Lower Amp charging healthier for battery?

[luebri]

The owner of the company doing my solar, is also Tesla certified Powerall and Charger installer. He installed my Ford Charge Station Pro today, but he recommended not charging at the full 80A unless totally necessary. I assume this was for the health of the battery? When I told him that Ford does not provide the ability to change the Charge amperage via software (like Tesla) he was pretty surprised.

My question... is there truth that charging at a lower amperage is better for the long term health of the battery? Or is there any other reason to charge at a lower amperage setting?

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[Jif1025]

You can change the charge rate with software. I have mine run with 80amp service but derated via the app to 48amps. Just fyi

 

[luebri]

Well look at that!

You can change the charge rate with software. I have mine run with 80amp service but derated via the app to 48amps. Just fyi

Well look at that! Sure enough. Why did you derate?

 

[Jif1025]

Honestly, because most nights I can charge overnight and can hit 90% well before I depart the next morning even at 48amps. I do like the convenience of knowing if I need to charge extra quickly or want to go to 100% SoC, I can easily boost the rate- but I don’t see that happening often at all.

 

[bmwhitetx]

You can change the charge rate with software. I have mine run with 80amp service but derated via the app to 48amps. Just fyi

If you have only an 80A breaker (I assume that's what you meant when you said service), then you should also set the hardware limit switch on the charger. Under the cover is a dial where you select the max rate regardless of software. The instruction manual provides detail. You would set the switch to the 64A setting (80% of 80A). Code requires that EVSE's limit their charge rate to 80% of the breaker. You can still derate further to 48 in software.

If you installed a 100 A breaker then you are good with the hardware 80A charge setting.

 

[Jif1025]

Apologies if I worded it poorly- it’s a 100amp breaker but I have the box set to 80amp, then de rated to 48amps

 

[chillaban]

For the car, I don’t expect 80A charging to be any worse for it than 48A, it’s so minuscule compared to how much even gently accelerating or maintaining your speed uses.

But in my experience with 2 residential and a dozen at work chargers, the higher the amperage they charge at, the more prone they are to something going wrong. Usually in the form of spurious GFCI faults interrupting the charge at night. I’ve also seen 50/100A breakers buzz when they approach their 40/80A limits.

Yeah you can keep having your electrician come back to diagnose and fix all of these things but it’s often easier to just charge at a slightly slower rate.

 

[Jim Lewis]

Tom Moloughney, on his State of Charge YouTube channel, has an interview with Darren Palmer, VP of the electric vehicles division at Ford. Palmer says that Ford didn't want to end up paying for replacement batteries under warranty. Their warranty of 8 years or 100K miles, whichever comes first, while still having at least 70% SOC capacity left in the battery, is designed to be met if the user charges EVERY DAY to 100% with a level 2 charger. IIRC, Palmer says in the interview if you stay within the 20% to 80% SOC, you'll do far, far better than that. So, reducing the rate of charge to something less than 80 amps with the FCSP will just be more icing on the cake if you charge almost entirely at home.

(warranty segment starts at about 28:18 into the video)

What I would like to know about charging at home is what manual options do you have to set battery temperature control while parked and plugged in. And when it's 110 deg F outside my garage and maybe 90 to 95 deg inside my garage at the peak of summer heat, if automated battery cooling kicks in, how much is effectively running an AC compressor (the one on my truck) going to further roast the truck in my garage?! Our HOA has strict rules about NO window air conditioners. Still, they seem to be lax about installing mini splits, so that might be one expensive possibility to keep the truck battery comfy in the garage while still helping to pillage the environment despite the would-be "greenness" of the truck. We have a bad roof design and too many trees all over for solar panels. One of our neighbors actually trimmed the Heck out of his live oaks to install a ton of solar panels at ground level in his backyard!

 

[Capertrj]

Just curious. In relation to power savings. I think people have said roughly there is ~15% in charging losses with the inverters. Are there more or less charging losses with a higher/lower rate of charge( level 2 at home).

Example: let’s say at 48A charging losses are 13% vs 18% for 80A. If there are less loses charging slower then there could be some cost savings with electricity.

It very well might be equal at all levels but something I just thought of.

 

[Theo1000]

I charge at 32 amp. I find the wiring in the outlet stays a lot tighter long term at 32 amp. Just did my annual tightening of all my EVSE connections. The 40 amp outlets needed at least 3/4 turn tightening for both hot leads. The 32 amp lest than 1/8 turn. This is just annual inspection mind you.

I drive a lot. Have just over 28,000 miles on my truck in -9 months. IME very very few people who charge at home overnight need more than 32 amps.

 

[Pod]

So my charging via the 110 outlet in my garage should be amazing. ( actually doing this, my commute is short )

 

[256fail]

This is a timely thread. I've been researching what the best amperage is to charge. I currently have a 48amp/40amp through my 14-50. I've been setting it for 32amps. My brother has owned his Tesla for a year and charges I think around 24 amps. I can easily charge at 24 amps and make just start doing that.

Slightly off topic. I have a seperate 3rd garage where I park half the time, but my level 2 charger isn't in there (it is in the main garage). During the winter, would I gain anything, by at least plugging in my mobile charger 110v on the truck? Would it at least help precondition? I don't need it to add range on those nights when I park in there. Just trying to find out if there is any benefit or should I not worry about it being unplugged overnight?

 

[luebri]

Slightly off topic. I have a seperate 3rd garage where I park half the time, but my level 2 charger isn't in there (it is in the main garage). During the winter, would I gain anything, by at least plugging in my mobile charger 110v on the truck? Would it at least help precondition? I don't need it to add range on those nights when I park in there. Just trying to find out if there is any benefit or should I not worry about it being unplugged overnight?

Read thru my charging log reports in this thread…

https://www.f150lightningforum.com/forum/threads/ideal-charging-practices.14066/post-296491

…it’s fairly detailed. Bottom line is, yes, even 110v charging provides a noticeable thermal benefit to the battery when sitting in colder temps overnight. As a result your morning drive would be more efficient as your battery would be closer to ideal operating temperature.

 

[luebri]

Just curious. In relation to power savings. I think people have said roughly there is ~15% in charging losses with the inverters. Are there more or less charging losses with a higher/lower rate of charge( level 2 at home).

Example: let’s say at 48A charging losses are 13% vs 18% for 80A. If there are less loses charging slower then there could be some cost savings with electricity.

It very well might be equal at all levels but something I just thought of.

Great question! Ive been wondering this myself. I can monitor whole home usage via my solar but not specifically monitor usage of my FCSP because the data graphs in FordPass are hot garbage.

I've done a lot of playing with charging at different charging temps as mentioned in the previously mentioned "ideal charging practices" thread and my hypothesis from the rough data is that, atleast in cold temps, there is actually less loss at a higher charge rate.

If someone has some data on this question that would be great. If not, I would love for someone with an Empria Vue or an adjustable EV charger that shows detailed data logs to compare the losses at the various charging Amp settings.

 

[Maquis]

Since conversion losses are roughly a constant percentage, it shouldn’t matter because of the time factor. EG..15% of 10kw for an hour is the same as 15% of 5KW for 2 hours. In both case, you’ve added the same amount of charge and lost the same amount of energy.

However, there are fixed (fixed in relation to charge rate) overheads to consider, such as the truck’s charge monitoring and battery heating or cooling as necessary. The energy used by these will be proportional to time regardless of charge rate. This should make higher rates more efficient.

As an extreme example of this, consider that level 1 charging incurs about a 30% loss.

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