Very Slow Charging

[tallgirl]

I'm borrowing an SV for the weekend before wrapping up wrangling on an SL.

In the interest of seeing how long it would take to recharge one from fairly empty (it was low on e-fuel and I had to hook up the e-hose to e-fill it ) and how hot it would get, I plugged it in to a 120 volt outlet and let it charge.

Forever.

But then I grabbed an infrared thermometer and measured every surface I could find (and the area around the car) and there was very little additional heat. I couldn't find anything more than 2*F above the surrounding area. Not the slab, the ceiling, the underside of the car, nothing. My Vectrix (E-bike) used to heat the entire area around the garage, which explains why Vectrix battery packs all seemed to die from overheating.

Do people in hot climates just let their Leafs charge forever overnight on the 120 volt e-hose as a way of preventing high temperatures?

My dealer got a really good deal on the e-fillup and the sun barely shined, so I got a lousy deal on the electricity. But I think I learned something really important -- the little buggers =can= be recharged on a 120 volt outlet and they don't seem to get hot.

 

[DaveEV]

They don't get hot charging on L2, either. The onboard charger is very efficient and the charge rate is slow enough that the battery won't see any significant heating, either.

 

[LEAFfan]

They don't get hot charging on L2, either. The onboard charger is very efficient and the charge rate is slow enough that the battery won't see any significant heating, either.

+1 I've rarely used 120, but have already benefited with the much faster L2 ( 3.3 vs. 6.0).

 

[Nubo]

You won't find heat boiling off the car in either case. The one difference I note between L1 and L2 is with L2 I can feel some moderate warmth in the coolant hoses -- heat from the onboard charger. With L1 it's hard to tell the hose temperature from ambient.

As far as the battery pack, my understanding is that most of the heat generated is in the very end of the charge profile, and the car slows down the charge near the end anyway, so not sure L1 vs. L2 has much of a material difference there.

The advantage of L2 in hot climate is that there is time to delay charging until the cool of night, which may give the pack a chance to cool off from a hot summer's day before charging begins.

 

[JeremyW]

Yup. 120V or L1 is very slooow. I always tell people while you can charge on a regular outlet you don't really want to.

Then again I have visited a friends house in the mountains where L1 was just fine because my car was just sitting for a day and a half. There are a few on the forum that use L1 exclusively because they have such a short commute. It also makes sense for long term parking at airports and the like.

An outlet will give you about 3-5 miles of charge per hour, 3.8 kW L2 will give you about 12-15 mph, and 6.0 about 20-25 (newer leafs are significantly more efficient while charging, especially at the faster rate).

 

[tallgirl]

Thanks for the feedback. I didn't have a choice -- we're still trying to close the financing (I started a company 4 years ago and have lousy credit as a result -- not all small business owners get rich!) and the car was on loan.

I'll likely have to resort to using a NEMA 5-15 ("standard" 120 volt receptacle) for a while until I can get a service upgrade done. Most likely I'll get the "EV Upgrade" charger first chance I get so it doesn't take forever.

I have about 5kW of solar panels at the moment and am effectively at the limit of the service panel. I expect to upgrade to something closer to 10kW PV and will need a 200 amp service whenever that happens.

If anyone is here in Austin, I'd love to bring some gear to your house and instrument the underside of your car while it cars on L2.