This　work　concerns　the　melting　performance　enhancement　in　a　finned　shell　and　tube　thermal　energy　storage　device　containing　salt　based　phase　change　materials.　Two　storage　materials　of　a　pure　nitrate　salt　and　a　nitrate　salt　based　composite　that　made　of　nitrate　salt,　vermiculite　and　graphite　were　employed　and　comparatively　investigated.　A　two-dimensional　mathematical　model　was　established　to　predict　the　heat　transfer　occurred　in　the　salts　by　considering　the　combined　impacts　of　natural　convection　and　thermal　conduction.　A　set　of　simulation　data　from　literature　was　used　to　verify　the　modelling　code　for　the　pure　salt　and　an　experiment　was　built　to　validate　the　numerical　model　for　the　salt　composite.　The　effects　of　fin　amount,　arrangement,　length　and　thickness　as　well　as　operating　condition　on　the　device　melting　behaviour　were　detailedly　eval-uated.　The　results　indicated　the　benefit　of　employment　fins　in　accelerating　the　salt　melting　rate.　The　use　of　salt　based　composite　combined　with　enhanced　fins　led　to　a　more　remarkable　improvement　on　the　device　melting　process,　and　the　adjustment　of　fin　length　and　thickness　as　well　as　composite　ingredients　composition　achieved　further　intensification.　For　a　given　fin　amounts　over　0-8　with　the　same　neighbour　angle,　the　melting　process　in　the　device　containing　salt　composite　is　respectively　shortened　around　79%　and　56%　compared　to　the　device　containing　pure　salt,　indicating　the　utilization　of　composite　is　a　better　choice　than　the　pure　salt　for　the　performance　enhancement　in　finned　shell　and　tube　thermal　energy　storage　device.