Three Ways EchoStat® Enhances Battery Cell Testing While Powering the Drive Toward a Scalable EV Future
March 6, 2023

One of the most frequent questions we’re asked here at Liminal is if we are trying to replace the existing technologies in the world of EV battery cell testing and inspection. With our innovative EchoStat solution — the only production-ready technology that leverages ultrasound technology and machine learning — it may seem like it. 

But in reality, EchoStat overcomes the limitations of conventional testing technologies with richer data, deeper anomaly detection and highly accurate predictive analytics at factory-ready rates. While there is still a critical need for conventional testing technologies like optics, electrical, X-rays and CTs, we offer enhanced inspection at various production points to deliver advanced intelligence and insights that existing technologies cannot deliver. These insights help manufacturers produce safe, reliable EV batteries at scale for a world shifting toward a cleaner energy future.

Here’s how we do it:

1. Richer Data

Cell performance is dependent on electrode fabrication, cell assembly, electrolyte fill and soak, and formation. However, issues that may occur in these process steps are not caught until end-of-line electrical testing, which happens days to weeks after the error actually occurs. Standard electrical tests at the end of the manufacturing line can be fast and cost effective for voltage and resistance tests, but do not correlate well to cell performance.

EchoStat provides manufacturers with rich data insights in real-time. We get spatially resolved 2D data in seconds, and much more accurate predictions of cell performance and better overall insights across the manufacturing process. Additionally, through ultrasound technology, we are able to extract over 60 metrics related to physical features in a cell, which we combine into resulting scores that provide much more specific insights than standard X-ray, visual, or electrical testing.

2. Precise Predictive Analytics

Through acoustic scans, the advanced EchoStat solution is able to take a snapshot of cells before the Quality Assurance/Quality Control stage. That seconds-long snapshot provides data that feeds into unparalleled predictive analytics models. During various in-factory trials with customers on commercial cells, EchoStat’s performance prediction models have predicted cell performance with accuracy ranging from 83 to 98 percent, and our anomaly detection models have identified cells containing separator defects with greater than 90 percent accuracy.

3. Faster Battery Cell Testing and Improved Quality Control

Time is crucial when it comes to manufacturing high-quality, reliable and affordable EV batteries at scale. Standard testing methods can take time to provide detailed accurate results. CT scans, for example, are key for quality, high-resolution 3D images, but can take two to four hours to scan each cell. In line, EchoStat is able to provide measurements in under six seconds per cell, while also having the ability to detect a wider catalog of process anomalies. 

alt= battery cell testing platform from Liminal shows advantages in a matrix table format
How EchoStat® stacks up next to conventional methods

Delivering Safe, Reliable Batteries for a Clean Energy Future

In addition to the above complementary benefits, EchoStat can identify sub-surface or internal issues, whereas standard optical methods are limited to surface-level defects. With EchoStat, manufacturing errors can also be detected closer to when they actually occur, instead of the lag time of days or weeks experienced with end-of-line electrical test methods. This shorter feedback loop enables battery cell manufacturers to increase their line efficiency and yield and reduce production costs. Finally, our technology is able to aggregate data across the production line, from cell finishing to end-of-line QA/QC, which provides unmatched insights to improve process quality monitoring and control. 

There is a paradigm shift in the battery manufacturing industry due to the unprecedented demand from the EV and energy storage industries. Manufacturers see the value in improved testing and inspection as a way to quickly scale up production of high-quality, reliable batteries that will not be subject to costly recalls. The demand for reducing costs and improving the quality of the cells that go into EV batteries is on the rise, and advanced inspection throughout the entire manufacturing process is key to making that happen.

EchoStat can identify errant cells with much more fidelity than ever before to ensure no bad cell leaves the plant and gets into an EV. With its unique technological advantages, EchoStat unlocks value every step of the way, enabling battery manufacturers to meet the rising demand for high quality and cost effective cells.