Traffic Jam, Battery Goes South

daronspicher · 04-24-2007, 08:16 AM

I agree, there is no need to intervene, let the car handle itself and you'll be fine.

I also find the Prius (2006) to do poorly in the traffic jam situation. I've only been in one really bad jam for a little over an hour. Probably 20 minutes into it, the battery was bottomed out, so now the ICE is flailing around wildly with every 'creep ahead' for the next 40 minutes.

In this situation where you might think it would do great on mpg, it does it's worst.

I'm a little surprised it doesn't decided to regen the battery at some point and run the engine at some efficient rpm level for 4 or 5 minutes to bring the battery up to a usable level so the ice can kick on and off a lot less for the next little while.

Then, when you break out of the traffic jam, your mpg is in the toilet as the battery eventually recovers.

They have some basic parameters around protecting the battery, but I don't think they did a lot of tinkering to make it do anything cool in this situation.

nyprius2007 · 04-24-2007, 10:00 AM

same thing happened to me last night infact while waiting to cross the tz bridge..
battery went down to two bars and stayed there. Got the worst milage ever after that for a good 5 min. Nothing to worry about .. the computer will take care of it

richard schumacher · 04-24-2007, 11:22 AM

Further point: the main battery and associated electronics are cooled using *cabin* air, not outside air. That's the vent at the right end of the rear seat. You should use the A/C instead of opening a window, to avoid the possibility of the battery system getting too warm. If it does get too warm it will throttle itself and cause the car to run less efficiently. (Keeping the windows up also reduces infiltration of dust into the battery compartment.)

Walker1 · 04-24-2007, 01:43 PM

<div class='quotetop'>QUOTE(PaneInTheGlass @ Apr 23 2007, 09:05 PM) [snapback]428730[/snapback]</div>

Quote:

Hi folks, I'm brand new to this forum as is my new Prius, only three days and 300 miles old. I love this new vehicle and the fact that I'm already averaging 45 mpg out of the box.

Quick question: I was in a huge traffic jam on the way home from work this afternoon, it's 85 degrees, and traffic is inching along for more than five miles.

I begin monitoring the battery out of curiosity to see what will happen as I creep along for 45 minutes. The radio is on, the a/c is on (fan cut back to a notch above low speed). The battery level begins to drop from around 75% and continues to drop further around every 10 minures. Seeing this, I cut off all ancillary power, meaning, the radio gets turned off, the a/c is turned off, and the windows opened. Good thing there was no humidity.

Finally, traffic gets moving, but my battery has dropped to 25% (2 notches from the bottom). Is this a normal state for the Prius in traffic jams that are barely moving, or would I have been dead in the water within another 45 minutes?

Your responses are much appreciated. Other than this question, the vehicle has been perfect in all respects, I have package #5.

Thanks, Harv
[/b]

Yes, mine will do the same thing when heavy electrical demands are made on the battery. I shut off the A/C & headlights the other morning. The battery is supposed to go up & down depending on the load.

jamarimutt · 04-24-2007, 04:15 PM

It's actually quite bothersome when you're in a traffic jam, the battery charge drops very low and the ICE starts cycling on/off each time you move an inch forward and stop. To avoid this, step on the brake and press the gas pedal half way; the ICE will turn on, keep doing this until you get a couple of blue bars, take your foot off the pedal and the ICE will now stay off for a longer period of time.

A few folks have actually drag raced their Prius. They do the above, flooring the gas until the battery charges almost completely to obtain the best time.

neilw · 04-24-2007, 04:59 PM

<div class='quotetop'>QUOTE(jamarimutt @ Apr 24 2007, 04:15 PM) [snapback]429232[/snapback]</div>

Quote:

It's actually quite bothersome when you're in a traffic jam, the battery charge drops very low and the ICE starts cycling on/off each time you move an inch forward and stop.[/b]

I'm glad someone finally said this. When I first had the traffic jam experience, I was not so much concerned about the low battery, but driven nuts by the ICE cycling on and off. I mean, it was really monstrously annoying.

Quote:

To avoid this, step on the brake and press the gas pedal half way; the ICE will turn on, keep doing this until you get a couple of blue bars, take your foot off the pedal and the ICE will now stay off for a longer period of time.[/b]

Is this a documented feature? I'll have to try this...

auricchio · 04-25-2007, 04:22 PM

Be advised that the ICE/charge/battery behavior will also change depending on the temperature of the battery. You may never see the exact same behavior again.

hobbit · 04-25-2007, 05:22 PM

Recall that you get down to "two pink bars" territory if the car's
sitting powered up in Park, too. That's the default state when *not*
actually driving, and apparently when just creeping along too [but
then the juice is actually being used for propulsion]. Still a bit
of a mystery why the sitting-in-park state doesn't seek the 60%
level instead, but that appears to just be how it works.
.
_H*

04-24-2007, 08:16 AM	#11
daronspicher Join Date: Sep 2005 Posts: 1,205 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	I agree, there is no need to intervene, let the car handle itself and you'll be fine. I also find the Prius (2006) to do poorly in the traffic jam situation. I've only been in one really bad jam for a little over an hour. Probably 20 minutes into it, the battery was bottomed out, so now the ICE is flailing around wildly with every 'creep ahead' for the next 40 minutes. In this situation where you might think it would do great on mpg, it does it's worst. I'm a little surprised it doesn't decided to regen the battery at some point and run the engine at some efficient rpm level for 4 or 5 minutes to bring the battery up to a usable level so the ice can kick on and off a lot less for the next little while. Then, when you break out of the traffic jam, your mpg is in the toilet as the battery eventually recovers. They have some basic parameters around protecting the battery, but I don't think they did a lot of tinkering to make it do anything cool in this situation. __________________ My Lifetime MPG is: Lifetime Stats Down with VFTW, KeepTheBestIdol.com instead...

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04-24-2007, 10:00 AM	#12
nyprius2007 Join Date: Mar 2007 Posts: 14 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	same thing happened to me last night infact while waiting to cross the tz bridge.. battery went down to two bars and stayed there. Got the worst milage ever after that for a good 5 min. Nothing to worry about .. the computer will take care of it

04-24-2007, 11:22 AM	#13
richard schumacher Destination: Eschaton Join Date: Mar 2004 Location: United States Posts: 5,512 My Car: 2004 Prius Model: N/A Package: #6 Thanks: 99 Thanked 93 Times in 66 Posts Friends: 0	Further point: the main battery and associated electronics are cooled using cabin air, not outside air. That's the vent at the right end of the rear seat. You should use the A/C instead of opening a window, to avoid the possibility of the battery system getting too warm. If it does get too warm it will throttle itself and cause the car to run less efficiently. (Keeping the windows up also reduces infiltration of dust into the battery compartment.)

04-24-2007, 04:15 PM	#15
jamarimutt Senior Member Join Date: May 2004 Posts: 986 My Car: Model: Package: Thanks: 0 Thanked 2 Times in 2 Posts Friends: 0	It's actually quite bothersome when you're in a traffic jam, the battery charge drops very low and the ICE starts cycling on/off each time you move an inch forward and stop. To avoid this, step on the brake and press the gas pedal half way; the ICE will turn on, keep doing this until you get a couple of blue bars, take your foot off the pedal and the ICE will now stay off for a longer period of time. A few folks have actually drag raced their Prius. They do the above, flooring the gas until the battery charges almost completely to obtain the best time.

04-25-2007, 04:22 PM	#17
auricchio Senior Member Join Date: Mar 2006 Location: Cambria, CA, USA Posts: 904 My Car: 2006 Prius Model: Package: #8 Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Be advised that the ICE/charge/battery behavior will also change depending on the temperature of the battery. You may never see the exact same behavior again.

04-25-2007, 05:22 PM	#18
hobbit Senior Member Join Date: Mar 2005 Location: Bahstahn Posts: 3,626 My Car: Model: Package: Thanks: 0 Thanked 216 Times in 118 Posts Friends: 0	Recall that you get down to "two pink bars" territory if the car's sitting powered up in Park, too. That's the default state when not actually driving, and apparently when just creeping along too [but then the juice is actually being used for propulsion]. Still a bit of a mystery why the sitting-in-park state doesn't seek the 60% level instead, but that appears to just be how it works. . _H*