Scientists develop new low-cost electrolyte for lithium-ion batteries

Credit: Angewandte Chemie International Edition (2024).

Researchers have developed a new type of battery electrolyte that could make lithium-ion batteries more affordable and environmentally friendly.

Published in the journal Angewandte Chemie International Edition, this breakthrough involves a low-concentration electrolyte that maintains high performance while potentially reducing production and recycling costs.

Lithium-ion batteries are a crucial part of modern life, powering everything from smartphones to electric vehicles and energy storage systems.

These batteries typically use a component called an electrolyte to transport ions between the cathode and anode, enabling the battery to generate power.

The composition of this electrolyte significantly impacts the battery’s efficiency and longevity.

Traditionally, lithium-ion batteries use a high concentration of lithium salts in their electrolytes, which can be expensive and environmentally harsh.

Recognizing the need for a more sustainable alternative, a team of scientists from Ningbo University in China and the University of Puerto Rico-Rio Piedras Campus in the U.S. focused on developing an electrolyte with a much lower concentration of lithium salts.

The new electrolyte uses a lithium salt known as LiDFOB (lithium difluoro(oxalato)borate), which is not only cheaper than the commonly used lithium hexafluorophosphate (LiPF6) but also more stable and less toxic.

This stability allows the batteries to be manufactured in less controlled environments, which could further reduce costs.

In their study, the researchers demonstrated that this new electrolyte, when used with standard battery materials like lithium cobalt oxide cathodes and graphite anodes, offers excellent performance.

Despite its low salt content—just 0.16 mol/L or 2% by weight—it provides sufficient ionic conductivity (4.6 mS/cm) for efficient battery operation.

One of the key advancements of this electrolyte is its ability to form a robust inorganic layer on the electrodes.

This layer is crucial for protecting the electrodes and extending the battery’s life by preventing excessive breakdown of the solvent materials within the battery.

The resulting batteries show outstanding cycling stability, meaning they can be charged and discharged many times without significant loss of capacity.

Moreover, unlike the traditional LiPF6, LiDFOB does not decompose into toxic and corrosive substances when exposed to moisture. This feature makes the batteries safer to handle and recycle, contributing to an overall increase in sustainability.

With these promising results, the new ultralow-concentration electrolyte offers a glimpse into the future of lithium-ion batteries, where cost, performance, and environmental impact are all optimized.

This development could pave the way for more widespread adoption of electric vehicles and renewable energy technologies, making a significant impact on reducing our carbon footprint.

Source: Wiley.