Overcharging beyond 100% ???

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CBEAR30

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MG4 SE SR
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I have an MG4 standard SE
Electricity Tariff is 29.61 per kWh (rubbish - I already know)

Last night I used my Podpoint homecharger app set on a schedule of 4.5hrs, while also having my MG app set to just manually charge at the same time - usually just use the MG App as never any issues with it and didnt fully trust the pod app. I completely forgot the car was charging and only realised to stop the charger an hr later than planned. It had gave an estimate that the car would be fully charged at 21.40ish on the MG app.
Q. Does this reading mean (see photo image) my car charged to 100% at 4hrs 33 and as I didn't stop it (or stop the manual MG app) it continued to charge for another hr at 100%?

Does anyone know if there is a time period were it stops charging at 100% for safety?

Sorry if these are daft questions maths and common sense not my strong points :/
 
First thing. Get yourself on an EV tariff 😁

Don't set a charging schedule on the wall charger and the iSmart/car app as it confuses the electronic handshakes etc.

It was probably doing a balance charge once it hit 100%. This can take anything from a few minutes to nearly a couple of hours to complete depending on when it was last done. The car will only draw a few watts while it does this.
 
Ian Key said:
First thing. Get yourself on an EV tariff 😁

Don't set a charging schedule on the wall charger and the iSmart/car app as it confuses the electronic handshakes etc.

It was probably doing a balance charge once it hit 100%. This can take anything from a few minutes to nearly a couple of hours to complete depending on when it was last done. The car will only draw a few watts while it does this.
Click to expand...
OP is in Northern Ireland. Not sure if there are any EV tariffs there!
 
My SE SR always goes on for another 30-35 minutes after reaching 100%, which is the balance charge period. I haven't seen it do as much as an hour, but then I let it do this every time I charge. Maybe it takes longer if it hasn't been done for a wee while.

I also noticed once or twice that it on the app it would extend its estimated finish time by half an hour or so once it was at about 99%, and the charging power would fluctuate for the last half hour of charging, before the balance charge started. Someone else explained to me that this was happening because the car had decided it needed to heat the battery as it approached 100%, and it was diverting power from the granny lead to the battery heater, hence the fluctuating charge wattage.
 
And an EV tariff is (usually) only relevant IF you're also prepared to time-shift other heavy usage (e.g. washing machine, tumble dryer, dishwasher); if you're not then the higher peak rate of such tariffs may well end up costing you more. (Or at least offset any EV charging saving thus making the tariff irrelevant). :)
 
Ian Key said:
First thing. Get yourself on an EV tariff 😁

Don't set a charging schedule on the wall charger and the iSmart/car app as it confuses the electronic handshakes etc.

It was probably doing a balance charge once it hit 100%. This can take anything from a few minutes to nearly a couple of hours to complete depending on when it was last done. The car will only draw a few watts while it does this.
Click to expand...
OK that's great to know thanks, I only got the home charger recently and I've only charged it to 100 about four times since. I got it last Aug and preferred the supercharger over the granny 😅

Is there anywhere you can find more info on 'balancing'? The MG manual info is vague on this.

Tariff options not great in NI, can only avoid meter readings for so long 🙈
 
That makes sense mine took longer as hasn't been balanced before. Do you really need to balance it every time you charge to 100%? It just doesn't suggest this anywhere in the manual, I've googled and read this was important with older models but not so with recent ones but on chats a lot seem to recommended it.
 
Rolfe said:
My SE SR always goes on for another 30-35 minutes after reaching 100%, which is the balance charge period. I haven't seen it do as much as an hour, but then I let it do this every time I charge. Maybe it takes longer if it hasn't been done for a wee while.

I also noticed once or twice that it on the app it would extend its estimated finish time by half an hour or so once it was at about 99%, and the charging power would fluctuate for the last half hour of charging, before the balance charge started. Someone else explained to me that this was happening because the car had decided it needed to heat the battery as it approached 100%, and it was diverting power from the granny lead to the battery heater, hence the fluctuating charge wattage.
Click to expand...
That makes sense mine took longer as hasn't been balanced before. Do you really need to balance it every time you charge to 100%? It just doesn't suggest this anywhere in the manual, I've googled and read this was important with older models but not so with recent ones but on chats a lot seem to recommended it.
 
The manual is more relevant to the NMC battery and we have the LFP battery. The car will balance itself every time you get to 100% unless you actually stop the charge. There is no reason to do that because it's only drawing about 20 watts.

Make the most of the LFP. No need to worry about charging only to 80%, just whack it up to 100% every time you're charging on AC, and let it do its thing. Interesting that it takes longer if it hasn't been balanced for a while. You may see your range increase a little after that. I have never seen mine not balance when taken to 100%, even five days in a row. It likes it.

The other thing you need to do every few months is run the car down to under 10% and then do a long charge to 100% and balance. This is important for the calibration of the mileage estimate. If you don't do it. you're opening yourself up to seeing your remaining range drop by 10 or 20 miles when you're on a motorway with no exits, and the car has seen the bottom 10% and realised it's got a lot less in hand than it thought.

Regular balancing plus a long charge at least every six months keeps everything happy.
 
You can tell from the app. During the balancing period the EV management screen shows that the car is charging, and that the % charge is 100%. At the bottom of the screen the "Finishing Time" displayed will be the same as the current clock time and the "Charging Power" will say 0.0 kw. (In the old version of the app it would say 0.02 kw, which is how I know it's drawing 20 watts - with the occasional spike a bit higher.)

Once the balancing is done the screen changes to say "Not charging". At the bottom the range will be displayed, but next to it there will only be "--" against "Finishing Time" and "Charging Power". The car is done. Full to bursting and burping. Normally it takes 30-35 minutes from reaching full (you can see the charging power dropping) to finishing balancing.

It doesn't matter if you have to stop the charge early, but the advice is to let it do the balancing thing at least once a week.

I didn't know any of this when I got the car, but the good people on this forum educated me. I was still thinking I should only charge to 80% because I'd seen too much advice aimed at people with NMC batteries, and the dealer's explanation was a bit perfunctory. (He was right, he said just whack it up to 100% whenever you like, but he didn't explain that I had been misled by advice meant for the other battery chemistry.)
 
Rolfe said:
You can tell from the app. During the balancing period the EV management screen shows that the car is charging, and that the % charge is 100%. At the bottom of the screen the "Finishing Time" displayed will be the same as the current clock time and the "Charging Power" will say 0.0 kw. (In the old version of the app it would say 0.02 kw, which is how I know it's drawing 20 watts - with the occasional spike a bit higher.)

Once the balancing is done the screen changes to say "Not charging". At the bottom the range will be displayed, but next to it there will only be "--" against "Finishing Time" and "Charging Power". The car is done. Full to bursting and burping. Normally it takes 30-35 minutes from reaching full (you can see the charging power dropping) to finishing balancing.

It doesn't matter if you have to stop the charge early, but the advice is to let it do the balancing thing at least once a week.

I didn't know any of this when I got the car, but the good people on this forum educated me. I was still thinking I should only charge to 80% because I'd seen too much advice aimed at people with NMC batteries, and the dealer's explanation was a bit perfunctory. (He was right, he said just whack it up to 100% whenever you like, but he didn't explain that I had been misled by advice meant for the other battery chemistry.)
Click to expand...
Thanks so much for this 😊
 
@siteguru Not sure about other tariffs, but on my Octopus Go, there is no longer a loading on the day time rate to compensate for the 9p 12.30 - 04.30 one.
I do still run my power hungry appliances overnight, whenever practicable though.
 
JeffMcC75 said:
Its getting better, but yeah not much competition. I dont think Click Energy can be beaten at the moment.

I am with Click Energy Click Energy - Northern Ireland's Low-cost Electricity Company. Its 26.9p per unit on its 24hr tariff.
Night tariff is 15p per unit night and 35p per unit day

PowerNI has its EV Tariff : Electric vehicle Tariffs NI | Green Electricity | Power NI 15.5p night and 32.4p day, 24hr rate of 29.3p.
Click to expand...
 
JeffMcC75 said:
Its getting better, but yeah not much competition. I dont think Click Energy can be beaten at the moment.

I am with Click Energy Click Energy - Northern Ireland's Low-cost Electricity Company. Its 26.9p per unit on its 24hr tariff.
Night tariff is 15p per unit night and 35p per unit day

PowerNI has its EV Tariff : Electric vehicle Tariffs NI | Green Electricity | Power NI 15.5p night and 32.4p day, 24hr rate of 29.3p.
Click to expand...
Click Energy is definitely the best, I'm stuck on PowerNI 24hr rate until I get an an actual meter reading and pay any additional costs incured 🫣 ....have prioritised other things as life is for living but will do this soon and then I'll happily wave bye bye to PowerNI 😅
 

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