Battery Balancing

[Cabansail]

When talking to the original owner he said that he had only charged above 80% a few times, and this was on a DC Rapid Charger when doing a longer trip.

I imagine that means the battery has never been balanced. Today I hope to do just that. The sun is out today, so plenty of solar.

Had to go into town early this morning, so charged it to 90% before driving home. Now it's plugged into the power and slow charging to 100%. Hopefully this will work.

 

[decrep]

What is your model?
There's a difference between the 51kWh models and the rest.
The 51 has to go to 100% and left until charging until the car says it's finished charging, don't stop charging because it's hit 100%
The other models with NMC batteries, apparently can balance when they reach set to stop value, but I'm not clear on that.

 

[Cabansail]

Hi @decrep - It's the Xpower.

I found this YT video interesting.

 

[decrep]

So it's the NMC battery, at the moment there's another thread about this.

M

Thread 'Equalisation charge - NMC battery'

Wednesday at 1:05 PM

Two questions please:

1. Has it been clarified yet whether a full equalisation charge is achieved with an NMC battery at 80%? (or will that only happen at 100%?)

2. Is it possible to achieve a full equalisation charge (at either 80% or 100%) using scheduled charging - or will the charge terminate as soon as the charge gets to the specified charge level, without maintaining the charge connection so as to achieve the balancing? (Reason for this is to balance during off-peak power - in the middle of the night when I'm not able to watch the charge rate)

• MarkHoward
• mg4
• Replies: 39
• Forum: MG4 EV Forum

• 

What I can gather from this is that you can balance from a "standard charge" IE set in health mode to 80% max, but it has to be done at a rate of 11kW or less. a DC charger is no use for this.
You should see a display on the car screen that says balancing just after it hits 80%, don't finish the charge until the car says it's finished.

 

[salty]

I just charge my X Power when I want, to what I want. And I'm pretty sure, it'll make
no difference whatsoever on the health of the battery. Only my opinion of course.

 

[Tuareg]

Same here. I own the car, the car doesn't own me, something many seem to forget and sleep walk into.

 

[MG Clive]

I charge mine when I have free leccy, I have 12 hours free on Sunday, so it'll get a full charge.

 

[Tuareg]

My energy costs bugger all, all day long, €0.04 per kw, so €2.56 (£2.22), so theoretically to charge from 0-64kw, a full 'tank'. I charge when I need to top up.

 

[Lovemyev]

The S5 and the ZS EV LR both have NMC battery technology.
After owning both models of the ZS before switching to the S5 - this has been my personal observations.
The original ZS would only enter the balance cycle after it had reached 100% SOC.
I have witnessed the balance cycle start and complete on my home energy monitor.
At about 98% the draw from the wall box reduces slowly from 7kw’s down to 3.5kw’s for a short while, then progressively ramps down to about 750 - 500 and completing after a short spell of about 100 watts.
Then the contactors in the wall box will open.
Mostly I would charge to 80% SOC and I have seen NO evidence to suggest that it balances after hitting the 80% target.
It just abruptly stops.
The facelift version ( with no surprise, is the same ).
In my opinion, the pack has to be first at 100% before the BMS can calculate IF a balance cycle is necessary, it does this by calculating the difference in the cell voltages and makes a choose from this.
This what changes the length of the balance cycle times.

 

[bedsev]

I just charge my X Power when I want, to what I want. And I'm pretty sure, it'll make
no difference whatsoever on the health of the battery. Only my opinion of course.

Same

 

[EvilSeagull]

I just charge my X Power when I want, to what I want. And I'm pretty sure, it'll make
no difference whatsoever on the health of the battery. Only my opinion of course.

You're 100% right my friend.
Unless you bought this car with intent to keep it til 200-300k miles - it literally makes no difference.

 

[Chrisdriving]

BMS balances regardless, cell delta constantly managed, you can see this real time on the Leaf for example when running Leaf spy.
Had my MG4 for 1 year and only charged it to 100% once in all that time, cell delta is fine.