How Electric Car Conversion Kits Work

Before we discuss anything else, we need to realize the difference between all-electric cars and gasoline-powered cars. The conventional cars you see on the road run with the help of an internal combustion engine, which is built using a large number of moving parts. These parts are set into motion when gasoline burns, creating energy that moves a series of pistons and rods. The linear motion provided by the pistons and rods is converted into rotary motion at the crankshaft. The rotary motion is transferred through the transmission, driveshaft, differential, axle and eventually the wheels, which makes the car move.

An electric car, on the other hand, has three key elements that set it apart from a typical gasoline-powered car:

An electric motor is significantly different from a gasoline engine for many reasons. Perhaps the most notable of these is that it doesn't burn fuel and it only has one rotating element. The motor runs with the help of a controller, which gets its power from a set of batteries. If a vehicle is a hybrid, which means it operates with both an electric motor and a gasoline engine, the gasoline engine typically charges the batteries while the motor is running. But pure electric cars are plug-in vehicles -- they don't have a gas-powered engine to charge the batteries. They use extension cords and take power from your household or office current.

So while a gasoline engine is a big tangle of pipes and hoses, an electric motor relies heavily on a complex connection of wires. Installing an electric car conversion kit often involves ripping out that tangle, which includes the engine, transmission, gas tank and exhaust system and replacing it with an electric motor, controller and battery array as described above.

Since most people don't have the experience to perform this kind of task, a few companies are offering various kinds of conversion kits that put everything into one neat package. What types of conversion kits are out there? Will they work with any car, or would you have to buy a specific make and model? Do they really work, or are they just expensive add-ons that don't add up to much? Find out on the next page.

There are several different types of electric conversion kits available. Some are meant for specific makes of cars. A company called A123 Systems, for example, began offering the first mass-produced aftermarket electric conversion kit in 2008, the Hymotion L5, a device they call a range extender module. The Hymotion L5 kit is meant specifically for the Toyota Prius, and it turns the popular hybrid car into a plug-in hybrid, the type of vehicle that (to date) rarely makes it past the concept stage. Instead of generating electric power with the help of the Prius's engine, the module can plug in to any 120-volt house current and fully charge within just four hours.

The device essentially adds a much bigger battery to the Prius -- it carries 5,000 watt-hours of electric power, compared to the 1,300 watt-hours the original Prius battery offers. The conversion kit adds to the car's electric range and allegedly bumps the average fuel efficiency from 40 miles per gallon (17 kilometers per liter) to more than 100 miles per gallon (42.5 kilometers per liter).

Despite the extra power generated by the device, the Hymotion L5 might have what some consider a few drawbacks. The first is the price: $10,395 plus applicable taxes. And anyone who wishes to purchase a kit must first pay a $1,000 down payment on A123's Web site. The module also isn't something that the company will simply mail to you with a set of instructions -- you have to visit the nearest authorized dealer for a proper installation -- there are 11 authorized dealers spread out across the United States.

Other conversion kits, like one offered by Poulsen Hybrid (about $3,500) or the Electrocharger by VS Composites (about $4,000), allegedly work with any conventional car, but they typically need to be installed by a mechanic or an authorized dealers, which, of course, costs more money.

Car manufacturers are skeptical about these conversion kits, primarily because despite claims that many of the devices can work with a conventional car, it's uncertain how truly universal these kits are. Parts from a conversion kit could interfere with parts on the original vehicle and cause related systems to fail. On top of this, a new car warranty could become void by adding unauthorized aftermarket parts.

So, before you even think about trying out an electric car conversion kit, it would be best to talk to someone -- particularly an experienced mechanic -- who really knows what he or she is talking about. Unfortunately, many of the conversion kit guides you'll find on the Internet are, for lack of a better term, snake oil.

For more information about electric cars, hybrid cars and other related topics, follow the links the next page.