(WO9415376-A1)      A solid conductive electrolyte compsn. comprises a polyhydroxy alkanoate polymer and a salt of a conductive metal. The polyhydroxy alkanoate has repeating units of the formula (I). R is 1-10C alkyl or alkenyl, and has molecular wt. 10000-1000000. The mole ratio of polymer to salt is 5-20:1.    USE/ADVANTAGE -   The electrolyte compsn. is used between an anode and cathode in batteries. The polyhydroxy alkanoate is biodegradable and biocompatible, providing a basis for batteries which are more environmentally degradable. The polyhydroxy alkanoate can be naturally occurring.    (JP7504297-W)      A solid conductive electrolyte compsn. comprises a polyhydroxyalkanoate polymer and a salt of a conductive metal. The polyhydroxyalkanoate has repeating units of the formula (I). R is 1-10C alkyl or alkenyl, and has molecular wt. 10000-1000000. The mole ratio of polymer to salt is 5-20:1.    USE/ADVANTAGE -   The electrolyte compsn. is used between an anode and cathode in batteries. The polyhydroxyalkanoate is biodegradable and biocompatible, providing a basis for batteries which are more environmentally degradable. The polyhydroxyalkanoate can be naturally occurring.    (JP2752257-B2)      A solid conductive electrolyte compsn. comprises a polyhydroxyalkanoate polymer and a salt of a conductive metal. The polyhydroxyalkanoate has repeating units of the formula (I). R is 1-10C alkyl or alkenyl, and has molecular wt. 10000-1000000. The mole ratio of polymer to salt is 5-20:1.    USE/ADVANTAGE -   The electrolyte compsn. is used between an anode and cathode in batteries. The polyhydroxyalkanoate is biodegradable and biocompatible, providing a basis for batteries which are more environmentally degradable. The polyhydroxyalkanoate can be naturally occurring.    (EP636279-B1)      A solid conductive electrolyte compsn. comprises a polyhydroxyalkanoate polymer and a salt of a conductive metal. The polyhydroxyalkanoate has repeating units of the formula (I). R is 1-10C alkyl or alkenyl, and has molecular wt. 10000-1000000. The mole ratio of polymer to salt is 5-20:1.    USE/ADVANTAGE -   The electrolyte compsn. is used between an anode and cathode in batteries. The polyhydroxyalkanoate is biodegradable and biocompatible, providing a basis for batteries which are more environmentally degradable. The polyhydroxyalkanoate can be naturally occurring.