This Lithium-Sulfur Battery Keeps on Ticking, Even When Folded — or Sliced in Half

Researchers from the University of Electronic Science and Technology of China and the Tianmu Lake Institute of Advanced Energy Storage have designed a battery, which is rather more robust than the norm, operating as you'd expect even when folded in two — or cut straight across the middle.

"Herein, we design a series of chelating-type binders to stabilize MSₓ [metal sulfides] in carbonate-based electrolytes," the team explains of its work. "Additionally, we have developed a new battery system featuring an MSₓ cathode paired with a prelithiated graphite (LiC₆) anode in a carbonate-based electrolyte, with the aim of achieving higher safety and satisfactory stability."

While the team's paper concentrates primarily on the chemistries involved, it's the prototype battery that is likely to be of most interest to the layman: based on a lithium-sulfur chemistry, the battery promises the potential to scale to equal or greater energy capacities than traditional lithium-ion batteries without the safety concerns — such as the tendency of lithium-ion batteries to overheat or burst into flames when punctured.

To prove the concept, the prototype battery — created by coating its iron-sulfide cathode with polyacrylic acid — was charged and used to drive a small display before being folded in half across its middle. Despite this abuse, the battery not only remained not-on-fire but continued to operate — and did so even when the battery was cut clean in half, albeit with a correspondingly reduced energy capacity.

"Exceptional performance [was] observed in the LiC₆||FeS₂ pouch cell," the researchers conclude of their work, which also included a second coin-cell battery design, "showing no capacity degradation over 100 cycles and excellent safety. This study underscores the potential of conversion-type lithium batteries for achieving long cycle life and high safety."

The team's work has been published in the journal ACS Energy Letters.