Summary Reader Response Draft 3

The article "How an accidental discovery made this year could change the world" by Lockett (Apr 2022) introduced the discovery of a new type of Lithium-Sulfur battery. Before this discovery, lithium-sulfur batteries typically had 1,000 charge cycles, or about half as many cycles as lithium-ion batteries. Because of this, lithium-ion batteries are still the preferred option even though lithium-sulfur batteries have lower production costs. This will change, though, thanks to the Drexel team's recent discovery.  It was an unexpected discovery as the Drexel team tried to slow down the chemical reactions that create polysulfides as the batteries charge and discharge to extend battery life. While slowing down the chemical reaction, Drexel's team was shocked to discover that one of the sulfur chemical phases could stop the battery from degrading. This chemical phase is called "monoclinic gamma-phase sulfur," according to Drexel's team and the reaction that generates polysulfides stops completely at this stage. This approach worked so well that the battery could undergo 4,000 charge cycles without a drop in capacity, lasting at least twice as long as a lithium-ion battery. This means that lithium-sulfur batteries can now power a variety of activities such as short-haul flights, cargo ships, passenger ferries, and more, increasing the viability of net-zero emissions. In addition, lithium, sulfur, and other components used to make this new battery are readily available on Earth. Hence when this battery is being produced, a stronger supply chain is ensured, and the ecological impact of mining is significantly reduced. With this new chemical phase discovered in sulfur materials, Drexel's team's new lithium-sulfur battery will prove to be better, cheaper, and more environmentally friendly than lithium-ion batteries, and will revolutionize the way the world uses electricity, helping humanity advance towards a greener, carbon neutral society.

One enhancement of this new Lithium-Sulfur battery is its durability. Although compared to lithium-ion designs, lithium-sulfur batteries can achieve 8 times higher energy densities (Zhu,2019). Before this discovery, you could only charge these batteries no more than 100 times due to polysulfide shuttles, a chemical process that reduces battery capacity and charge/discharge efficiency (Lee, 2018). That's not much when you consider that commercial lithium-ion batteries can last 2,000 cycles or more (Staller, 2017). However, the new monoclinic gamma-phase sulfur does not react with carbonate-based electrolytes, which explains why polysulfides are not visible (Modern Science. 2022). And after a year of testing, Dr. Kalra and her colleagues demonstrated the stability of their sulfur cathode after ​​​ 4,000 charge-discharge cycles, about twice that of a lithium-ion battery (Pai et al, 2022). Additionally, their initial battery capacity is roughly three times that of their lithium-ion competitors (Yang et al, 2022). This means that these batteries are one-third the weight of an equivalent lithium-ion battery and last twice as long (Lockett, 2022).

Another feature of Lithium-Sulfur batteries is their material. The cathodes of lithium-ion batteries are mainly made of key minerals such as nickel and cobalt. As EV usage increases, this demand will rise as well. According to a recent study, Europe could face shortages of nickel and cobalt as early as 2030 (Leotaud, 2022). Even worst, there is an insufflation processing infrastructure necessary to transform minerals into battery-friendly components. Slow supply chains, coupled with frenzied demand, have resulted in shortages of battery raw materials, which have driven up prices (Desai 2022). Sulfur, on the other hand, is easier to locate than cobalt and nickel, as it is the tenth most common element on Earth. It is also a by-product of many industrial processes, including petroleum refining. In other words, it is a cheaper and more sustainable raw material (US EPA, nd). Therefore, the entry of sulfur into the market can relieve pressure on the electric vehicle supply chain and reduce the price of the car. By-products can be converted into useful products, which can be one of the main advantages.

However, despite the uplifting discovery, there is still a long way before these new Lithium-Sulfur batteries can be implemented in the real world. Scientists have yet to figure out what actually happened, and they still don't understand why or how this particular sulfur phase is maintained. According to Dr. Kalra, stabilizing gamma sulfur at room temperature and understanding how redox phenomena in lithium-sulfur batteries might be radically altered by this particular crystal structure remain the most prominent questions (Kalra, 2022). "We've been talking to a lot of industry folks to get an understanding of the steps beyond where we are right now. And our understanding for such a technology would be more in the range of five to six years." (Kalra, 2022)

In conclusion, the Drexel team's radical and unexpected achievement could bring much-needed Lithium Sulfur batteries within reach on a commercial scale. This new chemical phase discovered in sulfur materials will fundamentally change the way we think about energy storage, with lower cost, higher power density, and improved durability. Still, the researchers need to demonstrate their improved devices outside the lab, but it’s no longer out of reach.

 

Reference:

Desai, P. (Feb 2022) Costs of nickel and cobalt used in electric vehicle batteries. Reuters

https://www.reuters.com/business/autos-transportation/costs-nickel-cobalt-used-electric-vehicle-batteries-2022-02-03/

 

Kalra, V. (Mar 2022) Introducing a Commercially Stable Lithium-Sulfur Battery. AZO Material

https://www.azom.com/article.aspx?ArticleID=21384

 

Leotaud, V.R. (May 2022) Europe’s Green Deal requires massive amounts of battery metals – study. Mining.Com

https://www.mining.com/europes-green-deal-requires-massive-amounts-of-battery-metals-study/

 

Lee, J.H., Kang, J., Kim, S.W, Halim, W., Frey, M.W., and Joo, Y.L.(Dec 2018) Effective Suppression of the Polysulfide Shuttle Effect in Lithium-Sulfur Batteries by Implementing rGO–PEDOT: PSS-Coated Separators via Air-Controlled Electrospray National Library of Medicine

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6644160/

Lockett, W. (Apr 2022) How an accidental discovery made this year could change the world. The Future

https://bigthink.com/the-future/lithium-sulfur-batteries/?utm_medium=Social&utm_source=Facebook&fs=e&s=cl&fbclid=IwAR1JQ-VrPK4Nt6YauDpwVZrmkeHE1jR0zfHdUdqe1wC5xr4XEabacCNVJLE#Echobox=1658939001-1

 

Modern Science Team. (Mar 2022) “Gamma Sulfur” May Hold the Key to Future Lithium-Sulfur Batteries. Modern Science

https://modernsciences.org/gamma-sulfur-may-hold-the-key-to-future-lithium-sulfur-batteries/

 

Pai, R., Singh, A., Tang, M.H., Kalra, V. (Feb 2022): Stabilization of gamma sulfur at room temperature to enable the use of carbonate electrolyte in Li-S batteries. Communication Chemistry 

https://www.nature.com/articles/s42004-022-00626-2

 

Staller, A. (Feb 2017): Li-sulfur Battery Rivals Cycle Life of Li-ion. The Electrochemical Society

https://www.electrochem.org/ecsnews/li-sulfur-battery-rivals-cycle-life-li-ion/

 

US EPA Archive Document(nd) Sulfur (PDF)

 

Yang, C., Li, P., Yu, J., Zhao, L.D., Kong, L. (Jun 2022): Approaching energy-dense and cost-effective lithium-sulfur batteries: From materials chemistry and price considerations. ScienceDirect

https://www.sciencedirect.com/science/article/pii/S0360544220308252?casa_token=RlBTqBjjUvoAAAAA:cqQd1GvJ3lrats3WuRZTrVGymGjJiXKMFpV8B4OLwU7ewxJOU9dXdS2-zB9sSAuGNpQ0aPkxO1Q

 

Zhu, K., Wang, C., Chi, Z., Ke, F., Yang, Y., Wang, A., Wang, W., Miao, L. (Nov 2019) How Far Away Are Lithium-Sulfur Batteries From Commercialization? Frontiers

https://www.frontiersin.org/articles/10.3389/fenrg.2019.00123/full