This is an experiment that I fully expect to NOT work.

These parts let you connect a vacuum cleaner hose from the passenger air vent (on a right-hand drive 24kWh ZE0 2011/2012 Nissan LEAF) to a nozzle that fits into the main battery disconnect panel hole (located between the front and back seats).

The theory is you can set the car to blow cold air out the air vents (AC: off, Mode: top vents only) then close all the other vents and have all that cold air blow over the top of the main battery - in the general vicinity of the cells that reside under the back seat.

Those are the cells that are most densely packed and therefore overheat the most when doing multiple fast charges.

I've used a Dyson Dc08 hose.

To install the blower nozzle you need to remove the battery disconect cover plate. It's held down with 10mm head bolts.

Reasons why this is a bad idea:

1. the cells are located inside a sealed metal can with an air gap between the top of the cells and the top of the can - blowing cold air over the top of the can will translate to very little cooling of the insides of those cells.

2. my current exit nozzle design is a complete guess as to where I should be directing the airflow. (Ideally I'd have a thermal imaging camera looking in the area as it's being fast charged to find any hotspots - if they exist).

3. opening the battery disconnect cover plate will freak some people out. Note: the battery disconnect plug is a fully waterproof and tamper resistant system. When it is removed the battery is disabled - so, no you can't electrocute yourself.

4. To run this setup during a fast charge requires you to (a) turn the car off, (b) plug and start the fast charge, (c) start the car with foot off the brake [ie., not in drive mode], then start up the fans. This means the cooling system is running off only the 12V battery. So you'd better have a good 12V battery that is well charged up - and ideally monitor the voltage so it doesn't run flat as you fast charge the main battery!

Improvements that could be made:

1. Tape the edges of my air vent connector down with wide electrical tape to create a better seal around the vent outlet

2. Wrap the hose in insulation so the cold air is not heated up by the ambient air in the car

3. It would be helpful to know where the cold air is dispersing. Is my nozzle pointing in the right direction? Ideally I'd point a small thermal camera down there to see what's going on. The current configuration is just a guess on my part.

Having said all that - this is a fairly simple, cheap and non-intrusive setup. If it did provide a bit of battery cooling then it might be worthwhile.

My next step is to test it out and use LeafSpy Pro to log the temperature readings of the battery.

I'll test a few strategies:

• - just in my driveway to see if I can lower the temp of the back seat cells from ambient
• - during fast charging (on a long distance drive that requires multiple fast charges)
• - just before fast charging (on a long distance drive)
• - and just after fast charging (on a long distance drive)

I'll update this page once I have any good data to support or undermine the utility of this experiment.

It would be helpful if someone else did the same so we could compare results. Good luck!

This project was inspired by: Nissan LEAF drive battery temperature measures by Terry Young from Cosmo Speed in Japan. His version is designed for the air vent in a 40KWh ZE1 LEAF.

Cheers, Paul

Update 25 March 2021

Added a left-hand drive version of the vent fitting - this one *should* fit in passenger vent (on the right side of the car) of a US/European Leaf.