TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The solution has a hydroxide ion concentration of at least 0.2 (preferably at least 2, especially up to 14) moles/liter; and has a temperature of not greater than 70degreesC. The hydride compounds are present in an amount which affords a total concentration of at least 2 (preferably at least 5, especially at least 7) moles per liter of colloidal dispersion. At least two hydride compounds are present; and are added successively to the solution. The solubility of a first hydride compound of the at least two hydride compounds in the solution is higher than a solubility of a second hydride compound of the at least two hydride compounds and where at least a part of the first hydride compound is added to the solution before the second hydride compound is added to it. The hydride compounds are capable of at least one of undergoing anodic oxidation in a liquid fuel cell and undergoing decomposition with generation of hydrogen gas under conditions which promote their hydrolysis. The hydride compounds are ammonium, alkali and alkaline earth metal hydrides, borohydrides and aluminum hydrides selected from NaBH4, KBH4, LiBH4, NH4BH4, Be(BH4)2, Ca(BH4)2, Mg(BH4)2, Zn(BH4)2, Al(BH4)3, a polyborohydride, (CH3)2NHBH3, NaCNBH3, LiH, NaH, KH, CaH2, BeH2, MgH2, NaAlH4, LiAlH4 or KAlH4; or at least one of NaBH4, KBH4, LiBH4, NH4BH4 or a polyborohydride of formula MB3H8, M2B10H10, MB10H13, M2B12H12 or M2B20H18 (preferably at least one of NaBH4 and KBH4).M=Li, Na, K, NH4, Be\2, Ca\2, Mg\2, Zn\2 or Al1/3.The hydroxide ion providing compounds are selected from hydroxides of alkali and alkaline earth metals, Zn and Al and from ammonium hydroxide; and comprise at least one of LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Mg(OH)2, Ba(OH)2, Zn(OH)2, Al(OH)3 and NH4OH (preferably at least one of NaOH and KOH).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The solution of comprises water. The colloidal dispersion comprises water and at least one water-soluble substance capable of stabilizing the colloidal dispersion. The water-soluble substance is present in the solution and is added to the solution at least one of after and together with the hydride compounds. The water-soluble substance is at least one of (cyclo)aliphatic alcohols (having up to 6 carbon atoms and up to 6 hydroxy groups), 2-4C alkylene glycols, di(2-4C alkylene glycols), poly(2-4C alkylene glycols), mono-1-4C-alkyl ethers of 2-4C alkylene glycols, di(2-4C alkylene glycols) and poly(2-4C alkylene glycols), di-1-4C-alkyl ethers of 2-4C alkylene glycols, di(2-4C alkylene glycols) and poly(2-4C alkylene glycols), ethylene oxide/propylene oxide block copolymers, ethoxylated aliphatic polyols, propoxylated aliphatic polyols, ethoxylated and propoxylated aliphatic polyols, 1-6C aliphatic ethers, 1-6C aliphatic ketones, 1-6C aliphatic aldehydes, 1-4C-alkyl esters of 1-4C alkanoic (aliphatic) acids and primary, secondary and tertiary aliphatic amines having a total of up to 10 carbon atoms (preferably methanol, ethanol, propanol, isopropanol, ethylene glycol, diethylene glycol, 1,2,4-butanetriol, trimethylolpropane, pentaerythritol, sorbitol, glycerol, acetone, methyl ethyl ketone, diethyl ketone, methyl acetate, ethyl acetate, dioxan, tetrahydrofuran, diglyme, triglyme, monoethanolamine, diethanolamine, triethanolamine, monopropanolamine, dipropanolamine and tripropanolamine). The weight ratio of water and water-soluble substance is 200:1 - 2:1 (preferably 200:1 - 3:1). In the process (b), the hydroxide ion providing compounds are employed in a total concentration of at least 0.5 mole per liter of fuel or fuel concentrate and the hydride compounds are employed in a total concentration of at least 2 moles per liter of fuel or fuel concentrate. In the method (p2), the fuel concentrate and the polar solvent comprise water, where the polar solvent comprises water in an amount of at least 75 wt.%. In the method (p2), the fuel concentrate has a hydroxide ion concentration of at least 0.5 mole per liter and the polar solvent is added in an amount which results in a hydroxide ion concentration of the fuel of not greater than 90% of the hydroxide ion concentration of the fuel concentrate. The weight ratio of the fuel concentrate and the polar solvent is 5:1 - 1:5.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The at least one water-soluble substance comprises at least one of a water-soluble polymer and water-swellable polymer. The polymer has an initial particle size of 0.02 - 50 micron. EXAMPLE - A deionized water (1747 g) was added to KOH (water content about 15 wt.%) (1250 g). The resultant mixture was first stirred manually and then with a magnetic stirrer until a transparent solution was obtained. After the solution was cooled to room temperature (20 - 30degreesC) it was transferred to the mixing of a combined high speed disperser and planetary mixer. Following the addition of ethylene glycol (210 g) to the mixing can, the mixer was operated at 60 revolutions per minute (rpm) (planetary mixer) and 600 rpm (high speed mixer), respectively. After 5 minutes of mixing, KBH4 (1495 g) was added to the mixture and mixing was continued for 40 minutes at 70 rpm (planetary mixer) and 600 rpm (high speed disperser), respectively, to afford a concentrate of paste-like consistency. A fuel for a fuel cell was prepared from the obtained concentrate by adding deionized water to the paste in a weight ratio paste:water of 1:1.25. The resultant mixture was stirred at room temperature until a milky dispersion without lumps was obtained (with manual stirring usually after 5 - 10 minutes).