Leaf vs Ford Focus Electric

[Volusiano]

Doesn't this temp management on FFE work only if the car is plugged in? What happens when it's not?!

I'm pretty sure that it uses its own power from the battery pack to manage the temperature when it's not plugged in. Otherwise, what's the point if you're parked at work all day unplugged?

 

[nosuchthing]

At least that is the case with Tesla Model S...

 

[mkjayakumar]

We all know theoretically that a) absence of TMS hurts the battery in hot climates. b) TMS helps control degradation

a) has proven to be true by the Leaf design. On b) jury is still out.

It is possible that TMS that only runs when plugged in has very minimal effect. or maybe not. We don't know yet. Even if it runs when not plugged in, then you have to contend with a big hit in the range in summer months, because active cooling is consuming charge. So when you get back to your car after sitting in the lot for 8 hours you may very well be down by 15 miles in range. We don't know that..yet

In the end a BEV like Tesla Model S that have large batteries, any power consumption for cooling would be a small percentage of drain that all of this becomes meaningful, makes sense and doesn't impede in your daily use.

What lessons can we learn from Prius ?

 

[cwerdna]

We all know theoretically that a) absence of TMS hurts the battery in hot climates. b) TMS helps control degradation
...
What lessons can we learn from Prius ?

Non-plugin Priuses have no TMS other than a single battery fan. I think the PiP has more battery cooling fans, but I'm not sure. I'm pretty sure the PiP has no liquid cooling for the battery.

Regular Priuses can still function pretty well despite a large % of capacity loss.

Of the Priuses sold in the US, only the PiP has li-ion. The rest are NiMH based. The relatively new 7-seater Prius alpha (or +?) (aka Prius v wagon here) has a li-ion battery but the car's not available in the US.

We on Priuschat I believe have found correlation between early failure and high temps along w/hilly environments. I can't find the best post on this (probably by seilerts) but here are some decent/good ones:
http://priuschat.com/threads/2005-prius-241-000-miles-hybrid-battery-replacement-story.104985/page-2#post-1512179" onclick="window.open(this.href);return false;
http://priuschat.com/threads/2005-prius-241-000-miles-hybrid-battery-replacement-story.104985/#post-1497577" onclick="window.open(this.href);return false;
http://priuschat.com/threads/early-signs-of-potential-gen-2-prius-issues.98523/#post-1396372" onclick="window.open(this.href);return false;

On my Gen 2 Prius, per ScanGauge (not the MFD), Prius does not like it if SoC reaches 80%. If you get to almost 80% SoC while going down a hill, it'll turn the ICE on and have it rev high as a sort of engine braking and stops regening. It tries to (from memory) keep the HV battery at ~60% SoC. If it gets down to 40% or so, it wants to turn on the ICE to charge it back up or reduce your acceleration so that it can charge it.

There can also be problems if the battery fan gets clogged (http://lusciousgarage.com/blog/comments/prius_battery_cooling_fan_cleaning/" onclick="window.open(this.href);return false. There's even a TSB for the Gen 3 Prius about cleaning it, in certain cases. I won't really go there since there's no battery fan on the Leaf.

 

[planet4ever]

I know this is a Leaf forum so obviously there will be little support for the FFE, but has anyone mentioned that the FFE has a liquid heated/cooled battery pack?

And this is supposed to be news? It had already been pointed out twice on this very thread before your post, though perhaps you were not familiar with the acronym TMS which means exactly that. That term is defined in the MyNissanLeaf Wiki Glossary.

As to "little support", we have a 50 page thread here dedicated to the FFE. We're interested in a wide variety of EVs.

I think Nissan made a mistake going with a air heated/cooled battery pack. I hope that is remedied in the 2013 model.

"air heated/cooled" is not really accurate. AFAIK the only heating or cooling of the LEAF battery is by radiation. It has a sealed battery pack with no internal fan. And neither the 2011 or 2012 models have any cooling at all except when the ambient temperature is lower than the battery temperature. A heating coil was added very late in the 2011 model year, but its only purpose is to keep the battery from freezing in temperatures below 0°F.

I'm afraid your "hope" for the 2013 model is hopeless. It will not have a TMS.

The other factor is that Ford dealerships don't really have charging stations for customers like Nissan does.

I haven't checked widely, but that surprises me. There is only one public charging location in our moderately small city (a bit under 40K population), and that is at the Ford dealer. A salesman there told me it was available not only to FFE owners, but also to EV owners in general.

Ray

 

[bryan38401]

remember ford is just "testing the waters" beside the the leaf you will also have the infinite OMG it is one fine machine , I bought the leaf because if we learn from history the big three will do everything to see electric cars wont make it but I have my leaf!! wife wants the new infinite she likes it just as much as her leaf.I am waiting on my electric vans they also will be nissan e-nv200, and of course the ford electric transit is dead!!! already!

 

[Pipcecil]

Besides what has aready been mentioned the FFE has two things to think about:

The car is lower and smaller - therefore highway range is significantly better than the leaf. Having a leaf and a volt, the volt can almost match the range of the leaf on the highway with a significnatly smaller battery. If you do more highway driving this is something to consider, which is probably why the offical FFE range is slightly better.

The TMS, while protecting against heat allows for a more reliable range in various temperatures. Yes your car will always have less range in the winter, but because of the TMS, your range may only drop 5-10 miles in the FFE compared to the wild 10-20 miles in the leaf. The TMS allows for consistancey since it keeps the battery at the optimum performance temperature.

 

[mkjayakumar]

keeps the battery at the optimum performance temperature.

But then again, won't the charge get depleted just sitting in the hot asphalt to maintain the battery temperature ? What is the range hit for each hour the car sits in the 100+ weather ? in freezing temps ?

 

[RegGuheert]

The TMS, while protecting against heat allows for a more reliable range in various temperatures. Yes your car will always have less range in the winter, but because of the TMS, your range may only drop 5-10 miles in the FFE compared to the wild 10-20 miles in the leaf. The TMS allows for consistancey since it keeps the battery at the optimum performance temperature.

I am not convinced. TMS provides more reliable battery capacity, not necessarily more reliable range.

My observation is that the wintertime range hit comes largely because of the heater and has less to do with battery capacity. In other words, I believe I can drive our LEAF nearly as far in 30F weather as I can drive it in 90F weather, as long as I do not use the climate control in either case.

I will venture a guess that having to heat the battery in addition to heating the passenger compartment will completely negate any benefit obtained by maintaining the battery at warmer temperatures, at least in the climate here or where the OP lives in NJ.

I suspect the 2013 LEAF may have a longer cold-weather range than the FFE due to the new heat pump. It will be interesting to hear people's reviews of that particular feature.

 

[Stanton]

keeps the battery at the optimum performance temperature.

But then again, won't the charge get depleted just sitting in the hot asphalt to maintain the battery temperature ? What is the range hit for each hour the car sits in the 100+ weather ? in freezing temps ?

...and now you can begin to understand some of the cost/function trade-offs that Nissan had to make when designing the Leaf. TMS doesn't come for free: either literally ($$) or practically (range).

 

[Stanton]

When Ford has 35,000 of these FFE out in customer hands then we will find out if the car is any good or not. The TMS may help and it may not. At this time we really do not know.

Unfortunately, I wouldn't be surprised if we NEVER see the FFE achieve this sales milestone. Either because:
1) they're really not committed to BEV's or
2) they end up going with a "ground up" BEV re-design (which is essentially what Nissan did)

 

[x10guy]

And this is supposed to be news? It had already been pointed out twice on this very thread before your post, though perhaps you were not familiar with the acronym TMS which means exactly that. That term is defined in the MyNissanLeaf Wiki Glossary.

As to "little support", we have a 50 page thread here dedicated to the FFE. We're interested in a wide variety of EVs.

You are absolutely correct. In fact it was mentioned multiple times by others too. My apologies that was kind of dumb on my part. And what I meant by "support" was mainly related to this thread. I was just attempting to point out that most of the posts in this thread support the Leaf over the FFE which is obviously understandable since this is mainly a forum for Leaf owners. Most of them have valid reasons but the FFE does have some nice features too.

I do find it a bit interesting that in other threads how people bemoan the lack of TMS in the Leaf but in this thread it doesn't seem like a big deal on the FFE.

The other factor is that Ford dealerships don't really have charging stations for customers like Nissan does.

I haven't checked widely, but that surprises me. There is only one public charging location in our moderately small city (a bit under 40K population), and that is at the Ford dealer. A salesman there told me it was available not only to FFE owners, but also to EV owners in general.
Ray

The Ford dealership in my town said that their EV charging is only for the dealership and not for the public. I read somewhere that Nissan corporate pushed to have EV charging stations installed at the majority of their dealerships and to have them available for Leaf owners. But then again, I could be wrong once again.

 

[RegGuheert]

I do find it a bit interesting that in other threads how people bemoan the lack of TMS in the Leaf but in this thread it doesn't seem like a big deal on the FFE.

That's because the OP lives in NJ. As stated, I do not think battery TMS is an asset in cooler climates.

To put a finer point on the discussion of wintertime range, here is a recent quote from the Volt thread from a former LEAF owner in Seattle who now has a Volt:

Just passed 4k mark... Still loving the car despite 23-28 mile range in winter time.

So it seems the Volt loses about 1/3 of its range in early Seattle wintertime. I doubt the LEAF loses more than that in the same climate. (Of course this is not an entirely fair comparison since the Chevy Volt has access to only about 1/2 as much energy from the battery as the Nissan LEAF. As a result, the energy needed to heat the cabin is a larger percentage of the total available battery energy in the Volt. Still, the drop is significant.)

 

[mkjayakumar]

...and now you can begin to understand some of the cost/function trade-offs that Nissan had to make when designing the Leaf. TMS doesn't come for free: either literally ($$) or practically (range).

Understood. But do we have some real world data from FFE on this, yet ?

When the range cost to TMS becomes a small fraction of your total capacity then I think having TMS is a no-brainer as in the Model S. All these finer points becomes significant only on a small capacity battery like the Leaf & FFE. What about iMev ? Apparently that one has a TMS and how is it faring ?

Tesla did a smart thing of building a car from the higher end.

 

[x10guy]

I do find it a bit interesting that in other threads how people bemoan the lack of TMS in the Leaf but in this thread it doesn't seem like a big deal on the FFE.

That's because the OP lives in NJ. As stated, I do not think battery TMS is an asset in cooler climates.

To put a finer point on the discussion of wintertime range, here is a recent quote from the Volt thread from a former LEAF owner in Seattle who now has a Volt:

Just passed 4k mark... Still loving the car despite 23-28 mile range in winter time.

So it seems the Volt loses about 1/3 of its range in early Seattle wintertime. I doubt the LEAF loses more than that in the same climate. (Of course this is not an entirely fair comparison since the Chevy Volt has access to only about 1/2 as much energy from the battery as the Nissan LEAF. As a result, the energy needed to heat the cabin is a larger percentage of the total available battery energy in the Volt. Still, the drop is significant.)

Ooops. Sorry, I was under the impression that TMS also helped in cold weather too. I guess the moral of the story is that I should just keep my mouth silent before any more misinformation spews out... sigh.

 

[RegGuheert]

Sorry, I was under the impression that TMS also helped in cold weather too.

That claim has been made here many times, but I am questioning whether or not that is true.

Hopefully someone will eventually own both a 2013 LEAF and a 2013 FFE who can perform some head-to-head range tests in both hot and cold weather with and without climate control so that we can all learn more about this topic!

 

[klusters]

Well we've all experienced drops in battery performance in colder weather. I've noticed a diminished miles/kW average on colder days. My understanding, and please feel free to correct me, is the following:

The lithium ion battery has an ideal temp that it prefers for efficient charging and discharging. Any deviation from this even by a few degrees can seriously affect its performance. High temps decrease battery life by decreasing internal resistance and speeding up chemical degradation. Low temps affect both capacity and output by increasing internal resistance and lowering current output hence the lower miles/kW numbers and ineffecient charging.

The TMS on the FFE both heats and cools the battery as needed. It can run all the time, and bring the temp up or down to acheive both optimal charging environments and also driving environments.

Jimbo
2012 Leaf Blue Ocean
Delivered 10/12/12
1500 miles and counting

 

[RegGuheert]

I've noticed a diminished miles/kW average on colder days.

Me, too.

But I also notice that I can drive just about as far on each bar as I did in the heat of the summer if I do not turn on the heat.

When I have a chance, I will try do duplicate my 100-mile effort from June 2012, but at 30-degree temperatures instead of 80-degree temperatures. I may not quite make it, but I suspect I will be able to get close. It will be interesting to see how different the miles/kWh are compared with how different the actual miles are.

 

[LEAFfan]

Besides what has already been mentioned the FFE has two things to think about:


The car is lower and smaller - therefore highway range is significantly better than the leaf. Having a leaf and a volt, the volt can almost match the range of the leaf on the highway with a significantly smaller battery. /quote]

Almost match? Surely you jest. A new LEAF can go 84 miles at 65mph. And you really believe a Volt can almost match that? A Volt would be lucky to get 25 miles at that speed on its battery alone so that's not even close to almost.

 

[edatoakrun]

I've noticed a diminished miles/kW average on colder days.

Me, too.

But I also notice that I can drive just about as far on each bar as I did in the heat of the summer if I do not turn on the heat.

When I have a chance, I will try do duplicate my 100-mile effort from June 2012, but at 30-degree temperatures instead of 80-degree temperatures. I may not quite make it, but I suspect I will be able to get close. It will be interesting to see how different the miles/kWh are compared with how different the actual miles are.

Good luck!

You might want to review some of the cold weather threads from last year, where many tried to determine the cold temperature range effects, including this one, where I posted:

My Leaf Stats : Range vs Temperature

http://www.mynissanleaf.com/viewtopic.php?f=31&t=6701&start=60" onclick="window.open(this.href);return false;

On 11/8(11) I attempted to replicate the route and conditions of an earlier trip, which I had kept careful notes of, to try to see what sort of range reduction is caused by reduced m/kWh due to lower temperatures, and what proportion of this reduction is due to reduced battery capacity. I did this on a dry day with windows up, without using the heater or windshield wipers. I believe that I got about 5% reduction in battery capacity, and a slightly larger decrease in driving efficiency (m/kWh) resulting in a total range reduction of over 10%...

On 8/30(11) the overnight low was in the low 60’s, and the top off was done when the ambient temp had warmed to the mid 80’s , and my best estimate that the battery was probably in the 70’s at this time. The drive was done in temperatures of 80-95 degrees. I believe (but did not record) that the battery temp indicator remained at 6 bars for the entire trip.

The 11/8/(11) top-up charge was done when the overnight low was 35. I doubt that the battery temp was much higher than this. The temperature during the drive ranged from 47 to 36 degrees. Battery temp showed 4 bars until the recharge session, and it was at 5 bars for the rest of the trip.

So this approximately 40 degree decrease in temp when charging, and 50 degree reduction when driving, resulted in about 10% recorded range reduction...

I am less confident today of the effects of lower battery capacity than I was last year, as I am far less confident in the consistency and accuracy of my LEAFs m/kWh reports, but the overall range reduction of about 10% for that temperature reduction still seems about right, to me.