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

What replacement battery to choose?

Discussion in 'Gen 3 Prius Technical Discussion' started by 4md, Oct 2, 2017.

  1. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    About every 2-3000 miles I get the "Check hybrid system" error on the dashboard with P0A7F error. I haven't check the individual cells yet, I'm pretty sure that replacing 5-6 cells will do the job, but to be honest, I think the overall battery health is not good due to the high ambient temps where the car was driven, even tho it has only 112'000 genuine miles on it (2011).

    A new battery from the local stealer is $4280, so I won't go this way. I found several whole battery packs on ebay from the UK (I live in EU, so I won't pay any VAT or taxes) and the shipping wont be more than $200. The batteries are between $1100 and $1500 but I wonder what is better option:
    one is from 2011 car with 9800 miles on it (yes, 9'800), other is from 2015 Prius with unknown miles (doubt it it woud be more than 50'000). There are few other batteries - for example one from low miles Lexus CT200H for $800 and the most interesting is from 2015 Prius Plus. Visually the battery from the Prius Plus is not the same, it's much taller and narrower than mine (I'll attach photos), but wondering if the cells are replaceable with the Prius 3 non-plugin?

    What's better in your opinion - newer battery with more miles or older with almost no miles?
     

    Attached Files:

  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    they all look good. if there is any way to get a handle on supplier reliability, i would take that one. if not, the important thing would be how long the battery has sat. for instance, if the 2011 crashed after one year, and the battery has sat for 5 years, that might not be a good thing. the 2015 certainly sounds good.
     
    4md likes this.
  3. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,596
    3,770
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    No, the answer is right there on the label in the first photo: LiOn. Different chemistry from yours which is NiMh.

    Generally speaking, newer is better.
     
    Prodigyplace and 4md like this.
  4. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    Oh my god... Thank you, didn't see that at all :mad:

    Talked to the sellers, the most interesting batteries are three, all sellers have a shooting-star ratings with 100% positive feedback:
    1. Prius 2011 with 9'800 miles on it, crashed in March this year: $1200. Don't know how such low mileage is possible tho... Honestly, I don't believe it...
    2. Prius 2012 with 67'000 miles, crashed a month ago: $870
    3. CT200H 2014 with 24'000 miles, disassembled in March: $930

    The seller of the 2015 battery wants $1700 for it and don't want to negotiate and I don't think it's worth it.

    All prices are with shipping to my doorstep and I think the third option is worth it? Tomorrow if the weather is little warmer I'll disassemble mine and will check the cells with load, but I'm considering a "new" battery from cooler climate that will be definitely more preserved than mine - maybe my fuel consumption will be better...
     
  5. MelonPrius

    MelonPrius Senior Member

    Joined:
    Apr 13, 2017
    809
    504
    0
    Location:
    Las Vegas
    Vehicle:
    2014 Prius
    Model:
    Three
    Not the 2011. I've read here that the Prius battery likes to be driven and dislikes periods of inactivity. It's averaged around 100 miles a month- good for an ICE car, not good for a Prius. And it's the most expensive option, too.
     
    Prodigyplace and 4md like this.
  6. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    Yesterday I measured the cells. The car wasn't driven, nor started for 2 days. The load I used was a headlight bulb - 12v 45w, here are the results:

    Cell | Voltage | Voltage with 10 sec load
    1 | 7.93 | 7.80
    2 | 7.91 | 7.76
    3 | 7.89 | 7.74
    4 | 7.89 | 7.74
    5 | 7.88 | 7.73
    6 | 7.86 | 7.75
    7 | 7.84 | 7.72
    8 | 7.84 | 7.72
    9 | 7.82 | 7.69
    10 | 7.79 | 7.65
    11 | 7.75 | 7.60
    12 | 7.79 | 7.66
    13 | 7.79 | 7.66
    14 | 7.80 | 7.67
    15 | 7.78 | 7.65
    16 | 7.77 | 7.63
    17 | 7.77 | 7.63
    18 | 7.77 | 7.63
    19 | 7.76 | 7.63
    20 | 7.80 | 7.66
    21 | 7.78 | 7.64
    22 | 7.83 | 7.71
    23 | 7.82 | 7.68
    24 | 7.84 | 7.73
    25 | 7.85 | 7.73
    26 | 7.88 | 7.76
    27 | 7.90 | 7.79
    28 | 7.93 | 7.82

    There wasn't a single cell with instant voltage drop and the load applied was for 10 secs on each cell. Do you think they're just unbalanced, or there are bad cells?

    The HybridAssistant app shows worse values, maybe due to the bigger current when the car is running.
    1: Just before my test with the voltmeter, the car was not started (double pressing the start/stop button without the break)
    2, 3, 4: Discharging - the car was just started and in Ready without ICE running
    5, 6: ICE running, charging

    I really don't know what to do and any advice will be helpful.
     

    Attached Files:

  7. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,286
    4,225
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    You may have to let the car sit for a week before testing for a drooping cell. Otherwise find an elm327 adapter and a copy of Torque.

    Have you ruled out the 12v battery?

    Might check for high internal resistance at this point.

    Since you have the battery apart look for (if you haven't already) corrosion in / on and around the HV battery and supporting connections, like sensor wires and bars/nuts.
     
    4md and Raytheeagle like this.
  8. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,058
    5,783
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    4md, Here's what I have for you. All the info you need is right there in the Hybrid Assistant graphs. You should also have (or get) an app called hybrid reporter. It will take that info and put it into graphs labeled HV Battery Health for easy visualization. Your very first screen capture, showing no current draw, shows a delta V of 0.291 volts. That's a bad thing. A well balanced battery will be ~0.1v or less. The battery you currently have installed is only going to get worse. As can be seen on the next two screen captures, as the battery is discharging, the delta V gets even wider, 0.320 and then 0.640. Those are really bad things. I put up some graphs on another thread where I did a discharge test of one of my recently built batteries. It was discharged from ~65% down to ~45% and took almost 9 minutes. The delta V stayed <0.1 v throughout the entire discharge. Get the Hybrid Reporter app so you can look at the graphs. It will make it very easy to see exactly which blocks are below par.

    Get the CT200H battery and then just sell yours.

    My graphs are on the below thread on post number 14.

    question on 2008 prius | PriusChat
     
    #8 TMR-JWAP, Oct 4, 2017
    Last edited: Oct 4, 2017
    4md and SFO like this.
  9. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    Thank you for your help, I really appreciate it! The forum is my source of information and almost only hope, because around here there is almost no one that wants to work with hybrids.

    Few months ago I've changed the 12v battery with regular lead-acid 44Ah, not the AGM type (like Optima). I don't think it could be the root of the problem.
    Also the copper bars had little corrosion, but I cleaned them ~3200 miles ago (post 12). The tiny cables didn't have any corrosion, but haven't check the plug on the other side, where it goes to the ECU (battery control module?), this was a mistake, I should have...

    I don't know if it's possible that the ECU has problems or it gets wrong values from the battery if there's a problem with the wiring, but probably the problem is with the battery itself and not with the wiring or ECU?

    I haven't done the test with the AC, defroster, headlights, but I was driving about 20 minutes and then stopped. Forgot to turn off the app and I was near the car, so the wifi connection was active during the whole time of ~2.5h. Here are the results from the driving. I'll do the recommended HV Battery check from the website of the app and will post it tonight.

    Thanks again for your time and help!
     

    Attached Files:

  10. Prodigyplace

    Prodigyplace Senior Member

    Joined:
    Nov 1, 2016
    11,696
    11,317
    0
    Location:
    Central Virginia
    Vehicle:
    2017 Prius
    Model:
    Two
    A regular lead-acid battery will vent fumes into the passenger area. That is not good for the health of the passengers, especially if they smoke. :eek:
     
  11. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    I'll post a photo tonight, it's connected to the original vapours tube that goes outside of the car. There are a lot of cars that have lead-acid batteries in their trunks (like Volvo), connected with ventilation tubes going outside. The tubes are just like the ones on top of the HV battery.
     
  12. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,058
    5,783
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    4md,
    I wasn't aware that you had previously disassembled the bus bars. One thing to be aware of, is that after cleaning the bars and sensor terminals the fastener needs to be correctly torqued to 48 inch pounds (5.4 nm I believe). If they are under torqued, corrosion can build up between the surfaces that should be sandwiched together. I ran into this on a previously rebuilt pack that was giving random "Block 2 becomes weak" codes, but the load tests on it were not unusual. The back of the bars where they contact the module terminal had solid black corrosion on it. They looked fine from the front before disassembly and the battery performed very well during normal driving, except when the code would just randomly pop up.

    Your symptoms are a bit unusual. The numbers on your photos are made more complicated because the car was being operated at the time with a wide range of charge/discharge values. The low voltages can be somewhat attributed to the 60+ amp discharge rates (although blocks 6 and 7 indicated voltages are whacked) and the high voltages to the charge rate, BUT, the delta V is huge. The delta of a good battery should stay relatively steady, but can spike during high current conditions. I've seen a 1.5 delta V on a very good battery, but that was during a 150 amp discharge spike. It seems crazy to me that your battery isn't giving fault codes every 5 minutes. It makes me wonder where the problem really is.

    If you are not under time constraints and have time to experiment, I would remove the bus bars again and inspect everything:
    1. If you find a problem or need to clean corrosion, I would do it and then reassemble it with proper torques. Take it on a nice drive and then run some more tests with your Hybrid Assistant.
    2. If the inspection shows everything to be in good condition, I would probably reassemble and torque it just to test it again.
    If it continues to act up, and you wanted to go the least expensive route, I would replace block 6 and 7 (or at least figure out which module is weak in each of them and replace). Then test it again.
     
    4md and SFO like this.
  13. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    TMR-JWAP,
    Thank you for your detailed explanation. I had them cleaned with sand paper very well, also I'm sure the problem is not from the tightening - they're very well tightened up, more than the specified torques. Yesterday, when I measured the modules, the bus-bars were removed and they still were absolutely clean on both sides without any corrosion on them or on the sensors' connectors. The sensors' connectors were clean even the first time.

    The battery has strange behavior indeed - most of the time the car runs great - when I remove my foot from the gas pedal, the ICE instantly shuts off, runs on EV about 0.6-1 mile with constant speed of 40-43 mph, but there are days when I can feel something is not right - ICE runs longer, sometimes does not shut off at all at stop-lights, when I'm on down hill, it still does not shut off. The only strange behavior in it's "good days" is when the ICE shuts of, few seconds after that it starts for about 2-3 seconds and then shuts off again. I don't think it's normal.

    Buying the CT200's battery is not a problem, what's worrying me is if the problem is really (in) the battery and not in some module or wiring somewhere deeper in the car. I'll even enjoy the new battery - I'll calm down and stop stalking the MFD for the charging arrows... I'm just not sure if the battery is the problem.

    I already can recognize when the error will be displayed (last time was ~3 months and ~3200 miles ago) - when I drive for at least 15 mins, the ICE does not shuts off at all, the battery level (on the MFD) is 1 bar from full, the charging arrows keep showing and disappearing for 5-10 seconds and after 5-10 minutes - the "Check hybrid system" glows with a DTC P0A7F. I think (at least that's how it looks for me) the car tries to balance the modules with charge-discharge cycles, then it sees the difference in the voltages and shows the error. I also have the Techstream diagnostics, but it shows the same voltages as the Hybrid Assistant.

    I'm attaching two tests. The first one didn't shut down the ICE at the end, I had it stopped with the start-stop button - it started to behave just like when the error will be shown. The second test is interesting with huge voltage drops and delta-voltage pikes. It was shorter, but with interesting/strange graphics.

    BTW, on the label of my battery, the part number is G9280-47080; Panasonic EV Energy Co. but the CT200's says: G9280-76010; Primearth EV Energy Co. I found that they're exchangeable, but just mentioning if there's some sort of catch in that :)

    EDIT: Oh, totally forgot to take a photo of the 12v battery's vapor hose, sorry. Tomorrow will post one.

    EDIT 2: According to Hybrid Assistant, which is the first block - the one next to the fan or at the other side? I found a lot questions about that, but the answers were different - mainly due to which Prius generation is diagnosed. My list with voltages starts from the other side and module 28 is the one next to the fan.
     

    Attached Files:

    #13 4md, Oct 4, 2017
    Last edited: Oct 4, 2017
    SFO likes this.
  14. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,058
    5,783
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    P0A7F= "Hybrid Battery Pack Deterioration".... 2 listed causes. One is the HV battery Assembly, the other is the Battery ECU. Install the CT200 battery and that eliminates both. Regardless, blocks 6 and 7 are NFG.

    It is the same battery, Panasonic did some corporate mumbo-jumbo a few years back and became Primearth.

    Gen2.....block 1 is furthest from the computer end, closest to the fan.
     
    4md likes this.
  15. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    Well, I bought it for £550 which is around $720. And the postage will be around $75. After about 2-3 weeks it will be here and I'll report back its condition and how it performs, I hope I wasn't cheated :) I think to clean the bus-bars before installation.
     
    bisco likes this.
  16. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    Sorry for the late reply, Prodigyplace. Here are the photos, posted them in another thread about the 12v battery condition: Voltage readings.
     
  17. 4md

    4md Member

    Joined:
    Jun 9, 2017
    97
    55
    1
    Location:
    Sofia, BG
    Vehicle:
    2011 Prius
    Model:
    N/A
    The battery from CT200h came on Wednesday and it was on pallet :LOL: I hardly fit it in the back, the guys at the courier office laughed a lot :ROFLMAO: The battery is with everything that was in the car - all relays, modules, even with the keyless antenna. It was dusty, so I had it disassembled to clean it properly, oil the fan and measure the modules. Every single one of them was reading 7.58v without load and 7.49v with 55w bulb after 10 seconds, must be a good sign since it wasn't used since the end of March?

    It's very interesting, that the CT200h does not have the rubber hose for the battery vapors, so I used mine. The plastic cap at the end also didn't have the holes for the hoses.

    The bus bars were in much worse condition than mine... I soaked them in phosphorous acid, cleaned them and after that - soaked again in acid from old 12v battery. They look like new now.

    Yesterday I replaced it and start the car. The first thing that I noticed was the slower charging of the battery. Not by much, but it definitely needed more time with ICE running. Impatiently assembled everything and went for a drive (~60miles). The car runs great, the battery lasts longer in EV mode.

    Before the drive, I did the test from the Hybrid Assistant. Do you think this results are ok? o_O The battery wasn't used for few months, I'll do the test again after some driving to compare it with the one from yesterday.
     

    Attached Files:

    bisco and SFO like this.
  18. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    impressive!(y)