1. Attachments are working again! Check out this thread for more details and to report any other bugs.

HV battery capacity decreasing over time?

Discussion in 'Gen 1 Prius Plug-in 2012-2015' started by Ichiro, Dec 1, 2014.

  1. Ichiro

    Ichiro Member

    Joined:
    Apr 25, 2008
    335
    13
    0
    Location:
    SF
    Vehicle:
    2008 Prius
    Back in 2012 when I first bought my PIP, the battery charge level as indicated by range was 17-18 miles. The energy to fill the battery has been consistently ~2.5-2.7 kwh.

    Earlier this year it dropped to about 15 miles. And just recently it's dropped to about 13.5 miles. The weather has gotten cooler in the last few weeks here in SF, so I don't know how much of this is seasonal as I haven't been keeping track that closely.

    I expect to see charge capacity loss over time for the main LiON battery and would like to know what to expect and if my PIP is typical. How much further decrease should I expect in the next couple years? Is your PIP doing better or worse than mine?
     
  2. Jerry Liebler

    Jerry Liebler Member

    Joined:
    Jan 12, 2014
    177
    85
    0
    Location:
    Science Hill Kentucky
    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Base
    Are you speaking of actual range (miles actually driven in EV) or the range estimate as given on the MFD? The range estimate is based on recent driving history and the battery's state of charge, temperature etc. Actual range is highest at about 80f and falls off with lower temperatures.
     
  3. Ichiro

    Ichiro Member

    Joined:
    Apr 25, 2008
    335
    13
    0
    Location:
    SF
    Vehicle:
    2008 Prius
    I was referring to the estimated miles which I assumed somehow correlated to the HV battery charge level. I didn't realize that the range was also correlated to other factors.
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    the estimated range is almost useless. you would have had to do a defined route, at a defined speed, at a defined temp/humidity when your pip was new, and then repeat each time you want to measure it. that's the only way to get a handle on it. you can start now, if you want to measure future degradation.

    fwiw, my estimate has dropped about 1 to 1/2 miles at peak time of year, and my actual is probably down a half mile or so, but i'm not absolutely positive. i do have 17,000 miles of ev.
     
  5. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,080
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I wouldn't look at the number of miles anything. Just keep track of how much energy it takes to fully charge the battery from fully empty and what the temperature is during those charges. I.e. if it is too hot the fan will come on and drain power which makes it look like the battery pulled more power.

    In the EV world, some estimates say you could lose 10% capacity in the first year and 1%-2% each additional year but that is for a full EV which may use 100% of its battery capacity and thus stress the battery much harder than a PHEV like the Prius and Volt which use only a portion of the battery to extend longevity. However, ambient temperatures play a big role in battery degradation and lack of thermal management systems and high average temps can cause a battery to degrade faster. Being in SF you shouldn't have much of an issue with this though as your average temps are ideal for EV batteries. :)

    Battery Capacity Loss - Electric Vehicle Wiki