Poly(thiourea triethylene glycol) as a multifunctional binder for enhanced performance in lithium-sulfur batteries

A mechanically strong binder with polar functional groups could overcome the dilemma of large volume change during charge/discharge processes and poor cyclability lithium-sulfur batteries (LSBs). In this work, for first time, we report use poly(thiourea triethylene glycol) (PTTG) as a multifunctional sulfur cathodes to enhance performance LSBs. As expected, PTTG facilitates high stability delivered by Sulfur-PTTG cathode, including higher reversible capacity 825 mAh g?1 at 0.2 C after 80 cycles, lower fading (0.123% per cycle) over 350 cycles 0.5 C, areal 2.5 cm?2 0.25 mA cm?2, better rate capability 587 2 C. Such superior electrochemical performances be attributed PTTG's chemical adsorption towards polysulfides which may avoid lithium polysulfide shuttle effect excellent mechanical characteristics prevents electrode collapse cycling allows maintain robust electron ion migration pathways accelerated redox reaction kinetics.