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Hyundai Kona, Halfords bike
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Discussion Starter #1 (Edited)
I charged to 100%, now find I do not need the expected journey and will likely not need to use the car at all for a few days (or week/s maybe)

Might this cause any problems?
 

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I charged to 100%, now find I do not need the expected journey and will likely not need to use the car at all for a few days (or week/s maybe)

Might this cause any problems?
Have a look at BU-1003a: Battery Aging in an Electric Vehicle (EV) – Battery University

"SoC above 80% promotes capacity fade while a deep discharge increases the internal resistance. Li-ion must be shipped at 30% SoC; the recommended long-term storage is between 40–50%. Keeping Li-ion at high SoC affects battery life more than cycling in mid SoC range."

I would take it for a couple of laps around the block just to get the state of charge down a bit.
 

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I definitely wouldn't leave it for weeks. There's 'it will be fine' and there's taking sensible care of your very expensive car. It's generally advised to keep the battery between 20% and 80% and close to 50% if left for a longer period. It's not going to destroy the battery overnight, it just accelerates the degradation.
 

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Kia e-Niro MY20 64 kWh - Gravity Blue
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Agreed with the above. I would try to bring it down to 80%
 

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I would take it for a couple of laps around the block just to get the state of charge down a bit.
I'd say do that a couple of times a week in case it does turn out to be a long break. That will edge it down toward or into the 'comfort zone'.
It'll also help keep brakes and the like loose, especially if it lives outside.
 

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I suggest, if possible in your parking situation, that the car is turned on while parked and the heating and a/c turned up high with a couple of windows slightly open to give a through air flow for an hour or so. This will use some of the battery energy and also help keep the interior dry to reduce condensation/ dampness...
 

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Maserati Merak
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I definitely wouldn't leave it for weeks. There's 'it will be fine' and there's taking sensible care of your very expensive car. It's generally advised to keep the battery between 20% and 80% and close to 50% if left for a longer period. It's not going to destroy the battery overnight, it just accelerates the degradation.
And this is the right way to leave your battery :)
 

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Have a look at BU-1003a: Battery Aging in an Electric Vehicle (EV) – Battery University

"SoC above 80% promotes capacity fade while a deep discharge increases the internal resistance. Li-ion must be shipped at 30% SoC; the recommended long-term storage is between 40–50%. Keeping Li-ion at high SoC affects battery life more than cycling in mid SoC range."

I would take it for a couple of laps around the block just to get the state of charge down a bit.
Battery University is full of generalisations and hasn't a clue about the Kona BMS, ignore entirely😜
 

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Battery University is full of generalisations and hasn't a clue about the Kona BMS, ignore entirely😜
General principles of chemistry and physics still apply, even with the most sophisticated BMS to help mitigate any issues.

If you choose to ignore the advice that's fine. You'll probably suffer slightly accelerated degradation compared to people who pay a bit more attention to caring for their batteries. But please don't advise people to ignore the science just because you do.
 

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Battery University is full of generalisations and hasn't a clue about the Kona BMS, ignore entirely😜
OK. Try Tips to maintain your EV battery | Smart Home Charge




etc.

They will all tell you that leaving a lithium ion battery at 100% charge for any extended period of time will degrade the battery. If you are leasing your car or only keeping it for a year or two, then I don't suppose it will make much difference to you.
 

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General principles of chemistry and physics still apply, even with the most sophisticated BMS to help mitigate any issues.

If you choose to ignore the advice that's fine. You'll probably suffer slightly accelerated degradation compared to people who pay a bit more attention to caring for their batteries. But please don't advise people to ignore the science just because you do.
Oh dear, someone else who doesn't understand that the BMS dosn't allow the cells to be charged to the Battery University definitions or assumptions of 100%
 

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Kia e-Niro MY20 64 kWh - Gravity Blue
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Its everyting to do with the BMS dear chap. The BMS decides on the arbitrary setting of the 100% (which wont be 100% at all)
Considering the Kona battery only has a 5% buffer, it is anywhere between 95% and 100%, probably 97%. So you think it is OK to have Li-Ion sitting at 95% or 97% for prolonged periods?
 

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If you leave it too long without charging (or taking it for a run) then your 12 volt battery will go flat. Also, don’t forget that the BMS retains battery capacity and doesn’t charge to 100% nor does it allow complete discharge.
For all intents and purposes I would suggest ignoring the Battery University advice and follow the manufacturer‘s advice unless you plan to keep the vehicle for 150,000 miles plus. One day you will be half charged and need to do an extended run at short notice and have to wait a few hours to charge it up!
 

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KIA Soul EV 64kWh
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Oh dear, someone else who doesn't understand that the BMS dosn't allow the cells to be charged to the Battery University definitions or assumptions of 100%
Correct.
But indicated 100% is still higher than actual 80%.
There is some evidence that Li-Ion batteries should not be held at SOC >80%.

The advice to charge to indicated 80% in normal use still applies.

This advice is not mandatory and some people may not care even if it is harmful.
However to state that it is fine to charge to indicated 100% in all cases is almost certainly incorrect.
 

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I assume that there is a built-in protection that you cannot charge too much (90%) or too little (10%), I know if my car indicates 0% battery that it is therefore not empty ...
 
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