Cool　release　process　of　phase　change　material　(PCM)　includes　the　dissolution　process　of　the　PCM.　Experimental　research　on　the　cool　release　process　in　a　new　gas-hydrate　cool　storage　system　is　performed　in　this　paper.　In　the　system,　the　inner-heat　exchange/outer-crystallization　technology　and　the　integrated　condenser/evaporator　structure　design　were　adopted.　The　influences　of　different　proportions　of　calcium　hypochlorite　or　benzenesulfonic　acid　sodium　salt　on　the　dissolution　process　are　studied.　The　results　show　that　the　instantaneous　dissolution　rate　is　close　to　twice　as　the　corresponding　instantaneous　formation　rate　of　gas-hydrate,　and　the　cold　energy　release　rate,　i.e.　energy　release　per　unit　time,　is　obviously　higher　than　the　corresponding　cold　energy　storage　rate　at　different　conditions,　which　is　mainly　due　to　the　heat　transfer　temperature　difference　of　the　discharging　(release)　and　charging　(store)　processes.　Both　the　charging　and　the　discharging　processes　are　simultaneously　dominated　by　the　heat　transfer　and　the　mass　transfer　processes.　However,　as　to　the　dissolution　(discharging)　process　of　the　gas-hydrate　by　heating,　the　effect　of　the　heat　transfer　process　is　the　main　influence　factor.　The　temperature　difference　between　the　heating　medium　and　the　gas-hydrate　in　the　discharging　process,　which　is　larger　than　that　between　the　cooling　medium　and　the　gas-hydrate　in　the　charging　process,　makes　a　higher　cold　energy　release　rate　compared　with　the　cold　energy　storage　rate.　The　results　also　indicate　that　the　dissolution　rate　of　gas-hydrate　is　accelerated,　and　the　cold　energy　release　rate　of　the　cool　storage　system　is　increased　by　adding　reasonable　proportions　of　the　additives.　(C)　2008　Elsevier　B.V.　All　rights　reserved.