[promee]

In this video, he said BMW already reserved some portions of capacity and no need to keep 80%.
He said bmw recommend always go 100%.

Which one should we listen to?


Edited again
Summarized his video FYR:

1. Go 80% on other brands.
2. Always go 100% on BMW.
3. Fast charging to 80% only, because it's most efficient.

[RichardInCA]

I had wondered the same thing, but consensus when we posted this elsewhere was that 80% is still a safe target if you are keeping the car for a while. If you need the extra range, then go for it, but I think overall it’s moving away from the mindset of looking at batteries as being an electric equivalent to a tank of fuel that we routinely top to 100%.

It doesn’t mean you’re going to kill your battery if you charge to 100% some of the time, but DC fast charging to 100% as the only way of charging is probably going to erode battery capacity over the mid term.

[andykitty]

I’m not sure where he gets the idea that BMW recommended charging to 100%. Both the manual and MyBMW app suggest charging to only 80% is recommended for optimal battery life.

[promee]

Summarized his video FYR:

1. Go 80% on other brands.
2. Always go 100% on BMW.
3. Fast charging to 80% only, because it's most efficient.


I'm a little bit convinced.

[andykitty]

Well, between a YouTuber/SA and the user’s manual, I believe what the manual says.

[SpaceSilver.X1]

if BMW did engineer the battery with extra capacity, perhaps it can be charged to 105% all the time....

on a leased EV, let the next owner worry about the battery.

or is that wrong?

[Scrapula]

I charge to 90% on level 2. Our Lightning manual says 90% on level 2, 80% on level 3. The BMW design is different with a wound rotor synchronous motor which doesn’t use permanent magnets. I haven’t seen where charging would affect that motor differently.

But all manufacturers have extra capacity, not just BMW, so what the video says isn’t quite right.

[RichardInCA]

The nominal size of the battery seems to be ~84.4kWh but with 81.2kWh usable - in other words ~96%. Honestly, I don’t think this is rocket science - charge to 100% if you want to, the car won’t explode, but you risk reduced battery capacity over time.

It would really help if the author of the otherwise excellent i5 instruction video could provide more sources for his opinions - his bio is listed as being a BMW Genius at a North America location, but that tells me he’s signaling he knows what he’s talking about but that his advice is coming with a “your mileage might vary” disclaimer that he knows he is saying things that deviate from the script.

[SkykingUSA]

For me, it's an easy decision: do I listen to a YouTube video, or do I follow the owners manual? I go with the manual on this one. The manual clearly states what to do in the charging section.

Check out the recent post on this here: https://g60.bimmerpost.com/forums/sh....php?t=2073100

[deutsch100]

I had a Model Y Performance, and for 2021 Tesla told me to charge to 90% for daily use, 100% for a longer trip.

I Level I charge my i5 (same as I did with my iX, i4, i3, e-tron, I-Pace...) when my SOC gets to about 25-30%. I leave the i5 plugged in, until SOC is between 60-80%.

1-3x a month, I Level II charge to 100%.

This is how I have treated all my EVs and PHEVs, and I am very happy

[andykitty]

Originally Posted by deutsch100

I had a Model Y Performance, and for 2021 Tesla told me to charge to 90% for daily use, 100% for a longer trip.

I Level I charge my i5 (same as I did with my iX, i4, i3, e-tron, I-Pace...) when my SOC gets to about 25-30%. I leave the i5 plugged in, until SOC is between 60-80%.

1-3x a month, I Level II charge to 100%.

This is how I have treated all my EVs and PHEVs, and I am very happy

Do you mean level 2 and level 3 charging?

With level 1 charging, it would take about a week to charge from 30% to 80%

[deutsch100]

Originally Posted by andykitty

Do you mean level 2 and level 3 charging?

With level 1 charging, it would take about a week to charge from 30% to 80%

I might be in the minority, but I hate Level 3 (super charging). I'm sure once in a while is totally fine, but EA chargers are crap and I just think it's better for the battery to stick with Level I and II charging.

The reason I love Level I charging...it is "gentle" on the battery, and I can leave it plugged it for days if I am not driving, and little worry about hitting 100% SOC and then not driving it.

Level 1 from 30 to 80%...not a week, but it feels like it for sure! I was in the high 30s (SOC) when I plugged in to Level I last night before bed and by 8:30am, it was in the 50s (SOC).

[Theophilus]

I may be splitting hairs here, but BMW recommends charging up to 80% for “fast charging.” Is a Level 2 home charger maxed at 48 amps/11.5 watts considered “fast charging?” Or is that more like a DC public charger pushing 100+ watts? The 80% makes sense for public fast chargers, because the power curve is greatly reduced after 80%, thus making it infeasible for someone to remain plugged in and keep a charger busy for not much gain.

I purchased my car, but am tempted to charge to 90-95% for daily use, because I find the range generally disappointing compared to our i7 and Tesla Y.

[SkykingUSA]

Originally Posted by Theophilus

I may be splitting hairs here, but BMW recommends charging up to 80% for “fast charging.” Is a Level 2 home charger maxed at 48 amps/11.5 watts considered “fast charging?” Or is that more like a DC public charger pushing 100+ watts? The 80% makes sense for public fast chargers, because the power curve is greatly reduced after 80%, thus making it infeasible for someone to remain plugged in and keep a charger busy for not much gain.

I purchased my car, but am tempted to charge to 90-95% for daily use, because I find the range generally disappointing compared to our i7 and Tesla Y.

Fast charging is considered DC Fast Charging at the public locations which are usually 50 kW to 350 kW.

Level II charging is the 40 and 48 amp (9-11.5 kW) setups people install at home.

[AP]

This is a bit of a long read but it describes what causes a battery to age and therefore how to prolong its use

https://batteryuniversity.com/articl...ased-batteries

This article is geared to phone and similar type batteries , car batteries are arguably more sophisticated but I believe the basics still apply

In summary the range to keep a battery is between 65 and 75% and away from heat

What’s bad is leaving a battery deleted or fully charged

I also believe that the car battery reserve some captivity at either end to avoid this so when it states it’s 100% charged that is really a bit less day 95

[Scrapula]

Battery management has come a long way since early EVs. We are looking at 10 year old data at worst, 5 year old at best. You can never actually get to 100% on a battery because of the built in buffer. The old rule of 80% still lingers but more because of charging speed above 80% and etiquette.

[Trevor G]

Originally Posted by andykitty

Well, between a YouTuber/SA and the user’s manual, I believe what the manual says.

Have no desire to ever listen to what a youtubers personal opinions are. Wake up people and use your own minds. It is quite obvious you all have exceptional minds being able to afford a car this expensive. Make your own informed decisions.

[Trevor G]

I would suggest talking to a BMW Genius to get the proper information and not some unknown youtuber. BMW also has informational videos on youtube that are a good source straight from BMW.

[marsb007]

The dude doesn’t know his YouTube channel name is improper. Should be “Chris’ Bimmers”. Once I saw that, I literally didn’t watch the video any further, as clearly he’s not the best source of information…

Regardless, BMW warns you on the app, on the charging screen in the car, and in the manual to keep it lower than 80% for optimal battery longevity.

What more do you want?

Daily drives keep under 80-85%. Top off to 95-100% right before a longer trip if needed. Or just full send to 100% if you don’t care and you’re leasing.

Side note, had my iX in service for an update and they gave me another iX… charged to 100%. It probably had been sitting there for a while at 100%. When I returned the car to BMW I told them they should probably not charge to 100%. I did get a blank stare and that was clearly first they heard of it…

Also was shocked to learn it was dealership policy to make sure they charged the car to 100% upon delivery (they had to send a picture as proof). Even upon insisting that I do not want it charged to 100%, they reiterated they can’t turn the car over to me unless at 100%. I figured it would be at 100% for a very short time and it would be ok. Sometimes the path of least resistance is to not argue with idiots. They’ll drag you to their level and beat you with experience.

[RichardInCA]

Originally Posted by marsb007

Also was shocked to learn it was dealership policy to make sure they charged the car to 100% upon delivery (they had to send a picture as proof). Even upon insisting that I do not want it charged to 100%, they reiterated they can’t turn the car over to me unless at 100%. I figured it would be at 100% for a very short time and it would be ok. Sometimes the path of least resistance is to not argue with idiots. They’ll drag you to their level and beat you with experience.

Priceless - I’m guessing that they have enough new EV owners that it’s not worth the hassle of explaining why they won’t get a “full tank” when they pick up their car.

[MikeElmendorf]

My dealer told me the same thing on delivery—they need to document it was at 100% when delivered or they are penalized.

[Scrapula]

Same. I asked for 50%, enough to get me home and onto my own charger. Cannot deliver unless it is at 100% and was told that if I bring it in for service that it will be returned to me at 100%.

In reality, that 80% max has been myth busted a lot during the last year. It shouldn’t matter on new batteries.