Inaccurate facts and faulty reasoning. The Volt works fine in "battery mode" for many people. Just as with TMS, it depends on how you need to use the car. The only reason I don't consider the Volt is the cabin design.
Battery temp management for new leaf
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Inaccurate facts and faulty reasoning. The Volt works fine in "battery mode" for many people. Just as with TMS, it depends on how you need to use the car. The only reason I don't consider the Volt is the cabin design.
Durandal
Well-known member
Your car only takes a range hit from when you use the air conditioning. Any range hit from simply HAVING the air conditioning is negligible... As such, those in temperate environments will only have their battery ATM turn on when quick charging and in really hot summers. Is that such a problem? How about I whine and complain that my Leaf has a battery heater when I never need it for my hot climate? No, I don't, because it doesn't bother me, because it doesn't turn on. It makes sense for people to be upset at the Leaf NOT having battery ATM when their batteries crap out early, but it makes absolutely NO sense for people in temperate climates to complain about the idea of the Leaf having battery ATM.
Durandal said:
The problem, though, is that a BEV's battery has a high thermal mass basically requiring the ATM system
to always be active, i.e. a BEV's battery has a very long thermal time constant which would require increasingly
more battery power the narrower the desired temperature band. It's not like pushing the AC button and having
the interior cool within minutes.
Durandal
Well-known member
You're not trying to keep the battery from hitting 80F, you're trying to keep it from hitting 100F+ while charging or discharging. In winter times, the battery won't see those temperatures, and the damage is more done when charging/discharging at high temperatures. So if it activates as soon as you start doing a DC fast charge, it can prevent the temperatures from hitting those damaging levels while doing a bunch of nothing when you're driving around in town.lorenfb said:
In any event, I'd rather have an intermittent energy penalty of 300w-500w continuous and have a traction battery that gets an extra year or two of longevity than to save that 300w-500w of usage and have a vehicle that is less than practical after 7 years time.
Durandal said:
That's your guess on the power 'hit'! Do have a design for a proposed system that Nissan can use?
If one uses your worst case number (500W) and 24 hr 'on' time in some climates, that's about 12 kWh of energy per day.
Obviously, a good portion of that energy would be supplied when connected for charging.
Durandal
Well-known member
Do you have some snark that Nissan can use? If you read my bloody original message, I suggested ATM that would only be used when discharging or charging the battery, which is when more of the heat damage would be done versus when it's sitting idle. It's ridiculous to suggest that such a system would run 24 hours a day.lorenfb said:
Durandal
Well-known member
Here's some reading material for you. Enjoy.
http://publications.lib.chalmers.se/records/fulltext/200046/200046.pdf
http://publications.lib.chalmers.se/records/fulltext/200046/200046.pdf
Durandal said:
Nice article, thanks
I've wondered for a while now how much energy per time is released into the battery during use and charging. This data is helpful:
So even during moderate acceleration there is 2 kW of heat to remove.
DC charging is going to be multiples of that amount
edatoakrun
Well-known member
No, it's not, and neither was the Gen one Volt, as used by most of its drivers.rmay635703 said:
The primary message from that link you supplied is what an extremely poor PHEV design the gen one Volt was.
All the extra cost and complexity, all the compromises in interior and room and drivabilty, all the kWh drained from the grid, that Volt still got only ~59 miles of range from each gallon of the ~6,750 gallons gas it used, while emitting ~90,000,000 gallons of C02 just from the tailpipe.
God-only-knows how many more millions of gallons of CO2 this monstrosity produced in the production process, and in generation of electricity so inefficiently used during the ~35% of the miles driven when it was not fueled by gas.
What the Volt gen one proved is that batteries carried in a refrigerated case and acting primarily as deadweight, rather than supplying propulsion energy, will indeed last a very long time.
SO WHAT?
My LEAF, nearing the end of it's seventh (and hottest yet) baking North-Sacramento-Valley Summer, and after ~56 k gas-free miles, traveled 104.2 miles Tuesday on a single charge without even reaching the VLBW.
And also (possibly) nearing the end of my LEAF pack's first life, it still has over 50% more electric range under all conditions than any Gen one Volt did on the day of delivery.
finman100
Well-known member
yay! one data point!
Durandal said:
Yes, just having a cooling process active during charging would be beneficial, but that would be secondary to reducing
the effects from ambient temperature extremes for some. Besides, once you introduce a battery cooling system,
the battery then needs to be insulated from the vehicle's chassis, which then reduces the chassis' effect as a heat sink
necessitating on-going cooling - more power consumption.
- Anecdotal -
During L3 charging for about 15 minutes, my battery temp changes about 2-4 deg C, whereas driving here in SoCal
for about four hours results in an increase in battery temp about 10 deg C during the summer.
rmay635703
Well-known member
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edatoakrun said:
You do understand the 400,000 mile Volt was going 85-90mph basically the whole time?
I know Prius drivers who do that and are in the low 30's mpg
Although you or I may disagree with how fast he drives and how far he drove we can't draw the conclusion that he used more energy than any other alternative cars driving a Volt 90mph nor would a leaf have even made the commute he drove day in and day out driving that way.
Think before you speak
edatoakrun
Well-known member
Off-topic reply:
Post your own Volt efficiency results then.
But first please read the Gen one Volt thread, where the Volt's poor economics and efficiency have already been discussed thoroughly, and post there if you have a further comment.
http://www.mynissanleaf.com/viewtopic.php?f=10&t=713&start=2390
But first, please do explain how this Volt gets ~35% of its miles from the Volts tiny restricted battery capacity, "going 85-90mph basically the whole time".
Sounds like it must be stopping after every 40 or 45 minutes of "85-90mph" driving, and then waiting for a ~3 hour recharge.
That's one hell of a strange way to drive ~40k miles a year...
YOU post the link, then YOU complain it is not representative? of Chevy Volt'srmay635703 said:
Post your own Volt efficiency results then.
But first please read the Gen one Volt thread, where the Volt's poor economics and efficiency have already been discussed thoroughly, and post there if you have a further comment.
http://www.mynissanleaf.com/viewtopic.php?f=10&t=713&start=2390
But first, please do explain how this Volt gets ~35% of its miles from the Volts tiny restricted battery capacity, "going 85-90mph basically the whole time".
Sounds like it must be stopping after every 40 or 45 minutes of "85-90mph" driving, and then waiting for a ~3 hour recharge.
That's one hell of a strange way to drive ~40k miles a year...
https://www.voltstats.net/Stats/Details/1579
edatoakrun
Well-known member
Is insulation of ATM EV battery packs is largely mythical?lorenfb said:
Does any BEV manufacturer actually insulate their BEV packs, after the disastrous results shown by the early (insulated pack?) Ford focus E's in AVTA testing?
Seems like insulation is far more of a problem than a solution, except For BEVs cold climates where heat loss is a major concern.
For pack cooling, the cost (in energy consumption, reduced range, reduced battery life?) from the increased energy use/battery cycling required to cool an insulated pack, will be likely tend to exceed the cost of damage (in battery life) from the heat gain from ambient sources in an un-insulated pack.
Now, when some bright engineer develops the first practical actively insulated battery pack, the discussion will change...
rmay635703
Well-known member
- Joined
- Jan 19, 2011
- Messages
- 628
edatoakrun said:
I do not envy him for certain.
He does charge 3+ times a day and his jobs demands did border on insane, his EV % is slowly moving up because he moved.
As for me
powersurge
Well-known member
I can see that so many conversations about the Leaf, and its limitations turn into "Leaf-bashing", or "Nissan designer-bashing". It is almost like we are talking about the Trump-Hillary debate. No matter how well the Leaf has performed as the first mainstream, low cost EV, it is still getting bashed as inadequate.
Before the Leaf, the best you could do for an electric car was the CITICAR, which could take you a full 15 miles. The Leaf is to gas cars like the Ford Model T car... No matter how bad it was, it was light years ahead of the horse....
Check out the Citicar:
https://www.youtube.com/watch?v=sVcXgzWEODc
I have a Leaf in NY, and have absolutely no problems with it, or with battery temperature. If you are in hot climates, then don't buy a Leaf and wait until they have resolved the climate problem. That would also motivate car companies to make cars that can run in tropical climates. Currently, people in HOT areas are unrealistically demanding that the car "SHOULD WORK IN HOT CLIMATES", and having a Leaf there is like forcing to have a horse pull a freight train. It will kill the car.
Before the Leaf, the best you could do for an electric car was the CITICAR, which could take you a full 15 miles. The Leaf is to gas cars like the Ford Model T car... No matter how bad it was, it was light years ahead of the horse....
Check out the Citicar:
https://www.youtube.com/watch?v=sVcXgzWEODc
I have a Leaf in NY, and have absolutely no problems with it, or with battery temperature. If you are in hot climates, then don't buy a Leaf and wait until they have resolved the climate problem. That would also motivate car companies to make cars that can run in tropical climates. Currently, people in HOT areas are unrealistically demanding that the car "SHOULD WORK IN HOT CLIMATES", and having a Leaf there is like forcing to have a horse pull a freight train. It will kill the car.
EV-1, Zen Car, Solectria (?) GEM, and, of course, one-off conversions. The Citicar was the Model T, but there were many others before the Leaf.
GetOffYourGas
Well-known member
LeftieBiker said:
Yes, but none of those were mass-produced highway-capable cars that you could buy and own. The Leaf was really the first. And to date, it is still the best-selling EV ever built.
I agree with powersurge. In general, people are too quick to bash the Leaf because it isn't everything they need it to be. But in reality, that's asking too much and Nissan did a stellar job of bringing a truly affordable EV to market. No one has matched that yet. The Bolt and Model 3 aren't the same level of affordable.
BTW, there were gas cars before the Model T. But it was the Model T that was the real break-out car.
