Fisker Buzz Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
80 Posts
Discussion Starter · #1 ·
Coincidence?

I have a almost exactly 15 mile commute - i typically plug my car in overnight and start off with 50 miles of range - I usually end my commute with anywhere 30 - 32 miles of range left - implying my 15 mile commute cost me between 20 and 18 miles of battery range - which is acceptable for me.
I plugged my car in friday evening and it stayed plugged in until this morning - 2 1/2 days, when I got in I noticed that it took the car longer to reduce to 49 from 50, but I ended my commute with 39 miles of range - so my 15 mile commute cost me 11 miles of HV range - there was nothing different about my commute, route or temperature (I live in San Diego) - and I doubt i continuously get this milage.
I have owned the car for about three months.

But my question is : is there some benefit to occasionally leaving your car plugged in for 2 or 3 days?
 

·
EX:Shadow/Canyon #324
Joined
·
1,217 Posts
My Karma started acting like that just before the HV battery failed. So keep an eye on it and if you're charging time extends and your range appears to increase you may have an impending problem.
 

·
Registered
Joined
·
334 Posts
My Karma started acting like that just before the HV battery failed. So keep an eye on it and if you're charging time extends and your range appears to increase you may have an impending problem.
did you r car reached the 50 mile (full charge ) for more than 5 hours on level2?
 

·
EX:Shadow/Canyon #324
Joined
·
1,217 Posts
did you r car reached the 50 mile (full charge ) for more than 5 hours on level2?
My charging times were normally 5.5 hours to go to full charge from an empty battery. They gradually extended out to almost 7 hours, and then one day went to 10 hours. On that particular charge it indicated 50 miles battery range for the first 8 miles of travel. Then it started to decrease normally. That's when I took it to the dealer and they verified a problem with the HV battery and replaced it.
 

·
Registered
Joined
·
80 Posts
Discussion Starter · #5 ·
on a level 2 charger - i charge up in about 5 hours form empty. on a level 1 it takes about 12 hours from empty. I know my battery was new.

I guess I was asking some of the battery experts if there is anything to "rebalancing" the battery.
 

·
Registered
Joined
·
334 Posts
on a level 2 charger - i charge up in about 5 hours form empty. on a level 1 it takes about 12 hours from empty. I know my battery was new.

I guess I was asking some of the battery experts if there is anything to "rebalancing" the battery.
i dont think there is any thing wrong with your battery , these numbers are normal. its very intersting that u geting more miles if you left it for 2 days on the charger , i always though the charger shut off when battery full and wont start again .. but look like its keep tapping off ..
 

·
Registered
Joined
·
80 Posts
Discussion Starter · #8 ·
Not really. I average between 33-42 miles some days for whatever reason i get better,.BTW I live In SoCal.
 

·
Registered
Joined
·
1,171 Posts
The best mileage I've ever gotten was 47 miles on a single charge. This was under ideal conditions though. Cruise control set at 67mph, straight down the 5 freeway towards San Diego. No traffic, never touched the brake or gas.

Average is usually 35-45 miles or so.
 

·
Premium Member
Joined
·
3,063 Posts
asulil - Are you still getting good miles on your charge by keeping the car on charger for extended period of time ?
You won't gain anymore mileage keeping the charger connected any longer once it's charged it charged the charger stops when fully charged at 50 miles unless your battery has a replaced module or a defective module keeping it on an extended charge will help balance out the modules
 

·
Registered
Joined
·
25 Posts
You won't gain anymore mileage keeping the charger connected any longer once it's charged it charged the charger stops when fully charged at 50 miles unless your battery has a replaced module or a defective module keeping it on an extended charge will help balance out the modules
Harleyguy, this is not what my dealer says. They say that charging for 48 hours does make a difference. If I remember well because the software starts recharging/charging cells. Several problems can be solved by letting the car charge for more than 48 hours.
 

·
Registered
Joined
·
1,171 Posts
Who's your dealer? Harleyguy is right. All it does is re-balance the cells. Once a battery is full, it's full. Leaving it connected longer doesn't make it anymore full.
 

·
Registered
Joined
·
25 Posts
Who's your dealer? Harleyguy is right. All it does is re-balance the cells. Once a battery is full, it's full. Leaving it connected longer doesn't make it anymore full.
Kroymans in The Netherlands
 

·
Registered
Joined
·
80 Posts
Discussion Starter · #14 ·
Who's your dealer? Harleyguy is right. All it does is re-balance the cells. Once a battery is full, it's full. Leaving it connected longer doesn't make it anymore full.
Can some one ELIA5 (explain like I am 5) - what does rebalancing the cells actually mean?

1 If you have a bad cell - will it get worse? Cause other problems.

For instance when ever I get to 3 miles left in the battery (but not before) the 3 miles last about 3 seconds! CEL comes on (sometimes). But I am averaging the same mileage as everyone else between 33-43, and a few times my best was between 45-48, so it isn't impacting the car accept the annoyance of the occasional CEL.

I figure at some point I will have to replace the battery, but while it's working why mess with it - maybe in a few years there will be options for better batteries.
 

·
Registered
Joined
·
199 Posts
@DKV I have the same dealer....They told me to charge it for 48 hours once in a while to re-balance cells. Starting with an empty HV battery.
I guess you misunderstood. But then I am an engineer LOL
 

·
Cloud Based App Developer
Joined
·
91 Posts

·
Registered
Joined
·
913 Posts
With the Fisker-supplied 120 volt charger I was getting charging rates that worked out to 13-ish hours for a full charge (never did a full charge, so this is all approximate). These chargers will in general slow down if they detect slightly-low-voltage on the outlet you have them plugged-in-to. A 30% slowdown (the 17-18-ish hour charge, vs ~13 hours) could mean that your voltage is low at the outlet, or you have something else on the same circuit (this will drag down the voltage while the "something else" is pulling current).

Or, it could be a battery issue. There's no way to tell without testing. If you have a voltmeter or power quality monitor, you could use that to see if the "120 volt" outlet really is the correct voltage (was 117 VAC RMS plus or minus about 5 percent, apparently it's been tweaked some and varies from US state to US state now).

http://en.allexperts.com/q/Electrical-Engineering-1356/2008/2/Line-voltage.htm
 

·
Super Moderator
Joined
·
1,183 Posts
With the Fisker-supplied 120 volt charger I was getting charging rates that worked out to 13-ish hours for a full charge (never did a full charge, so this is all approximate). These chargers will in general slow down if they detect slightly-low-voltage on the outlet you have them plugged-in-to. A 30% slowdown (the 17-18-ish hour charge, vs ~13 hours) could mean that your voltage is low at the outlet, or you have something else on the same circuit (this will drag down the voltage while the "something else" is pulling current).
It could also be as simple as using an extension cord; an insufficient guage will introduce resistance and slow charging, or there could be something wrong with the L1 charger itself and not the Karma.
 

·
Registered
Joined
·
913 Posts
See the Wikipedia entry on battery balancing. I have no idea how clever the battery management system in the Karma is.

Some home-brew li-ion builders suggest not bothering with BMS-es, just make sure you get a batch of batteries from a single manufacturing run, and then run them all carefully paralleled so that they never get out of balance in the first place. Most commercial EVs have a management system of some sort, though.
 
1 - 20 of 22 Posts
Top