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Warning Not To Try To Tamper With The Leaf Battery Pack at Home

As a former Nissan Leaf driver of a 2013 Nissan Leaf and as a former owner of an EV Conversion company, I was always tempted to try and extend the range of my Nissan Leaf. I never did it because of lack of time and do to the fact that I leased it so I didn’t want to end up tampering with the car at all. I drove it until it was due back and miss it to this day.

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What the pictures display here is a range extender project gone horribly wrong. This pretty much is a sad state of affairs. This video was found on Youtube and explains the sad process of the experiment.

The video’s editor writes that the battery pack was penetrated to connect a range extender and proceeded to either 1) allow water into the battery box or 2) damaged a BMS wire allowing “overcharging” to take place. There are pictures of the seriously oversized batteries that have expanded due to either the overcharging that potentially took place or because of the fire’s heat expanded the cells (see Nissan LEAF Engulfed in Flame, Details Unknown). The battery pack BMS is also shown pretty damaged and could have caused the meltdown but I doubt it. My feeling here is that water was able to penetrate into the battery cell compartment and was likely the main contributor to the fire.

The lesson learned here is to never allow water to come in contact with Lithium battery cells. While I have seen Nissan Leaf batteries stress tested, I have not seen the cells submerged in water. I don’t recommend that at all.

Nissan Leaf Range Extender Battery Pack Trailer

One thing I would like to see happen, would be for Nissan to create an optional Range Extender Battery pack trailer that would be able to be attached to the Nissan Leaf in order to give it extra range on certain days that it is needed. It would be equipped with a separate EVSE powered onboard charger so that it could be charge at the same location (your garage most likely) and when needed you could just attach it to your Nissan Leaf and then plug it into the rear bumper and offer you go for a longer range trip.

I’ve seen adaptations of this design in many iterations and if you do a google search on Electric Car Range Extender you can find lots of innovative ideas on this subject.

Overall, Electric Car range has been improving and these options will be less and less necessary as EVs come stock with longer range battery packs. The main idea here has many good reasons for it.

  1. Stock EV battery packs could stay at 100 miles of range but offer a 100 or 200-mile range rental option for those days or trips that require longer Leaf Range.
  2. The cost of the EV could be less because you wouldn’t need to pay for battery capacity that you may never need but once or twice a year.
  3. The car would be lighter the majority of the time so that would help increase the range of the car except when towing the range extender trailer.

In general, the range extender trailer idea is not new but if properly engineered for safety. I’d love to see a rental market opened up like this so that I wouldn’t have to buy an overpriced battery pack that I would only rarely need.

The other option is to just get a BMW I3 with a Range Extender but I just can’t deal with the design styling of that car. I applaud BMW for making the car, it just a personal choice about the styling.

There is a hybrid pickup truck coming soon with 80 miles of EV range and then a gas range extender for those longer trips. I’ll write more about that in another article.

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Dudamus (not verified)    April 28, 2017 - 11:49AM

It looks like the main battery pack overheated and swelled but did not catch fire. Probably the 18650s in the trunk bursted into flames.

Dudamus (not verified)    April 28, 2017 - 11:52AM

The LEAF is what it is, a great around town car. Maybe some professionals will come up with some aftermarket add ons.

Dudamus (not verified)    April 28, 2017 - 11:58AM

I just double checked. It seems Lithium Metal batteries are susceptible to fires in water, but lithium ion batteries are made specifically to be water resistant. When a lithium ion battery catches fire water is one of the recommended mediums to extinguish it. There may be numerous types of lithium ion batteries however, but I think the whole point of making them an ion battery instead of metal was to avoid the water problem. consequently lithium ion batteries have a lot less power than lithium metal. Hopefully battery technology will continue to advance.

TylerF (not verified)    April 28, 2017 - 8:26PM

The moral of this story is don't mess with stuff you don't understand. It should be clearly pointed out that under normal circumstances the Nissan Leaf battery is absolutely safe. I have unexpectedly drove into high water multiple times with never an issue. I also run through a car wash, including undercarriage jetst about once a month. The car is designed to be used like any other car.

Towing a battery pack makes no sense. First, the additional weight and drag would prevent getting the standard range and additional charge would also be used quickly. Just make sure you have a fast charging port and Second, it's cheaper and easier to just rent a car for longer trips with the money saved driving electric. A long trip in an ICE always makes me appreciate my Leaf more.