Faster AC charging

[wolf123]

Hi

I've just received my Tesla Model 3 SR+ this week and been watching plenty of videos on YouTube including
Bjørn Nyland's channel. He discusses the fact that fast DC charging degrades the battery quick.

Currently I have access to a 7kW charger and a 22KW charger (AC). Is it kinder to the battery to use the slow charger or is degradation less of an issue for AC charging/lower speeds?

Thanks

 

[wolf123]

Sorry should have said 12KW not 22KW - don't seem to be able to edit

 

[Adopado]

Sorry should have said 12KW not 22KW - don't seem to be able to edit

doesn't matter ... the M3 charges at a max of 11kW on AC

 

[CMc1]

Wouldn’t worry too much about fast DC too. Guy here was first to go over 100k mi in a model 3, predominantly DC fast charging, and had only around 2.5% loss in range.
Tesla owner becomes first to push Model 3 to 100,000 miles, here's how it's doing - Electrek

I’m at over 22,000 on my M3 since August, supercharge at least 4 times a week and I’m seeing very little degradation.

just enjoy the car

 

[gangzoom]

Wouldn’t worry too much about fast DC too. Guy here was first to go over 100k mi in a model 3, predominantly DC fast charging, and had only around 2.5% loss in range.
Tesla owner becomes first to push Model 3 to 100,000 miles, here's how it's doing - Electrek

Electrek also have historical articles on how amazing the original Tesla 85 packs are at not degrading and rapid charging, we all now the opposite true.

If you plan on keeping any EV longterm avoid DC rapid charging, its a guaranteed way to kill your battery.

The latest real world data shows DC rapid charging causes a measurable increase in degredation even at below 50k miles, 6% for DC rapid charged car versus 4% for less DC charged car at 50k kms.

If you lease your car it doesn't matter as the worse degredation will effect the next owner and not you, but either way the battery will be hurting from been regularly DC rapid charged.

 

[Durzel]

So.. supercharging the car degrades the battery?

Is charging the only thing that degrades the battery? Wouldn't it also matter what level you are charging it to each time, and how many deep discharges it's done etc?

 

[Jason71]

When it comes to the battery all charging is ultimately DC charging its just a question of whether the AC/DC conversion is done in the charger or by the car. As such 7kw/h or 11kw/h are both tiny compared to the 120-250kw/h max that you can get from the various generations of supercharger or even the 50KW you get from most 3rd parties. I'm going to stay out of the argument as to whether Rapid charging has an impact on battery health but you certainly shouldn't stress about 7kw/h vs 11kw/h

 

[Jason71]

So.. supercharging the car degrades the battery?

Is charging the only thing that degrades the battery? Wouldn't it also matter what level you are charging it to each time, and how many deep discharges it's done etc?

yes. From what I know about Li batteries I am going to say I think repeated charging to 100% ( and holding there for any period) thendraining to near zero almost certainly does far more damage than rapid charging. the fact that Tesla tells you not to do those things if possible but is OK with rapid charging supports that point

 

[gangzoom]

I'm going to stay out of the argument as to whether Rapid charging has an impact on battery health but you certainly shouldn't stress about 7kw/h vs 11kw/h

There is no arguement about rapid charging been bad for batteries, its why Tesla limit the rapid charge on all their cars once you hit a certain amount of rapid charging - Model 3 included and I would be amazed if the Y isn't also.

But charging at 11KW or 22KW seems unlikely to do any harm versus 7KW.

 

[davidmc]

So.. supercharging the car degrades the battery?

Is charging the only thing that degrades the battery? Wouldn't it also matter what level you are charging it to each time, and how many deep discharges it's done etc?

All charging degrades the battery (Fast or slow) but the faster a charge, the faster battery degradation occurs. Also the amount of charge cycles a battery does degrades the battery. Type of usage of a battery also degrades it. Like if you were using your car mainly at a race track where high speeds/acceleration are involved, this would degrade the battery a lot quicker. Hotter/Colder Climates can also degard batteries quicker. Basically, using or even storing a battery degrades over time from the nano to the macroscopic scale.

I belive the newer 21700 batteries (in the M3) are better at the DC charging than the older 18650's. Also newer chemistry in the battery makes the batteries last longer and cope with higher charge rates.

Roll on the 1 million mile battery

Nice little read if you fancy it :S

https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

 

[Adopado]

So.. supercharging the car degrades the battery?

Is charging the only thing that degrades the battery? Wouldn't it also matter what level you are charging it to each time, and how many deep discharges it's done etc?

Yes, you are surely right on that. Everything in moderation!

Batteries are made to be charged and discharged. It's a bit like your own life span ... doing stuff in your life wears you out and at a certain age you become considerably less capable ... but you make life compromises in how you live that makes the best of the life you choose. Most people are not going to decide to avoid ever having a drink, or catching some sunshine, even though these things are likely to have an impact on your life span ... same with Supercharging ... it's part of EV life!

 

[Rustybkts]

@wolf123 I have been building EV's since 2008 and like yourself have an SR+.
The less stress on lithium batteries the better they will last. For general use I limit mine to around 75% charge which is easy to do in the M3 as you simply drag to the max charge. Recharge when the level drops below 25%.
Only go for the full 100% charge when you need it on a run. I am sure that most owners will not see any appreciable drop in range and to be honest its not too different from the loss in range of a high mileage ICE.

 

[Jason71]

@wolf123 to be honest its not too different from the loss in range of a high mileage ICE.

If we are being really honest it kind of is very very different since most ICE cars have a lot more range to begin with and much more readily available and faster network of "recharging" stations. I don't want to subvert this thread but If your ICE journey is out of your range no one is ever concerned or has to plan ahead of time where they will fill it up, how long it will take, whether there will be space at the filling station when they get there, whether the filling station will be out of order or if they have the right app/card to even use it in the first place. all of these are legitimate concerns for all EV owners. I am 100% comfortable with those issues but you can't pretend they don't exist.

 

[Mr Miserable]

Yes, you are surely right on that. Everything in moderation!

Batteries are made to be charged and discharged. It's a bit like your own life span ... doing stuff in your life wears you out and at a certain age you become considerably less capable ... but you make life compromises in how you live that makes the best of the life you choose. Most people are not going to decide to avoid ever having a drink, or catching some sunshine, even though these things are likely to have an impact on your life span ... same with Supercharging ... it's part of EV life!

I was told as a youngster that I was discharging too frequently.