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Hi all - real newbie question: as long as no-one is waiting to use a public rapid charger, can I simply leave it on charge to get to 100% or close to? I've read that the charge time increasingly slows after 80%, but does it damage the battery in anyway? Thanks.
 

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It charges VERY Slowly as you get to the top end of the battery. You're also adding extra unnecessary heat and not allowing the cells to balance like they would on AC charging. It's definitely preferable not to regularly rapid charge to 100% for reasons other than blocking up a charger for others.
 

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Good lord no!!!

Battery degradation as above, and just because it looks empty does not mean someone is just about to drive in to use it, see it’s taken and have to locate another.

If we all block rapids like this when you really need one they’ll be someone sat there an hour to get to 100% !
 

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It charges VERY Slowly as you get to the top end of the battery. You're also adding extra unnecessary heat and not allowing the cells to balance like they would on AC charging. It's definitely preferable not to regularly rapid charge to 100% for reasons other than blocking up a charger for others.
Thanks. So best not to charge up to 100% on rapid then.
 

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Good lord no!!!

Battery degradation as above, and just because it looks empty does not mean someone is just about to drive in to use it, see it’s taken and have to locate another.

If we all block rapids like this when you really need one they’ll be someone sat there an hour to get to 100% !
OK thanks, so bad idea even if the rapid charger is not needed (our local one doesn't get heavy use), and better to charge up to 80% on rapid then do the remainder at home on a slow charge if I need to get to 100% for a long drive the next day - sound good?
 

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You’ll get a feel for when your car slows and the temp gauge. I found LeafSpy amazing for looking how much rapids shockingly heat your pack up!

I stop before it gets too hot even if not 80% and I can make it home at that
 

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............ better to charge up to 80% on rapid then do the remainder at home on a slow charge if I need to get to 100% for a long drive the next day - sound good?
If you have overnight home charging available then the 'best' is to only use a Rapid to get you enough electrons to get home to plug in there. Stop charging when you have enough to get home. Never mind up to 80% in most cases. Costs less and saves you sitting around for half an hour watching the seconds click by. Why buy up to 80% at Rapid prices and waste personal time?

The many debates over 100% charging over the years have rarely been able to provide serious evidence of battery harm as long as the car isn't left at full charge for weeks.

But it can easily take longer to go from 80% to 100% on a Rapid as it takes to go from empty to 80%. The charge rate drops off to below the home charge rate the nearer to 100% it gets. I've known faster glaciers. Then, as has been mentioned, simply sitting there sipping electrons can cause other users to abort a visit as they drive by and not realise that you would exit if they stopped. So, for many reasons, it's best to leave at 80%, or better yet, at much below that unless you definitely need more.
 

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OK thanks, so bad idea even if the rapid charger is not needed (our local one doesn't get heavy use), and better to charge up to 80% on rapid then do the remainder at home on a slow charge if I need to get to 100% for a long drive the next day - sound good?
Is there any reason why you wouldn't just do all your charging at home? It's more convenient and is going to be cheaper than public charging especially if you get off peak energy deals.

Especially with such a small battery, even at slow 3kw charging you're going to easily get from empty to 100% overnight without needing a rapid charge to help speed things up.
 

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Battery balancing has nothing to do with AC or DC charging.
Last 10% will take very long time as charge rate drops to AC charging rate.

If you let it run all the way, it will finish just like on AC.

DC charging however pushes temperature of battery so not advisable on daily basis

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Battery balancing has nothing to do with AC or DC charging.
On the LEAF balancing takes place at 100% which is why the lights still flash for a while once its fully charged. I've only allowed my car to do this twice but both times I left it on a rapid charger it stopped at 98%. That would mean it can't do the balancing process on DC if it stops just before full.
 

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On the LEAF balancing takes place at 100% which is why the lights still flash for a while once its fully charged. I've only allowed my car to do this twice but both times I left it on a rapid charger it stopped at 98%. That would mean it can't do the balancing process on DC if it stops just before full.
That would depend on the charger. I have seen units stop charge at 90%

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Li-ion battery charging system employs
Constant current until desired cell / pack voltage is reached.

Once pack voltage is reached, the charging system switched to constant voltage that keeps going into charging current drops below certain level.

BMS is configured to run when pack voltage is achieved.

The onboard AC charger concerts 240VAC to DC and is DC charging that actually charges the car.


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OK thanks, so bad idea even if the rapid charger is not needed (our local one doesn't get heavy use), and better to charge up to 80% on rapid then do the remainder at home on a slow charge if I need to get to 100% for a long drive the next day - sound good?
Unless your local rapid is free (price), why bother use it at all?

EV ownership is simple, plug it in overnight. Forget the petrol station refuel model.

As said, Leaf has a small battery and there's no problem getting a full charge doesn't matter the charge rate. Even the 2kW granny charger can charge the Leaf empty to full overnight.
 

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Unless your local rapid is free (price), why bother use it at all?

EV ownership is simple, plug it in overnight. Forget the petrol station refuel model.

As said, Leaf has a small battery and there's no problem getting a full charge doesn't matter the charge rate. Even the 2kW granny charger can charge the Leaf empty to full overnight.
Even if that rapid is free, you’ll soon notice that it becomes inconvenient soon. In late 2018 to early 2019, I rapid charged once a week. For last year, I haven’t rapid charged very often and they are mostly paid.


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I cannot even be bothered to drive to Nissan now for free charging, the £1 I save from not charging at home is not worth my time!
 

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I cannot even be bothered to drive to Nissan now for free charging, the £1 I save from not charging at home is not worth my time!
Me neither. My nearest charger is £1 + 0.30/kWh and I've used that the last few times

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I have a 30, which doesnt slow as much as a 24, but i have on a few occasions charged to fairly high SoC without really trying.

Last weekend for instance, i parked at a Tesco in Dunblane and plugged into the rapid, waited a few minutes for my brother to arrive, went into the store, got stuff for a picnic, used the lav, sorted the kids out and went back out to the car, loaded the shopping in, and stopped the charger. Car was at 97% and had been on charge for 27 or 28 minutes. As it happened the extra 15% came in quite useful, as i arrived home that day with the low battery warning on.

Theres a lot of gnashing of teeth on here about charging, but really its just being sensible. I didnt particularly want to charge to 97%, i just stopped, did what i had to do and returned to the car within a sensible time (for a rapid) and there it was. I was actually surprised that a) it had actually taken 30minutes to get a small number of bits from the shop, and b) the car had reached such high SoC given everyone goes on about it slowing down. I wasnt going to run out the store after 14.57minutes to remove the car from the charger because it had reached 80.01% (or whatever).

I've had similar experiences a few times in a similar manner, where i've stopped for lunch/rest stop near a convenient charger, plugged it in while i've had food and returned to a full battery. And i'm fairly happy doing that. If its going to be longer than ~30mins, i'll try to arrange a different solution or get back to move the car etc. But i also know if the charge does finish, someone else can start one as the car releases the cable. Its certainly much less annoying than the guy i came across later the same day who'd plugged his BMW PHEV into the Rapid in Callander for 2 hours, right beside two 7kw posts... At least Scottish chargers allow simultaneous AC and DC charging so it didnt actually stop me using it.

So to answer your direct question, no, its not a problem charging to 100%, just dont be a knob. If theres folk waiting, move on. As for some of the other more nuanced points, i mostly agree with the others, using a public rapid when you have charging facilities at home is daft, unless it happens to fit with something your doing anyway the tiny saving is just not worth the time.
 

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If its going to be longer than ~30mins, i'll try to arrange a different solution or get back to move the car etc. But i also know if the charge does finish, someone else can start one as the car releases the cable.
This is the key. Be considerate at rapid chargers.

Chademo has also got this right. The plug is attached to the charger, not car owner's property. So once finished charging, the plug unlocks and allows other people to use it. CCS behaves the same as Type 2, meaning the cable is locked even if it has finished charging, annoying those waiting for a charge due to owner being inconsiderate and not moving their vehicle.
 
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