Traction Batt Health: 7 Bars good or bad?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by wjtracy, Jan 26, 2012.

  1. wjtracy

    wjtracy Senior Member

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    Lately here at 100k miles, my MFD display is showing very nice high level of EV batt charge - generally 7 bars in the GREEN almost all the time. MPG good at 50 but did have one really low MPG tankful.

    Good or bad news re: 7 bars most of the time? The only things I can think of, heat is on so maybe ICE engine runs more in winter? Or perhaps my EV fan is clogged so the EV battery is too hot giving higher SOC reading?
     
  2. Codyroo

    Codyroo Senior Member

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    I seems to recall in another post that Tom (QBEE42) mentioned that a high battery reading is not good. I'm assuming he meant a sustained high battery reading. If you are driving along doing your normal operations and the battery is staying high, it might be an issue.

    Others with more knowledge will weigh in soon enough.
     
  3. efusco

    efusco Moderator Emeritus
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    I think you're on track with the cold weather ICE running more which spills excess energy into the traction battery and tends to keep the SOC higher in the winter.

    The main signs of 'bad health' of the battery are dramatic and rapid swings from very high SOC (8 bars usually) down to 1 or 2 pink bars without some really good reason for it.

    I would deem what you're reporting as totally normal winter operation.
     
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  4. seilerts

    seilerts Battery Curmudgeon

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    If the canoe is any indication of a very active lifestyle, traveling on dirt roads and hauling lots of stuff in the back, now would be a good time to clean that battery fan. There are definite driveability problems when the battery is running too hot (i.e. clogged fan), particularly take off from a standing stop, there will be hesitation.
     
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  5. wjtracy

    wjtracy Senior Member

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    ...unfort the canoe 99.9% of the time is in my backyard. But for 100k mile service I will try to have the fan checked. If I do this I will ask for pic to show. My case is non-severe use (checked with my wife to verify the dog died before we got the Prius) so hoping my fan is clean, but if not that'd be interesting.
     
  6. 2k1Toaster

    2k1Toaster HID Guru

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    It probably won't be clean at 100K miles, but it won't be clogged an unable to spin which is bad.

    Like others have said, when you run the heat, the engine turns on to make heat. If you don't need the engine to move forwards, it dumps that waste energy into the battery.
     
  7. F8L

    F8L Protecting Habitat & AG Lands

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    I cannot answer your question but I generally observe mostly green bars and an SOC of 60-65% during normal operation. I usually only see blue bars when working harder. Otherwise I maintain what appears to be a high SOC if you just look at the MFD but the Scangauge says I am right where I should be. My mpg is the same as always with an average summer high of 55-57mpg with my 15s or 45-47mpg with my 17s.... I'd rather not discuss winter mpg with the 17s. *cry*
     
  8. wjtracy

    wjtracy Senior Member

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    OK thanks all, it (Green bars) sounds like good thing for now.
     
  9. qbee42

    qbee42 My other car is a boat

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    It's neither good nor bad; it all depends on why a Prius has all green bars. In winter operation it is not uncommon, as the ICE has to run to make heat. I suspect that is what yours is doing.

    Tom
     
  10. Rokeby

    Rokeby Member

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    Just a thought...

    have you checked the little guy, the 12V battery, lately?