Fibre batteries embracing wearable electronics.

The International Union of Pure and Applied Chemistry(IUPAC)released"fibre batteries"as one of the"2022 IUPAC Top Ten Emerging Technologies in the Field of Chemistry"on November 2022.Differing from conventional batteries that are generally bulky and rigid with poor wearability,fibre batteries are promising in wearable applications owing to the attractive features of being flexible and twistable,and can be woven into breathable fabrics to power various wearable devices[1-3].Remarkable progresses on fibre batteries have been achieved in the past decade,including battery chemistry,electrochemical performance,and functional-ization/integration[4,5].However,the large-scale production and application of fibre batteries have been long hindered by the fol-lowing challenges,i.e.,severely-limited device lengths(several centimeters)[6]and low energy densities(＜1 Wh kg-1 based on the total device mass)[7],which hinders their real-world applica-tions.Therefore,the continuous production of long fibre batteries with excellent energy density,cycling stability and safety is con-sidered the"Holy Grail"of the whole field[6].