Navico Fathom e-Power

Fathom e-Power makes auxiliary electrical power easier.

Navico Fathom e-Power schematic
Fathom serves as an integrated auxiliary power system that includes monitoring and control via a mobile app. Courtesy Navico

Special deliverySign up for the free Boating email newsletter. Subscribe to Boating magazine for $14 for 1 year and receive 4 bonus digital issues.

Fossil-fuel marine generators have long served the AC electrical needs of boaters while away from shore power. But let’s face it, gensets can be finicky, are high-maintenance and smelly, and create intrusive noise and, in some cases, dangerous CO emissions. Navico aims to shift that paradigm with its Fathom e-Power system.

At its heart, Fathom e-Power uses advanced lithium-battery technology to provide auxiliary electrical power for boats ranging from less than 20 feet in length to yachts. “Lithium batteries for marine applications have gained substantial traction in the last decade,” says Eric Lindquist, VP and general manager for power systems at the Navico Group. “They last longer, charge faster, reduce weight and maximize space, as well as save time and money in the long run (versus lead-acid batteries)—all the while minimizing negative impacts on the environment.” The upshot: Lithium battery systems are well on the way to rivaling marine generators as an auxiliary power source.

Yet Fathom e-Power extends well beyond batteries. It is designed to seamlessly integrate a host of onboard components from brands within Navico (a Brunswick company), including BEP, CZone, Ancor, Blue Sea Systems and Simrad, as well as Mastervolt lithium-iron phosphate (LiFePO4) marine batteries and chargers. The system will also integrate available high-capacity alternators on engines, such as the new 350 and 400 hp V-10 Verado outboards from Mercury, also a Brunswick company.

“Navico Group’s portfolio of diverse products and brands puts us in a unique position to deliver advanced integrated technologies like the Fathom e-Power system,” says Brett Dibkey, Navico Group president. “The enhanced Fathom system provides reliable power management and control, allowing users to better understand and manage their power needs.”

The system allows boaters to extend their time away from the umbilical of a shore-power cord and enjoy electrical luxuries in a remote anchorage or other locale without relying on a generator, Dibkey says.

Read Next: Installing a Lithium Battery System

Simrad MFDs
Navico’s Fathom e-Power system also networks with Simrad multifunction displays for onboard monitoring and control. Courtesy Navico

How much power would be available? Could you, for instance, run all onboard electrical loads for four hours? On the Sea Ray 400 SLX OB with the available 24 kWh 48-volt Fathom battery bank, it’s possible to maintain use of all onboard systems for four hours, but Navico doesn’t recommend it. Yet the company says boaters with a lighter, more normal electrical load wouldn’t need to worry about draining the battery bank over a four-hour period.

An intuitive user interface allows boaters to easily monitor power consumption and control the system via multifunction displays or smart mobile devices. An easy-to-understand report on battery status, including a “time to empty” indicator, enables boaters to make informed decisions regarding onboard energy reserves. Boaters can also set alerts and reminders to recharge batteries based on custom preferences.

Some models within the Brunswick Boat Group are already incorporating the Fathom e-Power system as original equipment, most notably models in the Boston Whaler and, as mentioned previously, Sea Ray lineups. To learn more, visit

More Boats