Our Origin: Challenging the "Black Box" of Battery Health
ReJoule was founded on a simple but critical observation: in our rapidly electrifying world, the battery remains a "black box." Our CEO, Steven Chung, first encountered this problem during a graduate school project focused on forecasting battery health. He discovered that even the most advanced models failed to deliver consistent, real-world results. When he sought a better way, industry experts simply told him, “that’s just how it’s done.”
Steven realized that this lack of transparency was more than just a technical hurdle—it was a massive environmental and economic bottleneck. As cars, trucks, and homes increasingly depend on battery power, treating a battery as a disposable, unobservable asset is dangerously wasteful. He envisioned a future where every battery’s remaining value is known, verifiable, and utilized to its fullest extent.
The Breakthrough: Lab-Grade Precision at Unparalleled Speed
After graduating, Steven partnered with his sister, Zora Chung (CFO), to turn this vision into reality. Together, they founded ReJoule to bridge the gap between complex laboratory techniques and the messy reality of field operations.
The core of ReJoule’s innovation is a patented design that miniaturizes and scales High-Voltage Electrochemical Impedance Spectroscopy (EIS). While traditional battery testing requires 6 to 24-hour charge/discharge cycles—which are energy-intensive and operationally slow—ReJoule’s BattScan hardware provides a comprehensive health diagnostic in just 10 minutes.
Coupled with our BatteryDB software platform, we translate complex impedance data into a clear, actionable State of Health (SOH) grade with >98% accuracy. This breakthrough provides the data infrastructure necessary to de-risk the entire battery lifecycle, helping our customers reduce the cost of reuse, remanufacturing, and repurposing.
Building a Circular Battery Economy
Today, ReJoule is more than just a diagnostics company; we are an enabler of the circular economy. Our technology is already being used to:
Streamline Automotive Remanufacturing: Helping OEMs and salvage partners identify which battery modules can be repaired rather than scrapped.
Unlock Second-Life Applications: Validating used EV batteries for use in stationary energy storage, such as our project powering the American Museum of Ceramic Art in Pomona, CA.
Secure the Supply Chain: Reducing the need for virgin mineral mining by ensuring that every watt-hour of existing battery capacity is utilized before recycling.
Our Vision & Community Commitment
Headquartered in California, ReJoule is proud to be part of the state’s vibrant cleantech ecosystem. We have secured over $16M in funding and executed paid pilots with four of the top 10 global automakers. As we scale, our goal is to turn our rapid diagnostic method into the global "de-facto" standard for battery grading.
We are committed to building a sustainable future that is both technologically advanced and operationally practical. By providing the "ground truth" for battery health, ReJoule is ensuring that the transition to clean energy is as efficient, safe, and transparent as possible.
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