Lithium-Sulfur Batteries: The Future Of Electric Mobility

After many years of research on industrial solar energy storage by several companies and science and technology institutes, lithium-sulfur (Li-S) batteries seem to be a reality soon. With a large capacity, economic, high performance, and sustainable solutions, lithium-sulfur (Li-S) batteries could change the world as we know it. Today, we will show what lithium-sulfur batteries are ideal industrial solar energy storage solutions and how they work, what advantages they bring, and when it is calculated that they could be a reality.

What are lithium-sulfur batteries?

Lithium-sulfur batteries are innovative chemical batteries that, together with solid-state batteries, promise to revolutionize the rechargeable battery market. These types of batteries have been in development since 2004 by the British company, OXIS Energy. Still, it was not until very recently that they began to be a reality thanks to various scientific studies carried out by multiple universities worldwide.

This technology would also end all the problems of electric car batteries. Their high energy density, between five and eight times higher than current ones, allows a much higher amount of energy to be stored for the same battery weight. And, therefore, it would offer greater autonomy at a lower cost. Thanks to this, electric airplanes can also become a reality, which requires great freedom and where weight and cost are important variables to consider.

Other characteristics of lithium-sulfur batteries in regards to industrial solar energy storage are their super-fast charging, their compatibility with current systems, high performance, light, safe, maintenance-free, and a lower environmental impact than Li-ion batteries. Because instead of cobalt (a scarce and polluting material), it uses sulfur as a catalyst, a cheap, abundant, and recyclable material.

How do lithium-sulfur batteries work?

The theoretical operation of lithium-sulfur batteries is very similar to that of any other battery. The big difference is found in the materials used and the chemical reaction they cause. The positive pole or anode is metallic lithium, while the negative or cathode is made of sulfur. However, as this material is not very conductive, a carbon matrix forms the positive electrode.

As catalyst electrolytes such as non-aqueous organic liquid electrolytes, ionic liquid-based electrolytes, and non-liquid electrolytes are used. The electrolyte between the two battery electrodes is responsible for transporting the electrical charges between them.

The big problem with these batteries so far has been that due to the nature of the chemical reactions, there is a rapid degradation of the sulfur cathode and corrosion of the lithium anode, which leads to greater battery degradation and a useful life very limited. However, thanks to the latest research, this has improved significantly. Thanks to a safe electrolyte that protects the lithium metal or the use of cobalt oxalate as a catalyst.

New sulfur batteries with boron substrate.

A team of researchers from the Hong Kong University of Science and Technology has developed a new, high-capacity, long-life lithium-sulfur battery thanks to boron nano particles in the cathode. The creation of this substrate avoids the large volume changes that occur in the charging and discharging processes, increasing the useful life and allowing an initial energy capacity up to 1.415 mAh/gram to be reached.

Li-S battery technology is one of the most promising today due to its technical, economic, and environmental advantages. The use of solid lithium combined with a liquid organic electrolyte involves several inherent problems.

The large volume change experienced by solid sulfur is the cause of the instability of the charge and discharge cycles, which pulverizes the entire cathode architecture. This also brings safety problems associated with the high flammability of the liquid organic electrolyte due to the growth of dendrites on the lithium anode. These small rigid structures that grow inside lithium battery-like needles can pierce the separator that prevents the electrodes (cathode and anode) from touching, accelerating the failure of the battery and even causing its fire.

Advantages of Li-S batteries as industrial solar energy storage

Lithium-sulfur Li-S batteries promise to revolutionize the rechargeable battery industry: industrial solar energy storage, electric cars, smartphones, heavy industrial vehicles, defense, space aeronautics, marine, and electric aviation are some of the fields that could make use of them. Take advantage of its many advantages:

• Excellent self-sufficiency
• Light
• Safe
• High resistance
• High durability
• Low cost
• Pressure tolerance
• Discharge depth
• Sustainable

 The only and great disadvantage that this type of battery seemed to have is its internal wear due to the chemical reaction. Still, once this obstacle is overcome, as it seems to have happened, it is a matter of time before these types of batteries come into our lives.