Wearable electronics require lightweight and flexible batteries, of which lithiumsulfur (Li-S) batteries are of great interest due to their high gravimetric energy density. Nevertheless, flexible Li-S batteries have unsatisfactory electrochemical performance owing to electrode fracture during repeated bending, the volume change of sulfur species and the severe shuttle effect. Binders play essential roles in these batteries but have always lacked attention. Herein, a self-healing polyvinylpyrrolidone-polyethyleneimine (PVP-PEI) binder cross-linked by hydrogen bonds, which also regulates polysulfide redox kinetics, is reported. The dynamic hydrogen-bonding networks repair the cracks and ensure the integrity of the electrode while numerous polar groups such as CO and -NH 2 suppress the shuttle effect by immobilizing polysulfides. Therefore, Li-S batteries with the PVP-PEI binder exhibit excellent cycling stability (a capacity decay rate of 0.0718% per cycle at 1 C after 450 cycles), an outstanding areal capacity of 7.67 mAh cm −2 even under a high sulfur loading (7.1 mg cm −2 ) and relatively lean electrolyte conditions (E/S ratio = 8 µL mg −1 ). Flexible Li-S pouch cells using the PVP-PEI binder show a stable performance for 140 cycles and a favorable capacity retention of over 95% after 2800 bending cycles, confirming its application potential in high-performance flexible Li-S batteries.

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Li metal is the ultimate choice for the anode in next-generation high energy density rechargeable batteries. However, undesired dendrite growth, dead Li formation, and a large volume change of the lithium metal anode lead to severe safety hazards such as short-circuiting, fire, or even explosion. Graphene oxide (GO) in large areas has been prepared as the Li metal host via a continuous centrifugal casting method. Aligned microchannels are then fabricated in it by a simple punching method using 3D printed templates. The GO matrix effectively regulates the lithium plating/stripping behavior while the aligned channels uniformly distributes the Li-ion flux and provides short Li-ion diffusion paths. The Li/ holey GO composite is flexible with a controllable thickness from 50 to 150 µm, which corresponds to capacities from 9.881 to 27.601 mAh cm −2 . As a result, the anode has a low overpotential of 30 mV after 100 h, a high capacity of ≈3538 mAh g −1 (91.4% of the theoretical capacity), and a superior rate ability of up to 50 C with a LiFePO 4 cathode. The holey GO/Li electrode is also paired with other cathodes and used in pouch cells, indicating its suitability for various high-energy battery systems.