Using heat and pressure to improve battery manufacture

Oak Ridge National Laboratory scientists found that a small tweak created big performance improvements in a type of solid-state battery, a technology considered vital to broader electric vehicle adoption.

These batteries use a solid electrolyte instead of a potentially flammable liquid. When the battery charges or operates, ions move between electrodes through the electrolyte between them. A new method for pressing the solid electrolyte practically eliminates tiny air pockets that block ion flow, so the battery charges twice as fast.

ORNL lead researcher Marm Dixit said the approach involved heating the press after spreading the electrolyte on it, then letting the electrolyte cool under pressure. The resulting material was almost 1,000 times more conductive. “It’s the same material—you’re just changing how you make it, while improving the battery performance on a number of fronts,” Dixit said.

These results demonstrate a pathway for processing solid electrolytes at an industrial scale while providing unprecedented control over their internal structure for a more reliable battery.

The work is published in the journal ACS Energy Letters.