Equivalent　circuit　model　(ECM)　is　a　common　method　to　simulate　the　electrochemical　characteristics　of　lithium-ion　batteries　(LIBs).　Fractional　order　model　(FOM)　has　been　proved　to　be　able　to　characterize　the　internal　characteristics　of　the　battery　more　accurately,　and　the　identification　of　model　parameters　is　an　important　prerequisite　to　construct　the　ECM　of　LIBs.　In　this　paper,　a　model　parameter　identification　algorithm　based　on　Beetle　Antennae　Search-Recursive　Least　Squares　(BAS-RLS)　is　proposed　for　the　FOM　of　LIBs.　Firstly,　the　open　circuit　voltage　(OCV)　of　battery　is　identified　by　Rint　model.　After　obtaining　the　OCV　of　the　battery,　the　BAS-RLS　algorithm　is　used　to　identify　the　parameters　of　the　FOM.　The　verification　of　four　working　conditions　of　LIBs　confirms　that　the　constructed　FOM　has　higher　accuracy.　The　maximum　RMSE　and　MAE　of　the　model　output　terminal　voltage　indexes　under　four　working　conditions　are　9.1783　mv　and　7.0939　mv　respectively.　©　2023　IEEE.