Hydrogen has been studied for more than 200 years since Lavoisier gave it its name in the 18th century. As a gaseous substance, people have been trying to improve the efficiency of hydrogen energy utilization by increasing its density and storing it. However, hydrogen storage is difficult for the following three reasons.

First, hydrogen is the lightest of all the elements. In its standard state, it has a density of 0.0899g/L, 1/10,000th that of water. At -252.7℃, it can be changed into a liquid, with a density of 70g/L, only 1/15 of water.

Second, as the number one element on the periodic table, hydrogen has such a small atomic radius that it can pass through most of the tiny holes that are invisible to the naked eye. Not only that, but hydrogen can even pass through thick steel plates at high temperatures and pressures.

Third, hydrogen is very active, very poor stability, leakage is prone to combustion and explosion. Hydrogen explosion limit: 4.0~74.2% (hydrogen by volume to the total volume of the mixture).