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Ether-free bis-piperidinium main-chain poly(ionic liquid)s are synthesized by a gentle and facile method, and high-performance AEMs are fabricated by blending poly(bis-piperidinium)s and polybenzimidazole. [Display omitted] • Seven ether-free bis-piperidinium main-chain poly(ionic liquid)s are synthesized by a gentle and facile method. • New blend AEMs based on poly(bis-alkyl piperidinium)s and PBI are fabricated. • The Pip-C 4 /PBI membrane displays high performance and superior alkaline stability. Anion exchange membranes (AEMs) play a critical role in various environmentally friendly electrochemical energy conversion and storage devices such fuel cells, water electrolysis and flow batteries. Recently, AEMs based on ether-free ionomers or ionenes have attracted much attention due to their excellent alkaline stabilities, however normally suffering from multiple-step synthetic procedure, post-functionalization and the use of precious metal catalysts. In this study, we develop a facile method to synthesize bis-piperidinium main-chain poly(ionic liquid)s devoid of ether linkages through the nucleophilic reaction between a bis-piperidine monomer of 4,4′-trimethylene bis(1-methyl-piperidine) and various bifunctional alkyl or aryl bromides. Seven poly(ionic liquid)s of poly(bis-alkyl piperidinium) are subsequently blended with polybenzimidazole (PBI) to give mechanically robust and dimensionally stable AEMs. The membrane performances are readily adjusted by changing the chemical structure of poly(bis-alkyl piperidinium)s. The membrane based on the poly(bis-alkyl piperidinium) containing a flexible butylidene spacer chain achieves the highest Br- conductivity of 67 mS cm−1 at 80 °C, tensile strength of around 13 MPa at room temperature, and a superior alkaline stability in 1 mol/L KOH at 60 °C during 1250 h. Density functional theory calculations further support the enhanced alkaline stability of the piperidinium cation with alkyl group compared with the one with benzyl group. [ABSTRACT FROM AUTHOR]