Add 40 miles driving range to Nissan Leaf with Enginer's add-on battery pack
In the gasoline cars market there is a large industry supplying add-on parts and accessories for a wide range of purposes. In the due course of time there will surely be an accessories market for electric or hybrid cars. Enginer is one such company, being most famous for the plug-in Prius conversion kit that's been on the market for several years. The company recently announced, on the My Nissan Leaf forum, a range of add-on battery packs for the Nissan Leaf to extend the Leaf's driving range by as much as 40 miles.
Getting a long driving range with an electric car is simply a matter of carrying enough energy storage capacity. The huge range of the Tesla Model S (EPA certified at 265 miles) is due simply to the 85 kilowatt-hours of energy storage, compared to the 73 mile driving range of the Nissan Leaf due to its 24 kilowatt-hour battery pack. When you buy an electric car you're stuck with the design considerations of the company which built the car. But what if you could add modifications to the car? Gasoline car owners do this all the time, why not electric car owners?
What Enginer has done is develop a method of tapping into the Leaf's high voltage power system, to add additional battery capacity. Kit installation does not cut any wires, and the car can be returned to stock state at any time. The company claims it does not void the Leaf's warranty.
The kit consists of a large box containing a 48 volt lithium-iron-phosphate battery pack, and a DC-DC converter to step the voltage up to what's necessary for the Nissan Leaf. The box does take up room in the trunk area. The 4 kilowatt-hour model weighs 160 lbs, extends the driving range by 20 miles, and costs $3,495. The 8 kilowatt-hour model weighs 260 lbs, extends the driving range by 40 miles, and costs $5,495. The 12 kilowatt-hour model weighs 360 lbs, and costs $7,495. Enginer's battery pack is rated for 2,000 charge cycles. We should note that the miles of driving range Enginer quotes is similar to the "100 miles of driving range" that Nissan claims, when in fact the EPA certified range of the Leaf is 73 miles. That is to say we should expect the actual range extension to be less than the figure Enginer quotes, and the actual range extension will depend on driving habits.
Charging the battery pack is done via the J1772 port on the Leaf. This battery pack does not get charged if the Leaf is charged via the CHADEMO DC quick charge port.
Installation is not terribly hard, but should be done by someone competent with tools and electrical wiring. The Enginer range extender kit taps into the DC High Voltage wires, the AC wires for the charging system, some EV controller signal wires, and the charger DC relays. The website has a series of pictures outlining the steps with which you can gauge whether or not you are up to this task.