Electrolysis of water is a MUCH safer method to produce hydrogen.. and oxygen for that matter. Capture off the electrodes, and you can harvest nearly pure gases. Best of all, you know you have a proper mix of hydrogen and oxygen, as your source and endpoints- water- are the same. Energy stored in the chemical bonds is everything else.. In addition, it's pretty impressive once you think about it. It will take quite a while to generate a good volume of gases.. depending on setup, hours or even days. All the energy being dumped in to break the water chemical bonds over all that time... and when ignited, all that energy is released in a fraction of a second. Electrolysis and combustion is a great hands-on example for demonstrating chemical storage of energy!
That all being said, I think you need to read a few things:
"The flammability limits based on the volume percent of hydrogen in air at 14.7 psia (1 atm, 101 kPa) are 4.0 and 75.0. The flammability limits based on the volume percent of hydrogen in oxygen at 14.7 psia (1 atm, 101 kPa) are 4.0 and 94.0."
"The limits of detonability of hydrogen in air are 18.3 to 59 percent by volume"[4]
Don't underestimate the power of the explosive you are dealing with. This is NOT a safe project-- take EXTREME care... and if you have any doubts at ALL, do not do it. You are essentially building a bomb if you try to contain detonating fuel/air vapor. Even if explosion is avoided, the flame jet (which is invisible) will ignite ANYTHING it's close to- it will be a high-powered, invisible blowtorch (gas-fueled rocket?). In either case, very dangerous.