Electrolytic water and the oxyhydrogen fuel cell

Electrolytic water is a very important experiment in the chemistry of junior middle school.And Oxyhydrogen fuel cell,introduced in the textbook of the senior middle school,is a new and functional cell,which is very prospective in the future..There is a close relation between the two.When the experiment of electrolytic water has been carried on for a certain time,some hydrogen(H2) and oxygen(O2) will exist in the device.And if you cut off the external power supply at this time,the device will be an oxyhydrogen fuel cell