The　sluggish　conversion　kinetics　of　the　lithium　polysulfide　(LiPS)　intermediates　are　hindering　the　practical　application　of　lithium　sulfur　batteries　(LSB)　by　their　low　efficiency　and　low　cycle　stability.　To　tackle　these　challenges,　a　rapid　internal　conversion　(RIC)　mechanism　is　proposed　for　the　first　time　to　accelerate　the　liquid-solid　conversion　in　the　sulfur　reduction　reaction　(SRR)　kinetics.　It　is　reaveled　that　the　reaction　energy　barrier　in　the　SRR　lies　in　the　liquid-solid　conversion,　from　Li2S4　to　LiS2*　to　Li2S2.　To　accelerate　the　liquid-solid　conversion,　the　CoS2@MoS2　hollow　nanocage,　a　novel　sulfur　cathode,　with　the　rational　synergistic　active　site　configuration　is　specifically　designed　toward　a　well-managed　reaction　path　and　sulfurphilic　structure　to　regulate　and　modulate　Li　(LiPS)-S(sulfide)　and　S(LiPS)-M(sulfide)　bonds　prominently,　affecting　on　activating　reactants　and　stablizing　transition　states.　Based　on　the　RIC　mechanism　in　the　SRR,　the　stronger　S-Co　bonds　between　CoS2　and　LiPS　traps　Li2S4　and　catalytically　facilitates　S-S　bond　scission　while　the　MoS2　is　conducive　to　the　migration　of　Li2S4　by　weaker　Li-S　bonds.　The　unique　synergetic　conversion　and　catalytic　functions　is　confirmed　by　density　functional　theory　(DFT)　calculations.　The　RIC　mechanism　could　provide　a　new　idea　for　exploring　the　conversion-catalysis　material　of　Li-S　batteries　in　the　specific　material　design.