Tag: dendrites

Giving solid-state batteries a squeeze keeps them from short-circuiting

Giving solid-state batteries a squeeze keeps them from short-circuiting

SLAC and Stanford researchers found that compressing solid-state battery material reduced the formation of lithium-filled intrusions called dendrites, leading to faster charging and longer battery life.

Key takeways:

  • A SLAC/Stanford University research team found they could prevent short-circuiting of solid-state batteries by deflecting the dendrite propagation direction using mechanical compression.
  • They provided direct evidence that dendrites start in the interior rather than merely at the surface of the electrolyte, settling a long-standing debate within the field.
  • The results could have implications for future battery design, by incorporating built-in mechanical compression or electrolytes with more defect-free interiors that suppress dendrite initiation.

Lithium-ion batteries power transportation and grid storage and enable our digital lives, but these ubiquitous batteries require frequent recharging and can fail over time.    

To make batteries more reliable and longer lasting, researchers are exploring how to replace liquids inside batteries with a solid ceramic substance that could improve their performance. 

But researchers must first overcome a big problem: cracks filled with lithium that form within the solid material during charging, causing the batteries to quickly short-circuit. When that happens, devices powered by these batteries become useless.

Researchers have long debated whether these cracks and the lithium metal inside them, called dendrites, form at the surface or inside the solid material – a key insight needed to figure out how to stop them from forming.

Now, in a study published in the journal Nature, researchers have discovered a way to track these dendrites and suppress them enough to keep the battery from short-circuiting.

Read more on the SLAC website

Gold coating could solve long-standing challenge with zinc batteries

Gold coating could solve long-standing challenge with zinc batteries

Researchers from Concordia University find way to slow formation of dendrites, currently an obstacle to battery’s use in grid storage

As the demand for more reliable power systems grows in the renewable energy sector, the race is on to develop batteries that cost less but have a longer lifespan.

While zinc-based batteries are safer and more cost-effective than lithium-ion batteries, a major obstacle to their use in large-scale, grid storage is their shorter lifespan. They fail sooner because they develop tiny, tree-shaped metal structures on the anode called dendrites, which cause the battery to short circuit.

Now researchers from Concordia University have found a way to slow dendrite formation. Using the ultrabright X-rays of the Canadian Light Source at the University of Saskatchewan, they found that “sprinkling” a small amount of gold nanoparticles on a battery’s inner surface can cut dendrite growth by up to 50 times compared to regular zinc batteries. Their gold-treated batteries went on to work for more than 6,000 hours in lab settings.

“Coating the electrode is known to improve battery performance, but the small quantity of particles needed for our technique and how they are arranged on the battery surface is a very new, exciting finding,” says Seungil Lee, a PhD student at Concordia and lead author of the team’s paper, published in the Journal of Materials Chemistry A.

Read more on the CLS website

Image: GiSAXS measurements showing arrangements, spacing of gold particles on electrode surface

Thin layer of tin prevents short-circuiting in lithium-ion batteries

Thin layer of tin prevents short-circuiting in lithium-ion batteries

ithium-ion batteries have a lot of advantages. They charge quickly, have a high energy density, and can be repeatedly charged and discharged.

They do have one significant shortcoming, however: they’re prone to short-circuiting.  This occurs when a connection forms between the two electrodes inside the cell. A short circuit can result in a sudden loss of voltage or the rapid discharge of high current, both causing the battery to fail. In extreme cases, a short circuit can cause a cell to overheat, start on fire, or even explode.

A leading cause of short circuits are rough, tree-like crystal structures called dendrites that can form on the surface of one of the electrodes. When dendrites grow all the way across the cell and make contact with the other electrode, a short circuit can occur.

Using the Canadian Light Source (CLS) at the University of Saskatchewan (USask), researchers from the University of Alberta (UAlberta) have come up with a promising approach to prevent formation of dendrites in solid-state lithium-ion batteries. They found that adding a tin-rich layer between the electrode and the electrolyte helps spread the lithium around when it’s being deposited on the battery, creating a smooth surface that suppresses the formation of dendrites. The results are published in the journal ACS Applied Materials and Interfaces. The team also found that the cell modified with the tin-rich structure can operate at a much higher current and withstand many more charging-discharging cycles than a regular cell.

Read more on CLS website