with an emphasis on intrinsic mechanisms underlying their specific functions. The review offers a comprehensive overview of state‐of‐the‐art polymers for LSBs, provides in‐depth insights into addressing key challenges, and affords important resources for researchers working on electrochemical energy systems.

Redox-active conjugated polymers are the promising alternatives to inorganic electrode materials, whereas such organic electrodes usually suffer from low practical capacity, poor conductivity, high cost, and industrial incompatibility. Many commercial...

To enable large capacity and high rate capability of porous carbon electrodes for lithium-ion batteries (LIBs) and supercapacitors, the combination of doping active heteroatoms, tailoring pore architectures, and narrowing pore sizes is a powerful engineered strategy. However, such porous carbons with multiple synergistic effects are almost impossible to be achieved simultaneously by conventional synthesis methods in a few steps. Herein, two mechanistically coupled polymers of poly(2thiophenemethanol) (PThM) and SiO 2 in one step process were synchronically produced by twin-polymerization of a single-source hybrid monomer of tetrathenyloxysilane consisting of tetraethyl orthosilicate (TEOS) and ThM moieties. The resultant interpenetrated SiO 2 /PThM composites were then subjected to thermal annealing and subsequent etching, yielding a mesopore-dominant S-doped porous carbon (SPC-1) with large-micropores (1.3−2.0 nm), narrow pore distribution (1.3−4.1 nm, centered at 3.1 nm), rich S heteroatoms (>5%), and high specific surface area (792 m 2 /g). Remarkably, the symmetric supercapacitor based on SPC-1 delivers a specific capacitance of 420 F/g at 0.5 A/g and an energy density as high as 14.6 W h/ kg at the power density of 125 W/kg. As an anode for LIBs, SPC-1 delivers large reversible capacity (571 mAh/g), high rate capability, and excellent cyclic stability (without capacity decay after 500 cycles). More importantly, SPC-1 shows better electrochemical performance compared to a large mesopore (6−30 nm)-dominant S-doped porous carbon (SPC-2) derived by simultaneous polymerization of TEOS and ThM. This work reports an unusual in situ templating approach capable of synergistically combining chemical doping and pore engineering of carbonaceous materials for high-performance supercapacitors and LIBs.