The US takes an important step towards batteries of the future

The US takes an important step towards batteries of the future

Researchers at the US Department of Energy’s Oak Ridge National Laboratory have created a new polymer electrolyte that could address one of the central challenges facing solid-state batteries: ions move far too slowly through the material.

The main difficulty with solid-state batteries is that ions must travel through a solid electrolyte, yet many such materials are either excessively brittle or inefficient at conducting charge. ORNL’s new polymer material, by contrast, combines the flexibility of polymers with exceptionally high ionic conductivity. The scientists say that, in a particular configuration, ions can move billions of times faster than the material’s surrounding structure.

The effect depends on precisely tailoring a lithium-salt-based polymer and introducing specialised molecular groups known as bipolar ions. These form more polar regions within the material, producing small “ion pockets”. At the right concentration, the pockets link up to create channels that allow ions to pass through the electrolyte quickly and with minimal resistance.

The researchers believe the finding could represent an important advance towards more reliable solid-state batteries. The team next intends to investigate the polymer’s operating mechanism at the molecular level using supercomputers and artificial intelligence.