Will all-solid-state batteries become a’game changer’ that shakes the market? [Science]

Lithium-ion batteries are currently the most used type of battery. Both prismatic, pouch, and cylindrical batteries are packaged differently with lithium-ion batteries. The’all-solid-state battery’ is attracting the most attention as a next-generation’game changer’ battery technology that will push out lithium-ion batteries.

Recently, Japanese automobile company Toyota unveiled a prototype of an electric vehicle equipped with an all-solid battery and announced a plan to establish a mass production system by 2025. It is known that Toyota currently holds more than 1,000 patents for all-solid-state batteries. This is about 40% of all solid battery patents around the world.

To understand the all-solid-state battery principle, you must first understand the lithium-ion battery principle. Lithium ion is a state in which lithium metal loses electrons and bears a positive (+) charge. When lithium ions in the positive (+) pole move to the negative (-) pole, electricity flows. At this time, an electrolyte is a medium that transfers ions between the positive and negative electrodes of the battery. Lithium-ion batteries use a liquid electrolyte.

On the other hand, all-solid-state batteries use solid-state electrolytes. Because of the use of solid materials, the risk of explosion inherent in lithium-based batteries can be greatly reduced.

All-solid-state batteries also have a short charging time. In theory, charging is completed in 5 to 10 minutes.

It is also known that it can run about 800km with a single charge. Tesla’s’Model Y’, which was recently released in Korea, can travel about 500km with a single charge.

The ease of reducing size and weight is another strength of all-solid-state batteries. Because the battery volume is small, automakers can reserve more space when designing vehicles.

In addition to the all-solid, another candidate for game changer is the lithium metal battery. The lithium metal battery is a next-generation battery made of lithium metal from an anode material, one of the core materials for secondary batteries.

Currently, lithium-ion batteries mainly use graphite as an anode material. The strength of lithium metal batteries is their durability. It has more than twice the durability compared to the same size lithium-ion battery.

The high energy density and long driving distance of a single charge is also a competitive advantage of lithium metal batteries.

Lithium-sulfur batteries are also recognized for their potential. Lithium-sulfur batteries are batteries using sulfur (S) as a positive electrode material. It is different from a lithium-ion battery that has nothing on the positive electrode. Lithium metal enters the negative electrode in the same way as a lithium ion battery. When lithium and sulfur meet, it becomes lithium sulfide (lithium polysulfide), and the principle of lithium-sulfur batteries is to store energy generated in this process. Lithium-sulfur batteries theoretically have five times higher energy density than conventional lithium-ion batteries.

However, lithium-sulfur batteries were not easy to commercialize due to the low electrical conductivity of sulfur and a short lifespan due to volume changes occurring during charging and discharging.

If commercialization is successful, lithium-sulfur batteries are evaluated to be able to replace lithium-ion batteries as economical batteries. Also, since sulfur is a material that exists abundantly on the earth, it can significantly reduce the cost of batteries.

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