TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Components: The active material particles have an average size of less than 10 microns, preferably below 200 nm. The active material particles are formed by a single element M, an alloy of M-lithium, or a composite material containing the element M or M-lithium alloy and conductor material. The conductor material comprises carbon or a metal which does not react with lithium. The electronic conductor is carbon black, SP carbon, acetylene black, carbon nanofibers or carbon nanotubes. The active electrode materials are silicon particles or nanoparticles. The total quantity of active electrode material, binder, and electronic conductor introduced into the aqueous acid is 10-80 wt.%.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The aqueous medium has a buffered pH of less than or equal to 4, obtained by adding a strong base and an organic acid. The strong base is an alkali metal hydroxide and organic acid is glycine, aspartic acid, bromoethanoic acid, bromobenzoic acid, chloroethanoic acid, dichloroethanoic acid, trichloroethanoic acid, lactic acid, maleic acid, malonic acid, phthalic acid, isophthalic acid, terephthalic acid, picric acid, salicylic acid, formic acid, acetic acid, oxalic acid, malic acid, fumaric acid or citric acid. The amount of organic acid is such that it corresponds to a concentration of greater than 1.104 mole per gram of element M and the mass ratio of less than 10%.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polymer binder is an electrochemically stable polymer, in the potential window of 0-5 V versus lithium(0)/lithium(+), insoluble in liquid solvent used as liquid electrolyte, and door functions capable of reacting with hydroxy groups in acid medium. The polymer is copolymers of acrylic acid, acrylamide, styrene sulfonic acid, maleic acid, itaconic acid, lignosulfonic acid, allylamine and ethylacrylic acid, polysiloxanes, epoxy-amine polymers, polyurethanes or carboxymethyl. EXAMPLE - Citric acid (3.842 g) and potassium hydroxide (0.402 g) were dissolved in water (100 ml) to give acid solution. In the obtained solution (0.5 ml), nanoscale silicon (160 mg), carboxymethyl cellulose acetylene black (16 and 24 mg) was dispersed. The dispersion was treated and milled for 1 hour at 500 rpm to give composition. The composition was applied on a copper current collector having a thickness of 25 mu m and an area of 10 cm2, and then dried at room temperature for 12 hours, and at 100 degrees C under vacuum for 2 hours to give electrode.