Can you "top off" after a DC quick charge without damage?

[Deleted member 1622]

Hello --
I'm planning a roadtrip to the country's first DC Level 3 quick charge station in Vacaville, CA to try it out.
http://www.wired.com/autopia/2010/05/our-journey-toward-public-ev-quick-charging-begins/
However, I'd like to put more than an 80% charge on the battery for the trip home to make sure I get all the way back. Does anyone know if plugging in a Level 2 right after a Level 3 is a bad move? The Level 3 charge will put me at 80% in 30 minutes, but also heat the battery much more than a Level 2. If I then immediately plug in to the Level 2 charger for another half hour or so for the extra juice, could it result in an overheat or long-term damage to the battery?
Any help would be appreciated.

Josh

 

[DarkStar]

Per the service manual, once it stops at 80% you can restart the DC Quick Charger to charge to 100%. Only if your battery is below 50% SOC will it stop at 80%.

 

[LEAFer]

For now ... do NOT plan this trip. The QC station is *not* confirmed as continously operating, pending (THAT :roll: word again) UL approval. (Don't kill the messenger.)

As to "filling" with J1772 after QC ... that should be possible. But Vacaville currently does not have J1772 as far as I know. But you could certainly stop by a Nissan dealer on the way home (?Fairfield, others?). Also see DarkStar's answer slipped in above mine.

(What direction are you coming from ?)

 

[ENIAC]

Hello --
I'm planning a roadtrip to the country's first DC Level 3 quick charge station in Vacaville, CA to try it out.
http://www.wired.com/autopia/2010/05/our-journey-toward-public-ev-quick-charging-begins/
However, I'd like to put more than an 80% charge on the battery for the trip home to make sure I get all the way back. Does anyone know if plugging in a Level 2 right after a Level 3 is a bad move? The Level 3 charge will put me at 80% in 30 minutes, but also heat the battery much more than a Level 2. If I then immediately plug in to the Level 2 charger for another half hour or so for the extra juice, could it result in an overheat or long-term damage to the battery?
Any help would be appreciated.

Josh

So you're planning a day drip to a EV charger? Okay, I would suggest you actually don't put much charge in your LEAF in Vacaville. That way you can go flat on your way home and make the news! :lol:

 

[GeekEV]

But Vacaville currently does not have J1772 as far as I know.

According to this, they do: http://electric.carstations.com/1539

 

[garygid]

Note that none of the "chargers" are verified as being operational or available to use at any given time.

 

[LEAFer]

But Vacaville currently does not have J1772 as far as I know.

According to this, they do: http://electric.carstations.com/1539

Ok ... but according to the following ... they don't; and my trust is (still) in the latter: http://www.evchargernews.com/regions/95687_6.htm

(Also ... there's no 14-50 there.)

Note that none of the "chargers" are verified as being operational or available to use at any given time.

True. But we've discussed this particular QC in another thread ... and there was already a report of it being NO-OP recently.

EDIT: To add the link to the "recent report": http://www.mynissanleaf.com/viewtopic.php?f=4&t=2927&start=16

 

[Ingineer]

There is no way to damage the pack in a Leaf using any kind of charge combination. The battery ECU's job is to protect the battery and it does. Even in the event of a DC charger gone crazy, it would still open the charge port contactor and halt charging.

-Phil

 

[Deleted member 1622]

Thanks for all the replies and info on quick charging. I'm coming from Berkeley, so it's not worth doing the trip until I have real confirmation on the phone that everything is up and running. The posts on that last thread talking about the charger are 9 months old now, I need some recent intel, so if there's anyone who lives in thAt area who can do a driveby, please let me know.
Yes, I am enough of an EV geek to get a thrill out of quickcharging, especially if I can be one of the first few dozen in the country to quick charge a Leaf. But for my wife, the thril is in the Vacaville outlet malls. I will do some research and report back when I successfully make the journey.
Josh

 

[garygid]

If you cannot "damage" the battery, even just a tiny bit, by any form of charging, then why does Nissan call 80% charging a "long life" mode and 100% charging is apparently NOT a "long life" mode?

Does 100% charging cause no "DAMAGE", but just cause greater "Wear and Tear"?

If so, will repeated QC to 100% cause increased "wear and tear", but no "damage"?

If DAMAGE is impossible, then we are clearly asking about increased levels of "wear", or decreased lifetime.

 

[Stunt822]

There is noting you can do to battery that would result in visible and immediate damage. However every case of battery working at high temperatures - will degrade it. Pushing more juice in hot pack - will have degradation effect. I wouldn't do it daily. But then even using batttery in normal way - adds some degradation. So don't panic.

 

[garygid]

Right, it is the hard-to-detect "wear" that we are trying to minimize, BEFORE it becomes a more-visible 15% reduction in battery capacity.

If the only advice is to use only from 80% down to 20% of the "usable" battery capacity, then we are starting with only 60 LA4 miles, maybe only 45 freeway (modest speed) miles.

Not a satisfactory solution for some users.

So, HOW MUCH is 100% charging, or QC charging costing us in terms of battery capacity loss?

 

[LEAFer]

Thanks for all the replies and info on quick charging. I'm coming from Berkeley, so it's not worth doing the trip until I have real confirmation on the phone that everything is up and running. The posts on that last thread talking about the charger are 9 months old now, I need some recent intel, so if there's anyone who lives in thAt area who can do a driveby, please let me know.
Yes, I am enough of an EV geek to get a thrill out of quickcharging, especially if I can be one of the first few dozen in the country to quick charge a Leaf. But for my wife, the thril is in the Vacaville outlet malls. I will do some research and report back when I successfully make the journey.
Josh

If by "The posts on that last thread" you mean the EVChargerNews ... the latest is 4 months ago (and anything unusual probably would have been reported: On 11/08 QC power was (apparently) OFF.). But the thread I hinted at: http://www.mynissanleaf.com/viewtopic.php?f=4&t=2927&start=16 has a report from 9 days ago of NO-OP. And ... George owes us some feedback

However, on Feb 18 George *did* use it successfully: http://www.mynissanleaf.com/viewtopic.php?f=27&t=2099&start=481

Anyway ... would be great if barsad22 could report about it operating ... otherwise someone more local or some other source will surely report in one of the two related threads when the QC station can be considered reliably available.

 

[Ingineer]

Technically as soon as the battery rolls off the assembly line it's already being "damaged", as they all have a certain amount of calendar life.

Accelerated wear != damage.

Think of tires, you can drive aggressively and wear your tires faster but this isn't called damage, it's called wear. If you hit a pothole and blow one out though, this is called damage.

Same thing with the pack. Fast charging all the time will wear it at a faster rate, but it will not damage it.

-Phil

 

[garygid]

As I said, our concern is "wear", and how to manage it well, not about "damage".

What visible indicators did Nissan provide to guide those who wish to be battery "wear-aware"?

Battery Capacity Meter: loses top "band" after about 12 to 15% loss.

Does a "Battery Health Check" at a Nissan dealer tell us anything useful?

 

[AndyH]

As I said, our concern is "wear", and how to manage it well, not about "damage".

Enough. Enough enough enough. Thank you Ingineer. Think tires. Wiper blades. Brakes, bearings, oil seals. The windshield wears! The electric window actuators wear. If it moves it wears. Battery's have very tiny moving things inside.

The pack has a cycle lifespan, and a calendar lifespan.

If we flat-bed the car from the dealer to our garage and not use it for 10 years, the pack will have reduced capacity. Calendar aging will likely balance out over time, though. Here's one year in storage for high-quality LiFePO4:

Moving to cycle life...

If we use 50% of the pack each day, at some point in the future the pack will have reduced capacity. IE: 2000 cycles is 4000 days.
If we use 100% of the pack each day, we might expect the future will be a bit shorter. IE 2000 cycles is 2000 days.
If we drive 400 miles each day and use L3/DC charge four times each day... IE 2000 cycles is 500 days.

If we normally use 50% of the pack (4000 days) but take a trip twice a year that uses two L3 charges enroute then we simply use a couple of those 4000 days in advance.

The M&M bag has a finite number of candies inside. We can eat them fast or eat them slowly. We can skip a couple of days and then eat four at a time. Eventually the bag will be empty.

To the original question - Yes you can quick charge to 100% with no more damage than L2 because the car will reduce the current as needed - it monitors battery temperature and will tell the charger when and how much to slow down.

Yes - it's true that if we overheat the battery and then fire-hose the charge energy back in we can destroy a pack. The good news is that the car simply will not let that happen. Ever.

Enjoy your drive!

 

[AndyH]

Do not use the door handles. Pulling the handle causes metal parts inside to rub on each other causing friction and wear. Eventually we'll need to replace the door levers. The strike pins wear as well - the nylon will wear and the metal pin will get a groove in it. If it weakens and breaks in a collision to the side, the door can open and our lunch can fall out.

It is much safer to always leave the windows down. Do not use the door handles - enter and exit through the open windows. It is much less expensive to replace the rubber strip on the top of the door than to have the dealer open the door to replace the latch mechanism.

There is no information on the CAN bus or the diagnostics port on the structural integrity of the inner door latches - it's a ticking time-bomb. There is no way to know in advance when it'll happen - one day we just cannot open the door.



[This is 100% true. My VW has 397,000 miles and I've replaced all four door handles once and the driver's side three times. But I certainly do not lose sleep over it or feel the need to beat it to death.]

 

[ENIAC]

It is much safer to always leave the windows down. Do not use the door handles - enter and exit through the open windows.

Thanks AndyH! I tried yer advice and now I feel like one of dim NASCAR drivers! My wife say I look more like Bo from Duke of Hazard when i jump in the LEAF now.

 

[AndyH]

It is much safer to always leave the windows down. Do not use the door handles - enter and exit through the open windows.

Thanks AndyH! I tried yer advice and now I feel like one of dim NASCAR drivers! My wife say I look more like Bo from Duke of Hazard when i jump in the LEAF now.

Wait until you experience the extra freedom of movement from the short-shorts! Just make sure the driver and front passenger don't dive head-first into the car at the same time. :lol:

 

[palmermd]

Moving to cycle life...

If we use 50% of the pack each day, at some point in the future the pack will have reduced capacity. IE: 2000 cycles is 4000 days.
If we use 100% of the pack each day, we might expect the future will be a bit shorter. IE 2000 cycles is 2000 days.
If we drive 400 miles each day and use L3/DC charge four times each day... IE 2000 cycles is 500 days.

If we normally use 50% of the pack (4000 days) but take a trip twice a year that uses two L3 charges enroute then we simply use a couple of those 4000 days in advance.

The M&M bag has a finite number of candies inside. We can eat them fast or eat them slowly. We can skip a couple of days and then eat four at a time. Eventually the bag will be empty.

To the original question - Yes you can quick charge to 100% with no more damage than L2 because the car will reduce the current as needed - it monitors battery temperature and will tell the charger when and how much to slow down.

Yes - it's true that if we overheat the battery and then fire-hose the charge energy back in we can destroy a pack. The good news is that the car simply will not let that happen. Ever.

Enjoy your drive!

Finally somebody said it. Thank you.