The　Liquid　Antimony　Anode–based　Solid　Oxide　Fuel　Cell　(LAA-SOFC)　represents　a　promising　energy　conversion　approach　for　generating　power　using　complex　fuels.　This　study　addresses　the　relationship　between　the　liquid–liquid　distribution　of　Sb-Sb2O3　and　the　corresponding　electrochemical　performance　of　LAA-SOFC.　A　2-D　axisymmetric　model　that　incorporates　the　two-phase　flow　of　Sb-Sb2O3,　alongside　the　electric　field　and　the　chemical/electrochemical　reactions　is　successfully　developed　to　explore　the　reaction　and　convection　characteristics　of　LAA　in　LAA-SOFC　under　gravitational　influence.　The　model　results　indicate　that　the　density　disparity　between　Sb　and　Sb2O3　can　drive　convection　and　stratification　with　Sb2O3　generation　fostering　continuous　convection　within　the　anode.　The　high　Peclet　number　suggests　that　the　convection　is　the　primary　transport　mechanism　in　the　anode.　The　limited　Sb2O3　reduction　results　in　its　accumulation　in　the　upper　layer,　diminishing　the　effective　reaction　area　and　leading　to　a　rapid　decline　in　discharge　voltage.　However,　the　ionic　conductivity　of　Sb2O3　at　the　Sb/Sb2O3　interface　can　facilitate　approximately　10–20%　of　the　reactions,　marginally　mitigating　the　increase　in　voltage　loss.　To　offset　Sb2O3　accumulation＇s　impact　on　the　electrochemical　reactions,　a　horizontal　tubular　LAA-SOFC　is　designed　and　constructed,　which　can　effectively　sustain　the　discharge　voltage　across　a　broad　Sb2O3　fraction　range　of　0–85%.　©　2024　Elsevier　Ltd