Balance charging

[Gadget Geek]

My car is a gen1 and the chsrger was ready to go. In fact on connecting it did appear to charge for a very short time (say 10 seconds) before displaying "connected but not charging". But my question is, does the balancing protocol only start after a period of proper charging?

Once it reaches 100%, it then starts to alter the voltages on the individual cells until they all have the same voltage. It's quite a complex procedure which is controlled by the BMS (Battery Management System).

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[Tim Green]

But my question is, does the balancing protocol only start after a period of proper charging?

 

[Jomarkh]

But my question is, does the balancing protocol only start after a period of proper charging?

It will balance every time if left connected after 100% is reached.

 

[Gadget Geek]

But my question is, does the balancing protocol only start after a period of proper charging?

Yes. When it reaches 100%.

 

[peterseddon]

Well, charged to 100% last night and activated "allow charging after schedule" so it would balance. got up this morning and checked on me house energy monitoring software and it just stopped at 100%. I the opened ISmart and it immediately started charging again. No mater what I did with the app it wouldn't stop charging, the app said it had but it was still pulling 6kW. Had to go to the car and start it up then stop it charging from the screen. Very strange, and I still don't know if it balanced or not.

 

[Lovemyev]

Well, charged to 100% last night and activated "allow charging after schedule" so it would balance. got up this morning and checked on me house energy monitoring software and it just stopped at 100%. I the opened ISmart and it immediately started charging again. No mater what I did with the app it wouldn't stop charging, the app said it had but it was still pulling 6kW. Had to go to the car and start it up then stop it charging from the screen. Very strange, and I still don't know if it balanced or not.

That’s a bit odd ? ?.
If it started charging again and it was pulling 6 kW, then you would have to suggest the battery was not at 100% even though it said it was ?.
How long did you allow it to keep on charging again, until you then manually stopped it ?.
Maybe it would have pulled 6 kW for a very short time, then dropped back quick there after ?.
I guess the only way to be sure what is going on, is now the car is at a high state of charge, is to plug it back in again ( day light hours ) when you can observe first hand what is happening.
You home energy monitor will provide the evidence.
I conducted a similar study when my battery was at about 75% and I set the charge level to 80%.
I put the car back on charge in the day.
I wanted to try and catch the car performing a so called balance cycle at this level.
I could not find any evidence of this happening.
I would be very interested to hear what you find at 100% if you decide to go ahead ?.

 

[peterseddon]

That’s a bit odd ? ?.
If it started charging again and it was pulling 6 kw’s, then you would have to suggest the battery was not at 100% even though it said it was ?.
How long did you allow it to keep on charging again, until you then manually stopped it ?.
Maybe it would have pulled 6 kw’s for a very short time, then dropped back quick there after ?.
I guess the only way to be sure what is going on, is now the car is at a high state of charge, is to plug it back in again ( day light hours ) when you can observe first hand what is happening.
You home energy monitor will provide the evidence.
I conducted a similar study when my battery was at about 75% and I set the charge level to 80%.
I put the car back on charge in the day.
I wanted to try and catch the car performing a so called balance cycle at this level.
I could not find any evidence of this happening.
I would be very interested to hear what you find at 100 if you decide to go ahead ?.

It's absolutely persisting it down at the moment so I'll wait till a better day. I had to stop it twice using the app, but as soon as I tried to see what it was doing it started charging again.

 

[Chrisjk]

MG recommend that a balance cycle should be carried out once a month, as a very rough guide.
The length of time it actually takes to balance the pack, is another story completely.

2nd gen EV LR
Hi, last night long charge over7 hours when it started from 47%
8 am today, 100% and 247 miles. Decided to charge another hour re balancing, showed charging at 4.7kW, but after another hour still 100% and 247 miles. does that prove balancing has happened?

 

[Tim Green]

Probably, but I am surprised at the power requirement to balance, if that is all that was happening….

 

[Lovemyev]

2nd gen EV LR
Hi, last night long charge over7 hours when it started from 47%
8 am today, 100% and 247 miles. Decided to charge another hour re balancing, showed charging at 4.7kW, but after another hour still 100% and 247 miles. does that prove balancing has happened?

Given that the car was on charge for 7 hours, from a SOC level of 47% - then I would suspect that any balancing that WAS required, happened within that first 7 hour charge ?.
The PREDICTED range at 100% SOC of 247 miles, may suggest that your accumulated trip had not been reset to zero, prior to charging maybe ?.
I am a little puzzled why the car was pulling 4.7 kW TBH on the second attempt to carry out a balance cycle.
Did you manually stop the second charge after one hour ?.
What was the coloured charging lights displaying in the charge port at this point ?.
The normal pattern for the balance cycle on the ZS EV Gen1 was as follows.
When the battery reached 100% SOC THEN the balance cycle would commence, the draw from the wall box reduced to 3.5 kW then down to around 950 (ish) watts, then stepped down in gradual phases of 500 - 300 then finally down to 175 watts before finishing, soon after by returning the wall box to the standby mode.
I am unable to confirm if the Gen2 model behaves in a similar manor.

 

[Chrisjk]

Thanks again for all that very helpful information.
Acc. trip NOT reset. Didn’t know it was necessary. Will always do it now
I too was surprised about 4.7 kw pull. It stopped charging on its own
Didn’t check lights colour. Does it show a different colour when balancing completed?
Chris

 

[drmcw]

Trip reset isn't necessary unless you want to lose all the accumulated driving history. There's nothing the car does to tell you that balancing has been completed, you just have to trust the BMS. I'm guessing that the high power draws that people are seeing at 100% when re-starting a charge are down to battery heating as the battery will have cooled down and the BMS should be doing it's job and ensuring its not charging a cold battery.

 

[Lovemyev]

Thanks again for all that very helpful information.
Acc. trip NOT reset. Didn’t know it was necessary. Will always do it now
I too was surprised about 4.7 kw pull. It stopped charging on its own
Didn’t check lights colour. Does it show a different colour when balancing completed?
Chris

Resetting the trips is not something you have to do, it is purely an individuals 100% choice for you to make Chris.
I have always reset my trips myself, but that’s my preferred choice.
You just have to remember, that what your car predicts in range after a full charge, is purely that, it’s a prediction and not factual.
So why bother resetting then ?.
IF you do reset your trips and then charge, you car should report something close to the stated range given by the manufacturer.
As a rough estimate you are looking at at 212 miles of predicted range at 80% SOC and 270(ish) at 100% SOC.
This WILL be very much temperature dependant of course.
There is no right and wrong way, only your personal choice.
Sorry, I can’t offer any views regarding charge port light colours when balancing.
I did a careful study of the previous model, but have never caught the Gen2 balancing yet !.
My charging is all done at night on an off peak rate.
The day rate is way too expensive for carrying out random testing ?.

 

[asandrews]

I have the 73 plate ZS EV Trophy LR and almost always charge at home on a Zappi2.1 controlled by IOG Smart charging schedules which typically are set to charge by 05:30 am.

Even though I always ask for a bit more than I need (just to be safe) and charge to 100% I never see a significant period of 'trickle charging'. Take last night where it appears to have finished at 04:15.

Do I need to use the Granny charger for balancing?

Ta.

 

[Lovemyev]

You can balance from any A/C supply.

 

[DB Go Rex]

I have the 73 plate ZS EV Trophy LR and almost always charge at home on a Zappi2.1 controlled by IOG Smart charging schedules which typically are set to charge by 05:30 am.

Even though I always ask for a bit more than I need (just to be safe) and charge to 100% I never see a significant period of 'trickle charging'. Take last night where it appears to have finished at 04:15.

Do I need to use the Granny charger for balancing?

Ta.View attachment 24670

If you aren't doing much rapid charging and are taking it to 100% and back down on a reasonably regular basis there's likely not much need for it.

I would not worry and just drive the car.

 

[profdraper]

Gen 2: when the front port light is blue,the car is still charging on full power; when it is green it is balancing on trickle charge; when the light goes out it is done.

 

[BeardedZs]

We only have a granny charger which serves us well, most of the time. ZS Trophy LR gen 2. 23 plate. A balancing charge at "granny" rate takes a very long time if we take it down to as near-zero as possible before going up to 100%. Does anyone know, (and I have looked!) if it is necessary to go that low before charging and if so do we have to charge it up again in one go? (Cheap rate overnight adds around 17%). Does using the car in-between charges confuse the BMS? Is this the winning argument in the "should we get a charger" discussion??

 

[DB Go Rex]

We only have a granny charger which serves us well, most of the time. ZS Trophy LR gen 2. 23 plate. A balancing charge at "granny" rate takes a very long time of we take it down to as near-zero as possible before going up to 100%. Does anyone know, (and I have looked!) if it is necessary to go that low before charging and if so do we have to charge it up again in one go? (Cheap rate overnight ads around 17%). Does using the car in-between charges confuse the BMS? Is this the winning argument in the"should we get a charger" discussion??

No to the questions on going to zero and BMS confusion.

You should get a dedicated charger for safety and convenience though.

 

[fred12345]

We only have a granny charger which serves us well, most of the time. ZS Trophy LR gen 2. 23 plate. A balancing charge at "granny" rate takes a very long time of we take it down to as near-zero as possible before going up to 100%. Does anyone know, (and I have looked!) if it is necessary to go that low before charging and if so do we have to charge it up again in one go? (Cheap rate overnight ads around 17%). Does using the car in-between charges confuse the BMS? Is this the winning argument in the"should we get a charger" discussion??

There are few threads in the last few days on the subject of 10% to 100%, balancing and whether it's needed...I decided to do it every few months when convenient, on my 3-pin charger...