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Discussion Starter #1
Last summer was the first summer I had my Ampera. Also in the autumn, I was regularly getting 10.4kWh out of a charge. Then the winter came and the capacity dropped to about 9.6kWh out of a full charge. I was assuming, it's the cold affecting the battery capacity.

Last days are warm. Outside is sunny, with temperatures at 18°C. I use my OBD2 Bluetooth device to collect data from the car and the battery was at ideal 24°C. I was driving at about 60mph speeds on the highway.
So, warm weather, gentle ride on the highway and I'm still only getting about 9.6kW out of a charge.

Right now, with my Ampera parked in the garage, I have 9.2kWh consumed and 5km left in the battery. I haven't used any AC.

I don't think this is normal. The full capacity should be back now.

Does anyone have any idea, what's going on?
 

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There's some black magic involved in the calculations and/or the decision about when to switch to gas:

http://gm-volt.com/2013/02/26/a-tale-of-two-volts-the-summary/

I'm not sure I understand, but the conclusion seems to be that if you don't drain the battery all the way regularly, the car starts to think it has less actual capacity - but that "lost" capacity comes back if driven to CS regularly for a while.
 

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Discussion Starter #3 (Edited)
You could be right. I don't remember the last time I completely discharged the battery so that it would start the ICE and the last time I've used ICE was 6 weeks ago, because I was greeted with a EMM message yesterday, so I did some driving today in Hold mode.

I did get the ICE running due to low outside temperature, but I really don't remember, when was the last time I drained the battery completely.

Edit: Something similar has to be done with my Vectrix from time to time, as the battery gauge meter loses the correct charge capacity. The manufacturer of Vectrix suggests to drive until the red battery telltale appeared. That's the discharge cut-off voltage, when the bike knows, that the battery is fully discharged (SOC at aprox. 20%). Then it's suggested to fully charge the bike again, so that the bike's computer measures, how many kWh went into the battery. When completed, the bike knows the capacity of the battery and syncs the battery gauge bars according to the real battery SOC.
But my Vectrix has NiMH battery and it was made in 2007+. I thought that we're past this and that that's no longer necessary.
 

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Right now, with my Ampera parked in the garage, I have 9.2kWh consumed and 5km left in the battery. I haven't used any AC.
Well if you ran it to the ICE came on that would be darn close to 10.4kw ( 5km would be about 1kw )
 

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Discussion Starter #5
Well if you ran it to the ICE came on that would be darn close to 10.4kw ( 5km would be about 1kw )
5km would consume 1kWh if I used heating not without any AC. I'm getting about 46km/charge with heating on. Without any heating, I was getting 75km/charge last summer and autumn without any problems. That's 75km/10.4kWh = 140Wh/km * 5km = 700Wh.
9.2kWh + 0.7kWh = about 10kWh.

We're going for a longer trip and back this weekend. I will let it discharge all the way, both ways. On my usual longer drives I used Hold mode on highways and arrived with 2-3km left when I plugged the car.
 

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The kwh used doesn't care where the energy goes ... your still getting 10+kwh out of the battery, there is no issue
 

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5km would consume 1kWh if I used heating not without any AC. I'm getting about 46km/charge with heating on. Without any heating, I was getting 75km/charge last summer and autumn without any problems.
But the range estimator is still probably based on when it was cold. It doesn't predict what the weather will be or how you'll drive, it just goes off of recent past. So I'd guess 5km still equals ~1kWh in it's calculation. If you ran it to depletion, you'll probably find you end up with more that 5km left.
 

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Miles driven or km driven are key to me. You should rely more on how many kWh are put in during charge than the meter says during depletion. I'm glad my 2011 does not have the kWh meter.
 

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Discussion Starter #9
But the range estimator is still probably based on when it was cold. It doesn't predict what the weather will be or how you'll drive, it just goes off of recent past. So I'd guess 5km still equals ~1kWh in it's calculation. If you ran it to depletion, you'll probably find you end up with more that 5km left.
My range estimator doesn't go above 66km. It did show 72+km last year.
We also went on two longer drives this weekend. When battery was depleted, it switched to ICE. The first time it showed 9.5kWh used and the second time was 9.7kWh used.
I hope this improves, because last year I was regularly getting 10.3 or 10.4kWh used.
 

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I'm only get 9.9 kWh out of a full charge. This is consistent for winter and summer. Last time my Volt switched over to using the ICE was back in Feb 2012. I wonder if I started to use my ICE if the 9.9 kWh figure would go up.

I am basing the 9.9 kWh on when I lose each bar which starts right at 0.9 and is consistent for each 1 kWh after that.
 

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if its 18c outside and 24c in the battery, some power went into heating it.. (either resistive load or actual heading). Have you monitored the power usage when you first start. But those temps do seem above when I've seen the heater kick in.

While the NIMH had a chemically-based memory, which actually limited its maximum supplied power (if not properly conditioned0, the Lion still has difficulty in measuring capacity, which is separate. But if the car cannot accurately measure the SOC, it may start the car and even seem to have reduced capacity -- even when the capaicity is the same.

Check this thread..
http://gm-volt.com/2013/02/26/a-tale-of-two-volts-the-summary/
 

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Discussion Starter #12
It's 23°C outside temperatures these days, so the temperature shouldn't be a factor.

Yes, I've read that thread and since the weather is getting nicer, we're gonna have more longer trips, which should deplete the battery fully.
 

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What is HOLD mode and how do I tap into that?
 

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This is from the manual.
Hold Mode
Hold Mode is only available when the vehicle is in Electric Mode. This mode places the remaining battery charge into a reserve for the driver to use as desired. Selecting this mode transitions the vehicle to Extended Range Mode to maintain the battery charge reserve.
Upon exiting Hold Mode, the reserved battery charge becomes available again and the vehicle returns to Electric Mode. If the transition is from Hold Mode directly to Mountain Mode, the electric range displayed adjusts for the Mountain Mode charge reserve. Hold Mode will not change normal vehicle acceleration or braking performance.
Press the DRIVE MODE button to select Hold Mode.
Press the DRIVE MODE button again to return to Normal Mode and it becomes active after three seconds. The Hold light comes on when Hold Mode is selected. See Hold Mode Light on page 5‑22. Each time the vehicle is started, it will return to Normal Mode.
 

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Discussion Starter #16
After several full charge-discharge cycles with summer temperatures and battery temperature at 24+°C I'm still only getting 9.8kWh out of a charge :(
 

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After several full charge-discharge cycles with summer temperatures and battery temperature at 24+°C I'm still only getting 9.8kWh out of a charge :(
Numerous threads on this
This 9.8 kwH readout means very little.(and appears to be "typical" for a 2012 model)
Why would you expect it to be higher?

What range are you getting? That's all that matters (applying the three-Ts of course)
Things are still a bit cool so I would expect your range to improve as ambient temps increase

Just drive and smile!
WOT
 

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Discussion Starter #18
I was getting 10.4kWh per full discharge whole last year. Why the difference?
 

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There are various variables that affect the kWh display. These are discussed in a number of threads but it boils down to HOW the estimated kWh (and SOC values necessary to extrapolate it) are derived as well as specific correction factors.
In the end if you are getting the same range why would it concern you?
Range is the ultimate determining factor as to your available, usable capacity
So if you were getting 70km of range last year and it's still 70km (given similar T-T-T) that is all that matters
WOT
 

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Discussion Starter #20
Charging at EU 230V, 10A (2.3kW), 12.200Wh went in at the wall plug. Is that ok?
 
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