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Kia e-Niro MY20 64 kWh - Gravity Blue
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That’s a conscious choice by Kia, which is fine, but just confirms my point that a BMS can balance individual cells at less than 100%.

I get that Kia call it 100% for ease of understanding by customers, when it’s actually 90% in reality.
Yes, but it will NOT do it while charging to lower percentages than the (virtual) 100%.

I also believe you're overly optimistic about the top buffer. It's a generally accepted fact that the e-Niro has a gross capacity of 67 kWh. So 100% SoC will be closer to 97% than 90%. Good thing is though that the NCM622 chemistry has a better resistance to high SoC than NCM811.
 

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ID.4 GTX & M3 LR
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Yes, but it will NOT do it while charging to lower percentages than the (virtual) 100%.
Yes, you said, but it’s actually less than 100%, so regardless of what the manual says the BMS is balancing at less than maximum charge, which is all I said.

It’s common for a modern BMS to be capable of balancing cells at less than an actual 100%, the ID.3 manual makes no mention of it, just to charge to only 80% unless you need the extra range.

I also believe you're overly optimistic about the top buffer. It's a generally accepted fact that the e-Niro has a gross capacity of 67 kWh. So 100% SoC will be closer to 97% than 90%. Good thing is though that the NCM622 chemistry has a better resistance to high SoC than NCM811.
We’re talking about the EV6, I don’t own one but the info posted seems to suggest the maths is right.
 

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Which manufacturer is advising charging to 100% regularly to ‘balance cells’?

And how does that square with the fact that you can’t charge a BEV pack to 100% anyway, Tesla excepted?

Ergo, the BMS can balance at less than 100%.
At less than 99% all voltages are more or less the same across cells, so balancing is only effectively possible at 98-100% .
Not that would make any dent to the life of the battery if one cell is at 45% and the other at 46%
 

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Audi eTron 55
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At less than 99% all voltages are more or less the same across cells, so balancing is only effectively possible at 98-100% .
Not that would make any dent to the life of the battery if one cell is at 45% and the other at 46%
I don't think that's true. Voltage changes most rapidly at lower states of charge and levels off towards the end. Balancing is totally up to the BMS designer, it is nothing to do with an absolute cell condition.
 
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ID.4 GTX & M3 LR
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At less than 99% all voltages are more or less the same across cells, so balancing is only effectively possible at 98-100% .
Not that would make any dent to the life of the battery if one cell is at 45% and the other at 46%
Whether you ‘balance’ cells at 4.1v or 3.8v, doesn’t really matter, and my point was that BMSs have moved on in the last decade and they certainly can balance at different voltages.

Personally, I just think this is a subject that far too many EV owners worry about, and the way it’s often written about is just another little barrier to adoption for anybody reading about them on here for the first time.
 

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It's better for battery longevity to charge 10% min to 80% max than it is 20% min to 90% max. Me, I tend to keep the charge between 30 and 70% in my e-niro
Prove that statement!

There is no evidence that these urban charging myths have any basis in fact on the latest EVs with better battery management systems.

Any suggestions in the vehicle handbook are provided entirely to reduce any possibility of a battery warranty claim and I would question the need to buy an EV with a larger battery than you need and only using 60% of it.

Even the advice not to leave the battery at a vey low or high level for a long period is probably not applicable due to the buffers at top and bottom. Again.where is the evidence to back up this advice?
 

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Prove that statement!

There is no evidence that these urban charging myths have any basis in fact on the latest EVs with better battery management systems.

Any suggestions in the vehicle handbook are provided entirely to reduce any possibility of a battery warranty claim and I would question the need to buy an EV with a larger battery than you need and only using 60% of it.

Even the advice not to leave the battery at a vey low or high level for a long period is probably not applicable due to the buffers at top and bottom. Again.where is the evidence to back up this advice?
Agree with FarmerGiles. In any case at what temperatures is the advice applicable?
 

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I used to charge my I-Pace to 100% on the 7kW charger most times I plugged in. It was also occasionally run down to 5% or less. At 42,000 miles and 3 and a bit years it was giving same range as when it was new (adjusting for temperature).
However, I’d generally avoided going over 90% on rapid chargers. And those were the days when 50kW was rapid 😊
 

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otally up to the BMS des
cars dont get that "LOW" to see those differences.what your dash says as "0%" is like 10-15%, so from 15% to high 90s, your voltage difference between cells will be next to none.
Voltage difference is essential for fast and effective balancing, if you look into any lithium SOC graph and understand how an active balancer works, will be pretty obvious to you.
 

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Whether you ‘balance’ cells at 4.1v or 3.8v, doesn’t really matter, and my point was that BMSs have moved on in the last decade and they certainly can balance at different voltages.

Personally, I just think this is a subject that far too many EV owners worry about, and the way it’s often written about is just another little barrier to adoption for anybody reading about them on here for the first time.
My point is that at 99% one cell can be 100% and the other at 98%. which can be a difference in voltage of 0.4v or more.
At 50% one cell can be at 48% and another at 53% and the voltage difference between them will be 0.008v
Voltage difference is essential for balancing to work, and most BMS's will only do this at high state of charge for that same reason.
 
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