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

Hybrid batteries

Discussion in 'Gen 2 Prius Main Forum' started by Lodrun, May 8, 2020.

  1. Lodrun

    Lodrun My proper car is an MGC

    Joined:
    Feb 18, 2010
    21
    3
    0
    Location:
    Cheltenham
    Vehicle:
    2007 Prius
    Model:
    N/A
    During UK lockdown I am using the Energy Monitor graphic to keep a check on the charge state of the main batteries on my 2007 Prius. If I park the vehicle with 6-7 blue bars showing, after a few days, it can be down to 2 bars. After 6 miles of driving it is back up to 6-7. Should I be concerned about this? The car starts and drives perfectly but I am worried that if the charge falls to zero bars it might not power-up. It is not a practical long-term proposition to have to drive the car every two or three days just to prevent the main batteries exhausting.

    Also, does anyone know the significance of the different colours used to show the battery state bars on the Energy Monitor screen. They can be dark blue, light blue, purple or green (at least) and I have no idea why.
     
  2. MickyMatter

    MickyMatter Active Member

    Joined:
    Mar 2, 2015
    260
    167
    0
    Location:
    Germany
    Vehicle:
    2008 Prius
    Model:
    II
    The color of these bars correspondences with their number and the SoC.
    Here's a table:
    SOC – Prius Wiki

    SM-G950F ?
     
    SFO likes this.
  3. Lodrun

    Lodrun My proper car is an MGC

    Joined:
    Feb 18, 2010
    21
    3
    0
    Location:
    Cheltenham
    Vehicle:
    2007 Prius
    Model:
    N/A
    Many thanks for this. Even one bar seems to represent at least 40% charge, which is encouraging. I seem to get three shades of blue (light, medium and purple), which doesn't tie up with the table
     
  4. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,518
    14,128
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    Looks like the traction battery is getting old. Reconditioning might help, but that's more for balancing the cells than for rejuvenating the chemistry.

    You're right about the fact that the car keeps a reserve, but it sounds like that reserve would drain away pretty quickly. I'd suggest pairing up the Dr. Prius app on your phone with a bluetooth OBDII adapter and running a diagnostic to give you an idea of the battery's health.
     
    SFO likes this.
  5. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,404
    6,062
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    Yes, those are early indications that you have one or more modules becoming significantly weaker than the others. Typically due to self discharge of one of the 6 internal cells in the module.
     
  6. donzoh1

    donzoh1 Active Member

    Joined:
    Jan 19, 2019
    441
    151
    0
    Location:
    Lenexa, KS
    Vehicle:
    2004 Prius
    Model:
    Five
    Is there a battery rebuild guide? Would these be similar in all prius generations?