Solid State Batteries!!

The invention of lithium-ion batteries did bring a revolution in the history of mankind. For more than 20 years, we are using Li-ion batteries in our electrical appliances and there’s no sign of pausing operations anytime soon. However, lithium batteries have also been thrashed by criticisms due to safety issues. These batteries are highly flammable and many accidents due to such batteries have been reported. At times like this, we look for other options. One viable alternative is solid-state batteries which are much safer and energy-dense than our traditional Li-ion batteries. Like the name says, solid-state batteries use a solid ceramic electrolyte instead of a liquid one to conduct the flow of electrons. Using a solid electrolyte reduces the size of batteries significantly and removes the risk factors involved with liquid electrolytes.

But that quest has been beset with one big problem: dendrites. Dendrites are projections of metals that build up on the lithium metal surface that penetrates through the solid electrolyte disrupting the battery structure and ultimately reducing its longevity. The cause of this unnatural phenomenon has been unknown so far and thus solid-state batteries haven’t seen the day of light yet. But things are going to change! Research conducted by MIT scientists has been able to explain the reason behind dendrite formation and how can we divert them. We will get into the details in a bit but first, let’s learn a little more about dendrites. For years we have been trying to replace the graphite-based anode in lithium-ion batteries with solid lithium metal. This would double the cell’s charge storage capacity and make the whole process more energy efficient.

But there’s a major problem in doing so. While charging, lithium metal gets deposited on the anode forming long spike-like projections called dendrites. These dendrites can grow long enough to reach the other side and cause a short circuit which can even lead to a fire.

Credit Tesla Domain