Ge-based　materials　have　garnered　much　attention　in　lithium-ion　batteries　(LIBs)　for　their　high　theoretical　capacity,　but　these　materials　suffer　from　huge　volume　changes　and　serious　pulverization,　which　cause　insufficient　lithium　storage　performance.　Herein,　a　composite　composed　of　Co5Ge3-and　nitrogen-doped　carbon　nanotube　(Co5Ge3/N-CNT)　was　successfully　synthesized　using　ZIF-67　and　GeO2　as　precursors.　There　are　interactions　between　the　Co5Ge3　alloy　nanoparticles　and　carbon　nanotubes　in　the　growth　process,　in　which　the　Co5Ge3　alloy　nanoparticles　were　confined　in　situ　in　N-CNTs　and　the　in　situ　growth　of　N-CNTs　was　boosted　in　the　existence　of　the　Co5Ge3　catalyst.　Density　functional　theory　calculations　revealed　that　the　electronic　conductivity　of　the　Co5Ge3　alloy　is　much　higher　than　that　of　Ge　and　the　Li+　interaction　energy　of　the　former　is　lower　than　that　of　the　latter.　In　addition,　the　interconnected　carbon　nanotubes　not　only　offer　Li+　diffusion　pathways　and　electronic　networks　but　also　increase　electronic　conductivity.　Importantly,　carbon　nanotubes　and　Co　metal　have　a　synergistic　effect　of　buffering　volume　charge　of　Ge　in　the　process　of　Li+　intercalation/deintercalation.　As　expected,　the　Co5Ge3/N-CNT　composite　demonstrated　a　high　reversible　capacity　of　853.7　mA　h　g-1　at　2　A　g-1　after　1500　cycles　and　attractive　rate　performance　of　up　to　10　A　g-1.　Copyright　©　2020　American　Chemical　Society.