Sudden catastrophic loss in range

I am not sure if my main battery pack is failing or not but this is what happened.

It's scorching hot today and I was driving home on the 5. When I got going from Glendale to Burbank, I went surface streets to the freeway onramp...started with 105 miles and by the time I got to the freeway, it was about 101 miles. I had to a fast burst to get onto freeway. Once I merged in, traffic slowed and then I looked down a few seconds later and it had dropped to 45 miles...and it was still dropping...every 3-4 seconds by about 1 mile.

I quickly exited and drove surface streets home for the next 3 miles. I stabilized at 32 miles. I disconnected the 12V battery once home and reset the vehicle to no avail. I had 57% when I plugged in the car.

Any ideas what's going on guys and gals?

How many bars did you start with, and how many did you end with?

1. Did you start the drive fully charged?
2. Did you look at the energy screen to see how many kWh you had used since it was fully charged?
3. What percentages had been used by HVAC, battery conditioning, and driving?
4. When you turned the car off, what was the distance and mi/kWh for the trip displayed on the instrument cluster?

If you started with 105 miles, you've obviously been driving like a good boy in good weather for a while, so the car starts with the assumption that will continue. If conditions change to a higher temperature, you're going to have a sudden decrease in estimated range due to HVAC and battery conditioning power use. If conditions change to high power use for driving (hard acceleration, high speed, etc.), you're going to have a sudden decrease in estimated range due to driving power requirements.

I see this very clearly when I race my car...I can go from 90 miles of estimated range (with a full charge) to 45 miles of estimated range in less than 5 miles of driving! The guessometer has to make some assumptions based on previous driving habits and current use, then extrapolate out to the future...so rapidly changing range estimates are assumed when you have rapidly changing usage conditions.

Bryce

I had almost full charge when I started driving from Glendale....I had one bar above half when I ended at the garage.

I have never gotten below 3.2 miles/kWh when I switch off the car...when I did this time I had 1.0 miles/kWh. It was dropping like I rock...every 3-4 seconds it was dropping a mile in range forcing me to exit.

My battery conditioning has never registered above 0%. I was at about 5% HVAC and 37% vehicle use. Roughly about 8.1 kWh used or so.

What concerns me is the incredibly sudden drop in range....I've raced or gunned it hard...but it's never ever dropped 50-60 miles all of a sudden. I've seen 10 mile drops but this was unexpected and it continued to drop rapidly. What's more, I didn't gun it that hard this time around....

I suspect it's the heat having to play a huge factor. I hope it is...I really truly do not feel like having the car taken to the dealer....again.

Wow, that's worrisome. Got to believe it's heat related, but how?

Please keep us posted on what you find out...

Sesamecrunch said:

Wow, that's worrisome. Got to believe it's heat related, but how?

Please keep us posted on what you find out...

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Yeah it is worrisome. And what's more...now when I charge back up, my full charge doesn't go back to what I would usually get...which is around 105-110 miles of charge. I'm lucky to get 85 miles now. It's almost as if 4 kW of capacity has been removed from my battery pack....could a portion of the battery have gone bad?

I also notice now that when I drive the car, the fluctuations in range are more dramatic...indicating to me a smaller capacity with which the battery is charging and discharging with.>>WTF is going on? And for this particular incident, I drove hard for a few seconds...not constantly over a period of time...I accelerated hard for about 3-4 seconds and then was in stop and go traffic again. Does this really suggest that such a small episode of acceleration is going to wack 60 miles off of my range in less than a minute and then reduce my battery capacity permanently by 3-4 kWh? If so that's disastrous.

One more thing...I don't know if you guys notice this or not but I've never seen my battery conditioning percentage move from 0%...not even on the last few hot days...it's very strange.

The problem was probably a freak out by the computer simply because the system would have detected if cells in the battery pack died. Voltage would drop. Lights would be flashing. Power would be limited. If it was the battery pack that caused the problem it might be a single cell that died. I think the car would detect even one failure though.

Did you shut off the AC immediately when the probably started? It may have been running the compressor for the AC almost continuously consuming quite a bit more power than normal.

A cooling system problem is possible too. The water pump may have failed. The radiator being from the gasoline Spark makes me think the car should normally be able to cool itself in fairly intense heat. If the batteries were running hot the computer may have drastically cut range and power to protect the pack.

FutureFolly said:

The problem was probably a freak out by the computer simply because the system would have detected if cells in the battery pack died. Voltage would drop. Lights would be flashing. Power would be limited. If it was the battery pack that caused the problem it might be a single cell that died. I think the car would detect even one failure though.

Did you shut off the AC immediately when the probably started? It may have been running the compressor for the AC almost continuously consuming quite a bit more power than normal.

A cooling system problem is possible too. The water pump may have failed. The radiator being from the gasoline Spark makes me think the car should normally be able to cool itself in fairly intense heat. If the batteries were running hot the computer may have drastically cut range and power to protect the pack.

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That's plausible....never thought of that...but like you said, if it did cut power and range, would you not expect an alert?

I checked for leaks but I couldn't find any. I guess we shall see in the next few days as the weather returns to normal what happens to my range....but it was very very strange. I did do a 12V battery reset but that didn't fix a thing in terms of range readout. And the HVAC percentage wasn't out of line as shown in the energy use display.

I think your battery assembly got so warm in this heat that its output went down accordingly. I think it will be fine as the weather lets up, finally.

Hope I'm right

StevesWeb said:

I think your battery assembly got so warm in this heat that its output went down accordingly. I think it will be fine as the weather lets up, finally.

Hope I'm right

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But isn't this Liquid Cooled ?
This is one of the other reasons I really want this car.

I wonder if it had something to do with the AC ... I'm not an electrical guy so I'm not sure. But maybe a computer module is out of whack that detects power left ?

tigger19687 said:

StevesWeb said:

I think your battery assembly got so warm in this heat that its output went down accordingly. I think it will be fine as the weather lets up, finally.

Hope I'm right

Click to expand...

But isn't this Liquid Cooled ?
This is one of the other reasons I really want this car.

I wonder if it had something to do with the AC ... I'm not an electrical guy so I'm not sure. But maybe a computer module is out of whack that detects power left ?

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Not sure...could be. Something was out of whack that much I can say with certainty.

Let's hope Steve is right and things just go back to normal.

FYI...here are some readout images from the display screens I took today for the record. I started out with 89 miles today. Higher than I expected but still far lower than my usual 105-112 mile topoffs I've been seeing for the last 2 months.

This first image shows my energy history for the last 50 miles when I first started driving the car today. You can clearly see the huge dip in energy use where the range drop incident occurred:



You can also see in this next picture my average consumption over the 2400+ miles I've had...it was 5.5. miles/kWh until this catastrophic power drain. Clearly you can see it was a massive drain...it's over a 5 mile period for each bar yes? This from a few seconds of acceleration?? And enough power drain to cause my average to go down even after all these miles?



You can see in this next picture the readouts once I got home. Much of my drive home was downhill but with A/C on.









And of course after I shut down the car....



My energy history and miles/kWh are clearly show....decent numbers.

At 79 miles at shutdown, I used 5.4 kWh....at 5.4 miles/kWh I should charge back up to about 108 miles. (79+29). Correct? If I don't charge back up to a value close to that, this would indicate battery capacity reduction which has, somehow not thrown a fault.

You will also note that I've NEVER ever seen my Battery Conditioning % show anything other than 0%. I find that incredibly odd because as a few are suspecting here, it could have been due to heat correct? Well the conditioning system should have been working overtime to cool the battery correct? Even a 1% blip should have shown up...but it never has for the entire ownership of this car.

My energy use is also quite consistent and well above 4 miles/kWh most of the time. Never has it dropped below 3.0. This has been my driving style since I bought the car.

I would suspect a software or possibly a hardware fault in the instrumentation rather than any battery problem.

In general the system does not and cannot indicate the actual battery capacity.

The only information that is available is the amount of charge going in and out of the battery and the battery voltage.

Unless the battery is almost discharged the battery voltage does not provide very useful information about the state of charge of the battery. This is one of the big problems with electric vehicles (and all other battery powered devices) in that it is not possible to get accurate state of charge information. Most systems have to assume a certain battery capacity and only recalibrate when the battery is fully cycled from empty to full (or full to empty).

kevin

kevin said:

I would suspect a software or possibly a hardware fault in the instrumentation rather than any battery problem.

In general the system does not and cannot indicate the actual battery capacity.

The only information that is available is the amount of charge going in and out of the battery and the battery voltage.

Unless the battery is almost discharged the battery voltage does not provide very useful information about the state of charge of the battery. This is one of the big problems with electric vehicles (and all other battery powered devices) in that it is not possible to get accurate state of charge information. Most systems have to assume a certain battery capacity and only recalibrate when the battery is fully cycled from empty to full (or full to empty).

kevin

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Kevin,

If your statement is true, why do you suppose there hasn't been any fault indication? How would one detect such a fault? What's the remedy? Flash the computer? Remove the 12V battery overnight and see what happens perhaps?

You could always take it to the dealer and ask them to check into it.

GeekEV said:

You could always take it to the dealer and ask them to check into it.

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I could but it'll be fruitless....without any codes of any kind they are useless.

nozferatu said:

kevin said:

...

Kevin,

If your statement is true, why do you suppose there hasn't been any fault indication? How would one detect such a fault? What's the remedy? Flash the computer? Remove the 12V battery overnight and see what happens perhaps?

Click to expand...

Click to expand...

I agree it is surprising that no error was indicated but for some reason the car seems to think that the power consumption was something like 5 times the normal level for 5 miles. Maybe a software problem. Presumably there isn't any error threshold on that level to trigger an error indication. I don't think it is anything to do with the battery.

Rather than leave the energy display on the trip meter, I reset that every time I charge and then keep track of the lifetime average in a spreadsheet. That way I can get the average energy consumption per charge easily. The DC energy consumption is from the energy screen.

My average over 4500 miles is similar to yours with 5.6mi/kWh DC and 4.9mi/kWh AC.

kevin

kevin said:

nozferatu said:

kevin said:

...

Kevin,

If your statement is true, why do you suppose there hasn't been any fault indication? How would one detect such a fault? What's the remedy? Flash the computer? Remove the 12V battery overnight and see what happens perhaps?

Click to expand...

Click to expand...

I agree it is surprising that no error was indicated but for some reason the car seems to think that the power consumption was something like 5 times the normal level for 5 miles. Maybe a software problem. Presumably there isn't any error threshold on that level to trigger an error indication. I don't think it is anything to do with the battery.

Rather than leave the energy display on the trip meter, I reset that every time I charge and then keep track of the lifetime average in a spreadsheet. That way I can get the average energy consumption per charge easily. The DC energy consumption is from the energy screen.

My average over 4500 miles is similar to yours with 5.6mi/kWh DC and 4.9mi/kWh AC.

kevin

Click to expand...

Ok I'll try that and see...I'll also reset my mi/kWh readout and see how that compares.

I had a similar thing happen to me this morning. I've had my Spark for just three weeks shy of one year and have a bit over 13k miles, drive pretty much the same commute everyday and I have averaged 123 MPGEe for the life of the vehicle.

This morning starting out I had a range of 80 miles showing on the 'Guess-o-Meter' (drove it a bit hard yesterday afternoon trying to get home in time for the start of the LA Kings game...boo they lost game 4) and about 15 miles into my commute (freeway w/o A/C and radio on) my battery dropped to 54% with a range of 34 miles remaining out of the blue? Normally I will have approximately 70%+ battery life and 63 miles (+/-) of range remaining at the end of my 25 mile commute to work. Also the trip showed 2.9 miles/kWh for the 25.4 mile trip, normally it's above 4.5...very strange.

I contacted OnStar and basically they were of no help telling me to contact the dealership if it happens again (ugh). I've been quite happy with the car up to this point but I'm really glad this car is a lease...