(JP9073907-A)      A solid polymer electrolyte comprises a composite of (a) (i) a polymer obtd. from cpd(s). contg. a structure derived from a polyhydric alcohol (I) having 3 OH; and/or (ii) a copolymer comprising above cpd(s). as comonomer(s); and (b) electrolyte salt(s). In (I), 2 H of alcoholic OH are replaced by a unit of formula: CH2=C(R1)C(=O)(O(CH2)x(CH(CH3))y)2NHC(=O)OR2- (i) (where R1 = H or CH3; and R2 = divalent organic contg. oxyalkylene(s) and opt. other atoms than C, H or O; x and y = 0-5; z = 0-10; and units of (CH2) and (CH(CH3)) may be arranged irregularly).    Also claimed are (i) a battery; (ii) a process for mfg. the battery; (iii) an electrode; (iv) an electric double layer capacitor; and (v) a process for mfg. the capacitor.    USE -   Electrolyte is used for mfg. thin electrodes, batteries and electric double layer capacitors (all claimed) and can be moulded into a free-standing film of &lt; 50 thickness, a plate or a disk. Batteries can be used as power source for electric prods. e.g. portable device, as back-up power source or large capacity source for electric vehicles etc.    ADVANTAGE -   Electrolyte has good film strength, processability and high ionic conductivity. Mfd. prods. are free from leakage of any soln. High ionic conductivity is maintained at room temp. and lower. Batteries can operate at high capacity and high voltage, and have high electrochemical activity and flexibility; good polarisability, strength and contractability. Battery is highly reliable with large take-out current.    (EP811029-A1)      A solid polymer electrolyte comprises a composite of (a) (i) a polymer obtd. from cpd(s). contg. a structure derived from a polyhydric alcohol (I) having 3 OH; and/or (ii) a copolymer comprising above cpd(s). as comonomer(s); and (b) electrolyte salt(s). In (I), 2 H of alcoholic OH are replaced by a unit of formula: CH2=C(R1)C(=O)(O(CH2)x(CH(CH3))y)2NHC(=O)OR2- (i) (where R1 = H or CH3; and R2 = divalent organic contg. oxyalkylene(s) and opt. other atoms than C, H or O; x and y = 0-5; z = 0-10; and units of (CH2) and (CH(CH3)) may be arranged irregularly).    Also claimed are (i) a battery; (ii) a process for mfg. the battery; (iii) an electrode; (iv) an electric double layer capacitor; and (v) a process for mfg. the capacitor.    USE -   Electrolyte is used for mfg. thin electrodes, batteries and electric double layer capacitors (all claimed) and can be moulded into a free-standing film of &lt; 50 thickness, a plate or a disk. Batteries can be used as power source for electric prods. e.g. portable device, as back-up power source or large capacity source for electric vehicles etc.    ADVANTAGE -   Electrolyte has good film strength, processability and high ionic conductivity. Mfd. prods. are free from leakage of any soln. High ionic conductivity is maintained at room temp. and lower. Batteries can operate at high capacity and high voltage, and have high electrochemical activity and flexibility; good polarisability, strength and contractability. Battery is highly reliable with large take-out current.    (US5874184-A)      A solid polymer electrolyte comprises a composite of (a) (i) a polymer obtd. from cpd(s). contg. a structure derived from a polyhydric alcohol (I) having 3 OH; and/or (ii) a copolymer comprising above cpd(s). as comonomer(s); and (b) electrolyte salt(s). In (I), 2 H of alcoholic OH are replaced by a unit of formula: CH2=C(R1)C(=O)(O(CH2)x(CH(CH3))y)2NHC(=O)OR2- (i) (where R1 = H or CH3; and R2 = divalent organic contg. oxyalkylene(s) and opt. other atoms than C, H or O; x and y = 0-5; z = 0-10; and units of (CH2) and (CH(CH3)) may be arranged irregularly).    Also claimed are (i) a battery; (ii) a process for mfg. the battery; (iii) an electrode; (iv) an electric double layer capacitor; and (v) a process for mfg. the capacitor.    USE -   Electrolyte is used for mfg. thin electrodes, batteries and electric double layer capacitors (all claimed) and can be moulded into a free-standing film of &lt; 50 thickness, a plate or a disk. Batteries can be used as power source for electric prods. e.g. portable device, as back-up power source or large capacity source for electric vehicles etc.    ADVANTAGE -   Electrolyte has good film strength, processability and high ionic conductivity. Mfd. prods. are free from leakage of any soln. High ionic conductivity is maintained at room temp. and lower. Batteries can operate at high capacity and high voltage, and have high electrochemical activity and flexibility; good polarisability, strength and contractability. Battery is highly reliable with large take-out current.    (EP811029-B1)      A solid polymer electrolyte comprises a composite of (a) (i) a polymer obtd. from cpd(s). contg. a structure derived from a polyhydric alcohol (I) having 3 OH; and/or (ii) a copolymer comprising above cpd(s). as comonomer(s); and (b) electrolyte salt(s). In (I), 2 H of alcoholic OH are replaced by a unit of formula: CH2=C(R1)C(=O)(O(CH2)x(CH(CH3))y)2NHC(=O)OR2- (i) (where R1 = H or CH3; and R2 = divalent organic contg. oxyalkylene(s) and opt. other atoms than C, H or O; x and y = 0-5; z = 0-10; and units of (CH2) and (CH(CH3)) may be arranged irregularly).    Also claimed are (i) a battery; (ii) a process for mfg. the battery; (iii) an electrode; (iv) an electric double layer capacitor; and (v) a process for mfg. the capacitor.    USE -   Electrolyte is used for mfg. thin electrodes, batteries and electric double layer capacitors (all claimed) and can be moulded into a free-standing film of &lt; 50 thickness, a plate or a disk. Batteries can be used as power source for electric prods. e.g. portable device, as back-up power source or large capacity source for electric vehicles etc.    ADVANTAGE -   Electrolyte has good film strength, processability and high ionic conductivity. Mfd. prods. are free from leakage of any soln. High ionic conductivity is maintained at room temp. and lower. Batteries can operate at high capacity and high voltage, and have high electrochemical activity and flexibility; good polarisability, strength and contractability. Battery is highly reliable with large take-out current.    (JP3129961-B2)      A solid polymer electrolyte comprises a composite of (a) (i) a polymer obtd. from cpd(s). contg. a structure derived from a polyhydric alcohol (I) having 3 OH; and/or (ii) a copolymer comprising above cpd(s). as comonomer(s); and (b) electrolyte salt(s). In (I), 2 H of alcoholic OH are replaced by a unit of formula: CH2=C(R1)C(=O)(O(CH2)x(CH(CH3))y)2NHC(=O)OR2- (i) (where R1 = H or CH3; and R2 = divalent organic contg. oxyalkylene(s) and opt. other atoms than C, H or O; x and y = 0-5; z = 0-10; and units of (CH2) and (CH(CH3)) may be arranged irregularly).    Also claimed are (i) a battery; (ii) a process for mfg. the battery; (iii) an electrode; (iv) an electric double layer capacitor; and (v) a process for mfg. the capacitor.    USE -   Electrolyte is used for mfg. thin electrodes, batteries and electric double layer capacitors (all claimed) and can be moulded into a free-standing film of &lt; 50 thickness, a plate or a disk. Batteries can be used as power source for electric prods. e.g. portable device, as back-up power source or large capacity source for electric vehicles etc.    ADVANTAGE -   Electrolyte has good film strength, processability and high ionic conductivity. Mfd. prods. are free from leakage of any soln. High ionic conductivity is maintained at room temp. and lower. Batteries can operate at high capacity and high voltage, and have high electrochemical activity and flexibility; good polarisability, strength and contractability. Battery is highly reliable with large take-out current.