(JP6096615-A)      Polymeric electrolyte is produced by crosslinking a terminally-modified polyalkylene oxide of formula (I) and/or (II), where Z is residue of active-H-contg. cpd.; R2 is H, alkyl or Ph; k is 1-12; m is 1-240; p is 1-220; and R1 is a gp. of formula (II): n is 0 or 1-25; and R is 1-20C alkyl, alkenyl, aryl or alkylaryl; having a mean mol.wt. 500-50000 to produce an organic polymer, and introducing a soluble electrolyte salt into the polymer, the terminal gps. Y being partly alkyl, alkenyl or aryl, with the remainder being polymerisable functional gps. R2 is pref. H or Me.    Pref. polymerisable functional gps. are (meth)acryloyl or allyl; alkyl, alkenyl or aryl Y gps. pref. comprise 50-98%, the polymerisable functional gps. Y comprising 2-50%. The polymer is pref. prepd. by irradiation with heat, light or electrons beam, in the presence of initiator or sensitiser, if necessary.    USE/ADVANTAGE -   Used in batteries operating under high load, e.g. in electrically-powered vehicles. Have high ionic conductivities and are useable in large batteries at high operating temps.    (US5433877-A)      Ion-conductive polymer electrolyte is produced by (a) crosslinking a terminal-modified polyalkylene oxide of formula Z-(-(-CH2-CH(R2)-O-)m-Y)k and having a mean mol. wt. of 500-50000 to produce an organic polymer; and (b) introducing a soluble electrolytic salt cpd. in the organic polymer where at least some, but not all, of the terminal Y are alkyl and the remainder are (meth)acryloyl; Z is the residue of an active H-contg. cpd.; R2 is H, alkyl or Ph; k is 3-12; and m is 1-240. Pref. R2 is H or CH3. Y comprises 50-98 wt.% alkyl and 2-50 wt.% polymerisable function.    USE/ADVANTAGE -   In large-sized batteries operating at high temps. High ionic conductivities. Safe for a variety of practical applications.    (EP585072-B1)       Polymeric electrolyte is produced by crosslinking a terminally-modified polyalkylene oxide of formula Z-((CH2 CH(R2 )O)m Y))k (I) and/or Z-((R1 )p (CH2 CH(R2 )O)m Y)k (II): Z is residue of active-H-contg. cpd.; R2 is H, alkyl or Ph; k is 1-12; m is 1-240; p is 1-220; and R1 is a gp. of formula -(CH2 CH(CH2 O(CH2 CH2 CH2 O)nR)O)- (III): n is 0 or 1-25; and R is 1-20C alkyl, alkenyl, aryl or alkylaryl; having a mean mol.wt. 500-50000 to produce an organic polymer, and introducing a soluble electrolyte salt into the polymer, the terminal gps. Y being partly alkyl, alkenyl or aryl, with the remainder being polymerisable functional gps. R2 is pref. H or Me.    Pref., polymerisable functional gps. are (meth)acryloyl or allyl; alkyl, alkenyl or aryl Y gps. pref. comprise 50-98%, the polymerisable functional gps. Y comprising 2-50%. The polymer is pref. prepd. by irradiation with heat, light or electrons beam, in the presence of initiator or sensitiser, if necessary.    USE/ADVANTAGE -   In batteries operating under high load, e.g. in electrically-powered vehicles. Have high ionic conductivities and are useable in large batteries at high operating temps.