NOVELTY - Improved-electrolyzer apparatus (10) includes two electrodes press-formed from very thin sheet metal multi-folded and clamped by top metallic caps of the same material, and a top cover center wall provided with lateral wedge shaped guide rims and fitted with side ridges (18) to provide electrolyte circulation surrounding the electrodes and electrical current flow between the two compartments through a bottom slot.    USE - The invention is used for electrolysis of water. It can be used in electric power and hydrogen fuel and oxygen production, and in scuba diving aqualung. It can also be used to provide hydrogen fuel to vehicles and to convert braking power generated electricity back to hydrogen fuel for storage (all claimed).    ADVANTAGE - The invention is very efficient and reliable by having the electrodes expose a very large surface area to reduce contact resistance, while having insulating dividing wall form two single compartments to achieve high voltage insulation between the electrodes immunity to arcing and short circuits between the electrodes. It can be applied from miniature to immensely powerful embodiments.    DETAILED DESCRIPTION - Improved-electrolyzer apparatus includes insulating watertight enclosure (11) having two electrodes of equal surface area press-formed from very thin sheet metal multi-folded and clamped by top metallic caps of the same material adapted with indexed quick coupling electrical terminals (14, 17) and respective gas quick coupling outlets of insulating material fitted with spring loaded check valves. A water electrolyte quick coupling (13, 15, 16) of insulating material is adapted to the positive electrode top metallic cap having a spring loaded check valve and a float operated check valve for automatic electrolyte level control. A watertight cover (12) is adapted with coupling-sealing O-rings and locked in position by a retainer sealed over by a watertight sealing compound. A top cover center wall is provided with lateral wedge shaped guide rims and fitted with side ridges to provide electrolyte circulation surrounding the electrodes and electrical current flow between the two compartments through a bottom slot to provide high voltage insulation, prevent arcing and short circuits between the electrodes and to ensure separation of the hydrogen and oxygen formed gas within.    DESCRIPTION OF DRAWING(S) - The figure is a perspective view of an overall assembly of improved-electrolyzer.    Improved-electrolyzer apparatus (10)    Enclosure (11)    Cover (12)    Electrolyte quick coupling (13, 15, 16)    Coupling electrical terminals (14, 17)    Ridges (18)