Solid State lithium batteries are often preferred to liquid or gel based batteries. They are more stable (safer) and can hold a charge for longer, so whether you're using a cell phone or driving an EV that extra long charge will come in handy. 

The downside is that they are difficult to recycle, making them environmentally unfriendly. 

This new research from a team at Penn State University could clear a path to more efficient recycling, and the recycled battery maintains as much as 92% of the power of the original material. 

The research is still new, but it provides a glimpse of what's to come: safer, longer-lasting, more sustainable battery power.