SoCal Tech Focus: Energy Sales

Underwater devices that need portable power, like those used for data logging or to measure conductivity, temperature and depth, face significant challenges. Operating beneath the sea means tidal forces, frigid temperatures and the corrosive nature of the very environment they are immersed in. However, the most daunting of these is the unrelenting effects of seawater pressure. To keep the effects of constant seawater pressure from imploding power cells, battery packs have been placed inside of pressure housings. While PVC housings are used down to 600-ft., other materials such as steel, iron, or for the deepest applications, titanium or advanced composites, can add significant cost to portable power consumables. 

Energy Sales last month unveiled a new approach to pressure tolerance in the field of battery design. Developed for the deep ocean, the PTBS, a pressure tolerant battery system, addresses cost-efficient battery applications that work from 1800 to 3000 m. The design, initially featuring alkaline cells, replaces the need for housings made of costly materials.

“We worked with the University of Washington to identify and design in better cost efficiencies,” said Jean-Michel Bourdon, CEO for the value-added battery specialist firm. “We’ve demonstrated a remarkable cost/performance breakthrough with the PTBS and it played out in all of our testing with UW.”  Because the PTBS uses alkaline cells, he pointed out, the new systems do not require UN transportation testing or certification. “Just one illustration of cost savings.”

The PTBS is designed for untethered applications with long deployments such as data loggers, Sonde devices and bottom pressure recorders like those used on DART II Tsunami detection and warning systems. It operates as deep as 3000m and in temperatures as low as two degrees Celsius. It features a scalable design from 14 to 42 cells resulting in energy output flexibility from 360 to 900 Watt-hours (Wh). In addition, by using alkaline cells, the new system requires no United Nations (UN) transportation testing or certification.

“This pack designed by Energy Sales will reduce our costs for short term applications,” said Chris Siani, Sr. Electrical Engineer at APL/UW. “Load and pressure tests done at my lab show that this battery pack design operates well at pressures up to 4,400 psi (~3,000m), without the need for costly steel or titanium housings. We are looking forward to using this new battery pack in upcoming projects.”

Product Category: Battery Pack

Manufacturer: Energy Sales

RoHS: Not Applicable

Scalable Output Voltages: 3V to 63V

Scalable Capacity: 357 Ah to 17 Ah

Chemistry: Alkaline

Termination Style: Custom

Brand: Energy Sales

Packaging: Individual

Non-Rechargeable

Max. Operable Depth: 3,000m 

Min. Temperature: 35.6°F
 

(As published in the March 2017 edition of Marine Technology Reporter)