A new journey with my 2005 Prius

Discussion in 'General' started by Ophbalance, Jan 18, 2017.

  1. Ophbalance

    Ophbalance Administrator Staff Member

    It's not been a very pleasant week. Of the new tires I put on the Sedona two weeks ago (by hand), one has had a three inch blowout in the tread. The backpack that holds my laptop popped it's zipper on the way out the door yesterday. It took TWO hours to drive 50 miles into work in stop and roll traffic. And then... this:

    This is not a code you ever want to see show up. Ever. 'E's not pinin'! 'E's passed on! This hybrid 0is no more! He has ceased to be! 'E's expired and gone to meet 'is maker! 'E's a stiff! Bereft of life, 'e rests in peace! If you hadn't nailed 'im to the perch 'e'd be pushing up the daisies! 'Is metabolic processes are now 'istory! 'E's off the twig! 'E's kicked the bucket, 'e's shuffled off 'is mortal coil, run down the curtain and joined the bleedin' choir invisible!! THIS IS AN EX-HYBRID!!

    Which is to plainly say that the traction battery is no more. Specifically it's indicating that cell #5 has kicked the proverbial bucket.

    My car, as a 2005, is 12 years old and has 172,000 miles on it. I can't see the point of spending whatever it is mother Toyota wants to sell a new pack for. PriusChat seems to indicate that $4k is pretty average as they'll want to sell you the ECU as well. A re-manufactured pack goes for about $1700. A salvage pack, if you can actually find one, might be $500. But even then who knows the state it would be in and how low the cells have fallen as it sat unused.

    So the point of this thread then; I'm going to document rebuilding the hybrid battery pack and replacing the bad cells as needed.

    It's not going to be pleasant. It's going to be brutally boring at times. It's going to take near to a month to complete. But it should cost me less than $500. And 1/3 of that cost can be recouped.

    So here's how it works. You have to pull the pack out of the car first. You then test each of the 28 cells in order to see which is out of spec, marking which ones are bad. You order replacement cells. And that's where the fun starts! You pick up as many LiPo/NiMH chargers as you can afford (a charger that can do 4 cells costs about $200). It takes 3 cycles of charging/discharging to bring each cell into balance. There's 28 cells to do this to. The entire cycle takes about 1.5 days to complete. With two chargers it should take about a week to bring all the cells into balance, with the final step being that you tie all the positive and negative posts together amongts all the cells to balance them within pack. Sounds easy, but it's going to be time consuming.

    So first steps is to order the chargers and wait for them to come in. I can take the pack out of the car but there's really not much to be done with the cells until the kit comes in. So as the repair progresses I'll make updates to the thread.

    In the meantime I'm going to pray that there's not too much rain (or any snow) as I'll be riding the black bitch into work for the next month.
    TheFordFamily, Jay and xcel like this.
  2. Ophbalance

    Ophbalance Administrator Staff Member

  3. ksstathead

    ksstathead Moderator

    Sorry to hear this, oph. Best of luck; look forward to your updates.
    xcel likes this.
  4. Ophbalance

    Ophbalance Administrator Staff Member

    The real issue that it's going to take nearly a month with all the balancing of batteries and waiting on materials that's the killer. I've got heated gear to keep me warm down to freezing on the bike, and really, NC rarely gets that cold for any extended amount of time. It's the rain and lack of waterproof bags to protect the laptop that will make it more of a struggle. Plus the kids all have various activities that they participate in that will make scheduling an absolute nightmare.
    xcel likes this.
  5. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    I like the black bitch. I had a number of Honda V-Fours , and I loved 'em. All 750's. I rode the 91 VFR from Chicago to Denver in one day. I was just a boy at the time , not sure I could do it today.
  6. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    All the points for your Monty Python quote there! :D

    Sorry to hear about the car trouble. Hope it all works as planned and there aren't any unexpected hiccups on the way.
  7. Ophbalance

    Ophbalance Administrator Staff Member

    I JUST got it put back together. Again. For, I dunno, the 12th time maybe? It's a stunning machine when it's running right. But when anything at all gets into the carbs... keep a priest and a rabbi on speed dial. So far this bike has taken me from NC -> PA and back. Also out to the TN mountains and back. We have another trip to go ride the TN mountains again in April so fingers crossed and then again in July so fingers crossed!
  8. Ophbalance

    Ophbalance Administrator Staff Member

    I'd rather laugh it off than cry, ya know? There's bound to be "worse" that tries to crop up. I'm mega super annoyed that Optima changed the posts on their battery for the car (the 12v). I bought a new one and even with the lead spacers for the battery terminals are still apt to allow clamps to slip off. That battery may yet go back.
  9. S Keith

    S Keith Well-Known Member

    I missed this thread until today.

    If you're ordering Imax B6 or hitec X4, I urge you to return them.

    I do what you're doing professionally as a side business in the Phoenix area and would be happy to provide some guidance.

    You're already off to an outdated start. The "paralleling" of modules is absurdly silly. It doesn't work at all.
  10. Ophbalance

    Ophbalance Administrator Staff Member

    What would be the best charger for normalizing the modules?
  11. S Keith

    S Keith Well-Known Member

    "normalizing" is a misnomer, and I can't give you an easy answer. "normalizing" assumes all 28 modules are a reasonable performance match for one another.

    Resting voltage between modules is irrelevant. Their voltage response to assist/regen current is what matters. Resting voltage is a non-indicator of state of charge.

    If your intent is to cycle modules, and you want to do it as quickly as possible:


    This is like buying 4X HitecX4 50W or 2X HitecX4 80W or 16 Imax B6 50W or 8 Imax B6 80W in terms of discharge power. If you have the option of powering the unit with a large 12V battery, they can discharge at 20A per channel vs. 1-2A on the Hitec/Imax. If you don't use a 12V, you'll be able to discharge at about 2.8A on each Reaktor unit. You can also charge at higher current to cut that time down as well.

    You will need a 12V power supply. I use these:


    If you want to get really serious and move a lot of electrons, I can loan you some batteries that will allow you to discharge at 20A.

    If you've encountered "S Keith" on many of the reconditioning related threads on PC, that's me.

  12. Ophbalance

    Ophbalance Administrator Staff Member

    I could certainly pick up the Turnigy instead. None of the local hobby shops have anything decent (well, there's a serious lack of decent hobby shops as well) and I was looking to order something tonight so I could start next week. Do you have a recommended setting for the charge/discharge cycle? And to be clear if I use a 12v lead acid I won't need the 12v AC power supply from eBay?
  13. Ophbalance

    Ophbalance Administrator Staff Member

    The side benefit to this charger is being able to kick my dinky little 1x Prophet LiPo/NiMH charger to the curb.
  14. Ophbalance

    Ophbalance Administrator Staff Member

    Yeesh, our hobby market in the US is rather in a slump or something. You can't find that on amazon at all. Guess I'll do it from eBay.
  15. S Keith

    S Keith Well-Known Member

    You have to replenish the 12V charge, so you'll need a 12V charger capable of about 20A to charge the 12V :)

    It depends on what you want to do. If you want to monitor things and do cycles manually @20A, it's pretty manageable. If you just want hands-free cycling, just get the eBay PSU. Once you've done the cycling, you can discharge each once at 20A for a final check.

    It's a server power supply he's modified. That seller is local to me in Phx. Never met him, but he's been selling these for well over a year. Mine have been bulletproof even when abused.

    When you have ordered the QuadKore, PM me your address, and I'll send you some charge leads you can use with the QuadKore. You have to fabricate your own otherwise.
  16. Ophbalance

    Ophbalance Administrator Staff Member

    QuadKore being the eBay iCharger dealio? I'm going to order both the Turnigy and the iCharger tonight. If I don't have to use a lead acid in the mix, that'd be fantastic. But I can "liberate" some from my local drop off convenience center for our trash. They recycle them, and I'm fairly sure they'll have at least one large truck battery waiting to be re-purposed. Unless the Optima I've pulled out of the Prius would be up to the task? Though it might have gotten dead with this whole not being charged by the large pack deal.
  17. Ophbalance

    Ophbalance Administrator Staff Member

    Did you happen to do a write up of newer instructions in the gen-ii-prius-individual-battery-module-replacement thread? It's... well it's quite a lot of reading and pages to sift through, but I see you had interactions over the course of the thread.
  18. S Keith

    S Keith Well-Known Member

    That thread is a nightmare. It should die.

    Two items:
    Turnigy Reaktor QuadKore from HobbyKing
    "iCharger" 85A PSU from ebay

    Setup a Google sheet for data collection.

    QuadKore (for power by ebay 12V PSU)

    Settings screen:
    • Turn off key keep
    • Regenerative discharge is OFF
    • Internal discharge power to 300W regenerative and 20W internal
    • set to 5 beeps (not too obnoxious, or you can turn beep off)
    • Capacity Limit on: 9500mAh
    • CHG/DCH Wait: 30 minutes
    • NiMH sensitivity: 3mV
    • Safety Timer OFF (discharges will take longer than the 120 minute default)

    NiMH menu:
    • Manual charge: 13.0A
    • Discharge 3.3A to 6.0V
    • Formation Charge 6.5Ah, 6 cell
    • Cycles 5, dch>chg(man) (3 isn't enough in most cases)

    Set a fan to blow into bottom of pack (end opposite the ECU, the cavity below it). If you have a Vornado or similar small fan, directing the flow into that cavity will actually create a slight updraft.
    1. Connect to modules 1, 8, 15 and 22 (maximum spacing to ensure there are no heating issues).
    2. Go to NiMH menu
    3. Go to discharge
    4. Long press stop button: record resting voltage (Vi)
    5. Long press start button: record Internal resistance.
    6. Press stop button
    7. Long press start button to initiate 3.3A discharge to 6.0V
    8. Charger will start lower than 3.3A but slowly increase to 3.3A at end of discharge.
    9. Record capacity
    10. Wait 30 minutes after last of the 4 stop and record resting voltage.
    11. Press stop button
    12. go to Formation charge
    13. Initiate formation charge (can take 3-4 hours) - this charge helps to balance the cells within the module.
    14. Record mAh input and resting voltage at least 30 minutes after charge completes.
    15. Press stop button
    16. Go to cycles
    17. Long press start button.
    18. Check periodically. Record in and out mAh. If capacity is > 6000mAh after 3 cycles, terminate AFTER the 3rd CHARGE.
    Cycles should finish in 20 hours or less (2.5 hr discharge assuming 6500mAh, 45 minute charge, 60 minutes total wait per cycle).

    Repeat 7 times marching through the pack.
    Last edited: Feb 13, 2017
  19. Ophbalance

    Ophbalance Administrator Staff Member

    Absolutely stellar. Orders are placed. The charger gets here Weds and the PSU might get here next Friday. If I just use a multi-meter to pull the voltage without load, I should be able to determine the "bad" cell correct?
  20. S Keith

    S Keith Well-Known Member


    module = six cell battery. 28 per pack - smallest unit that can be replaced.
    cell = individual NiMH cell, 6 per module cannot be individually replaced.

    Generally, yes. After 24+ hours of sitting, one or more will be < 7.0V (6.3-ish or 6.8-ish). Note that you are looking for outliers in all of this. It's not what #s are good or bad, it's what #s are different. For personal use, a pack with 3500mAh modules in it can perform surprisingly well provided they are ALL similar in performance.

    Record your 28 modules voltages. Identify the max. Anything < (max - 0.05V) = suspect. Anything < (max - 0.10V) is very suspect. The only exceptions are the end modules. They tend to run a little lower than the rest of the pack - you may want to factor them out if that's the case. If your max is an outlier, then pick the largest group of values within .05V of each other, and those are likely your best-matched cells.

    BTW... I've done lots of experiments with paralleling modules and found crazy variations, but most of it was observational, not recorded. For comparison purposes, I selected 2X modules - one from 2007 (gen 2) and another from 2013 (gen3). I discharged both at high current to 6.0V to empty them. I then charged the 2007 module with 4000mAh of input.

    The charged module was at 8.43V and the discharged module was at 7.45V. I paralleled them together with bus bars and secured them with terminal nuts (very low resistance connection).

    Voltage equalized to 7.95V I left them that way for 2 hours. Upon disconnecting them, they were both 7.95V

    I discharged the 2013 module: 1194mAh
    I discharged the 2007 module: 2529mAh

    Note that they both had the same resting voltage, but they have wildly different capacities. Yes, the lower cap module would have dropped over time, but this is illustrative of how ineffective paralleling them is. Current flows based on voltage. NiMH voltage reacts very quickly under load or charge, and then current flow drops to nearly nothing. Resting voltage of NiMH is very sluggish.

    When one has the proper tools, one can balance MUCH better. Easy mode is to set all of them at 100% with a full charge and install in the car... :)

    I again charged the 2007 with 4000mAh input, paralleled them and will repeat the discharge tomorrow.

    TheFordFamily and BillLin like this.

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