The basic concept is pretty simple - an electric motor powered by a battery bank turns the propeller. The boat's speed is adjusted with a controller that can be used to vary the motor speed. The efficiency of the motor can be improved by using gears between the motor and the propeller. There are many more variations, but this is the basic system used by all electric boats.

Lithium Ion Power Tools

The battery bank is mostly made up of the usual lead acid batteries. Lithium ion batteries and fuel cells are also being used on an experimental basis, but have yet to be made commercially viable on a mass-scale. Whatever the battery type, every electric boat always has a charger and charge regulator to ensure the battery doesn't overcharge.

Lithium Ion Power Tools

The electric motor is usually a DC motor. It can be field-wound or the permanent magnet type. The advantage of using DC motors is that they don't require high voltages, so it is a lot safer and needs less insulation. Also, DC motors offer a choice between electronic and mechanical controllers, while AC motors necessarily need electronic controllers.

The simplest setup has the motor using a propeller shaft to power the propeller. If gears are required, it can be a common gear box or coaxial gears. In order to reduce noise, transmission belts are often used instead. The whole setup, including the motor and propeller, are often part of a system at the back of the boat. In this case, it is known as an outboard motor.

There are no carbon emissions or exhaust to speak of. Unlike an internal combustion engine that runs on diesel, an electric boat is not harmful to the environment. Another big advantage is that an electric powered boat makes comparatively very little noise. Even this little amount of noise can be reduced to almost nothing by using sound-proofed boxes and anti-vibration mountings.

The eco-friendly advantage can be further enhanced by using renewable shore energy or solar power. The only difference is that onboard solar panels mounted strategically on the boat charge the batteries, instead of having them charged using shore power. To be noted that commercial boats that have a daily schedule cannot depend solely on solar power, so these are hybrids called 'solar-assisted' which combine solar power and fuel.

While electric boats are still mostly restricted to inland waterways, there is a huge amount of ongoing research in this field. Solar and wind turbine powered boats are being built to cross the oceans. Batteries are being developed that need less charging and do not have to be refilled. The day is not far when large ships with thousands of passengers and crew will run entirely on clean electric power.

Electric Boat History, Technology and The Future

Lithium Ion Power Tools

Black Friday Makita Bare-Tool BJV180Z 18-Volt LXT Lithium-Ion Cordless Jig Saw 2011 Deals

Nov 16, 2011 07:53:37

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Black Friday Makita Bare-Tool BJV180Z 18-Volt LXT Lithium-Ion Cordless Jig Saw Feature

Makita-built variable-speed motor delivers 0-2,600 strokes per minute for fast, efficient cutting
Three orbital settings plus straight cutting for use in a wide range of materials
Includes built-in LED light to illuminate the work area
LXT lithium-ion battery, Energy Star-rated 30-minute rapid optimum charger produce 430% lifetime work
Tool only (battery not included), three-year warranty

Black Friday Makita Bare-Tool BJV180Z 18-Volt LXT Lithium-Ion Cordless Jig Saw Overview

The Makita BJV180Z is an 18V LXT Lithium-ion cordless jig saw kit. It has 4-pole position cut settings (3 orbital and 1 straight) for fast and efficient cutting in all applications. The Makita BJV180's large variable speed trigger allows for total cutting control (0-2600 SPM). This is a tool only, it does not come with batteries or a charger.

Black Friday Makita Bare-Tool BJV180Z 18-Volt LXT Lithium-Ion Cordless Jig Saw Specifications

Makita's 18V LXT Lithium-Ion Cordless Jig Saw seamlessly combines precision and power with the lowest overall weight in its class. The BJV180Z has a range of precision and comfort features for precise jig saw cutting performance, including less vibration and lower noise for more control and comfort.

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BJV180Z Features

COMFORT - Only 6.1 lbs. with ergonomic grip

CONVENIENCE - Large trigger switch, built-in L.E.D. light and "tool-less" blade change

PERFORMANCE - LXT Li-Ion batteries charge in 30 minutes, run longer and deliver 2.5X more cycles

Battery and charger not included

Tool Specifications

Length of stroke	1"
Max. cutting depth	Wood (5-5/16"), Steel (3/8")
Strokes per minute	0-2,600 SPM
Battery	18V LXT Lithium-Ion
Overall length	10-1/8"
Net weight	6.1 lbs. (w/battery)

Makita-Built Motor Engineered for Versatile Power
The BJV180Z features a Makita-built high-torque motor that produces a 1-inch stroke and 2,600 strokes per minute (SPM) for fast and efficient cutting. In addition, the BJV180Z has lower vibration and less noise for more control and comfort. The BJV180Z has four position cut settings (three orbital and one straight) for fast and efficient cutting in all applications, and the "tool-less" push-in lock system for quick blade changes. The blade roller guide is positioned close to the work piece for precision accuracy in straight and bevel cuts.

Ergonomic Design in a Compact Size
The BJV180Z weighs just 6.1 pounds (with battery, sold separately) with a more compact design at 10-1/8 inches long and an ergonomic shape that fits like a glove for reduced operator fatigue. The two-finger variable speed trigger switch is easy to handle, even with a gloved hand. BJV180Z is also equipped with a built-in L.E.D. light that illuminates the work area for more efficient work.

Versatile Design for a Range of Applications
The BJV180Z has less noise, less vibration and less weight for more control and comfort. It is engineered for professional woodworkers, cabinetry makers, specialized residential construction workers, and any pro-contractor who requires a best-in-class engineered cordless jig saw. The BJV180Z is just another example of Makita's commitment to innovative technology and best-in-class engineering.

About Makita's 18V LXT Lithium-Ion Cordless Tool Series
As one of the pioneers driving the cordless tool revolution, Makita changed the game with its breakthrough 18V LXT Lithium-Ion Cordless Series. Three years after its debut, Makita's LXT Series has grown from seven to over 35 tools, providing a wide range of cordless solutions for professional tradesmen. Makita also added 18V Compact Lithium-Ion for cordless power in a more compact size.

About Makita
Makita is a worldwide manufacturer of industrial quality power tools, and offers a wide range of industrial accessories. Makita applies leading-edge innovation to produce tools that are stronger, lighter, more powerful and easier to use. Makita USA, Inc. is located in La Mirada, California, and operates an extensive distribution network located throughout the U.S. For more information, please call 800/4-MAKITA (800/462-5482) or visit the website at makitatools.com. Makita is Best in Class Engineering.

Warranty
Every Makita Lithium-Ion tool is backed by Makita's 3-Year Warranty that covers repair due to defects in materials or workmanship up to three years from the date of original purchase. Makita Lithium-Ion batteries and chargers have a limited 1-year warranty. Please see makitatools.com for complete details.