We've seen BMW i3 battery power used for four-wheel, two-wheel and home power applications, and now it makes a move off land. BMW i has teamed with German electric boat motor specialist Torqeedo in adapting the i3 battery to the Torqeedo Deep Blue line, Torqeedo's most powerful electric boat powertrain, which comes in 40- and 80-hp varieties.
Torqeedo highlighted the new i3 battery system at the Boot Düsseldorf show, which wrapped up yesterday. It seems quite convinced that it's the future of electric boat motoring, explaining that the new battery offers a 40 percent higher energy density for a lower watt-hour cost. It also explains that the prismatic cell design allows for combination of compact size, efficient cooling and even temperature distribution within the battery.
The tough-built i3 batteries also ensure the rugged, shock-resistant performance needed for boating applications. They are IP67 waterproof and include a pressure release safety disc for releasing built-up gases while maintaining waterproof integrity.
The Deep Blue i 1800 rpm inboard powertrain with the BMW battery joins several Volvo Penta engines on the Nimbus 305 Drophead's options sheet, creating the 305 Drophead E-Power. Top speed information for the 305 Drophead E-Power is not yet listed, but it is certain that the Deep Blue electric drive will allow the boat to navigate through the water quietly, without emissions.
The newest 305 borrows more than just its batteries from the automotive industry, its name derived from the "drophead" convertibles of British motoring. The airy 33-foot (10 m) day cruiser looks like a beautiful way to enjoy the open sea under sunny blue skies. The vessel carries up to eight people and sleeps up to six with a combination of owner's cabin, side cabin and convertible dinette. The two cabins share the head and shower.
The open cockpit area and aft deck invite passengers to relax with a six-person wraparound sofa, integrated bathing platform, four-person dinette, and wet bar with sink, refrigerator and space for a microwave, electric grill or stove. A powered fold-out canvas roof covers the entire cockpit area at the push of a button, and available wall panels provide wraparound protection from the elements as needed. There's a sun bed on the foredeck, and Nimbus explains the boat's "sidewalk design" makes it easy to move around the deck.
The 305 Drophead's "Smart Speed" vacuum-infused laminate hull is designed to optimize comfort and fuel economy at all speeds, 0 to 22 knots (0 to 40.7 km/h).
"Some people like to drive fast when they're at the
helm, but very few like it when traveling too fast at
sea," explains Nimbus head designer Joacim Gustavsson. "The central idea of this model is for all those
aboard to enjoy themselves and socialize during the
trip and under the open sky."
In addition to introducing the E-Power variant this month, Nimbus put the entire 305 Drophead lineup on sale, after first revealing it last March. For those that prefer diesel power, the boat can be equipped with 109-hp, 148-hp or 220-hp Volvo Penta engines. Nimbus did not respond to our email requesting pricing, battery capacity and electric range information before publishing time, but we will update the article if it does.
Update: Nimbus got back to us about performance and pricing. The 305 Drophead E-Power starts at SEK 1,852,700 (approx. US$212,000) and comes standard with a 32-kWh BMW battery. Buyers can also choose the option of dual 32-kWh batteries. Cruising speed is 5 to 6 knots (9 to 11 km/h) and theoretical range at those speeds is roughly between 15 and 24 nautical miles (27.8 to 44.4 km) with the standard 32-kWh battery and double that with the dual-battery system.