Liminal Insights Sees Inside Batteries with Ultrasound to Improve Performance

Liminal Insights (formerly Feasible, Inc.) makes hardware-software systems that measure performance and predict degradation in batteries with a unique combination of ultrasound and data analytics. Its system, EchoStat, is an inspection technology that could help electric-vehicle (EV) battery manufacturers significantly reduce production costs for many types of batteries. Because the ideal battery pack consists of a number of linked cells, its performance depends on how identical the cells are to each other. Liminal Insights has found acoustic testing to be a better predictor of battery cell “sameness,” allowing manufacturers to make cheaper, more reliable products.

Manufacturers currently determine battery condition and predict battery life mainly by running electrical tests, but due to the limitations of these methods, EV manufacturers must overbuild battery packs by 20%-30% to ensure safe and reliable performance. Liminal Insights’ system “sees into” the structure of batteries via ultrasound during battery production. It reduces the need for overbuilding the packs and thereby allows EV makers to design smaller and increase profitability.

The “cell finishing” process, which occurs during cell manufacturing, is very challenging to improve as there are currently no methods that deliver the insights required for effective process monitoring and control at scale. The information gathered from Liminal Insights’ EchoStat platform will enable cell manufacturers to improve process times, production yields and overall product quality and consistency, which all act to decrease the average cost of battery cells. This type of battery testing is the first of its type to be done at NREL.

About the Company

Since 2015, Liminal Insights’ technology has been under development as a part of the U.S. Department of Energy’s Advanced Research Projects Agency-Energy program, as well as the Cyclotron Road incubator at Lawrence Berkeley National Laboratory. As a part of its selection for the Shell Game Changer Accelerator Powered by NREL, Liminal Insights will be testing its battery-degradation prediction model at NREL starting in 2019.

Liminal Insights’ “battery inspection platform delivers unique insights across the value chain, from R&D to full scale production to when the batteries are actually being used in the field,” says CEO Andrew Hsieh.

Liminal Insights’ system addresses a need in the enormous future market for EV batteries. Designing and building lower-cost cells and longer-lasting packs is critical for the success and growth of the multi-billion dollar battery industry as well as the global transition to a low-carbon transportation system.

“Measuring battery degradation, we usually look at conventional testing methods: current, voltage, temperature,” says NREL researcher Ying Shi, who will be leading the research at the lab. With Liminal Insights’ methods, “these extra measurements will help us develop a model to predict degradation.”

Not only is the opportunity to work with Shell exciting, says Hsieh, but the technology itself has links to the history of oil and gas development.

“A lot of our inspiration comes from traditional oil and gas geophysicists – they used sound to understand the structure of rocks,” he says.