Build an Electric Car
Having an electric car can save you money on gasoline and can be good for the environment. You can build an electric car using a traditional car. Here are the steps to follow when you want to know how to build an electric car.
Steps
- Choose a car for your electric car conversion.
- It is best to choose a traditional car to use for your conversion. A traditional car would be one that is not too exotic or complicated. A car that you can easily find replacement parts for is ideal. Look for something lightweight since they will run better on an electric battery than a bigger vehicle will. The best choice would typically be a two seater vehicle or otherwise, that weighs under 2000lbs.
- If you're looking to go even faster with your electric car, its also best to choose something with a streamlined aerodynamic rounded body for minimal drag. Headwinds can typically rob your electric vehicle of {{safesubst:#invoke:convert|convert}} of top speed.
- A car with a manual transmission is better for an electric car since cars with electric motors do not necessarily need a transmission. A manual car uses a controller rather than a transmission to make the car run backwards and forwards. In addition a manual transmission will have all the important things your vehicle will need to run safely on the road. Such as a speedometer cable, so you know how fast your going, and a reverse switch that lights the rear tail lights up when you're backing up.
- The car you choose should also have enough room for an electric battery; you will need enough voltage to power the engine you choose. You will want to be able to access the battery easily for any maintenance. You will also need to be able to secure the battery down while distributing the weight evenly in the car. Weight distribution is very important for handling on the road.
- Select a motor for your car that you can assemble on your own.
- Look for something that will not require professional work. A DC motor with diminutive body is the standard motor for an electric car conversion. DC electric motors used for conversion are typically electric forklift dc motors. More often than not, you will find these motors in used condition, but rebuilding them is as simple as sliding the casing off and cleaning and degreasing the motor then rebuilding its connectors.
- Purchase a battery for your electric car.
- You will need a primary and a backup battery before starting to build the car. Look for a gel-cell battery, which is a type of valve-regulated lead-acid battery (VRLA) battery that contains gelled electrolyte. A VRLA battery does not require additional water to the cells. It is a sealed battery with a safety pressure relief valve. You can check with an electric car retailer for the parts you will need.
- The other option, which can be more expensive is to purchase lithium ion batteries. Though these batteries are expensive, they do come in a variety voltages and amps that allow you to buy practically one battery for your entire set up or you can wire together a number of smaller ones like you would end up doing with the gel-cell batteries.
- The average battery needed to pull a large vehicle with passengers and get a decent range would need to total out to 72volts and 40 to 60 amp hours. If you want the vehicle to break {{safesubst:#invoke:convert|convert}} and be something that could handle driving on the free way, it's best to go with 144volts and around 80 amp hours. This is typically where most electric car builders end up purchasing lithium ion batteries due to the size and weight of needing 12 large and heavy gel-cell batteries.
- Remove the old motor and battery parts from the car.
- You will need to use an engine crane and a breaker wrench also known as a cheater bar to help you remove the old parts from the car. Work slowly at tight or rusted bolts. It helps to use liquid wrench and a process of loosening and tightening to free the threads.
- Take out the engine and anything else that is gas related: tank, exhaust, radiator etc. Leave in the things you will need like brakes, horn, fuse pane, transmission, half-shafts and engine sub-harness.
- As far as power steering goes, hopefully the car you chose doesn't have power steering as the new electric engine only has one output shaft and that mates to the transmission, meaning you can not run any accessory pumps such as power steering. If your vehicle has power steering you will need to cut the return and pressure line at the top on the rack and pinion then loop them in together using a double ended brass barb and hose clamps. Be sure to top off as much power steering fluid as possible into the lines before looping them closed. This will turn any power rack and pinion to a manual rack and pinion.
- Install the electric motor and battery where the old ones were. You will need a custom motor mount for the electric motor but you can reuse the transmission mounts. With the electric motor coupled to the transmission and propped on a jack, measure the difference between the old engine motor mount and the electric engine mounting bolts.
- You can make and mount an entirely new mount but it's a lot easier to use the original motor mount as it has dampeners built into it to avoid engine shock. This reduces shakes and rattles when the engine is accelerating or decelerating. Once you have the mount measured out, bring the motor and the old engine mount to a machine shop, they can fabricate the rest.
- You will also need an adapter plate to connect the transmission to the new electric engine and either a coupler or custom designed flywheel to mate the motor's driveshaft to the transmission. It's best to bring the motor and transmission to the machine shop or use a simple piece of cardboard to trace the transmission bolt holes on one side and the electric engine bolts on the other.
- Place the electric motor inside the front of the car and mount the controller. The controller can typically be found as a common 72volt controller on any high end golf cart, however if you want a 144volt controller of higher, you will need to find websites that sell these items especially for electric car conversions.
- Install the battery as well, using brackets to hold the batteries. Connect the motor and batteries to the controller using EV 00 or 0 gauge cables, these can bought by the foot at car stereo shops. Since the batteries will be sealed, you can turn them on their sides or whichever way they fit best, the same goes for lithium batteries
- Install solar panels to be used as passive energy to back up your battery. While these systems look cheap and affordable to place anywhere, typically on top the car, they are generally more expensive to get the solar panels that produce the energy you want to run things like turn signals and headlights. You will still end up needing an auxiliary battery for these components.
- Connect your ignition to a contactor.
- A contactor will activate the motor when you turn the key. This will act the same way an ignition switch does when on a gas powered car. You will need to rewire the ignition so that it will turn on the contactor. Connect the wires to the car's electrical system and the fuse box to do this. You also need a pedometer which connects to the throttle cable of the gas pedal. This wire in to the controller and gives it signal when its time to accelerate. This is an important special item that may need to be ordered from an electric car conversion website.
- Buy a conversion kit.
- Rather than buying all the parts separately, you can opt to buy a conversion kit. It will have all the necessary components and they will be designed to work together. It will also be put together by a professional. However, the kits available are for select cars and generally aren't universal. You would still need to fabricate a lot of items if the kit isn't made for your car. All in all, it pays to get familiar with welding equipment and a good automotive machine shop.
Things You'll Need
- Donor car with a manual transmission
- Electric motor
- Gel-cell battery
- Engine crane
- Torque wrench
- Controller
- Cables
- Bolts
- Solar panels
- Tires
