Urchin-shaped　NiCo2Se4　(u-NCSe)　nanostructures　as　efficient　sulfur　hosts　are　synthesized　to　overcome　the　limitations　of　lithium–sulfur　batteries　(LSBs).　u-NCSe　provides　a　beneficial　hollow　structure　to　relieve　volumetric　expansion,　a　superior　electrical　conductivity　to　improve　electron　transfer,　a　high　polarity　to　promote　absorption　of　lithium　polysulfides　(LiPS),　and　outstanding　electrocatalytic　activity　to　accelerate　LiPS　conversion　kinetics.　Owing　to　these　excellent　qualities　as　cathode　for　LSBs,　S@u-NCSe　delivers　outstanding　initial　capacities　up　to　1403　mAh　g−1　at　0.1　C　and　retains　626　mAh　g−1　at　5　C　with　exceptional　rate　performance.　More　significantly,　a　very　low　capacity　decay　rate　of　only　0.016%　per　cycle　is　obtained　after　2000　cycles　at　3　C.　Even　at　high　sulfur　loading　(3.2　mg　cm−2),　a　reversible　capacity　of　557　mAh　g−1　is　delivered　after　600　cycles　at　1　C.　Density　functional　theory　calculations　further　confirm　the　strong　interaction　between　NCSe　and　LiPS,　and　cytotoxicity　measurements　prove　the　biocompatibility　of　NCSe.　This　work　not　only　demonstrates　that　transition　metal　selenides　can　be　promising　candidates　as　sulfur　host　materials,　but　also　provides　a　strategy　for　the　rational　design　and　the　development　of　LSBs　with　long-life　and　high-rate　electrochemical　performance.　©　2019　WILEY-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim