A new composite gel polymer electrolyte (PEO-Bp-LATP) membrane consisting of poly-ethylene oxide (PEO), benzophenone (Bp) and varying amounts of highly ion-conducting lithium aluminum titanium phosphate (LATP) particles was prepared by significant Ultraviolet (UV) technology. The as-prepared PEO-Bp-LATP electrolyte membranes showed improved mechanical properties and superior electrochemical performances in Lithium metal batteries (LMBs). Typically, PEO-Bp-15 wt% LATP showed highest ionic conductivity (s=3.3 x 10(-3) S. cm(-1)) at RT, a high Li-transference (t(Li+)=0.77) and wider electrochemical stability window (ESW) above 5 V as well as good mechanical strength (9.3 MPa). More significantly, the PEO-Bp-15 wt% LATP membrane has an excellent inhibitory effect on Li dendrite expansion in Li symmetric cells and presents a long term cyclic stability with current density of 2 mA/cm(2) over 1100 h for Li//PEO-Bp-15 wt% LATP //Li. Our results for the measurement of galvanostatic charge-discharge deliver fascinating rate performance at 0.1C. Hence, the present study demonstrates that the UV-irradiated PEO-Bp-LATP membrane can be a promising electrolyte to meet the requirements for the next-generation LMBs.