Are there guidelines about battery management?

StuartT

Established Member
Joined
Aug 3, 2023
Messages
84
Reaction score
61
Points
34
Location
Oxford
Driving
MG4 Trophy LR
I am aware that modern batteries tend to have preferences about charging practice in order to maximise battery life (such as never go below x% charge, or don't charge all the way to 100% etc)

I have been though the manual but can't seem to find this. All I found is that you should mostly slow charge, not rapid charge.

Does anyone have any advice about percentages though? Or are these batteries pretty tolerant?

Thanks

(I have a '23 Trophy by the way)
 
Trophy = 64kWh NMC battery = typically keep within 20-80% (i.e. charge to 80%), but charge to 100% if you're going to need the range the next day, and charge to 100% at least once per month to allow the BMS (Battery Management System) to balance the battery cells.
 
Trophy = 64kWh NMC battery = typically keep within 20-80% (i.e. charge to 80%), but charge to 100% if you're going to need the range the next day, and charge to 100% at least once per month to allow the BMS (Battery Management System) to balance the battery cells.
perfect! Thanks (y)
 
Trophy = 64kWh NMC battery = typically keep within 20-80% (i.e. charge to 80%), but charge to 100% if you're going to need the range the next day, and charge to 100% at least once per month to allow the BMS (Battery Management System) to balance the battery cells.
@siteguru and others, I would appreciate your suggestion for my scenario below,

My return journey for a day to work is 160miles and I do that twice a week regularly. I have got Long range trophy and it's been about two weeks. I have been charging 100% pervious evening with home charge Type2 6.45 kW charging power. Stays on 100% overnight and leave arou 6:30am. I have noticed I have left about 30% charge with 100miles range. My driving style almost as fast as speed limits except traffic jams on M25.

is charging from 25-30% to 100% twice a week for long range trophy not good? And this is summer time I am sure during winter I might have to top up a bit during work or during return journey.

I would appreciate your suggestions. Thanks
 
The batteries in the LR (NMC batteries) don't like being left at 100% but as you are using the car within a few hours of reaching full charge it shouldn't be a problem.
Once a month it might be an idea to leave the car on charge after it reaches 100% for an hour just to let it do a balancing charge.
 
@siteguru and others, I would appreciate your suggestion for my scenario below,

My return journey for a day to work is 160miles and I do that twice a week regularly. I have got Long range trophy and it's been about two weeks. I have been charging 100% pervious evening with home charge Type2 6.45 kW charging power. Stays on 100% overnight and leave arou 6:30am. I have noticed I have left about 30% charge with 100miles range. My driving style almost as fast as speed limits except traffic jams on M25.

is charging from 25-30% to 100% twice a week for long range trophy not good? And this is summer time I am sure during winter I might have to top up a bit during work or during return journey.

I would appreciate your suggestions. Thanks
It's fine, you're making good use of the battery. Obviously it will be expected to degrade a bit faster than one that is not used as much but we buy the cars to be used.

One thing you could do is set the timers in the car so that charging has just completed before setting off. That way it will spend less time at 100% and there will be some extra warmth from the charging process in the battery which is helpful in winter.
 
I am aware that modern batteries tend to have preferences about charging practice in order to maximise battery life (such as never go below x% charge, or don't charge all the way to 100% etc)

I have been though the manual but can't seem to find this. All I found is that you should mostly slow charge, not rapid charge.

Does anyone have any advice about percentages though? Or are these batteries pretty tolerant?

Thanks

(I have a '23 Trophy by the way)
Here is a very recent video from “Petrol Ped” that offers a good explanation of EV batteries.

 
I got my car delivered yesterday and straight away did a 100% charge & balance. My daily commute is 80-90 miles depending on any traffic rerouting, from 4 to 6 times a week if I do any extra shifts. I did 87 miles yesterday, purposely driven exactly the same as I did in my ice Mazda the day before, and I've got 61% battery left. If indeed I have 20% left after tonight's shift I'll charge to 100% again and if the numbers repeat I'll probably commit to charging to 95% every 2 days instead to lessen any premature chance of degradation to give me a 15% battery buffer should the s#!t hit the fan on any of my commutes. I'm probably being overcautious with only charging to 95% going off reports & videos from genuine battery experts rather than scaremongers, I'll always be driving the car within several hours of reaching 95% charge.

Edit: I've just had my first play with the MG scheduled charging options and it'll only increase/decrease in 10% increments so I'll be either charging to 100% each time or doing a bit of basic maths to schedule my charging finish times to end when it should be around 95%
 
Last edited:
I got my car delivered yesterday and straight away did a 100% charge & balance. My daily commute is 80-90 miles depending on any traffic rerouting, from 4 to 6 times a week if I do any extra shifts. I did 87 miles yesterday, purposely driven exactly the same as I did in my ice Mazda the day before, and I've got 61% battery left. If indeed I have 20% left after tonight's shift I'll charge to 100% again and if the numbers repeat I'll probably commit to charging to 95% every 2 days instead to lessen any premature chance of degradation to give me a 15% battery buffer should the s#!t hit the fan on any of my commutes. I'm probably being overcautious with only charging to 95% going off reports & videos from genuine battery experts rather than scaremongers, I'll always be driving the car within several hours of reaching 95% charge.

Edit: I've just had my first play with the MG scheduled charging options and it'll only increase/decrease in 10% increments so I'll be either charging to 100% each time or doing a bit of basic maths to schedule my charging finish times to end when it should be around 95%
What model do you have ?.
 
Thanks everyone for your suggestions. Btw while we are at this, do we need to schedule pre-heating battery before charging (recommended 1.5hrs before charging)in summer. In this case for charging period between 11:30pm to 6:30am. Hot day like today temperature is in the range of 12-15 c during that night times. What's the happy temperature range for the Mg4 trophy long range battery? Or is this functionality for winter only?
 
Last edited:
Thanks everyone for your suggestions. Btw while we are at this, do we need to schedule pre-heating battery before charging (recommended 1.5hrs before charging)in summer. In this case for charging period between 11:30pm to 6:30am. Hot day like today temperature is in the range of 12-15 c during that night times. What's the happy temperature range for the Mg4 trophy long range battery? Or is this functionality for winter only?
Pre heating isn't necessary for home charging at all. In the winter it will help you with Rapid charger speeds en route but even then, if you do a long drive before your first stop the battery will heat up anyway, so in practice we rarely use it. Most useful case is in cold winter if you are low on charge and need to rapid charge early in your journey,
 
@siteguru and others, I would appreciate your suggestion for my scenario below,

My return journey for a day to work is 160miles and I do that twice a week regularly. I have got Long range trophy and it's been about two weeks. I have been charging 100% pervious evening with home charge Type2 6.45 kW charging power. Stays on 100% overnight and leave arou 6:30am. I have noticed I have left about 30% charge with 100miles range. My driving style almost as fast as speed limits except traffic jams on M25.

is charging from 25-30% to 100% twice a week for long range trophy not good? And this is summer time I am sure during winter I might have to top up a bit during work or during return journey.

I would appreciate your suggestions. Thanks
You can comfortably do 160 miles on 80% though, right?
So since you're on a convenient home charger follow MG's advice and charge to 80%.

I think obsessing over battery care is overkill (like an ICE driver checking their oil before every journey). But if the manufacturer is telling you 100% can cause harm, why do that routinely when it's not necessary?

As the weather gets colder, see how it affects your SOC when you get home and adjust accordingly, but I think 80% ought to work year-round.
 
What's the happy temperature range for the Mg4 trophy long range battery? Or is this functionality for winter only?
By and large, I would say yes, winter time.
But this feature is useful for use if you are going to be using a D/C rapid charger.
Bringing up the pack to the ideal temperature in order for the car to receive the highest charging speed possible, is the general basic idea.
But remember, you get nothing for nothing.
The battery heating reduces he remaining range in you battery !.
You have to make the call on its use.
 

Are you enjoying your MG4?

  • Yes

    Votes: 544 79.3%
  • I'm in the middle

    Votes: 91 13.3%
  • No

    Votes: 51 7.4%
Support us by becoming a Premium Member

Latest MG EVs video

MG3 Hybrid+ & Cyberster Configurator News + hot topics from the MG EVs forums
Subscribe to our YouTube channel
Back
Top Bottom