The research presented herein intends to improve the flexibility of underwater gliders with the development of a novel propulsion system. The proposed Chemical Buoyancy Drive is indicated to yield up to 20 times the amount of available electric energy and exhibit 90% propulsion efficiency, compared to that of the commercial underwater glider "Spray" at a depth of 1,500 m. Its performance is readily optimised to any depth, and there is no need for a thermal incline in the operational environment. The need to isolate the energy storage from external pressure is eliminated by the use of lithium...