Could a Composite of Minerals Including Silver Replace Lithium in Batteries?
From Silver News 30 June 2023
Although lithium batteries are the current choice for many applications
– including electric automobiles – because of their ease of recharging
and longer life than traditional batteries, they suffer from several
drawbacks including incidents of combustion and explosion.
Silver may provide some relief, according to researchers at Duke
University in Durham, North Carolina. They have been experimenting
with replacing lithium with argyrodite, a mineral that contains silver as
well as other elements. In fact, the group is using ‘machine learning,’
a branch of artificial intelligence (AI), to quickly simulate other, new
compounds in their quest to find the best mix of chemicals.
The main advantage to using argyrodite is that it allows a battery to be
‘solid state’ meaning there are no electrolyte liquids in the battery as
there is with lithium cells. The liquids make batteries sensitive to high
temperatures which not only cause gradual degradation but can also
produce what engineers classify as ‘thermal catastrophes’ – fire and
explosions.
Olivier Delaire, associate professor of mechanical engineering and
materials science at Duke, quoted in phys.org, said: “Every electric
vehicle manufacturer is trying to move to new solid-state battery
designs, but none of them are disclosing which compositions they’re
betting on. Winning that race would be a game changer because cars
could charge faster, last longer and be safer all at once.” Delaire and his
group are publicly disclosing their compositions.
He noted that a material made of silver, selenium and tin, a type of
argyrodite, provides a stable structure to which silver atoms move
around, which, in turn helps to produce electric current. They also
found, unexpectedly, that the structure bends its shape to let the silver
atoms move even more freely. Delaire said, “It’s sort of like the silver
atoms are marbles rattling around about the bottom of a very shallow
well, moving about like the crystalline scaffold isn’t solid.”
Now that AI has become more commonplace in research, researchers
like Delaire expect his group’s experiments using computer simulations
to move forward faster than were previously thought possible.