http://www.digitaljournal.com/tech-and-science/technology/freezing-lithium-batteries-makes-them-safer/article/491569

Freezing lithium batteries makes them safer

Posted May 1, 2017 by Tim Sandle
Researchers have used a process called ice-templating to control the electrolyte structure in lithium batteries. The process is non-flammable, non-toxic and flexible, and leads to longer battery life.
BEWARE: The lithium  button battery  is quite small and easily swallowed by young children.
BEWARE: The lithium "button battery" is quite small and easily swallowed by young children.
Via YouTube
The process has been developed by Professor Yuan Yang from New York’s Columbia Engineering. The aim as to develop a method to create lithium batteries that are safer, with a longer battery life, and which are also bendable. Such a battery could be used in the production of flexible smartphones.
The method, Laboratory Manager reports, uses a process called ice-templating. This allows the structure of the solid electrolyte for lithium batteries to be controlled. Such batteries are the mainstay of portable electronics, electric vehicles, and grid-level energy storage.
Ice templating, also known as freeze casting, is a shaping route for macroporous materials. Over the past 15 years, it has been widely applied to various classes of materials, and in particular ceramics. Prior to the new research ice tempting had not been used to produce a flexible solid electrolyte for batteries.
The process is not only designed to render batteries flexible there is also a safety feature. Liquid electrolyte is highly flammable; for example, there have been safety issues with some laptops and other electronic devices. To overcome this, the researchers supplemented a solid electrolyte for the liquid electrolyte commonly used to produce solid-state lithium batteries.
READ MORE: Are liquid metals the future of electronics?
For the process the scientists cooled the aqueous solution with ceramic particles and allowed the ice grow. The forming ice pushed away and concentrate the ceramic particles. Following this the researchers applied a vacuum to transition the solid ice to a gas, which resulted in a vertically aligned structure. At the end of the process the researchers added the ceramic structure with a polymer, which provided mechanical support and flexibility to the electrolyte and provided a fast highway for lithium ions.
Tests on the batteries not only showed them to be safer and flexible, the battery density also increased, adding additional power in the region of a 60 percent increase. The tests will lead to further development work.
The study research has been published in the journal Nano Letters. The research paper is titled “A Flexible Solid Composite Electrolyte with Vertically Aligned and Connected Ion-Conducting Nanoparticles for Lithium Batteries.”