Is 16 Amps Sufficient to Enable Battery Cooling When Parked?

[MachEMaster]

The easiest way is to get another set of clamps and use dedicated circuit monitoring. They would just plug into the middle ports of the sense monitor and then you would toss them around the circuit that goes to the EVSE.

It's very hard for Sense to determine EVs that aren't "as popular" because it's all AI driven. The MME has an electrical signature that can be evaluated but there needs to be a lot of those for them to have a good solid foundation to train the AI models. The more people who have Sense that own MMEs the more data they have.

Like I said however, the easiest and most bulletproof way is to get the extra clamps. There's no other way to tell it that it's your EVSE.

Ok thanks! That should not be a problem. I have my EV running off a DCC load shed device on a 50 amp circuit. This accounts for my puny 125Amp service.

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[DonRon64]

Another option to dynamically control the panel load's if that is the concern or desired is the line of Emporia energy monitoring and EVSEs. Their smart home products are integrated to allow monitoring and automatically controlling the peak loads on your electrical service.

I have this setup at one of my residencies to leverage those advanced features if needed when/if my Mach-e arrives. Check them out.

https://www.emporiaenergy.com/

 

[Ming]

My guess is that if it is 120V then the answer is no. When you use 120V then it does not even charge the 12v battery while plugged in, which mean it doesn't get enough juice from the wall outlet.

If it is 240v then probably yes.

I would be very surprised if 120V 16A is not enough to cool. My window AC, plugged into a 15A circuit (probably drawing 12A), keeps a large room cold. Rated 10200 BTU.

 

[fmtexmme]

Because there’s a rumor going around that if you keep the battery below 90 degrees, you’ll get an extra 2% of life out of it. Or that an hour spent at an ambient temperature of 101 degrees will shorten the life of the battery by 2 years.

The general thought that high heat is bad for a battery is true, but rumor of one hour at 101 will shorten the life by 2 years is, well, BS. We've had a good heat wave here is Texas with 11 straight days over 100 degrees, many of them reaching 102-105. That would mean if you drive your car to work, you're going to be subjecting the battery to 3-4 hours of temps over 101 in a day. If the rumor were true, in one day you would have shortened your battery life by up to 8 years. and completely trashed the battery in one week since I'm pretty sure these batteries don't have a 30-40 year life expectancy.

 

[MailGuy]

Because there’s a rumor going around … Or that an hour spent at an ambient temperature of 101 degrees will shorten the life of the battery by 2 years.

If that were true there would be a lot of Mach E owners walking around the Sonoran desert right now. My battery would lose 16 years of life today alone. YMMV

 

[dmastro]

I don't think the battery temperature concerns are being interpreted correctly. I don't think sitting in an ambient temperature of 100F is going to cause a massive impairment over time. The constant cycling of cooling and heating to maintain the battery temperature would seem to be the reason for any diminished life.

 

[devmach-e]

If that were true there would be a lot of Mach E owners walking around the Sonoran desert right now. My battery would lose 16 years of life today alone. YMMV

I was being most facetious with my comment. Or rather, excessively sarcastic.

I do think that heat is something to be concerned with with the batteries. But I think people take the concern to levels that are beyond reasonable. Presumably Ford and other manufacturers have picked a battery design (chemistry, ability to heat/cool pack, etc) that doesn't require micromanaging things. The manufacturers are on the hook for replacements in the first 100K miles, it is in their own best interest to have a battery pack that can withstand owners having to leave a car un-plugged at the airport for 10 days in extremely hot or cold weather. Or someone going on a road-trip and having to run it down to 10% and charge up to 100% multiple times (we'll ignore the contactor welding issue here).

 

[devmach-e]

The general thought that high heat is bad for a battery is true, but rumor of one hour at 101 will shorten the life by 2 years is, well, BS. We've had a good heat here is Texas with 11 straight days over 100 degrees, many of them reaching 102-105. That would mean if you drive your car to work, you're going to be subjecting the battery to 3-4 hours of temps over 101 in a day. If the rumor were true, in one day you would have shortened your battery life by up to 8 years. and completely trashed the battery in one week since I'm pretty sure these batteries don't have a 30-40 year life expectancy.

As I said in my other reply, I was being facetious/sarcastic with the specific example of the car sitting in 101 heat with a 100% charge resulting in 2 years less life. But that seems to be the nightmare scenario everyone envisions when the question of keeping the battery happy comes up.

 

[fmtexmme]

As I said in my other reply, I was being facetious/sarcastic with the specific example of the car sitting in 101 heat with a 100% charge resulting in 2 years less life. But that seems to be the nightmare scenario everyone envisions when the question of keeping the battery happy comes up.

My apologies. I missed your reply. People do make up the craziest things about batteries in an attempt to discredit EVs. I saw on another forum where someone claimed in Europe they were scrapping EVs after two years because the batteries were going bad. I called him out, pointing out EVs that new would still have their battery under warranty so the manufacturer would replace the battery. Of course, he never responded to that.

 

[Flyboy]

So, I can answer your question, but I'm not sure battery cooling in an issue since they are under the car and will be the coolest thing on your car (unless you are charging or discharging).
I have seen the vents open and the fan run during the charge cycle on hot days. I dropped the charge rate from 16 to 6 amps and the vents stayed closed and fan didn't come on.

My Open EVSE (https://store.openevse.com/collections/all-products) charger is always set at 16 amps. Set here, it will charge at 4.3% per Hour which is plenty quick enough for most of my days. The car is only charged when the SOC drops below 65% and I only charge to 80%.

BTW - if you plug in the travel charger that came with the MME to a 15 amp 120 V outlet, you can get about 1% per hour charge rate (Ext Range).

Having been involved with Li Metal-hydride battery development (back in the 80's), I can tell you that cycling a battery from 100 to 0% and back is the best way to kill it quickly. Also, the faster the charge rate, the hotter the battery gets, the quicker you kill the battery.

The maximum draw for a morning "Warm-up" of both the batteries and the cabin is 16 amps, that's the magic number.
I have also measured the draw for the AC unit to cool a hot cabin and that is much less that heating, initial draw of 9 amps dropping quickly to 6 amps and then 4 amps - I'm sure this is dependent of the interior temperature.

 

[Blue highway]

For those so inclined - here is an academic article on how much temperature matters.

TLDR -
it matters a lot more than those who say temperature doesn't matter
it matters a lot less than those who say their batteries are degraded after a few days at 100+

https://www.nature.com/articles/srep12967#:~:text=The degradation rate of the,from 4.22% to 13.24%.

 

[luckie]

My Bolt EV would cool/heat the battery pack regardless of whether it was plugged in or not. It did have different thresholds when it was plugged in Versus when it wasn’t. I am surprised that the MME only runs battery conditioning when plugged in, but Ford may have chosen to prioritize range over that of battery temperature. Perhaps they found that there was minimal loss of capacity, or that a battery sitting at a high ambient air temperature didn’t raise the battery’s internal temperature into a dangerous zone.

I agree. It does seem surprising for the Mach-E to not be able to cool an overly hot battery unless it is plugged into grid power (under any/all circumstances). The Bolt EV does a little cooling if needed using power from the HV battery when sufficiently charged, and cool more so if plugged into grid power. Of course we do not know if this assertion about the Mach-E is TRUE yet. It's just rumor until strong evidence is provided. Mach-E may behave just like the Bolt EV does, don't think we have evidence otherwise as yet. Lol.

 

[ShadowCVL]

Holy jeebus, if you are that worried about the power draw of the car for cooling you really should have an electrician come out.

200 amps for a house under 4K square feet should be more than enough to charge a car, run an ac, run the stove/oven, and dryer all at the same time.

go check the side of yourheat pump/ac for the max amperage, I bet it’s under 25. Your car will not Pull that much just for cooling, mine pulls about 20 when I remote start it then it settles down to about 15. (At 240).

I have a large house with 2 AC units, many computers (including some that were crypto mining last summer, and no my cards weren’t used just for mining happy byproduct) electric dryer, oven, and rang, with everything going full blast at 7pm on a weekday it never topped 140.

the chances are extremely low that you could be getting even close with the car, ac, and a tv (by the way any tv made in the last 5 years will pull less than 3 amps at 120)

 

[devmach-e]

I agree. It does seem surprising for the Mach-E to not be able to cool an overly hot battery unless it is plugged into grid power (under any/all circumstances). The Bolt EV does a little cooling if needed using power from the HV battery when sufficiently charged, and cool more so if plugged into grid power. Of course we do not know if this assertion about the Mach-E is TRUE yet. It's just rumor until strong evidence is provided. Mach-E may behave just like the Bolt EV does, don't think we have evidence otherwise as yet. Lol.

The.Bolt was kind enough to tell us that it actually used power for conditioning the battery while unplugged. It was there plain as day in the Energy Detail screen. I wish the MME would tell us how many kWh it used from the battery rather than forcing us to do the calculation. I also wish we had a power meter like the Bolt had.

 

[devmach-e]

Holy jeebus, if you are that worried about the power draw of the car for cooling you really should have an electrician come out.

200 amps for a house under 4K square feet should be more than enough to charge a car, run an ac, run the stove/oven, and dryer all at the same time.

go check the side of yourheat pump/ac for the max amperage, I bet it’s under 25. Your car will not Pull that much just for cooling, mine pulls about 20 when I remote start it then it settles down to about 15. (At 240).

I have a large house with 2 AC units, many computers (including some that were crypto mining last summer, and no my cards weren’t used just for mining happy byproduct) electric dryer, oven, and rang, with everything going full blast at 7pm on a weekday it never topped 140.

the chances are extremely low that you could be getting even close with the car, ac, and a tv (by the way any tv made in the last 5 years will pull less than 3 amps at 120)

According to my UPS, when the 65” Samsung TV is on, and the surround sound is going through the stereo receiver/Amp, I’m only pulling 1.5A.

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