Introduction

As the world shifts toward cleaner energy sources, the importance of energy storage technology becomes increasingly apparent. Batteries have proven to be a reliable source of energy storage. However, not all batteries are created equal. In this blog, we will compare two up-and-coming battery technologies - Lithium-Sulfur (Li-S) and Zinc-Air batteries - for energy storage.

Lithium-Sulfur Batteries

Lithium-Sulfur batteries are one of the most promising battery technologies currently under development. They pack a higher energy density than their popular lithium-ion counterparts. Energy densities of up to 500 Wh/kg have been reported in research laboratories, whereas commercial lithium-ion batteries have energy densities of up to 250 Wh/kg [1]. That means Li-S batteries can store twice as much energy as other batteries while using less space.

One of the key advantages of Li-S batteries is their low cost. Sulfur is a relatively abundant element and much less expensive than the cobalt and nickel used in traditional lithium-ion batteries. However, Lithium-Sulfur batteries have a shorter lifespan than lithium-ion batteries, and therefore they need to be replaced more frequently.

Zinc-Air Batteries

Zinc-Air batteries, on the other hand, have been commercially available for several years. These batteries have a higher energy density than lithium-ion batteries, with energy densities of up to 400 Wh/kg [2]. Furthermore, they have a longer lifespan than Lithium-Sulfur batteries, with an average lifespan of 7-10 years [3].

Another significant benefit of Zinc-Air batteries is their environmental friendliness. Zinc is not only abundant but also recyclable, making it the preferred choice for many eco-friendly companies.

How Do They Compare?

Now that we've compared the two types of batteries' advantages, let's compare them from a practical viewpoint. An average lithium-ion battery can last for about 500 cycles, accounting for about 3-5 years of usage. In contrast, a lithium-sulfur battery has a shorter lifespan, which can compromise durability [4]. On the other hand, Zinc-Air batteries can last for an average of 5,000 cycles or around seven to ten years (depending on usage intensity), thanks to their stable structure and fewer side reactions [5].

In terms of cost, Lithium-Sulfur batteries are cheaper than traditional lithium-ion batteries. At the same time, Zinc-Air batteries require more significant initial investment than other battery types but are expected to pay off in the longer run [6].

Conclusion

Both Lithium-Sulfur and Zinc-Air batteries offer significant advantages over traditional lithium-ion batteries. However, they are not interchangeable and will have different use cases. For energy storage applications requiring long cycle lives and higher energy densities, Zinc-Air batteries would be the preferred choice. At the same time, Lithium-Sulfur batteries are ideal for applications where cost is a primary consideration.

References

1. Zhao Y, Gao P, Hu YS, Li H, Chen L (2013). A new type of Li-S battery with Li2S cathode solvent. Adv Mater. 25: 5794–5799.
2. https://www.sciencedirect.com/science/article/pii/S0013468618339864
3. https://ieeexplore.ieee.org/abstract/document/1598495
4. https://www.sciencedirect.com/science/article/pii/S2352152X16300832
5. https://www.sciencedirect.com/science/article/pii/S2352152X16300832
6. https://www.azocleantech.com/article.aspx?ArticleID=745