Gen II Prius Individual Battery Module Replacement

Discussion in 'Gen 2 Prius Technical Discussion' started by ryousideways, Apr 24, 2013.

  1. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    I would first like to state that when all of this is said done and figured out I will be making a write up of what to do.

    I have a 2005 Prius with 114,000 miles on it. I was driving last week when it suddenly displayed a Christmas tree of lights that included VSC and the triangle of death....and of course the battery fan kicked into high gear.
    Hooked it into a OBD II scanner:
    P0A80 "Hybrid battery pack over temperature"
    P3019 "battery block 7 becomes weak"
    P3000 "DSL solenoid circut low"
    P0300 "random misfire detected"
    P000A "engine position system performance- bank 1"
    Also C1241, C1242, c1249, c1259, c1310, c1357

    I went ahead and cleared the codes. The angry lights went away but came back within minutes of driving. The car went into limp mode but I was able to make it home.

    After some research here and watching this video:
    - A look at what the individual modules look like

    - how to tear down your prius to get to the battery

    So I tore down the prius and placed the battery pack on my work bench. After carefully disassembling the pack and removing the bus bars I performed a load test using a 55 watt halogen bulb.
    The result showed a even distribution of voltage around 7.60
    For those interested here are the results:
    7.62
    7.65
    7.63
    7.62
    7.62
    7.61
    7.60
    7.60
    7.60
    7.60
    7.61
    7.61
    7.61
    7.60
    7.61
    7.60
    6.12 <---- low
    7.60
    7.60
    7.29 <---- low
    7.61
    7.59
    7.62
    7.60
    7.60
    7.63
    7.65
    7.64

    So from there I determined I needed to replace those 2 modules with dropped voltage. I ordered some used ones from a hybridautocenter.com (found on ebay for $35 a piece) The new modules arrived and tested at 7.73 and 7.63 volts. I replaced the bad modules with the new ones and drained and charged each battery to match 7.60 volts. Please let me know if this is a incorrect technique. If a module was too high I used the 55 watt bulb to drop it to 7.60 and if it was too low I used a 6v/6amp car battery trickle charger to bring it up. I waited 15 minutes then tested all of the batteries voltage without a load and all of them were at 7.60 or 7.61. I reassembled the pack, placed it back in the car and went for a 5 mile test drive prior to putting the interior back together. Drove it on the highway and it seemed fine so I put the interior back together.

    This evening I decided to take it out for another test drive and when I hit about 15 miles the triangle of death appeared again. I got home and found this time it is throwing code P3015. I also noticed that the battery bars on the screen seem to be staying in one place. Not charging or discharging. I cleared the code and it came back after a 5 mile drive.

    SO! I did further research and just found out that there as a special way you have to balance them? From what I understand I need to purchase a supermate DC6 charger?
    Dynam Supermate DC6 DC Multi Function Balance Charger/Discharger 1-6 cell Lilo/LiPo/LiFe, 1 to 15 cells NiCd NiMH
    I figured I would buy 7 of them since the infamous Seilerts has 14 and can do it in 3 days I figure 6 days would not be so bad. My other question is there a possibly that I simply did not plug something in to be throwing this code? Thoughts? Suggestions? I am not going to buy a new, used, or refurbished pack if I am able to fix the one I have.
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    75,096
    31,237
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    sorry, can't help, but great first post! welcome to p/c and all the best with your battery work.(y)
     
    WilDavis and Ajourney101 like this.
  3. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    Thanks! I have only been an occasional lurker until now. Then again, this is the first time I have ever had any problems with my Prius. Hopefully somebody can point me in the right direction from here.
     
    Ajourney101 likes this.
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    75,096
    31,237
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i'm sure they will. quite a few experts in the battery stuff. just takes time for people to see the post. you can probably do some more research in old threads while you're waiting, there is quite a bit of info available. good luck!
     
    Ajourney101 likes this.
  5. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,193
    1,811
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    The normal method of restoring the HV battery is to use the DC6 charger. This is used to charge or actually over charge each module then discharge monitoring the discharge capacity each time. This is because each module contains 6 cells one or more of which could be in a lower state of charge than the rest of the cells in that module.

    If you slightly over charge the module the cells that are fully charged do not accept any more charge and give the energy off as heat, any cells that are not fully charged continue to charge and catch up with the rest of the cells in that module. This is what we call balancing the module " balancing the charge in all the cells in that module".

    Charging and discharging three times and monitoring the capacity each time will usually show any improvement in the capacity and the actual capacity of the module. The capacity of any module will be that of it's weakest cell.

    To build your battery for a gen2 Prius you need 28 modules (gen1 needs 38) of as near equal capacity as possible. If you have a module with a lower capacity than the rest that module will become discharged faster than the others to the point that when it becomes fully discharged it is forced into being reverse charged by the rest of the modules destroying it.

    Hope this helps.

    John (Britprius)
     
  6. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,172
    1,213
    1
    Location:
    Trumbull, CT
    Vehicle:
    2016 Prius
    Model:
    Three
    Besides getting all of the modules balanced, at comparable capacity, and equal voltage, you should:
    • Measure module series resistance and any that are noticeably higher than the others should be replaced.
    • Let all modules rest for a while and determine that their voltage stabilizes to a very slow self discharge rate. Any the exhibit higher self discharge rate (after the first 24 hours when the surface charge dissipates) than 0.1v/week will not have a long life in the HV battery.
    Buying multiple DC6 chargers (that is the one I use) will speed up the process and remember to clamp modules being charged/discharged as internal pressure builds up which can cause the sides to bulge. Using your 6 amp charger can damage a module as it does not have the sophisticated capability to control the charging rate as the cells approach full charge.

    JeffD
     
  7. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    Thank you both for the assistance! I had initially checked the voltage when it was not under load. One of the modules was obviously bad because of the much lower voltage(Module #17 @ 6.47V). The other one (Module #20 @ 7.29V) I was suspicious of so I ordered a replacement anyways. I then confirmed a few days later that the voltage of module #20 had dropped significantly to 6.76V. It took a week for the batteries to arrive and I retested their voltage before replacing the two modules. The car runs and drives but still throws the angry triangle and VSC after 10 minutes of driving. My mini OBD II reader is showing P03015. Currently I am waiting to get my friends more in depth OBD II scanner so I can see if it is throwing any other codes. I will report back as soon as I get the code reader.

    So just to confirm, DC6 chargers are required when a gen II prius battery pack is rebuilt? And each individual module must be rebalanced prior to reinstalling the battery pack to the car?
     
    Ajourney101 likes this.
  8. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,193
    1,811
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    The DC6 chargers are not the only one's but probably the quickest to obtain at a good price but beware they do not or often do not come with the supply unit. It is a good idea to use a good 12 volt car battery on charge as a supply for the chargers as this will continue to work even with a power outage without loosing any data.

    John (Britprius)
     
  9. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,172
    1,213
    1
    Location:
    Trumbull, CT
    Vehicle:
    2016 Prius
    Model:
    Three
    Remember to clamp any module being charged/discharged to avoid bulging side walls due to internal pressure build up (Seilerts keep them clamped in the HV battery pack and works on every other one to control over heating, I did one at a time clamped between two 2x4 scraps with a c-clamp). Next time I would at least buy 4 DC6's to get the job done in a reasonable amount of time.

    JeffD
     
    Ajourney101 and gdanner like this.
  10. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    Quick update: I grabbbed the good OBD II scanner and it is showing the following codes:

    U0100 "lost communications with ECM/PCM "A""
    U0111 "lost communication with battery energy control module "A""

    This leads me to think maybe something did not get plug in all the way... *sigh* Guess I may as well tear it down again....

    In the mean time the car has been driving fine with the exception of the angry triangle. The batteries do not seem to be feeling hot. Before I replaced the 2 modules I could feel the case was overheated. I will go ahead and order 4 of DC6 chargers but I need to drive it in the mean time. If my math is correct charging everything should take about 10 days with 4 chargers.


    I will leave the batteries compressed in the case but do I need to clamp the outside of the individual batteries as well?
     
    Ajourney101 likes this.
  11. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,172
    1,213
    1
    Location:
    Trumbull, CT
    Vehicle:
    2016 Prius
    Model:
    Three
    Extra clamping is only required when the modules are out of the battery. Allow for air circulation to control heat.

    Jeff
     
  12. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    318
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    I am keenly watching these threads about battery rebuilding. I am wondering about the article at Luscious Garage, where she says that they won't try rebuilding now, as it does not seem to be a long term solution for the sort of people they see. The idea is that module tolerances are supposedly so tight that if one or two start to go, the others won't be too far behind. As the individual modules get replaced, then the concern is that others will show up as weak, which I guess is what P3015 now coming up is about.

    So I commend those that try the low cost DIY approach, as that is what I tend to do, and hope this results in satisfaction.

    As for the loss of communication DTC, that could be at the battery ECU plug. Since it is in the back of the car, improper termination of the network could cause reflections that will make noise and CAN bus errors at other ECU's.
     
    Britprius likes this.
  13. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    Another update: I partially took apart the battery casing just enough to get to the battery ECU. I checked all the connections and everything looked ok until I pushed in on the red clip at the bottom of the battery ECU.

    "Click."

    Oh....

    And from there I felt dumb....until I drove it for another 20 miles and the triangle came back. This time it is the same codes:

    U0100 "lost communications with ECM/PCM "A""
    U0111 "lost communication with battery energy control module "A""

    in addition to:


    P3015 "battery block 3 becomes weak"

    I will go ahead and order those DC6 chargers tonight. Hopefully this is just a result of the batteries not being balanced.
     
  14. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,193
    1,811
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    I think your problems arise from not balancing all the modules.

    nh70 is correct about possible battery life with rebuilding. However it still makes economic sense to rebuild the HV battery yourself even if it only lasts one or two years then needs doing again, and may well last much longer. This is the route I would take "if" the need arises with my own car, having successfully rebuilt a battery for a friend two years 30,000 miles and counting ago.

    From a company point of view it probably does with the time involved and needing to give reasonable guarantees.

    It is also a much greener option to use as much of the life still in usable modules both from your own battery and the purchased downer modules.

    John (Britprius)
     
    Eddy2014 likes this.
  15. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,193
    1,811
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Previous DIY rebuilders have reported some modules only having around 3 AH capacity on the first charge. After 3 balancing cycles this has gone above 6.5 AH the rating for the modules. It is important to remember that the capacity of a module is that of the weakest or lowest charged of it's 6 cells.

    John (Britprius)
     
    Eddy2014 likes this.
  16. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    318
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    Reading the service manual, I think the U0100 and U0111 are correlated, as they talk to each other over the CAN BUS. Which is to say, I think the problem is with the battery ECU, and fixing that will cause the U0100 to resolve. The procedures all say to check the CAN BUS for opens or shorts and that sort of thing. So look over the wires to the battery module, hopefully you will find a nick or pinch. Here is a quick test to see if continuity is good to the front of the car.
     

    Attached Files:

  17. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    I decided I will go pick up two Hitec X4 chargers from the local hobby shop. I should be able to charge 8 modules at once with these.

    X4 Four-Channel Multicharger

    My only issues is finding an appropriate power supply for the chargers. I have a few computer power supplies around the house. I have seen a few diy instructions on how to use them for a DC charger.
    Convert an ATX Power Supply Into a Regular DC Power Supply!

    Apparently a standard laptop charger does not generate enough power according to here:
    Is there a guide to how to rebuild the battery pack? How many cells does it need? | PriusChat

    I may just break down and buy a power supply from the hobby store.
     
    wb7doj and NortTexSalv04Prius like this.
  18. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,172
    1,213
    1
    Location:
    Trumbull, CT
    Vehicle:
    2016 Prius
    Model:
    Three
    These hobbyist charger/rebalancers are intended to be supplied from a 12v car battery. Just hook up a car battery to a battery charger that can keep up with the required peak power (16 amps for one unit, 30 amps for two units). If the battery can handle a charging cycle alone, you can use a smaller charger since there will be a long period (the discharge cycle) when the charger can get the car battery back to full charge.

    JeffD
     
    gdanner likes this.
  19. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,193
    1,811
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    The 12 volt power supply from a computer will work fine. The yellow and black output wires are a 12 volt regulated output, Yellow positive +, black negative - . A 12 volt car battery on a charger is a better solution because it is the equivalent of an UPS.

    John (Britprius)
     
    Ahyour likes this.
  20. ryousideways

    ryousideways Member

    Joined:
    Apr 24, 2013
    35
    81
    0
    Location:
    Merritt Island, Florida
    Vehicle:
    2005 Prius
    Model:
    II
    May be a odd question but would I be able to use the 12v battery from the prius? Or should I just go pick up a standard car battery?

    It would connect as follows:

    wall outlet ---> 12v car battery trickle charger ---> 12 car battery ---> two Hitec X4 Four Channel Multichargers---> 8 modules
     
    j12piprius likes this.
Loading...