L went missing for awhile, huh?

[Pawl]

I've had my Spark for 2 months now. I've not read about this, but I hope it's something that the car simply does [to protect the batteries from overcharging].

My drive to work climbs 3000 feet. I can get two trips (35+ miles round trip) before having to charge for another work commute. This morning I plugged in at work to charge since it was low. I don't really need to, since my return trip is downhill and I can easily get home with little charge. Anyway, when I left work it was not full, but looked about 90%. I noticed on the way down that the L had no affect on region or to braking, none. In fact, in D the region only read 1 or 2 kW, where it usually averages 6-12, more or less, depending on how steep the section of road. Brakes worked fine, just not the typical regen charging nor the regen braking.

Was this because it was somehow protecting the batteries from overcharging (if that's even possible)? I have once or twice, charged up at work, but have not previously had this happen.

As a side note, the lower section of my drive home is flatter, with a few miles of freeway. The normal regen (with L effects) kicked back in after I left the mountainside.

Thanks in advance.

 

[FutureFolly]

That's definitely what happened. This gets even more frustrating if you live at altitude. Since you can't charge to a lower percentage, you have to waste the energy charging that you could have recovered on the road, and you're forced to use your real brakes that add to maintenance.

 

[NomadMac]

I posted about this phenomenon a while back. Sometimes, not always, when I have a full charge, L will not work when I leave my house. I, too, live on a hill. Kind of unnerving the first few times as it's unexpected and I always drive in L. I'm so used to driving in L in seems like the car is running away and out of control.

 

[SteveC5088]

Pawl, you definitely don't want to charge all the way up at work. That is wasting electrons AND wearing down brake pads needlessly!

Also, a note if you are not aware: When trucks descend a long grade, they have only so much braking capacity, much less than cars compared to the weight they carry. Therefore, they have to descend more slowly (ex. 35 mph), giving their braking systems more time to dissipate the heat generated. Going faster requires more braking, heating the brakes more. At some point, brakes will get too hot and two things occur: Rotors warp, and braking also fails. So be careful, drive slower if necessary.

Here is an EV site I refer to occasionally: Predicting Energy Use
From their research, they show a typical EV uses .25 kwh per mile on the flat, and climbing uses an additional 1.5 kwh per 1000' of elevation. Descending returns 1 kwh per 1000' or 4 miles of flat-terrain driving.

You need to stop charging at work when the battery is about 80% charged, so it has a reserve where you can charge up those extra 3 kwh.

Set a timer on your watch or something else to remind you to go unplug before charging is complete.

 

[Chaconzies]

Have seen this before when I first got the car, first time I charged on a level 2 at school had no regen for a few minutes. Basically, the car sees that the battery is already full enough and so it'll reduce regen, also if it's a steep hill then regen braking alone won't be able to totally slow and you'll have to use brakes.
I agree with Steve, start leaving work with a lower charge so you find the optimum level to leave at so you can regen brake all the way down.

 

[Pegasus]

Set a timer on your watch or something else to remind you to go unplug before charging is complete.

Or try the RemoteLink OnStar app which has a "Stop charging" button.

 

[Pawl]

Thanks everyone for the replies. I'll try limiting the charge to 60% up the hill.