Lithium-ion　batteries,　the　heart　of　electric　vehicles　(EVs),　are　subject　to　capacity　attenuation　and　lithium　plating　at　low　temperatures,　which　is　essential　to　preheat　lithium-ion　batteries　at　low-temperature　ambient.　In　this　study,　a　battery　thermal　management　system　(BTMS)　was　established　to　achieve　integration　of　preheating　and　cooling　at　the　module　level　through　a　bent　flat　micro　heat　pipe　array　(FMHPA).　As　a　thermal　bridge,　the　bending　FMHPAs　realize　the　separation　of　the　coolant　and　the　battery,　non-interference　of　preheating　and　cooling,　and　small　space　occupation.　Heat　transfer　characteristics　of　bending　FMHPA,　preheating　performance　of　the　BTMS,　and　the　effect　of　insulation　shell　were　studied　experimentally.　Results　showed　that　the　effective　thermal　con-ductivity　of　Z-shape　bending　FMHPA　is　15,741　Wm-1K-1.　The　temperature　rise　rate　can　reach　about　1　degrees　C/min　at　the　ambient　temperatures　of-20,-10　and　0　degrees　C.　The　temperature　differences　at　both　cell　and　module　levels　are　kept　within　5　degrees　C.　The　insulation　shell　with　a　thickness　of　20　mm　can　increase　the　temperature　rise　rate　and　temperature　difference　at　module　level　by　41%　and　35%,　respectively,　but　with　no　obvious　influence　on　the　active　cooling　effect　at　high-temperature　ambient.