Researchers at New York University have developed a new technique for imaging the insides of batteries in 3D. The high-resolution imaging allows scientists to watch the batteries charge and discharge in real time.

"One particular challenge we wanted to solve was to make the measurements 3D and sufficiently fast, so that they could be done during the battery-charging cycle," Alexej Jerschow, a professor of chemistry at NYU, said in a news release.

"This was made possible by using intrinsic amplification processes, which allow one to measure small features within the cell to diagnose common battery failure mechanisms," Jerschow explained. "We believe these methods could become important techniques for the development of better batteries."

The new-and-improved magnetic resonance imaging technique helped researchers peer inside rechargeable lithium-ion batteries -- the power source for a variety of electronics, including smartphones, laptops and electric cars.

Scientists have high hopes for lithium-ion batteries, but their potential is currently being held back by dendrites -- deformities which form in lithium metal over time. Dendrites hinder the efficiency of lithium-ion batteries and can even cause the batteries to catch on fire.

Scientists developed the latest imaging method in order to monitor the development of dendrites inside lithium-ion cells, and to understand what kinds of conditions trigger their growth.

When researchers focused their imaging on the batteries' electrolyte solution, which carries charged ions between the two electrodes, distortions appeared in the vicinity of growing dendrites.

"The method examines the space and materials around dendrites, rather than the dendrites themselves," said Andrew Ilott, a postdoctoral fellow at NYU. "As a result, the method is more universal."

Ilott is the lead author of a new paper detailing the novel MRI technique. The paper was published this week in the journal PNAS.

"We can examine structures formed by other metals, such as, for example, sodium or magnesium--materials that are currently considered as alternatives to lithium," Ilott added. "The 3D images give us particular insights into the morphology and extent of the dendrites that can grow under different battery operating conditions."