Tag: dendrites

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