Nissan Leaf

13-10-2017 9:02pm

NIMAN wrote: »

Does it draw less electricity when balancing I assume?

yes, much less.

n97 mini · 13-10-2017 9:04pm

NIMAN wrote: »

Does it draw less electricity when balancing I assume?

My understanding of balancing (see other thread) is that stronger cells are discharged to level with weaker cells. It's not smart balancing so that discharge is wasted (as opposed to going into other cells). This happens regardless of whether the car is plugged in or not.

I've yet to understand if there is any benefit to being plugged in while balancing is going on.

13-10-2017 9:20pm

Balancing only happens at charging.

When the car is active the BMS is there to hold cells that are too low. It does not really balance. But it's always active. The real balancing happens only at charging.

Soarer · 14-10-2017 4:03am

Deleted User wrote: »

Don't forget NOT to set an end timer, and end timer will mean charging ends at that time whether it's finished charging/balancing or not.

That's not right.

The only way to guarantee you get 100% and balanced is to set an end timer only.
That way, it'll start charging at whatever time it sees fit in order to be finished by the end time.

I've my end timer only set to 08:15 every day, and I usually get an "end charge" notification around 07:40 to say she's finished.

Orebro · 14-10-2017 9:51am

Soarer wrote: »

That's not right.

The only way to guarantee you get 100% and balanced is to set an end timer only.
That way, it'll start charging at whatever time it sees fit in order to be finished by the end time.

I've my end timer only set to 08:15 every day, and I usually get an "end charge" notification around 07:40 to say she's finished.

That’s what I thought Soarer but sometimes mine seems to need longer than the set end time to completely finish (from experimenting myself) - maybe it depends on how imbalanced the pack is? I’m guessing if you let it complete like yours every night then it’s balanced well, but with mine where I don’t charge it to 100% every day it needs a couple of hours longer to complete.

KCross · 14-10-2017 10:33am

danoriordan1402 wrote: »

silly question as I am new to all this - if a Leaf is charged up to max, take off the charge point and left for say 4-5hrs. Would there be much difference in the battery charge/

None.
I'v gone on holidays for 2 weeks and there was no change in the battery % when I came back. Im sure it was down a few Wh's but not enough to change the % on the display.

NIMAN wrote: »

So say I set it to be charged for me at 6am, does it build all these calculations into its start time?

Yes, it does for me anyway. Just set an end time only (no start time) and the car will figure it out.

n97 mini wrote: »

My understanding of balancing (see other thread) is that stronger cells are discharged to level with weaker cells. It's not smart balancing so that discharge is wasted (as opposed to going into other cells). This happens regardless of whether the car is plugged in or not.

I've yet to understand if there is any benefit to being plugged in while balancing is going on.

Im not sure that is what the balancing does. The balancing happens at the end of the charging and it is using small amounts of power from the charge point to do it so presumably it is taking on power, not discharging.

As I understand it, the shunts you see in LeafSpy are the stronger cells "passing" charge to the weaker cells and then the battery takes on more charge to topup again and it keeps repeating until it gets an even charge across all cells.

It doesn't make sense that it would just discharge strong cells to get down to the same level as the weakest cells.... there wold be nothing to gain from that only capacity loss.

Soarer wrote: »

That's not right.

The only way to guarantee you get 100% and balanced is to set an end timer only.
That way, it'll start charging at whatever time it sees fit in order to be finished by the end time.

I've my end timer only set to 08:15 every day, and I usually get an "end charge" notification around 07:40 to say she's finished.

I agree. That works for me too.
The other way to guarantee 100% charge is just set a very early start time but it makes more sense to just set an end time only and let the car figure it out. I always end up with 100% on the dash with that configuration.

Orebro wrote: »

That’s what I thought Soarer but sometimes mine seems to need longer than the set end time to completely finish (from experimenting myself) - maybe it depends on how imbalanced the pack is? I’m guessing if you let it complete like yours every night then it’s balanced well, but with mine where I don’t charge it to 100% every day it needs a couple of hours longer to complete.

And that happens when you only have an end time set, no start time?

Do you also have preheating timed? That will affect the cars ability to get to 100% depending on how you have that configured. Maybe its that, not balancing.

14-10-2017 1:24pm

Soarer wrote: »

That's not right.

The only way to guarantee you get 100% and balanced is to set an end timer only.
That way, it'll start charging at whatever time it sees fit in order to be finished by the end time.

I've my end timer only set to 08:15 every day, and I usually get an "end charge" notification around 07:40 to say she's finished.

No you're wrong. The end timer ends at that time, balanced or not.

You set start timer, usually when the off peak leccy kicks in then don't set end timer because you know most if not all the charging will be done before peak rate kicks back in.

n97 mini · 14-10-2017 1:48pm

KCross wrote: »

Im not sure that is what the balancing does. The balancing happens at the end of the charging and it is using small amounts of power from the charge point to do it so presumably it is taking on power, not discharging.

As I understand it, the shunts you see in LeafSpy are the stronger cells "passing" charge to the weaker cells and then the battery takes on more charge to topup again and it keeps repeating until it gets an even charge across all cells.

It doesn't make sense that it would just discharge strong cells to get down to the same level as the weakest cells.... there wold be nothing to gain from that only capacity loss.

Read this post:
http://www.mynissanleaf.com/viewtopic.php?f=30&t=15627&start=10#p350041

Worth noting Leaf does not discharge strong cells into weak cells (aka intelligent balancing) but instead bleeds them off via resistors.

KCross · 14-10-2017 2:48pm

The following seems more believable to me, but I'm not a battery expert either so it's hard to tell what Nissan have actually implemented.

https://speakev.com/threads/battery-balancing-whats-it-for.19104

So it's not discharging high voltage cells, it's just not taking on charge to the cells that have hit cutoff voltage and hence shunting to the resistor while the lower voltage cells do take on charge to get upto the same level as the high voltage cells.

Soarer · 14-10-2017 7:05pm

Deleted User wrote: »

No you're wrong. The end timer ends at that time, balanced or not.

You set start timer, usually when the off peak leccy kicks in then don't set end timer because you know most if not all the charging will be done before peak rate kicks back in.

You can say I'm wrong if you want, but I'm not.

Yes, the end timer will end at that time, but only if you've set a start time. If you haven't, it will start early enough to have everything done.

I've explained exactly what happens with my car EVERY DAY! I don't have a start time set, only end time. I don't care about peak and off peak rates. Maybe that's what's clouding your judgment?! That you can only charge within certain times?

As far as I'm concerned, and from my personal experience, not setting a start time and ONLY setting an end time will give you a full charged, fully balanced, battery. Mine finishes everything about 40 minutes before the end time setting kicks in.

Do you really think, with all the technology in the Leaf, that Nissan would've got the timers wrong?

14-10-2017 8:20pm

Soarer wrote: »

I don't care about peak and off peak rates.

Oh right, I suppose I never conceived the idea someone might not want to avail of off peak charging.

14-10-2017 8:25pm

KCross wrote: »

The following seems more believable to me, but I'm not a battery expert either so it's hard to tell what Nissan have actually implemented.

https://speakev.com/threads/battery-balancing-whats-it-for.19104

So it's not discharging high voltage cells, it's just not taking on charge to the cells that have hit cutoff voltage and hence shunting to the resistor while the lower voltage cells do take on charge to get upto the same level as the high voltage cells.

Pretty standard BMS behaviour. Nothing unique to the Leaf really. Same with my Ebike batteries. Or Lipo packs, though these balanced on the charger itself.

Soarer · 14-10-2017 10:26pm

Deleted User wrote: »

Oh right, I suppose I never conceived the idea someone might not want to avail of off peak charging.

The cost of charging is irrelevant to what we're talking about.

The car will start charging at whatever time it sees fit, to finish at the time you tell it to.

n97 mini · 15-10-2017 3:30pm

KCross wrote: »

The following seems more believable to me, but I'm not a battery expert either so it's hard to tell what Nissan have actually implemented.

https://speakev.com/threads/battery-balancing-whats-it-for.19104

So it's not discharging high voltage cells, it's just not taking on charge to the cells that have hit cutoff voltage and hence shunting to the resistor while the lower voltage cells do take on charge to get upto the same level as the high voltage cells.

That's for the Tesla Model S, which probably does things differently.

NIMAN · 07-11-2017 8:57pm

n97 mini wrote: »

That's for the Tesla Model S, which probably does things differently.

Digging the old Leaf thread back up, as I have another general question. It ls quicker to ask here and go out in the cold and read the manual!

I have just set my car to do timed charging for the 1St time.

When you plug it into the charge point and power that up, do the 3 blue charging lights flash in sequence?

KCross · 07-11-2017 9:08pm

NIMAN wrote: »

Digging the old Leaf thread back up, as I have another general question. It ls quicker to ask here and go out in the cold and read the manual!

I have just set my car to do timed charging for the 1St time.

When you plug it into the charge point and power that up, do the 3 blue charging lights flash in sequence?

Yes, for a few mins only and then they should all go off until the timer kicks in.

Water John · 07-11-2017 10:35pm

Driving through Dunmanway this evening. It has a number of speed readers.

Comparing car speedo to actual reading
52kph

44kph
47kph

41kph

07-11-2017 10:54pm

Most cars read about 5-6 Kph less.

Soarer · 07-11-2017 11:04pm

Mine is normally about 10% ahead of those speed radars.

NIMAN · 08-11-2017 4:39pm

KCross wrote: »

Yes, for a few mins only and then they should all go off until the timer kicks in.

All worked fine.
Always a worry that you might come out to a flat car in the morning.

DrPhilG · 08-11-2017 6:16pm

NIMAN wrote: »

All worked fine.
Always a worry that you might come out to a flat car in the morning.

Especially now that the Derry FCP seems to have properly shlt the bed.

NIMAN · 09-11-2017 12:57am

DrPhilG wrote: »

Especially now that the Derry FCP seems to have properly shlt the bed.

?

DrPhilG · 09-11-2017 1:09am

NIMAN wrote: »

?

Derry FCP has been temperamental for months, now failed completely and marked out of action on the ESB map.

NIMAN · 09-11-2017 8:41am

Which one is that?

DrPhilG · 09-11-2017 10:15am

NIMAN wrote: »

Which one is that?

Only fast charger in Derry!

Glendermot road Maxol station.

NIMAN · 09-11-2017 10:58pm

Only ever tried that one once, it was OOO.

Firblog · 09-11-2017 11:39pm

DrPhilG wrote: »

Derry FCP has been temperamental for months, now failed completely and marked out of action on the ESB map.

The fast charger in Kee's Petrol Station in Laghey (outside Donegal Town) has been out of service for weeks now, got caught twice going out there without checking first... :mad:

DrPhilG · 10-11-2017 1:06am

Firblog wrote: »

The fast charger in Kee's Petrol Station in Laghey (outside Donegal Town) has been out of service for weeks now, got caught twice going out there without checking first... :mad:

The North West is becoming a black spot. Take Letterkenny out and we're in real trouble. Glenshane has similar screen troubles to Derry too.

Batesy · 10-11-2017 11:13am

Anyone know the number to ring to get car wings reset? I’ve bought a 2nd hand Leaf and can’t register the VIN

gunnerfitzy · 10-11-2017 11:47am

Batesy wrote: »

Anyone know the number to ring to get car wings reset? I’ve bought a 2nd hand Leaf and can’t register the VIN

00 44 330 123 1231

Nissan Leaf

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