Solution enables a battery with both high efficiency & current density
Dendrites — the microscopic, pin-like fibers that cause rechargeable batteries to short circuit — create fire hazards and can limit the ability of batteries to power our smart phones and store renewable energy for a rainy day.
Now a new electrolyte for lithium batteries that’s described in Nature Communications eliminates dendrites while also enabling batteries to be highly efficient and carry a large amount of electric current. Batteries using other dendrite-limiting solutions haven’t been able to maintain both high efficiencies and current densities.
“Our new electrolyte helps lithium batteries be more than 99 percent efficient and enables them to carry more than ten times more electric current per area than previous technologies,” said physicist Ji-Guang “Jason” Zhang of the Department of Energy’s Pacific Northwest National Laboratory. “This new discovery could kick-start the development of powerful and practical next-generation rechargeable batteries such as lithium-sulfur, lithium-air and lithium-metal batteries.”
Most of the rechargeable batteries used today are lithium-ion batteries, which have two electrodes: one that’s positively charged and contains lithium and another, negative one that’s typically made of graphite. Electricity is generated when electrons flow through a wire that connects the two. To control the electrons, positively charged lithium atoms shuffle from one electrode to the other through another path: the electrolyte solution in which the electrodes sit. But graphite has a low energy storage capacity, limiting the amount of energy a lithium-ion battery can provide smart phones and electric vehicles.
When lithium-based rechargeable batteries were first developed in the 1970s, researchers used lithium for the negative electrode, which is also known as an anode. Lithium was chosen because it has ten times more energy storage capacity than graphite. Problem was, the lithium-carrying electrolyte reacted with the lithium anode. This caused microscopic lithium dendrites to grow and led the early batteries to fail.
Many have tweaked rechargeable batteries over the years in an attempt to resolve the dendrite problem. In the early 1990s, researchers switched to other materials such as graphite for the anode. More recently, scientists have also coated the anode with a protective layer, while others have created electrolyte additives. Some solutions eliminated dendrites, but also resulted in impractical batteries with little power. Other methods only slowed, but didn’t stop, the fiber’s growth.
Concentrated secret sauce
Thinking today’s rechargeable lithium-ion batteries with graphite anodes could be near their peak energy capacity, PNNL is taking another look at the older designs. Zhang and his team sought to develop an electrolyte that worked well in batteries with a high-capacity lithium anode. They noted others had some success with electrolytes with high salt concentrations and decided to use large amounts of the lithium bis(fluorosulfonyl)imide salt they were considering. To make the electrolyte, they added the salt to a solvent called dimethoxyethane.
The researchers built a circular test cell that was slightly smaller than a quarter. The cell used the new electrolyte and a lithium anode. Instead of growing dendrites, the anode developed a thin, relatively smooth layer of lithium nodules that didn’t short-circuit the battery.
After 1,000 repeated charge and discharge cycles, the test cell retained a remarkable 98.4 percent of its initial energy while carrying 4 milliAmps of electrical current per square centimeter of area. They found greater current densities resulted in slightly lower efficiencies. For example, a current density as high as 10 milliAmps per square centimeter, the test cell maintained an efficiency of more than 97 percent. And a test cell carrying just 0.2 milliAmps per square centimeter achieved a whopping 99.1 percent efficiency. Most batteries with lithium anodes operate at a current density of 1 milliAmps per square centimeter or less and fail after less than 300 cycles.
The new electrolyte’s remarkably high efficiency could also open the door for an anode-free battery . . .
The Latest on: Next-generation rechargeable batteries
via Google News
The Latest on: Next-generation rechargeable batteries
- Best Xbox Series X Holiday Gifts for Black Fridayon November 27, 2020 at 6:48 am
Looking for the best Xbox consoles, accessories, and games to buy this holiday? We've got you covered! With the Xbox Series X and Series S, Microsoft has entered the next generation of console gaming.
- Holiday gaming gift guide: What to know about the PlayStation 5, Xbox Series X, and Nintendo Switchon November 26, 2020 at 5:00 pm
This is the first holiday season for the ninth generation of video game consoles, as the PlayStation 5 and Xbox Series X (XSX) have recently hit the market, and Nintendo's hybrid system the Switch ...
- Electric Vehicle Battery Market 2020: Size, Share, Key Drivers and Top Manufacturers Forecast Till 2027on November 24, 2020 at 3:25 am
These vehicles depend on electric batteries to present the essential or the auxiliary power. along these lines any effect ...
- Scientists discover beautiful blue new mineral petroviteon November 19, 2020 at 11:05 am
Petrovite is beautiful to look at, but it could also help inspire advancements in next-generation batteries ... as a component of sodium ion batteries, a type of rechargeable battery that could ...
- Mineral Petrovit Discovered By Russian Scientists, Can Be Used In Rechargeable Batterieson November 18, 2020 at 7:16 am
A team at the University of St. Petersburg, led by Stanislav Filatov, a specialist in crystals (crystallographer) dug out the mineral Petrovite in Kamchatka.
- Battery Revolutions Are Predicted Weekly, But This One Might Be Realon November 17, 2020 at 4:00 pm
Because of an early relationship with battery maker A123 at a time when it was reorganizing under bankruptcy, the fledgling SolidEnergy was able to use the A123’s idled production equipment to work ...
- 3DOM Signs MOU on Battery Energy Storage System for Pathein Industrial City Project in Myanmaron November 17, 2020 at 3:03 am
Relying on 3DOM's cutting-edge Lithium Rechargeable Battery Technology ... and designing next-generation batteries, and by deploying on a global scale businesses that use these technologies.
- Simple method to produce high performing lithium selenium batterieson November 16, 2020 at 10:37 am
Engineers have developed a simple and elegant method of producing high-powered lithium-selenium (Li-Se) batteries. Rechargeable lithium-ion batteries (LIBs) are considered the best hope for next ...
- Team reveals simple method to produce high-performing lithium selenium batterieson November 16, 2020 at 6:45 am
Rechargeable lithium-ion batteries (LIBs) are considered the best hope for next-generation battery technology, thanks to their long-life cycle, high specific power and energy density. However ...
- Surrey University finds simple route to Li-Se batterieson November 16, 2020 at 5:52 am
Rechargeable lithium-ion batteries (LIBs) are considered the best hope for next-generation battery technology, thanks to their long-life cycle, high specific power and energy density. However, they ...
via Bing News