HOT Weather Charging Strategy to Reduce Battery Stress

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

gmcjetpilot

Well-known member
Joined
Oct 30, 2017
Messages
130
Mid June and SUMMER is here in the Mid South with temps in the 90's, heat index over 100F.

My 2015 LEAF SV just went to 10 bars at beginning of year, when it was cool, about 37,000 miles. I am trying to make the battery last at least another 5 years. We all know HEAT is a killer. Unfortunately I am parking on the driveway lately because I had to store stuff in it Temporarily. The garage (not air conditioned) is fully insulated and drywalled. The garage door is insulated.. It is definitely cooler than the drive in direct sunlight. (note to self clean out garage this weekend)

My Strategy to not Heat Stress the Battery
1) Keep charge between 30% AND 80% MAX (50 mile range, good for errands)
2) Charge only 1 to 1.5 hours at a time (typically about 40%-50% added I recall with my home 4.6Kw level-2 charger)
3) Set timer for 5 AM when temps are the lowest, currently mid 70's.

I think all of these will help a little. What do you think?
 
gmcjetpilot said:
3) Set timer for 5 AM when temps are the lowest, currently mid 70's.

I think all of these will help a little. What do you think?

If you can hold off on charging until the latest possible time before sunrise, that should give plenty of time for the battery to stabilize with the ambient air temperature at night that will benefit during the day since it will take a while to warm up in the air also. That would probably have the greatest benefit, but it is a car and if you need some extra range during the day, then try to be nice to the battery but don't baby it if you need the car to be a car. :)
 
Set up a high volume adjustable fan so that it will blow cool air under the car (rear is better but front will also work) from about 2:00am until you unplug the car.
 
gmcjetpilot said:
heat index over 100F.
IIRC that index matters to humans affected by humidity. LEAFs do not have evaporative cooling.

I'm a fan of parking outside for better ventilation. I park in the shade or on dirt/plant matter. Concrete in the sun is bad, and black tarmac is nasty. You could try spraying water on a hot surface to cool it down.

Otherwise your list looks pretty good.
 
LeftieBiker said:
Set up a high volume adjustable fan so that it will blow cool air under the car (rear is better but front will also work) from about 2:00am until you unplug the car.
Aren't there air intakes near the front that direct air around the battery? if so placing the fan in the front near those intakes would probably be better as the air would be passed around the actual battery itself vs just under the vehicle?
Crazy enough the eNV-200(not available in N. America) did(does?) use fan cooling when charging the batteries, too bad that feature never made it to our very similar Leafs :(
 
LeftieBiker said:
Set up a high volume adjustable fan so that it will blow cool air under the car (rear is better but front will also work) from about 2:00am until you unplug the car.
Been there, done that (10 years ago)...didn't work.
Unfortunately, nothing he does will keep him from dropping (probably) >2 bars in the next 5 years for a lizard battery.
Been there and done that also (check my sig).
Having said all that, his item #1 is a good idea in general for EVs
 
If experimenting with fans and all, I strongly taking notes on ambient temp and battery temps. One may find it does little or no good, or the opposite.

When I still had Leaf, I found that if I parked the car outside where it was cooler at night time than inside the garage, it took MANY hours for the battery temp to drop and it really only dropped much if it was much cooler outside. Battery has lots of thermal mass.

Example: 75 F in garage vs. 65 F outside - you may not see a big temp drop after a night outside. But, if 75 F in garage and 50 F outside, after many hours, yes, the temp drop should be more significant.
 
If experimenting with fans and all, I strongly taking notes on ambient temp and battery temps. One may find it does little or no good, or the opposite.

When I still had Leaf, I found that if I parked the car outside where it was cooler at night time than inside the garage, it took MANY hours for the battery temp to drop and it really only dropped much if it was much cooler outside. Battery has lots of thermal mass.

Yes, it really does depend on the temperature difference. My experience is also that it needs to be at least 10F cooler overnight to get significant cooling.
 
cwerdna said:
Example: 75 F in garage vs. 65 F outside - you may not see a big temp drop after a night outside. But, if 75 F in garage and 50 F outside, after many hours, yes, the temp drop should be more significant.

You cooked your battery with DC charging to save a few pennies, and you paid for it with more degradation. Outside ventilation was not enough to mitigate your behavior. Don't blame Newton's law of heating/cooling. It works as advertised.
 
SageBrush said:
cwerdna said:
Example: 75 F in garage vs. 65 F outside - you may not see a big temp drop after a night outside. But, if 75 F in garage and 50 F outside, after many hours, yes, the temp drop should be more significant.

You cooked your battery with DC charging to save a few pennies, and you paid for it with more degradation. Outside ventilation was not enough to mitigate your behavior. Don't blame Newton's law of heating/cooling. It works as advertised.
Who me? My 2nd Leaf that I recently sold and had from July 2015 until about a week ago doesn't even have a CHAdeMO inlet.

The only time I ever had a CHAdeMO-equipped Leaf was when I leased my 1st one for 2 years.

For the record, it isn't a few pennies either on Pacific Gouge & Extort. https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_SCHEDS_E-1.pdf page 1 are our prices. Charging an EV at home would push me into tier 2 since tier 1 is about 300 to 327 kWh for a 30 day billing month. (Allotments per blling day are on page 3. I'm in territory X, code B.) So, the marginal cost to charge at home is about 32.6 cents per kWh (actually 1 cent more than that since I pay my city for supposedly 100% renewable energy).

There is a dual-standard DC FC 5 miles from home that is 19 cents per kWh but my former Leaf can't use it anyway. It was also broken for over 3.5 months at one point. I was getting free or heavily discounted (75% off EVgo prices) DC FC juice on my Bolt thanks to DrivetheARC (now over). The above DC FC location also has a couple 19 cent per kWh L2 J1772 handles. They used to be free.

The temps I'm talking about and experiments I did w/that Leaf were with no charging at home. Was just moving it or leaving it outside when it got hot/warm in the garage and was cooler outside. I almost never charge my EVs at home due to PG&E and prior to COVID, having free L2 juice at work.

Today, I'm actually at the office for a full day of work for the first time since mid-March 2020. Was going to be too hot at home. Forecasted highs for my city for today thru Friday are ~95 to 101 F or so.
 
Back
Top