Absorption　energy　storage　(AES)　has　attracted　worldwide　attention　due　to　the　high　energy　storage　density　and　environmental　friendliness.　To　optimize　the　performance　of　the　AES　system,　a　finite　time　thermodynamic　(FTT)　model　considering　some　influencing　factors　such　as　time,　heat　transfer　area,　heat　transfer　temperature　difference,　internal　friction　and　dissipation　has　been　developed　in　this　paper.　A　new　concept　of　ratio　of　charging　and　discharging　time　is　proposed.　The　general　relation　of　the　energy　storage　efficiency,　energy　storage　rate　and　energy　release　rate　are　induced　based　on　FTT　analysis.　The　distribution　of　the　total　thermal　conductivity　was　optimized　under　the　condition　of　a　certain　total　thermal　conductivity　and　the　optimized　maximum　cooldown　release　rate　has　been　increased　by　14%.　The　optimal　operating　conditions　of　the　AES　system　are　obtained.　Furthermore,　the　influences　of　the　internal　irreversibility,　ratio　of　charging　and　discharging　time　and　heat　source　temperatures　on　the　performance　of　the　AES　system　are　analyzed.　The　research　results　can　provide　theoretical　basis　and　guidance　for　the　AES　system　design　and　optimization.　©　2023　Elsevier　Ltd