How Electric Car Conversion Kits Work

Makers of electric car conversion kits claim to be able to convert your gas guzzler into an efficient alternate fuel vehicle. Can you turn your vehicle into an an electric car with just a kit?
Makers of electric car conversion kits claim to be able to convert your gas guzzler into an efficient alternative fuel vehicle.
Nick Daly/Getty Images

Of all of the different types of alternative fuel vehicles available, the electric car has had one of the rockiest histories. Although hybrid cars with gas-electric engines have become popular with drivers looking to save money at the pump while reducing their carbon emissions, mass-produced all-electric cars simply haven't become a reality -- not yet, anyway.

We hear daily reports about how the auto industry is looking into alternative technologies in order to pick up sagging sales, yet electric vehicles only exist as prototypes and concepts at this point. That's not to say that the idea doesn't work. In fact, electric cars actually have a long history that goes all the way back to the early 19th century. Thomas Edison even worked on plans to make an efficient, long-lasting battery that could power vehicles, but he eventually abandoned it. With the introduction of the Ford Model-T, which was powered by a gasoline engine, automobile production was heavily influenced for years to come.


There have been recent examples of all-electric vehicles, including the Toyota Rav4 EV and the Tesla Roadster for instance, but they've proven too expensive or too finicky for mass-production. In 2008, Ford announced hopes to have an all-electric vehicle ready for the market by 2011, but if you're a skeptic and know even a little about the checkered history of electric cars, this announcement may be just that -- a hope, and not a reality [source: Romero].

So, for the moment, you can't just walk into your neighborhood car dealership and drive the latest all-electric model off of the lot. For those passionate about electric cars and the technology behind them, however, some have taken the matter into their own hands. Instead of waiting around for the big car companies to produce electric vehicles, some people have performed electric car conversions by taking a conventional car, one that's normally powered by a gasoline engine, and turning it into an all-electric vehicle.

But what if you don't quite have the technical knowhow to pull off such an endeavor? What are your options? If you do a little searching on the Internet, you might come across advertisements for special electric car conversion kits. The question is, what do these kits do to a conventional gasoline-powered car, and could they really help turn your vehicle into a cleaner, more environmentally-friendly machine? Keep reading to find out.


The Electric Conversion

A close-up of a Renault electric car motor.
Conversions can be tricky endeavors, so electric car conversion kits aim to make the process easier for those without technical and mechanical experience.
David Silverman/Getty Images

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 in place of a gasoline engine
  • A controller
  • An array of batteries

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.


Types of Electric Car Conversion Kits

Although makers of available conversion kits claim to make cars like the Prius pictured above more efficient, there may be additional risks and challenges that come with them.
Although makers of available conversion kits claim to make cars like the Prius pictured above more efficient, there may be additional risks and challenges that come with them.
Tim Boyle/Getty Images

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.


Lots More Information

Related HowStuffWorks Articles

  • Beattie, Rich. "Farewell, Octane. Hello, Volt!" New York Times. Sept. 2, 2005. (March 16, 2009)
  • Chang, Althea. "New Kits Turn Any Car Into a Plug-in Hybrid." (March 16, 2009)
  • Poulsen Hybrid. "Frequently Asked Questions." (March 16, 2009)
  • Public Broadcasting Service. "Timeline: Life & Death of the Electric Car." June 9, 2006. (March 16, 2009)
  • Romero, Frances. "A Brief History of the Electric Car." TIME Magazine. Jan. 13, 2009. (March 16, 2009),8599,1871282,00.html
  • "PHEV (Plug-in Electric Hybrid Vehicle) Conversion Kit." Nov. 2008. (March 16, 2009)
  • Wald, Matthew L. "A Plug-In Conversion for Prius." New York Times. April 27, 2008. (March 16, 2009)