Light-emitting　electrochemical　cells　(LECs)　have　the　advantages　of　simple　structure,　low　driving　voltage,　and　low　packaging　requirements.　However,　due　to　the　different　mobility　of　electrons　and　holes　in　emission　layer,　exciton　quenching　is　inevitable　caused　by　carrier　imbalance.　In　this　work,　a　red　light　cationic　Ir()　complexes　[Ir(tBuPBI)2(qibi)]PF6　(R)　was　used　as　the　luminescent　materials　for　the　LECs,　and　we　use　the　doping　of　MoOx　into　poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)　layer　to　lower　the　energy　barrier　between　complexes　R　and　anode.　In　combination　with　the　introduction　of　Al/LiF　composite　cathode,　the　carrier　injection　efficiency　of　the　LECs　is　significantly　improved,　leading　to　the　enhanced　balance　of　carrier　injection.　In　particular,　high　electron　injection　efficiency　would　significantly　contribute　to　the　device　improvement　based　on　the　complexes　with　hole-preferred　transporting　characteristic.　With　enhanced　carrier　injection,　the　recombination　region　of　the　carrier　is　located　near　the　center　of　emission　layer,　and　the　exciton　quenching　near　the　electrode　will　be　significantly　alleviated.　The　maximum　external　quantum　efficiency　of　the　LEC　device　is　as　high　as　11.77%,　which　is　1.3　time　that　of　the　standard　device.　The　half-lifetime　of　the　device　is　690　min,　which　is　about　1.37　times　of　that　of　the　standard　device.　©　2021　Elsevier　B.V.