Do I charge to 80% or 100%?

Sophiameow

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Hi everyone,I'm excited to share that I'll be receiving my first EV, the MG4, this week. However, I have some questions about the charging process.Can I safely charge my car to 100% all the time? I've noticed that many people recommend charging only up to 80% and avoiding 100%, but I'm not sure which battery is in my car. I have the 51 kWh standard range version, and I am from the UK, if that helps.

May I also ask, Is it safe to always charge my car? For example, if the battery is at 65%, can I charge it to full, or should I wait until the battery percentage drops to around 10%? I will be driving approximately 40 miles each day, so the battery percentage will drop daily. Should I wait until it gets low to charge, or can I charge it every day regardless of the current battery percentage?

I really appreciate everyone's help ☺️ ?
 
Jerry Pan and cars has a youtube video on the topic.
It's a highly personal opinionated topic so I'll refrain from commenting otherwise
 
I'm not an expert but from what I've read and seen online if you have the standard car (SE) you can charge to 100% daily and this shouldn't be a problem.

The Trophy on the otherhand should be charged to 80% for daily use, and 100% for long range trips.

Others may have differing opinions though, hope you enjoy the car!
 
If you look in the car (or the iSmart app) you'll find that the 51 kWh version doesn't have a setting to limit the maximum state of charge (SoC). Ergo charging to 100% every time is not a problem. (I've had mine over 19 months and I've almost always charged to 100%, except when using a DC rapid charger).
 
Hi everyone,I'm excited to share that I'll be receiving my first EV, the MG4, this week. However, I have some questions about the charging process.Can I safely charge my car to 100% all the time? I've noticed that many people recommend charging only up to 80% and avoiding 100%, but I'm not sure which battery is in my car. I have the 51 kWh standard range version, and I am from the UK, if that helps.

May I also ask, Is it safe to always charge my car? For example, if the battery is at 65%, can I charge it to full, or should I wait until the battery percentage drops to around 10%? I will be driving approximately 40 miles each day, so the battery percentage will drop daily. Should I wait until it gets low to charge, or can I charge it every day regardless of the current battery percentage?

I really appreciate everyone's help ☺️ ?
The 51kWh battery (unlike the others) is LFP chemistry which is the most rugged type of battery, so it is generally considered ok to go to 100%.

Our home battery is LFP and goes to 100% and down to 10% each day.

Apparently you are supposed to run the MG battery low (below 10%) and then charge it all the way to 100% every few months to allow the battery management system to balance and assess the cells. But I haven't managed to successfully do that as yet after four+ months.

Personally, I plan to look out for what days have greener energy (more wind/sun) and charge then. Octopus has a webpage that suggests the best day to charge.

But otherwise do what is convenient!
 
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It is indicated that you are supposed to let the battery balance once a month at 100%. (it is written on the granny cable IIRC)

Anyway, the consensus is that charging up to 100% is, as the other said, harmless for the 51kWh LFP battery, but there is still an advantage to not charge it over 80%.

The regen braking is very poor once 90%, so less efficient driving, and one-pedal mode is locked over 80%.

As for how low you should allow the battery is go is debatable, I'm on the lithium battery shouldn't go under 30% side.
 
Treat it like your phone - charge when you can (or whenever its cheap to do so). If you are not on a smart-tariff for your electric, its worth looking at (check out Octopus) if you plan to mostly charge at home.
 
May I also ask, Is it safe to always charge my car? For example, if the battery is at 65%, can I charge it to full, or should I wait until the battery percentage drops to around 10%? I will be driving approximately 40 miles each day, so the battery percentage will drop daily. Should I wait until it gets low to charge, or can I charge it every day regardless of the current battery percentage?

I really appreciate everyone's help ☺️ ?

You've got the same as me, the 51kWh pack which is Lithium-Iron-Phosphate (LFP) and is the more durable but less dense option.

It is always "safe" to charge the car up in the sense that you can't do that much damage or wear to it in any meaningful timespan, so don't stress too hard about it! It just happens that (all) lithium based batteries endure more degradation at low and high states of charge, in an S-curve shape. So going all the way down to 0% or up to 100% is fine in the short term, but avoid leaving the car sat in that state for a long time if you can!

If you're driving every day, you're using that energy, so you can comfortably charge to 100% every night and the wear on the battery will be minimal. You can also charge to 80% if you really really want to baby it and you'll see even less wear, but I honestly don't know how noticeable the difference will be in the end.

Some interesting videos to check out:


Skip to 14:14 to get right to the meat of the question about "damaging" the battery

 
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You've got the same as me, the 51kWh pack which is Lithium-Iron-Phosphate (LFP) and is the more durable but less dense option.

It is always "safe" to charge the car up in the sense that you can't do that much damage or wear to it in any meaningful timespan, so don't stress too hard about it! It just happens that (all) lithium based batteries endure more degradation at low and high states of charge, in an S-curve shape. So going all the way down to 0% or up to 100% is fine in the short term, but avoid leaving the car sat in that state for a long time if you can!

If you're driving every day, you're using that energy, so you can comfortably charge to 100% every night and the wear on the battery will be minimal. You can also charge to 80% if you really really want to baby it and you'll see even less wear, but I honestly don't know how noticeable the difference will be in the end.

Some interesting videos to check out:


Skip to 14:14 to get right to the meat of the question about "damaging" the battery


'The manufacturer won't allow you to damage the battery...' THIS is the truth!
 
As others have said with the battery in the 51 kWh car 100% is fine but unless you need to I’d not charge back to 100% every night (the manual recommends you charge to 100% at least once a week). You don’t get regenerative breaking at high states of charge nor will one pedal driving turn on and leaving the car for a long periods (days) at 100% isn’t great for the battery.

I don’t normally plug back in until the battery is at around 20 - 30 % unless I need the range for something. Also as others have mentioned, about once every 6 months you need to let it go down below 10% and fully charge so the battery management system can continue to accurately determine the battery capacity.

Don’t stress about it though. Unless you plan on keeping the car for a very long time the only way you could really do damage is letting it get to 0% and leaving it like that.
 
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'The manufacturer won't allow you to damage the battery...' THIS is the truth!
It isn’t. The LFP battery only has a very small bottom buffer and leaving it for long periods at 0% can irreversibly damage the battery. The manual states that if the car displays no valid range and is not charged to 50% with 7 days it invalidates the warranty.
 
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I have an LFP home battery system:

1719948067711.png


I'd say that IF the MG4 LFP system behaves the same as this, then charge it up to 100% each month, as it brings each pack capacilty back in line - my current system hasn't touched the grid for the last few months (house & MG4), but its getting a little out of shape, which a full grid charge sorts out.
 
Hi everyone,I'm excited to share that I'll be receiving my first EV, the MG4, this week. However, I have some questions about the charging process.Can I safely charge my car to 100% all the time? I've noticed that many people recommend charging only up to 80% and avoiding 100%, but I'm not sure which battery is in my car. I have the 51 kWh standard range version, and I am from the UK, if that helps.

May I also ask, Is it safe to always charge my car? For example, if the battery is at 65%, can I charge it to full, or should I wait until the battery percentage drops to around 10%? I will be driving approximately 40 miles each day, so the battery percentage will drop daily. Should I wait until it gets low to charge, or can I charge it every day regardless of the current battery percentage?

I really appreciate everyone's help ☺️ ?
Hi I have a 51 and MG say it’s ok to charge to 100% and the 64 charge to 80% and 100% every month ?
 
I have the same car and battery, and as stated 100% charge stops the regen, there's no where for the regen current to go.
But unlike the previous poster, I can engage one pedal driving at 92%, it doesn't need to drop to 80%. And I think regen at a lower level will automatically start around 95%.

Lack of regen can be a tad disconcerting if you haven't regularly charged to 100%.
I try to avoid it as I really like one pedal driving.
 
You've got the same as me, the 51kWh pack which is Lithium-Iron-Phosphate (LFP) and is the more durable but less dense option.

It is always "safe" to charge the car up in the sense that you can't do that much damage or wear to it in any meaningful timespan, so don't stress too hard about it! It just happens that (all) lithium based batteries endure more degradation at low and high states of charge, in an S-curve shape. So going all the way down to 0% or up to 100% is fine in the short term, but avoid leaving the car sat in that state for a long time if you can!

If you're driving every day, you're using that energy, so you can comfortably charge to 100% every night and the wear on the battery will be minimal. You can also charge to 80% if you really really want to baby it and you'll see even less wear, but I honestly don't know how noticeable the difference will be in the end.

Some interesting videos to check out:


Skip to 14:14 to get right to the meat of the question about "damaging" the battery


Thank you. Does that mean I can pretty much charge my car everyday regardless of what the current battery percentage is? And charge it to 100%
 
Thank you. Does that mean I can pretty much charge my car everyday regardless of what the current battery percentage is? And charge it to 100%
Yes but if you are like most of us and love regen you will want it below about 90% so that you can get the benefit.

Regen is one of the best things about electric cars - you get about 20% of your energy back instead of losing it to brake heat (and pollution)!
 
Yes but if you are like most of us and love regen you will want it below about 90% so that you can get the benefit.

Regen is one of the best things about electric cars - you get about 20% of your energy back instead of losing it to brake heat (and pollution)!
AHH what is this regen?how does it work? So you get 20% of battery back?
 

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