Organic/inorganic sulfur may be key for safe rechargeable lithium batteries
We have come a long way from leaky sulfur-acid automobile batteries, but modern lithium batteries still have some down sides. Now a team of Penn State engineers have a different type of lithium sulfur battery that could be more efficient, less expensive and safer.
This is one of the lithium sulfur coin batteries being developed in Penn State's Energy Nanostructure Laboratory (E-Nano).
Patrick Mansell, Penn State
Donghai Wang, left, looks on as post doctoral candidate Guoxing Li assembles a lithium sulfur battery. Dr. Wang oversees the Energy Nanostructure Laboratory at Penn State's Materials Research Lab. His work focuses on nanomaterial development for clean energy technologies, such as batteries, solar cells, fuel cells, and environmental remediation.
Patrick Mansell, Penn State
"We demonstrated this method in a coin battery," said Donghai Wang, associate professor of mechanical engineering. "But, I think it could eventually become big enough for cell phones, drones and even bigger for electric vehicles."
Lithium sulfur batteries should be a promising candidate for the next generation of rechargeable batteries, but they are not without problems. For lithium, the efficiency in which charge transfers is low, and, lithium batteries tend to grow dendrites -- thin branching crystals -- when charging that do not disappear when discharged.
The researchers examined a self-formed, flexible hybrid solid-electrolyte interphase layer that is deposited by both organosulfides and organopolysulfides with inorganic lithium salts. The researchers report that the organic sulfur compounds act as plasticizers in the interphase layer and improve the mechanical flexibility and toughness of the layer. The interphase layer allows the lithium to deposit without growing dendrites. The Coulombic efficiency is about 99 percent over 400 recharging discharging cycles.
"We need some kind of barrier on the lithium in a lithium metal battery, or it reacts with everything," said Wang.
Sulfur is a good choice because it is inexpensive and provides the battery with high-charge capacity, higher-energy density so a lithium sulfur battery has more energy. However, a lithium sulfur battery forms an inorganic coating in the battery that is brittle and cannot tolerate changes in volume. The inorganic sulfur interface cannot sustain high energy. In a lithium sulfur battery, the electrolyte dries up and the bulk lithium corrodes. The lithium dendrites that form can create short circuits and other safety hazards.
"Potentially we can double the energy density of conventional DC batteries using lithium sulfur batteries with this hybrid organosulfide/organopolysulfide interface," said Wang.
They can also create a safer, more reliable battery.
To create their battery the researchers used an ether-based electrolyte with sulfur-containing polymer additives. The battery uses a sulfur infused carbon cathode and a lithium anode. The organic sulfur in the electrolyte self-forms the interphase layers.
The researchers report that they "demonstrate a lithium-sulfur battery exhibiting a long cycling life -- 1000 cycles -- and good capacity retention.
Original publication
Other news from the department science
These products might interest you
Battery Testing Services by Battery Dynamics
Learn more about the performance and service life of your battery cells in less time
Benefit from modern measurement technology and an experienced team
Batt-TDS by ystral
YSTRAL Batt-TDS mixing and dispersing machine
Boost your battery slurry process
Get the chemical industry in your inbox
From now on, don't miss a thing: Our newsletter for the chemical industry, analytics, lab technology and process engineering brings you up to date every Tuesday and Thursday. The latest industry news, product highlights and innovations - compact and easy to understand in your inbox. Researched by us so you don't have to.
Most read news
See the theme worlds for related content
Topic World Battery Technology
The topic world Battery Technology combines relevant knowledge in a unique way. Here you will find everything about suppliers and their products, webinars, white papers, catalogs and brochures.
Topic World Battery Technology
The topic world Battery Technology combines relevant knowledge in a unique way. Here you will find everything about suppliers and their products, webinars, white papers, catalogs and brochures.
