Yes. Many have. Take a look at this guy on YouTube:
https://www.youtube.com/watch?v=Ztejn3Y ... EyGCAKRlS1
There are several ways to do it.
- The easiest way is to make an auxiliary battery that has the same voltage as the Leaf's traction battery (96 Li ion in series IIRC). Then connect that to the main bus in parallel anytime the Leaf's battery is connected. A few things that will also help with this setup is
- Make sure the voltages of the auxiliary battery and the main bus are the same before connecting the auxiliary battery.
- Never let the auxiliary battery stay connected to the main bus when the Leaf's traction battery's main contactors are opened.
- With this setup you'll need to have your own way of balancing the auxiliary battery's cells.
- Another option would be to open up the main traction battery and replace or aument the Leaf's cells with more capacity cells. The Leaf's battery isn't very energy dense, and with the right cells replacing the Leaf's cells you could fill up the battery case with 40 to 50kWh of them. Then you could sell the Leaf's cell modules on eBay or use them for something else. The Leaf's battery management system will adapt to the added capacity and give you more range. While doing this you could also add some sort of thermal management system, since the Leaf lacks such a system.
- A third option is to add a second Leaf BMS with it's own battery and have a way to switch between battery systems. However, I understand that the Leaf needs to be paired with any replacement BMS, so this may be difficult.
Personally I'm conteplating doing either number 1 or number 2 to my Leaf, with number 2 as being the best option since I could add more capacity and a thermal management system without a big weight and space penalty. However, my main drawback to doing number 2 is the need to find a very large supply of 18650's for a reasonable price, whereas with number 1 I could technically build an auxiliary battery little by little and still be able to use it as it grows. With number 1 or number 3 that extra battery could even end up being put on a trailer and towed behind the Leaf whenever I need more range. With number 3, that trailer could also be left at a charging station while I drive around town in the Leaf, then come back, get the trailer and keep going.