Power drain while parked

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Alexey

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Hi all, probably some of you had experience already or maybe you can point to a related thread. I'm going for long business trip and will need to keep Kona 64kWh parked for almost 3 weeks. Will it affect battery somehow? I heard that Nissan Leaf loses around 1% per day, what about Kona?
Thank you!
 
Alexey said:
Hi all, probably some of you had experience already or maybe you can point to a related thread. I'm going for long business trip and will need to keep Kona 64kWh parked for almost 3 weeks. Will it affect battery somehow? I heard that Nissan Leaf loses around 1% per day, what about Kona?
Thank you!
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I have read at least two reports of Kona Electric owners leaving their cars at the airport for about two weeks with no battery drain at all in the two week time frame.
 
I was reading the owner's manual today and it mentioned that you should recharge every 3 months (!) if you don't use the car, so it does seem that the battery will drain eventually. The manual recommends keeping the battery charge above 20%.
 
KonaTom said:
I left mine for 5 weeks with 2% loss
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Awesome!

Along with not letting the battery go flat, which sounds like it wouldn't easily happen, you also don't want to leave the battery charged to 100%. Sad experiences with laptops and remote control cars have taught me that these lithium batteries hate to be stored full or empty. In between is best.
 
eastpole said:
Awesome!

Along with not letting the battery go flat, which sounds like it wouldn't easily happen, you also don't want to leave the battery charged to 100%. Sad experiences with laptops and remote control cars have taught me that these lithium batteries hate to be stored full or empty. In between is best.
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Actually the Kona manual says to charge to 100% before long term storage. Presumably so the battery doesn't eventually go flat.
But apparently 100% on the dash is not really 100% at the battery. It may actually be only 90% or so.
 
brulaz said:
Actually the Kona manual says to charge to 100% before long term storage. Presumably so the battery doesn't eventually go flat.
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That is extremely bad advice. It's true that what the car reports as 100% is only 100% of the pack's usable capacity, not 100% of the full capacity, but it's still much too close to 100% to be good for battery life.

In fact, the shared wisdom is to never charge a BEV to 100% if you're not going to drive it within 24 hours. A fully charged BEV should not be left sitting for an extended period of time.

Conventional wisdom is to charge a BEV battery pack that's going to be sitting for a month or more to around 50-60% capacity (or drive the car until it's discharged to that level), and disconnect the starter battery. Of course not every BEV is designed the same way, so in most cases I'd say follow the instructions in the owner's manual. But if they're recommending charging to 100% before letting the car sit for an extended period, then that should be ignored.

If it's only 3 weeks then I'm not sure that you need to worry about the battery discharging too far, and previous comments in this discussion thread support that. (Fortunately your Kona doesn't experience anywhere near the amount of "vampire drain" that a Tesla car does.) I wouldn't let it sit for three weeks with a low charge, say 20% or below, but if it's somewhere between 30%-70%, I wouldn't think that it would have any measurable effect on the pack to sit for 3 weeks.

Recommended reading: "How to Prolong Lithium-based Batteries"
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The manual recommends charging to 100% at least once a month - I think this is for the BMS to balance the batteries.
I measured sleep mode 12V draw at 22-30mA, which is negligible, but there have been some reports of dead 12V batteries after a fairly short period, despite it getting topped up by the traction battery.
I have also seen the yellow-light indicating a top-up happen far more often than seems reasonable so there may be some situations where it drains more.
 
Actually it appears to suggest charging to 100% only if you allow the SoC to drop below 20%.
It's possible that cell balancing happens between an indicated 97 and 100%.
The two times I've charged to 100% in 8 months it jumps from 97 quickly to 100, I'd speculate that it's because nothing needs doing.
 
I parked my Kona saturday morning with 51% left and picked it up the following Tuesday evening withe the exact same amount of charge left. The car was parked indoor during those four days.


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Keeping in mind the resolution of only 1%. I often don't drive for several days at a time and don't see much worse but always see an aux battery charge message.
 
So I find this a bit odd. Yesterday I drove and plugged in afterward. The car charged to 100%. Tonight, even though I didn't drive, the car is charging ( at least the green ring is illuminated, the "battery" indicator isn't flashing). Blue link says it's at 100% with zero time remaining. Anybody suspect what's going on?

Update: ran for 40 minutes then charging stopped.
Weirder Update: Blue Link now reports that charging is "on" (though the charge port lights are off) and the charge has DROPPED to 99%! Curiouser and curiouser.
 
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You're going to drive yourself nuts trying to analyse the details around 100%! The percent readout seems to be a truncated reading meaning 99.99% reads 99% rather than 100. That's why it drops from 100 to 99 very shortly after you start driving away.
As long as an EVSE is plugged into the car and in the "ready" state, the car will take a charge (green light) whenever it sees fit - given the limiter and schedules settings. Also, note my speculation about cell balancing above.
 
GPM432 said:
What drains the 12volt battery when it is sitting and nothing running..
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Although the draw when the car is asleep is only about 11mA ( 25mA if "Welcome mirrrors" is enabled - this may not be an option on US/Can models), substantial amounts are drawn between turning the car off and it going fully to sleep. These shouldn't have significant impact on the traction battery, but will cause the 12V battery to be topped up fairly often, and that may be enough to push the display over a 1% threshold.
I've done some measurements :
https://www.speakev.com/threads/12v-battery-current-draw.141534/
I'm currently running a long-term voltage logger to look at long-term behaviour and frequency of top-ups.
 
My Kona is 3 months old located in New York State 75 miles north from NYC Picture taken July 10 2019 outside temp 88 F garage kept with temperature 75 F
 

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Just to be safe, I did purchase a 12 V battery charger that I will keep in my car. I never want to be left stranded because my 12 V battery has drained.
 
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