Recently acquired by major tech firm L3 Technologies. Now MIT spinout Open Water Power (OWP) aims to greatly improve the range of unpiloted underwater vehicles (UUVs). OWP has developed a novel aluminum-water power system that’s safer and more durable. That gives UUVs a tenfold increase in range over traditional lithium-ion batteries used for the same applications.
The power systems could find a wide range of uses, including helping UUVs dive deeper, for longer periods of time, into the ocean’s abyss to explore ship wreckages, map the ocean floor, and conduct research. Also used for long-range oil prospecting out at sea and various military applications.
OWP is currently working with the U.S. Navy to replace batteries in acoustic sensors designed to detect enemy submarines. This summer, the startup will launch a pilot with Riptide Autonomous Solutions, which will use the UUVs for underwater surveys.
Currently, Riptide’s UUVs travel roughly 100 nautical miles in one go, but the company hopes OWP can increase that distance to 1,000 nautical miles.
Drinking Sea water for power
Most UUVs use lithium-based batteries, which have several issues. So, UUV-sized batteries are generally not shippable by air. Recharging the batteries as necessary. And the batteries encased in expensive metal pressure vessels.
In contrast, OWP’s power system is safer, cheaper, and longer-lasting. It consists alloyed aluminum, cathode alloyed with combination of elements (primarily nickel), alkaline electrolyte positioned between the electrodes.
UUV equipped power system placed in ocean, sea water is pulled into battery, and split at cathode into hydroxide anions and hydrogen gas.
The hydroxide anions interact with the aluminum anode, creating aluminum hydroxide and releasing electrons. Those electrons travel back toward the cathode, donating energy to a circuit along the way to begin the cycle anew. Both aluminum hydroxide and hydrogen gas dropped as harmless waste.
Components are only activated when flooded with water. Once the aluminum anode corrodes, replaced at low cost. Think of the power system as type of underwater engine, where water is the oxidizer feeding the chemical reactions, instead of the air used by car engines.
In addition, Power system uses a pump to circulate the electrolyte, scooping up unwanted aluminum hydroxide on the anode and dumping it onto a custom precipitation trap. Saturated, traps with waste ejected and replaced automatically.
The electrolyte prevents marine organisms from growing inside the power system.