Latent　heat　thermal　energy　storage　(LHTES)　is　crucial　in　the　application　of　renewable　energy　and　waste　heat　recovery.　A　novel　LHTES　device　with　a　flat　micro-heat　pipe　array　(FMHPA)-metal　foam　composite　structure　is　designed　in　this　study　to　obtain　excellent　heat　transfer　performance.　An　evaluation　standard　called　integrated　power　is　proposed　to　assess　and　compare　the　structural　advantages　of　the　LHTES　device　with　others.　Performances　of　FMHPA,　temperature　distribution,　effort　of　inlet　temperature　and　velocity　of　heat　transfer　fluid　(HTF)　are　also　studied　in　the　experiments.　A　three-dimensional　numerical　model　is　developed　to　investigate　the　effort　of　porosity　and　pore　density　of　metal　foam　on　the　charging　process.　Results　show　that　the　FMHPA-copper　foam　composite　structure　improves　the　performance　of　the　LHTES　device.　This　structure　exhibits　stronger　heat　transfer　performance　than　that　of　other　devices.　The　increasing　inlet　temperature　of　HTF　has　a　better　promotion　effect　on　power　than　raising　HTF　velocity.　High　porosity　is　conducive　to　natural　convection　but　detrimental　to　heat　conduction.　High　pore　density　is　disadvantageous　to　natural　convection　and　does　not　affect　heat　conduction.　(C)　2020　Elsevier　Ltd.　All　rights　reserved.