SubCtech Demonstrates 50 kW Continuous Power in AUV Battery System

SubCtech has achieved a major technical milestone by demonstrating 50 kW of continuous power from a 600 V-class battery system for an underwater platform. During a full-load test, the system delivered the required power for more than 50 minutes, exceeding the customer's 45-minute minimum by over 11 percent. The achievement marks the first time the company has demonstrated 50 kW continuous output from an autonomous underwater vehicle battery, while entering the 600 V-class battery segment for the first time.

 

The Technical Achievement

 

SubCtech has reached a significant milestone in underwater battery development. The company achieved this for a customer-defined underwater platform. The project required a battery system delivering 50 kW of continuous power. This output had to be sustained for a minimum of 45 minutes. The system was also required to operate at a temperature of 35 degrees Celsius.

The system's specifications reflect its high-performance design. It features a nominal voltage of approximately 600 V. Its nominal energy capacity exceeds 40 kilowatt-hours. These figures place the system firmly in the high-voltage battery category. This positions it for demanding underwater platform applications.

 

Results of the Full-Load Test

 

The test results exceeded the customer's requirements on key measures. During the electrical full-load test, the system delivered 50 kW continuously. It sustained this output for more than 50 minutes in total. This exceeded the customer's minimum requirement of 45 minutes by more than 11 percent. The additional runtime demonstrated a comfortable margin over the specification.

A critical aspect of the test was the constancy of the load. The full-load test was conducted at a constant load throughout its duration. This was a specific requirement set by the customer. The system was not throttled or power-limited due to temperature constraints. Maintaining full output without thermal limitation was central to the test's success.

 

Significance for SubCtech

 

The achievement represents several firsts for the company. It marks the first demonstration of 50 kW continuous output from its AUV battery systems. This is a substantial step beyond the company's previous capabilities. At the same time, the project marks its entry into the 600 V-class battery segment. Both milestones expand the company's technical reach.

The result validates the scalability of the company's battery architecture. It demonstrates the capability to scale to higher voltage and power levels. This scaling was achieved while maintaining high standards for underwater applications. Company leadership described the enormous performance of 50 kW continuous power. The chief executive characterised the outcome as a major achievement for the entire team.

 

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The Development Approach

 

The company achieved the result through evolution rather than reinvention. At the project's start, its technology had demonstrated up to 35 kW continuous power. The new requirement called for a substantial increase to 50 kW. It also required a nominal system voltage of approximately 600 V. This represented a significant step up in both power and voltage.

The engineering team met these demands using established technology. Rather than adopting fundamentally new battery technologies, they optimised the existing platform. They further developed the company's proven technology to reach the required performance. This approach combined innovation with a high degree of technological maturity. Such maturity is valued by customers requiring reliable, predictable performance.

 

The Demanding Operating Environment

 

The achievement is notable given the constraints of underwater platforms. Such environments demand high energy density alongside strong power capability. Effective thermal management is equally essential in these conditions. Reliability and system integration must also work together seamlessly. All of these factors must function within a highly constrained system architecture.

Meeting the constant-load requirement was particularly demanding in this context. The customer required full electrical load to be maintained throughout the test period. The system had to deliver this without thermal throttling or output reduction. The successful test confirmed the battery could sustain 50 kW under these conditions. This demonstrated the system's robustness in a challenging operating environment.

 

Next Steps in the Programme

 

The successful test marks a milestone rather than the project's conclusion. The programme continues toward further validation stages. The next major step will be the Factory Acceptance Test at the company's facilities. Following this, the system will undergo on-site acceptance testing at the customer's location. This is scheduled to take place in autumn.

The programme also includes rigorous qualification testing. The system will be qualified against demanding environmental and electromagnetic requirements. This includes testing to MIL-STD-810G and MIL-STD-461E/F standards. These cover environmental robustness, shock, vibration, temperature and humidity. Electromagnetic compatibility forms a further area of the qualification programme.