Charging my first EV MG4

[Tuareg]

Of course they're true. It's the same studies that determined 80% cap is pretty beneficial, which resulted to all manufacturers recommending their users to daily charge at that. Before that, early EVs like leaf always charged to 100%. As that wasn't studied that well 15 years ago. And we all know what happend to those batteries long term.

Don't believe what you read on internet 'studies' as most of that is rubbish. The manufacturer provides the guidelines in the owners manual and does not state any restriction on charging. Otherwise, they would have made 80% read as 100%.

It's a car, it's there to be driven within the manufacturers guidelines which are specified in the manufacturers documentation, not spurious internet 'studies'. Just like the rumours spread about EVs bursting into flames.

 

[Jamesrr]

I'm not interested in getting into any flame wars. That being said, the iSmart app specifically calls setting the charge level at 80% "Health mode" and 100% "Long journey mode".

Charging set to 80%

"Health Mode"

Set the target level to 100%

I have an NMC battery in our "77" and the "64" batteries are also NMC. When I'm taking the car on long distance trips interstate I swap it to 100% to allow full charging.

When back and just doing normal driving I put it back to 80% and leave it there.

My wife's car has the 51 LFP battery so we just leave it at 100% because that battery tech is unaffected by charging to 100% every time.

It's of trivial effort and can't hurt.

 

[ReintjeWA]

Also not willing to be part of the flame wars, I would like to add this study to the mix;

Existing EV batteries may last up to 40% longer than expected

Consumers’ real-world stop-and-go driving of electric vehicles benefits batteries more than the steady use simulated in almost all laboratory tests of new battery designs, Stanford-SLAC study finds.

news.stanford.edu

It shows that a lot of things we think we know about EV-batteries are based on ICE-thinking testing, which doesn’t stack up.

 

[Corindikev]

When I bought my Essence 64 in September 2023 I read all the different reports about charging and battery degradation I could find and charged when I got to about 20% or less to 80% regularly & 100% once a month. Then I found out it was a good idea to get down to 10% or less a few times a year.

Then I watched an informative video posted on this site by Dr Euan McTurk and later articles on how batteries were lasting way longer than the experts originally thought, plus articles of owners who had done huge mileages over a number of years (500,000 and more km) on the same battery with no issues.

Charging to 100% is fine even for NMC batteries but don't let the car sit at 100% for weeks or months on end. Dr MckTurk explains this well. Degradation occurs when the battery sits at a very high state of charge over time. This is partly the reason that for daily normal operation just charge to 80% unless you need the extra range. Also the last 20% is slow compared to the first 80%. This is to preserve battery health when charged via a DC supercharger. At home you are slow charging anyway so it doesn't matter.

Now I don't have any regime at all and just charge at home from my 7kW wall EVSE when I need to & when I get free power from the electricity retailer or when it is sunny & I get power from my solar panels. The cars internal management software balances the cells automatically whenever the charge setting is set from 60% up to 100%.

 

[wattmatters]

If that was the case, the owner's manual would have specified the internet myth of '80%' but they don't

The user manual will not feature many items the car might provide with software and other updates. Indeed the manual itself clearly states this:

As to charging of NMC models...

MG include a drive battery charge mode indicator for NMC models called:
"Health Mode", and
"Long-Trip mode"

You can select the SOC charge limit using either the car's central control panel or via the iSmart app.

Health mode is indicated when charging is limited to no more than 80%. This is the default and suitable for day to day driving.

"Long Trip mode" is when charging limit is set higher (up to 100%) and doing so every so often is a good idea, just don't leave it that way for a long time.

You may also choose other SOC charge limits.

 

[hojnikb]

Don't believe what you read on internet 'studies' as most of that is rubbish. The manufacturer provides the guidelines in the owners manual and does not state any restriction on charging. Otherwise, they would have made 80% read as 100%.

It's a car, it's there to be driven within the manufacturers guidelines which are specified in the manufacturers documentation, not spurious internet 'studies'. Just like the rumours spread about EVs bursting into flames.

Are you really saying accredited and peer reviewed studies are rubbish?

Manufacturers provides guidelines that are not necesserly best for the car.

A good case in point are 30kkm oil changes. Everyone knows those are bad for your car long term.

And just to throw some gasoline to the fire; Even SAIC itself indirectly says to you that charging 40-80% is best for your battery. Note the green line that says "Battery health mode"

 

[pjmmk]

Android have jumped on board the 80% thing as well, their phones now stop charging at 80%. You can turn that off for a full charge if you want to but it's well accepted that lithium-ion batteries don't like deep discharges or full charges. That's not to say you can't do it, just don't do it all the time and certainly don't leave a near fully discharged or fully charged battery for long periods.

 

[Tuareg]

Always charged my phones to 100%, current Xiaomi lasts to about 90% standby time from new after 5 years and that's much older tech with a lot less battery management.

With regards to the MG, always charge for as long as I have time for, often it allows up to 100%.

 

[ReintjeWA]

Apple does this too, lets you select certain percentages between 80 and 100. And it does this thing where it learns when you tend to start using your phone, and won’t go to 100% before you need it.

I wonder if a smaller battery (like in a phone) suffers more from full charging/discharging than a big battery (like a car). Or maybe it’s just that say 10% degradation is more noticeable on a smaller capacity.

 

[Rolfe]

My Android phone has had that capability for ages.

 

[Corindikev]

Compared to an EV battery phone batteries are very simple and there are 2 major types Lithium ion (Li ion) & Lithium polymer (Li-po) & have very basic management software, mostly just a slow down rate at the top which is why some have a feature to stop at 80%. Li ion has better energy density, last longer & are cheaper. Li-Po has a higher discharge rate & are lighter.

My current Redmi 13 Pro with Li-ion battery has a 67 watt charger & will charge from empty to full in 44 minutes but will charge to 50% in 17 minutes. It gets quite warm and if the fast charger is used it should not be charged in a case in order to dissipate the heat.

The Li-ion battery in my old LG phone is still good after 8 years. The software is way out of date now. Just like EVs, the battery will outlast the car & also the phone. I always charged to 100% with the old & also with the new phone.

 

[hojnikb]

Apple does this too, lets you select certain percentages between 80 and 100. And it does this thing where it learns when you tend to start using your phone, and won’t go to 100% before you need it.

I wonder if a smaller battery (like in a phone) suffers more from full charging/discharging than a big battery (like a car). Or maybe it’s just that say 10% degradation is more noticeable on a smaller capacity.

View attachment 36884

Phones are mor susceptible to degradation, because they're using chemistry that's optimized for high energy density instead of high cycle life. And usually, they run hotter, as they are passive cooled and usually close to the cpu. And they rapidcharge very fast; some much higher C rate than cars.

But one thing phone batteries have going for them is calander aging. As rarely anyone keeps their phone for more than 4-5 years, that usually isn't that big of a factor. And usually there's only one cell, so no issues with balancing.

Compared to an EV battery phone batteries are very simple and there are 2 major types Lithium ion (Li ion) & Lithium polymer (Li-po) & have very basic management software, mostly just a slow down rate at the top which is why some have a feature to stop at 80%. Li ion has better energy density, last longer & are cheaper. Li-Po has a higher discharge rate & are lighter.

My current Redmi 13 Pro with Li-ion battery has a 67 watt charger & will charge from empty to full in 44 minutes but will charge to 50% in 17 minutes. It gets quite warm and if the fast charger is used it should not be charged in a case in order to dissipate the heat.

The Li-ion battery in my old LG phone is still good after 8 years. The software is way out of date now. Just like EVs, the battery will outlast the car & also the phone. I always charged to 100% with the old & also with the new phone.

Lithium polymer is just a subset of lithium-ion. And most if not all phones actually use lithium polymer.

And BMS in a phone is actually pretty advanced. Short of balancing feature (as it's not needed) its on par with EVs in terms of complexity.

Unfortunally, with most phones that are actually used, battery will be EOL long before phone is useless.

 

[MG Clive]

Roll on Solid State EV Batteries.

 

[pjmmk]

My Android phone has had that capability for ages.

That's relatively new for mine. It appeared with an update several months ago.

 

[siteguru]

Mine still doesn't have it. (Xiaomi Redmi Note 13 Pro+ running HyperOS2/Android 15). My laptop does though.