[Skibum]

So....what kind of range are people getting in Stealth mode? I'm a bit disappointed - i drove off this morning fully charged and had 5 short trips around town today. 4-6 miles each, total of 24 miles. When I pulled into my garage the range indicator was at 8 miles. If that was accurate that would suggest a total of 32 miles, and more likely that was overstating the case so total available range was under 30 miles.

What are you guys getting?

Skibum

 

[SoCalGuy]

I haven't had my battery fully charged (most I got was 19 mile of range since I didn't charge it all the way), but I will say that for the 19 miles of range, I probably got more like 12-13 miles. I think some of the juice was taken out when I popped into Sport mode and accelerated, so hard to say. I'm going to try to fully charge it this weekend and get some better data on range. I suspect it will be lower than the 50 (and maybe the 32) since where I live has many hills, so car will have to work harder to climb etc.

 

[ct-fiskerbuzz]

So....what kind of range are people getting in Stealth mode? I'm a bit disappointed - i drove off this morning fully charged and had 5 short trips around town today. 4-6 miles each, total of 24 miles. When I pulled into my garage the range indicator was at 8 miles. If that was accurate that would suggest a total of 32 miles, and more likely that was overstating the case so total available range was under 30 miles.

What are you guys getting?

Skibum

Do you always set it in Hill 1 or Hill 2 mode? I'd be interested in seeing people's experience in the relative effect of the hill modes.

Nissan Leaf drivers (who tend to report the most about these issues, probably because they are stuck if they run out of range and because there are more of those vehicles out than any other at this point) say terrain and temperature are the biggest variables for them. (Driving style also matters.)

 

[Skibum]

I'm in beautiful Northern CA, so temperature is not an issue. In fact,I should get a boost from the solar panel soaking up the sun in between trips! Ok, maybe not....

I'm almost always in Hill 1 or 2 mode.

I did show off on one of the trips - was with a friend who wanted to feel the 0-60 acceleration, so I did that a few times. Probably cost me a bunch of power.

 

[ct-fiskerbuzz]

I'm in beautiful Northern CA, so temperature is not an issue. In fact,I should get a boost from the solar panel soaking up the sun in between trips! Ok, maybe not....

I'm almost always in Hill 1 or 2 mode.

I did show off on one of the trips - was with a friend who wanted to feel the 0-60 acceleration, so I did that a few times. Probably cost me a bunch of power.

Probably.

As long as you're not in the flatlands (I guess that would require that you be in the central valley, or never out of the Livermore valley), you'll be going over the Berkeley hills or up Mt Tam or down Mt Diablo, etc., so using hill modes should help a lot, but you will still lose some energy via "battery friction" as it were. If flatland folks get 45 to 50 miles, you might expect 80 to 85% of that, or about 36 to 42.5 miles.

 

[brian]

I've found that it depends on the terrain, what speed you're going, and how well you use the regen brakes, and other power usage.

1. The battery drains VERY QUICKLY when going up even the slightest incline, and you don't get the equivalent energy back when you go down that incline. So, in hilly areas it drains about 2 to 3 miles of charge for every 1 mile of charge on the battery.

2. I've noticed that the battery drains disproportionally as speed increases, or so it seems. So, I get much better range if I do 45mph vs. 65mph. Because of this I actually avoid speeding because it just costs me precious range on the battery.

3. Using the regen braking as much as possible obviously makes a big difference. I try to almost never hit the brakes, but let the regen do all the work.

4. On the Tesla the A/C is about a 14% drain on the battery. Dunno if it's the same on the Karma, but it does cost a little. So far I haven't noticed much difference when using it tho.

So, on average, I'm getting around 41 miles on a charge (with the A/C off) and driving normally. If I avoid the highway and hilly areas I can get 45 miles or so.

-Brian

 

[ct-fiskerbuzz]

2. I've noticed that the battery drains disproportionally as speed increases, or so it seems.

Drag is (if all goes well) proportional to the square of the velocity, so doubling your average speed raises the power needed to sustain that speed by about a factor of four.

There is a range of (very low) speeds where drag is linear with speed, and there are turbulence regimes where drag is worse than vee-squared, so all these are quite approximate, but this is why hybrid vehicles generally get better city mileage than highway: 80 mph is four times worse for drag than 40 mph.

(The speed limit on I-15 here is 80, once you get out of the city areas, so I will no doubt be doing 80, if not more, anyway. )

 

[Skibum]

Thanks for all the info guys. For the record, I'm in Silicon Valley which is pretty flat. Use Hill 1 routinely to slow down, but I'm skeptical it's giving much back.

Will try again *without* showing off the engine and seeing how I do....

 

[dennis]

I have about 400 miles on my Karma, with about 70% around town and 30% freeway and always in Hill 2. I'm seeing 30-35 miles per charge.

I've been told that I drive aggressively, although it seems normal to me. As a calibration point, in similar driving I was getting about 12 mpg in my V10 BMW M5.

 

[Fnorrod]

I'm seeing about 35-40 miles per charge. It definitely depends on the terrain and your "aggressiveness." ;-)

One interesting thing I noted on the 6.10 firmware at least is that the miles remaining dropped rapidly for the first 4-5 miles of my daily commute: I was probably at 38 miles remaining after having driven 4 or 5 miles. After those first miles the mileage and "battery miles" started tracking more closely, I think there was still a 1.6:1 ratio or thereabouts, but not the 2.5:1 I saw starting out.

I finally got my new battery and the 6.11 firmware today. The somewhat terse release notes I received on 6.11 said that it did address a charge indication issue, so perhaps it will be different.

 

[Dutch]

I'm getting about 35 miles on a full charge when doing constant highway speeds of 70 mph (and a few miles of highway approach). But it's cold here, around 0 Celcius/32 Fahrenheit. I can see that the car is using about 35 kW when I'm doing 70 mph. I hardly ever have to brake on that 35 mile-part. I need 42 miles to get to my daily destination, so I hope warmer weather will give me some extra range.

 

[Michael]

42 miles, must be annoying, almost you could drive al the way to work.
Wonder how long the batteries will hold too before they loose power.

Hope better than an apple macbook which should last 6hours when new and now 3 years later 1hour

 

[Dutch]

The A123 batteries are the best in the market when it comes to keeping capacity over time. And if you get full charges and discharges, like I do, it helps prolong battery life. But if in 2-3 years time Fisker comes up with a replacement battery that offers 50% more range or so, I probably won't hesitate.

 

[Michael]

do you think this replacement batteries would fit the karmas they produce now? the double of range would be great

 

[kabalah70]

Dutch, everything I have read about batteries with LiFePO chemistry like A123, the greater the depth of discharge (DoD) the greater damage is done to the battery, due to the increased molecular strain. They do not create a memory like NiCd's do when recharging a bit at a time. Although not completly on the market, lithium titanate batteries have the best resistance to damage caused by DoD. Commercially, the Honda Fit EV is supposed to be the first to use them, sourced from Toshiba with their SCiB. After a quick review, it appears that the newest Mitsubishi iMiEV's have the Toshiba SCiB in them as well.

 

[matrix]

Does slow-charging using a Level-1 charger vs. faster charging using a Level-2 charger have any effect on long-term battery life?

 

[kabalah70]

Theoretically, yes, charging using a level-2 charger will increase the speed at which the battery will degrade, how much so, depends again, on the depth of discharge at each use, and other factors. Based on the 180kw that the battery can provide and that it is a 20kwh battery that means that it can support at least a 9C discharge, while the 220v EVSE is only recharging at about 1/3 C and 110v at like 1/10 C, it is the discharging that will probably be causing the damage to the battery and not the recharging.

 

[brian]

My understanding is that with these LiPO batteries the Level 2 charging doesn't really do any significant damage. It's the Level 3 chargers that fry batteries.

-Brian

 

[kabalah70]

brian, LiPo refers to Lithium Polymer batteries which are the ones that can run away due to the Solid Electrolyte Interface (SEI) breakdown. A123 is a new chemistry, Lithium Iron Phosphate (LiFePO). That being said Level 3 would be more damaging to either as the C rate is drastically increased. C rate being the divisor of 1 hour for recharge, i.e. 2C means a full charge in a 1/2 hour or 30 minutes, a 1/2 C charge would take 2 hours.

In order from worst to best resistance to structural damage due to discharge/recharge cycle (DOD = depth of discharge):

LiPo: http://en.wikipedia.org/wiki/Lithium_polymer
(500 cycles at 10C, 100% DOD) http://www.hardingenergy.com/index.php/lithiumpolymer

LiFePO: http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
(2000 cycles at 10C, 100% DOD)

Li2TiO3: http://en.wikipedia.org/wiki/Lithium-titanate_battery
(4000 cycles at 10C, 100% DOD)

 

[matrix]

brian, LiPo refers to Lithium Polymer batteries which are the ones that can run away due to the Solid Electrolyte Interface (SEI) breakdown. A123 is a new chemistry, Lithium Iron Phosphate (LiFePO). That being said Level 3 would be more damaging to either as the C rate is drastically increased. C rate being the divisor of 1 hour for recharge, i.e. 2C means a full charge in a 1/2 hour or 30 minutes, a 1/2 C charge would take 2 hours.

In order from worst to best resistance to structural damage due to discharge/recharge cycle (DOD = depth of discharge):

LiPo: http://en.wikipedia.org/wiki/Lithium_polymer
(500 cycles at 10C, 100% DOD) http://www.hardingenergy.com/index.php/lithiumpolymer

LiFePO: http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
(2000 cycles at 10C, 100% DOD)

Li2TiO3: http://en.wikipedia.org/wiki/Lithium-titanate_battery
(4000 cycles at 10C, 100% DOD)

Great info, thanks!