The Water goes into the top of the removable top of the battery. It is stored in the see through chamber of the battery. The water is going to go through a process called electrolysis, where it is divided into hydrogen and oxygen.  Electrolysis is the process of separating water by sending an electric current through it. The hydrogen is the negative charge of the battery and the oxygen is the positive charge of the battery power.  If they put the battery to charge, the electric current that is supposed to charge it will separate the water into hydrogen and oxygen to power the battery.  This will create hydrogen fuel cells so the battery will work.  The only thing is that you must plug it into an electrical current after it is filled with water.  It only needs to be plugged in for a few seconds, enough time for the current to separate the water. Then you can use this battery to power any medium to large Device.