SubCtech has completed full-load electrical testing for a new 600 V-class underwater platform battery system, successfully demonstrating 50 kW of unthrottled continuous power output for over 50 minutes.
The test results exceeded the customer’s minimum runtime requirement of 45 minutes by more than 11 percent under constant electrical load at an operating temperature of 35 °C. Developed under a dedicated project for a high-voltage, high-discharge-rate underwater system, the technology features a nominal voltage of approximately 600 V and a total energy capacity exceeding 40 kWh. Throughout the test duration, the battery sustained full output power without relying on thermal throttling or power limitations.
Rather than implementing entirely new battery chemistries, engineering teams achieved the power surge by scaling SubCtech’s established technology platform, which previously delivered continuous outputs up to 35 kW. The achievement marks both the first 50 kW continuous power demonstration for the company’s autonomous underwater vehicle (AUV) architecture and its entry into the 600 V-class market segment.
Stefan Marx, subCtech CEO, commented, “For the first time, we have demonstrated the truly enormous performance of 50 kW continuous power from an AUV battery system. And we achieved this based on our proven technology, without having to introduce fundamentally new technologies. The test even ran for more than 50 minutes instead of the required 45 minutes. Under these conditions, this is an outstanding result and a major achievement for the entire team.”
Engineers designed the architecture to balance energy density, power delivery, thermal control, and system integration within space-constrained subsea environments. Leveraging existing platform designs allowed the team to increase output voltage and current handling while maintaining the system reliability required for deepwater deployments.
Marx added, “But with the best team – and by that I mean everyone at SubCtech – we had absolute confidence that we could deliver. This result once again confirms our position as a leading global supplier of high-performance underwater battery systems.”
The project will next transition to Factory Acceptance Testing (FAT) at SubCtech’s facilities, followed by customer On-Site Acceptance Testing (OSAT) in the autumn. Subsequent milestones include comprehensive environmental and electromagnetic qualification against MIL-STD-810G and MIL-STD-461E/F standards, validating system performance across shock, vibration, humidity, temperature extremes, and electromagnetic compatibility.
