Yesterday I loss my 3rd bar @ 26 k miles..

[brettcgb]

I've never really understood how a Leaf battery pack is useful for utility companies as a method of maintaining supply. Wouldn't the entire 20k list of current USA Leaf's be insufficient for this task?

At some point, the battery pack capacity has been reduced so much that normal day-to-day use in no longer practical as a traction battery (around 70-80% of the original capacity). Replace the pack to restore traction use.

What to do with the old pack? As a stationary pack, it could be quite useful as a means of shifting electrical load throughout the day, or leveling power generation capabilities for solar or wind sources. These uses still need to be developed.

About the time vehicle packs begin to be routinely replaced, I'd bet someone is going to offer a kit for the interested home owner to install the old battery in the garage as a load shifting device.

 

[LEAFfan]

[LEAF] Before Its sale, it was making about 65 miles
[Volt] With my volt, I drive about 50-55 miles without a gas

...I finally came to a conclusion that I have made a mistake when I purchased the leaf
...I have driven it about 5300 miles and never needed a drop of gas.

In the end it comes down to personal preference, and it appears you just like the Volt better. Maybe the seats are bigger or the visibility better or something. From the above things seem about equal. You can drive 55 miles in a volt or 65 miles in a LEAF so there's no clear advantage there. You don't use the engine so I'm not sure what having one gets you. If I bought a car that had an engine I never used, I would be thinking I had made the mistake.

LOL, 65 miles in a LEAF? You figuring 75 mph? Because there's no way the OP is going to get 50-55 miles at 75mph. If the OP got 50 miles driving slower speeds, then the LEAF can go over 100 miles easily. I just drove 188 miles on ONE charge. So before you say 65 miles, please quantify.

 

[GRA]

I'm not even a green person, but the prospect of self-sufficiency by having my own solar/wind feeding into a battery bank with utility power serving only as an auxiliary source is extremely appealing to me for some odd and unexplainable reason. Think about it- why exactly should we be so reliant upon centralized power generation when we have other options available to us.

I can't wait for someone to get their hands on a few old cells just to create a proof of concept. I think decentralization will be the trend going forward.

Why wait? I was designing and selling off-grid systems two decades ago, and prices are far better now than they were then. To get you started, this has been the go-to source for off-grid people for 25 years now:

http://www.homepower.com/" onclick="window.open(this.href);return false;

Re using Li-ion specifically for off-grid RE systems, see this article:

http://www.homepower.com/articles/solar-electricity/equipment-products/lithium-ion-batteries-grid-systems" onclick="window.open(this.href);return false;

 

[brettcgb]

So in the cold weather I should either park the car in the garage (mine is heated) or use the trickle charger?

I assume by "use the trickle charger" you mean park outside and trickle charge instead of parking in the garage and using L2.

So it depends - do you want to maximize battery life or maximize cold weather range? Unless you heat your battery to over 75F, I'd just do whatever is most convenient in the winter and don't worry about it.

But if you want to maximize battery life you'd park wherever it's cooler (probably outside). But if you want to maximize winter range (cold batteries hold less energy), park the car in the garage.

Starting with model year 2012, all battery packs have heaters that will keep them from getting too cold for use (heater turns on at -4F, off at 14F, see page EV-5 in 2012 user manual). Plug into the L2 at home, charge normally (the charger adapts to temperature), and use the climate timer to warm up the cabin before leaving for the day.

 

[TimLee]

I sold it when it was 15,000 miles and I purchase 2012 Chevy Volt. ...
I have driven it about 5300 miles and never needed a drop of gas.
...

My only reason is the battery of leaf and Nissan's approach on warranty issues. I just did not want to be told by Nissan as the origin of this thread: "go lose another bar and we will fix it"

My response is "fix it now, if you can"

You may not have put any gas in the Volt yet, but you have used some gas as the ICE will start occasionally for reliability reasons.
If you use the ICE very infrequently, you should leave the gasoline tank very low, to be sure that you use the gasoline up and replenish, rather than leaving it with very stale gasoline. Very bad for gumming up fuel injectors.

I'm glad the Volt is working well for you. It may be a better choice for you than LEAF.
But Nissan never guaranteed battery capacity when they first sold the LEAF, and we all knew it would lose capacity.
We just weren't well informed as to how soon.
So to be critical of Nissan "go lose another bar and we will fix it" approach, seems hyper critical.
I think most of us think Nissan should make their newly offered capacity warranty 80%, 5 years, 60,000 miles instead of 70%.
But to think they were going to fix capacity with only one (or two bars) lost is completely unrealistic.

 

[DaveEV]

If you bought the car and didn't lease, you want the battery to last as many years as possible (i.e., well over ten years and maybe 15 or 20), and your garage is heated, then I'd advise parking outside at night even during the cooler months. The exceptions would be occasions when you need maximum range or whenever you're expecting snow and don't want to have to clear off the car. TonyWilliams and others have estimated a 1% temporary drop in battery capacity for every four degrees below 70 Fahrenheit, so most of your range loss in the cold will probably come from using the heater.

For sure, that is great advice.

Also, particularly during the warmer months, try charging to only 50% or so if that's enough to fully meet your daily range needs. Low SOC (but not super low) has a protective effect in heat.

I really wish Nissan had end-charge SOC adjustable like Tesla does in their latest firmware - completely adjustable from 50%-100%. I typically use about 30% SOC each day, so ideally like to charge to 65-70%. I notice that even at 75-80% regen is limited compared to lower SOC especially in cooler weather and having the battery spend most of it's time at a 15% lower SOC would be beneficial.

Right now the only way I can do it and stay in my super-off-peak rates is to tweak the start/end timer manually each day according to how much range I've used - not exactly user-friendly.

Somebody please explain to me why the over ten year old Toyota RAV4 Electrics owned by SCE are still getting over 100 miles in range and why two year old Leafs are losing range far below the nominal 70.

That seems to be a bit optimistic. Anyway, the NiMH batteries have slightly more capacity (27 kWh) which gives the old RAV4-EVs a bit of a head start as long as you keep freeway speeds low. NiMH batteries do have one advantage over lithium, is that as along as they are maintained well, they don't suffer much from age-based capacity loss - meaning they don't degrade very fast at all just sitting there unless you really store them hot (meaning over 35C). That said, many of the RAV4-EVs had significant battery issues over time - you really were lucky if yours made it to 10 years on the original battery pack. The NiMH batteries also had half the energy density compared to the LEAF's Lithium batteries - the same pack in the LEAF would weigh twice as much and who knows where you'd put all the cells...

 

[sparky]

I would rather make a claim for replacement as soon as it happens because it might happen again at 59,700 miles and then I'll get new packs twice.

It almost seems like we are all going to lose 4 bars at 30K miles, if that's true we may be back at 40K, 50K, and 60K.

In New Jersey? I doubt it! Your pack should hold up relatively well and likely won't lose nearly enough capacity for the warranty to kick in.

Personally, I highly doubt that I'll be utilizing the capacity warranty. My LEAF has almost 35K miles and all twelve capacity bars thanks to our cool mountain air.

I think your notion about average pack temp may be the key issue abasile. I'm not in an especially cool part of SoCal (Glendale). My LEAF is about 29 mos old with about 25k miles. Recent 'Gid readings from a 100% charge are about 260-270. I see that many others in SoCal show significantly lower capacity. My LEAF is parked outside, in the shade. It spends the workdays in a parking structure that has open-air cooling. I very rarely see 6-bars and have seen 7-bars only a handful of times. This cooler operation in a warm (not Phoenix-hot) climate may be the key to it's seemingly longer life. This would seem to confirm that tbleakne's got the right approach in keeping his LEAF in an actively cooled garage.

 

[surfingslovak]

I think your notion about average pack temp may be the key issue abasile. I'm not in an especially cool part of SoCal (Glendale). My LEAF is about 29 mos old with about 25k miles. Recent 'Gid readings from a 100% charge are about 260-270. I see that many others in SoCal show significantly lower capacity. My LEAF is parked outside, in the shade. It spends the workdays in a parking structure that has open-air cooling. I very rarely see 6-bars and have seen 7-bars only a handful of times. This cooler operation in a warm (not Phoenix-hot) climate may be the key to it's seemingly longer life. This would seem to confirm that tbleakne's got the right approach in keeping his LEAF in an actively cooled garage.

That's a great data point! I would be curious to know what your long-term energy economy might be. Some believe that gentle driving habits could help extend the life of the pack. I'm sorry if I missed this, but are you in the 80% club?

 

[sparky]

That's a great data point! I would be curious to know what your long-term energy economy might be. Some believe that gentle driving habits could help extend the life of the pack. I'm sorry if I missed this, but are you in the 80% club?

Yes. Except weekends are usually 100%.
Energy economy is pitiful. My wife drives the LEAF like a slot car.... ~3.3 mi/kWh (I was not much better).
Just after the LEAF turned 2, I did a 100 mi test. Based on other reports, I knew I had the battery capacity but I failed the first time because I just didn't know how to drive to get over 5 mi/kWh on fairly flat terrain. Second try was a success (103 mi, 5.8 mi/kWh) but it took all I had to stay off the pedals.

I know that loss of the 1st bar is coming, but it appears I'll get through another summer if the LEAF stays relatively cool those months.

p.s. I've never gotten "all 5 stars" at the annual battery checkup.

 

[abasile]

I really wish Nissan had end-charge SOC adjustable like Tesla does in their latest firmware - completely adjustable from 50%-100%. I typically use about 30% SOC each day, so ideally like to charge to 65-70%.

Ditto here! I hope Nissan is paying close attention to Tesla! Right now my LEAF is at 71.1%. I wanted more like 67-68% for my drive down the mountain, but didn't unplug it in time. It's like a crap shoot trying to manually time the charge...

 

[mark1313]

Well I loss another 5 miles after a fresh charge ...Something tells me Ill be lucky to make it through June with out losing the 4th bar ...

 

[supra410]

Forgive me for sounding dumb, but with the cap loss. Does the car get full faster?

 

[DaveinOlyWA]

Forgive me for sounding dumb, but with the cap loss. Does the car get full faster?

probably but only slightly quicker. the fastest charge happens at a low state of charge. As it fills up the rate of charge slows down. unfortunately, most of the time to charge is the slow part near the top of the pack and ALL of the loss is at the top as well. a smaller capacity only means the rate of charge slows down sooner.

**edit** this is reference to fast charging only since L2 ramp down of the charge rate is a very short window

 

[GerryAZ]

Forgive me for sounding dumb, but with the cap loss. Does the car get full faster?

probably but only slightly quicker. the fastest charge happens at a low state of charge. As it fills up the rate of charge slows down. unfortunately, most of the time to charge is the slow part near the top of the pack and ALL of the loss is at the top as well. a smaller capacity only means the rate of charge slows down sooner

I have only lost 2 bars so far, but L1 and L2 charging times from dead to 100% are certainly reduced. L2 charging rate is essentially constant (tapering off only during the last few minutes) so the charging time from dead is reduced by about 20% if capacity is down 20%. Since L3 (DC quick charging) tapers rapidly as state of charge increases (especially above 80%), the difference in charging time for L3 is minimal.

Gerry

 

[LEAFfan]

When my '11 was down 20%, it only took about 17 mins. to QC when it used to take 27-28 mins.

 

[QueenBee]

Forgive me for sounding dumb, but with the cap loss. Does the car get full faster?

probably but only slightly quicker. the fastest charge happens at a low state of charge. As it fills up the rate of charge slows down. unfortunately, most of the time to charge is the slow part near the top of the pack and ALL of the loss is at the top as well. a smaller capacity only means the rate of charge slows down sooner

Dave, could you reference a charging curve that supports that "most of the time to charge is the slow part near the top"? Maybe you meant to refer to only DCQC and not level 1/2 charging? I think your guess that it's only slightly quicker is not accurate for both level 1/2 and DCQC.

Also, it's not clear what you mean by "ALL of the loss is at the top". All of what loss? The car's capacity will certainly be lost with time and use even if you never charge past 80% and there are certainly charging efficiency losses at any charging SOC.

 

[DaveinOlyWA]

When my '11 was down 20%, it only took about 17 mins. to QC when it used to take 27-28 mins.

that does not compute. so no matter where the "top" or full is, the charger only gauges what is in the battery at the bottom when charging? so if a DCFC runs at full speed up to 50% SOC and you are charging a battery that is 50% degraded, then it will charge at full speed until complete?

 

[DaveinOlyWA]

probably but only slightly quicker. the fastest charge happens at a low state of charge. As it fills up the rate of charge slows down. unfortunately, most of the time to charge is the slow part near the top of the pack and ALL of the loss is at the top as well. a smaller capacity only means the rate of charge slows down sooner

Dave, could you reference a charging curve that supports that "most of the time to charge is the slow part near the top"? Maybe you meant to refer to only DCQC and not level 1/2 charging? I think your guess that it's only slightly quicker is not accurate for both level 1/2 and DCQC.

Also, it's not clear what you mean by "ALL of the loss is at the top". All of what loss? The car's capacity will certainly be lost with time and use even if you never charge past 80% and there are certainly charging efficiency losses at any charging SOC.

When my '11 was down 20%, it only took about 17 mins. to QC when it used to take 27-28 mins.

sorry, my statement is for fast charging. as far as loss at the top. it is capacity I am referring to. but LEAFfan made a statement that implies that the station may only determine its charging speed based on voltage which would not indicate any measure of capacity loss. this could eventually lead to a situation where fast charging will significantly speed up degradation because the charge rate is not slowing down quickly enough. granted that level of degradation would be severe but since there is only a general guideline as to when a battery "should" be replaced, those who choose to replace a battery at 50% degradation could see a fast charge that runs at full speed almost to completion?

 

[TomT]

My L1 and L2 charging times are now about 20% less than when the car was new...

Forgive me for sounding dumb, but with the cap loss. Does the car get full faster?

 

[TomT]

The car communicates the charging information to the QC so, theoretically, this should be taken in to account if the car's BMS is doing its job...

sorry, my statement is for fast charging. as far as loss at the top. it is capacity I am referring to. but LEAFfan made a statement that implies that the station may only determine its charging speed based on voltage which would not indicate any measure of capacity loss. this could eventually lead to a situation where fast charging will significantly speed up degradation because the charge rate is not slowing down quickly enough. granted that level of degradation would be severe but since there is only a general guideline as to when a battery "should" be replaced, those who choose to replace a battery at 50% degradation could see a fast charge that runs at full speed almost to completion?