The development of solid hydrogen storage materials makes the use of hydrogen energy applauded and popular

Original source: Science and Technology Daily

Reporter: Zhang Ye

Compared with high-pressure gas and liquid hydrogen storage, solid hydrogen storage has the advantages of high volumetric hydrogen storage density, low working pressure, and good safety performance.

——Zhou Shaoxiong, Director of the Institute of Advanced Energy Materials and Applied Technology, Jiangsu Industrial Technology Research Institute

With 2 small hydrogen tanks, an electric bicycle can travel 120 kilometers; you don’t have to worry about running out of hydrogen, you can buy and replace them at convenience stores on the streets and alleys; even if the hydrogen tanks are damaged, there is no danger, and all that is poured out of the tanks is alloy powder .

This is not a scene in a science fiction film, but a Jiangsu company at the 20th China Northern International Bicycle and Electric Bicycle Exhibition in 2021, showing two prototype vehicles that use hydrogen energy as a power generation system.

In recent years, buses, trucks, refrigerated vehicles, and backup power supplies that use solid-state hydrogen storage as energy sources have come out in my country.

How did solid-state hydrogen storage change the two problems of high-density storage and safe application of hydrogen? Once the hydrogen storage and transportation problem is solved, in which areas will hydrogen energy play a role? With these questions in mind, a reporter from Science and Technology Daily interviewed Dr.

Storage and transportation issues affect the use of hydrogen energy

The chemical element hydrogen (H), ranked first in the periodic table, is the smallest of all atoms.

But this colorless and tasteless "little guy" is the most common element in the universe.

"We are still living in the carbon era, but in the future, hydrogen energy will be a pivotal energy source.

At present, my country is facing two major challenges of energy security and carbon emissions.

However, since human beings realized that hydrogen can be burned, more than 200 years have passed, and the efficient use of hydrogen energy is still progressing slowly.

"The utilization of hydrogen energy involves three links: hydrogen production, storage and transportation, and application.

At present, the storage and transportation of hydrogen are mainly divided into three methods: gas, liquid and solid.

Gaseous hydrogen storage is more common and can be divided into low pressure and high pressure.

At a certain low temperature, hydrogen will exist in liquid form.

　　Compared with other non-fossil energy sources such as fossil energy or electricity, hydrogen energy has been in an embarrassing situation because it has not yet solved the problem of storage and transportation.

　　The cost of magnesium-containing solid-state hydrogen storage system is close to that of lithium batteries

　　"Compared to high-pressure gas and liquid hydrogen storage, solid hydrogen storage has the advantages of high volumetric hydrogen storage density, low working pressure, and good safety performance.

　　Solid-state storage requires hydrogen storage materials, and the most mature hydrogen storage materials at present are mainly metal alloys.

　　Hydrogen storage alloys are generally composed of two parts, one of which is a hydrogen absorbing element or an element with a strong affinity for hydrogen.
It controls the amount of hydrogen storage and is the key element of the hydrogen storage alloy, mainly including titanium, magnesium, etc.
; Some of them are elements that have little or no hydrogen absorption.
Common ones are iron and nickel.

　　These alloy materials react chemically with hydrogen under low temperature conditions, and the hydrogen is decomposed into hydrogen atoms on the surface.
There are a large number of fine crystal lattices inside the alloy material, and hydrogen atoms diffuse into the voids inside the crystal lattice to form metal hydrides.

　　It is also very simple to "release" the hydrogen atoms.
Only by applying a certain amount of heat, the hydrogen storage material can precipitate hydrogen gas.

　　Zhou Shaoxiong told reporters that the low-temperature solid-state hydrogen storage materials they have developed can store hundreds of times the volume of hydrogen, so its hydrogen storage density is higher than that of liquid hydrogen.
These alloy materials have very stable properties, will not burn or explode, have good reversibility, and are not less than 5000 times repeated.

　　"Take a new type of hydrogen storage material that we developed as an example.
The main components are magnesium and rare earth elements lanthanum, cerium, etc.
, which are melted and smelted in a furnace, cooled to shape, and then crushed into powder.
" Zhou Shaoxiong said that magnesium is the natural world.
A ubiquitous element, lanthanum and cerium are rich in rare earth elements, so the overall cost has approached lithium batteries.

　　In recent years, countries around the world have made a lot of progress in the application of solid hydrogen storage and the research and development of new hydrogen storage materials.
Mature hydrogen storage materials have been applied in many fields such as combined heat and power, energy storage, and on-board fuel cell hydrogen source systems.
A German company even uses solid-state hydrogen storage systems in fuel cell submarines.

　　According to Zhou Shaoxiong, their latest development of magnesium-containing hydrogen storage materials has a storage capacity of 110 kilograms per cubic meter, which far exceeds the "ultimate goal" of hydrogen storage proposed by the U.
S.
Energy Administration.
However, its application is restricted by the excessively high hydrogen discharge temperature.
It needs to reach 250°C or higher.
At present, scientists are using various methods to regulate its thermodynamics, kinetics and cycle life performance, hoping to achieve commercial use as soon as possible.

　　Hydrogen turns into a "solid fuel tank" or changes the future energy pattern

　　Companies such as Japan’s Toyota and South Korea’s Hyundai have invested heavily in research and development of hydrogen energy vehicles over decades, but due to the bottleneck in the construction of hydrogen refueling stations, market promotion has not been smooth.

　　"Because the problem of hydrogen energy storage and transportation has not been solved, and the cost of fuel cells is high, hydrogen energy vehicles are still in the stage of government subsidies and demonstration operations.
" Zhou Shaoxiong said that when solid hydrogen storage materials are developed, hydrogen energy utilization will be more effective.
Greatly changed.

　　For example, the integration of a solid-state hydrogen storage device with a fuel cell can make full use of the waste heat of the fuel cell, absorb heat and release hydrogen, reduce the thermal energy consumption of the system, and improve the energy efficiency of the entire fuel cell power system.

　　"At present, we have built the only domestic production line with an annual output of 800 tons of hydrogen storage materials, and cooperated with companies such as No.
9 Company and Yonganxing to launch motorcycles and electric bicycles with solid-state hydrogen storage power systems.
" Zhou Shaoxiong told reporters.
, The low-temperature solid-state hydrogen storage material technology is mature, the cost is controllable, and the whole set of devices is domestically produced, and commercial applications can be realized without government subsidies.

　　Zhou Shaoxiong introduced that the 100-watt hydrogen fuel cell power generation system they developed using solid hydrogen storage as the hydrogen source can drive a bicycle for 80 kilometers with only 55 grams of hydrogen.
The 55 grams of hydrogen are stored in an ordinary mineral water bottle.
In the tank, the hydrogen storage pressure is only equivalent to that of an ordinary balloon.

　　Zhou Shaoxiong boldly predicted: "Solid-state hydrogen storage tanks can be made into products like dry batteries.
In the future, they can be purchased anywhere in convenience stores or supermarkets.
You can also put used hydrogen energy bottles in storage boxes and be replaced by couriers daily.
"

　　In the future, the storage and transportation problem will be solved.
The application of hydrogen energy is not only the fuel cell vehicle that has attracted much attention, but also includes hydrogen power generation, industrial applications and building applications.
It can not only be used as a building cogeneration power supply, a reliable power supply for microgrids and The backup power supply of mobile base stations can also be combined with digital technology, allowing the hydrogen fuel cell power system that uses solid-state hydrogen storage as the hydrogen source to play an important role in many fields such as unmanned driving, military individual soldiers, and deep-sea equipment.