News

Oct 27, 2024

Li-S EV batteries last longer with higher energy using SMU method

Southern Methodist University (SMU) engineers have made significant strides in battery technology, potentially transforming the EV landscape. Bojan Stojkovski Li-S batteries are considered a promising

Southern Methodist University (SMU) engineers have made significant strides in battery technology, potentially transforming the EV landscape.

Bojan Stojkovski

Li-S batteries are considered a promising renewable energy source as these can store more energy. (Representational image)

Freepik

SMU mechanical engineer Donghai Wang and his research team are working to improve efficiency of lithium-sulfur batteries, which have not yet reached their potential as renewable batteries for electric vehicles and other devices.

They have found a way to extend the lifespan of these Li-S batteries and increase their energy levels compared to current renewable batteries.

The team addressed a common issue with Li-S batteries known as polysulfide dissolution, which occurs over time and reduces battery life. Their approach helps to minimize this problem, potentially leading to more durable battery solutions.

Wang also emphasized the potential of this research to result in more durable, long-lasting batteries. His work focuses on the design and synthesis of nanostructured functional materials, as well as energy storage technologies, including Li-ion batteries and advancements beyond Li-ion technology.

A study published in the journal Nature Sustainability highlights that the team’s newly developed hybrid polymer network cathode enables lithium-sulfur batteries to achieve capacities exceeding 900 mAh/g (milliampere-hours per gram), compared to the typical 150-250 mAh/g found in lithium-ion batteries. This advancement means the Li-S batteries can store significantly more electrical energy.

Additionally, the new cathode demonstrates excellent cycling stability, surpassing the performance of conventional lithium-sulfur batteries. Cycling capacity refers to how many times a battery can be charged and discharged before experiencing a significant decline in capacity. A higher cycling capacity translates to a longer-lasting battery.

Lithium-sulfur (Li-S) batteries are considered a promising renewable energy source because they are more cost-effective and can store more energy than traditional ion-based rechargeable batteries.

However, there is a significant challenge with these batteries, as the battery community has faced difficulties in addressing the negative effects of polysulfide dissolution. All batteries consist of a positive terminal and a negative terminal. A chemical reaction occurs between these two terminals, generating power or electricity.

In lithium-sulfur (Li-S) batteries, a sulfur-based positive electrode, known as the cathode, is paired with a lithium metal negative electrode, called the anode. The electrolyte, a substance that allows ions to move between these two electrodes, sits in between. However, sulfur is not the perfect material for an electrode, as it can lead to issues such as polysulfide dissolution that impact battery performance.

Wang and his team have developed a hybrid polymer network cathode to address the issue of polysulfide dissolution in lithium-sulfur batteries. When lithium ions bond with sulfur at the cathode, they form soluble polysulfide molecules that move into the electrolyte, leading to cathode degradation and reducing the battery’s ability to endure multiple charging cycles.

“This combination allows for real-time re-bonding and adsorption of any unbound sulfur species, thus effectively eliminating soluble polysulfides and extending the battery’s cycle life.” Wang concluded.

Stay up-to-date on engineering, tech, space, and science news with The Blueprint.

By clicking sign up, you confirm that you accept this site's Terms of Use and Privacy Policy

Bojan Stojkovski Bojan Stojkovski is a freelance journalist based in Skopje, North Macedonia, covering foreign policy and technology for more than a decade. His work has appeared in Foreign Policy, ZDNet, and Nature.

a day ago

a day ago

a day ago

a day ago