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Preventive maintenance on HV Battery (replacement)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by JC91006, Jun 19, 2014.

  1. JC91006

    JC91006 Senior Member

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    I went and got myself a new(er) 2012 GenII battery today from a car that broke down (bad transaxle) with 400,000 miles. The battery was newly purchased in 2012 from Toyota. I want to install this in my 2005 which has the original HV battery from the factory. Although it's still working, I just want to do some preventive maintenance here.

    My questions that I have are:

    1. The new(er) battery has sat for about a month and only shows 1 bar on the MFD SOC when I removed it from the car. Do I have to charge this battery before installing?
    2. My 2005's battery is still good, do I have to worry about it going bad if I let it sit after removing it? I do plan to sell this battery on since this is currently a working battery with no issues.

    Thank you all for reading this......
     
    #1 JC91006, Jun 19, 2014
  2. Prius_Cub

    Prius_Cub Member

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    At one bar, the new battery is close to 40% charged. IIRC, the battery can still start the engine with something like a 20-25% SOC.

    For your 2005 battery, if keeping it long term, you could reassemble the modules in parallel and take a hobby charger like one of the Supermate DC6's, iMax B6, etc and top it up every now and then (not all the way of course), then cycle the modules before putting it back into service/selling it.

    For the life of me I can't find the thread that addressed long term storage of a spare pack.
     
    #2 Prius_Cub, Jun 19, 2014
  3. NR427

    NR427 Member

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    Why replace a battery that is still good?
     
    #3 NR427, Jun 19, 2014
  4. JC91006

    JC91006 Senior Member

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    I have this fear of getting stranded when I leave on a roadtrip. Doing this swap now with a newer 2012 battery gives me the peace of mind to travel worry free with a lesser chance of battery failure when I'm out of town.

    SM-N900P ?
     
    #4 JC91006, Jun 19, 2014
    Last edited: Jun 19, 2014
  5. JC91006

    JC91006 Senior Member

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    I was reading another thread just this week that mentioned the owner left their car sitting for 2 weeks or a month and the HV battery got a weak module. Although I believe the module was already weak, I just don't want this scenario to happen with my 2005 battery. It works perfectly since it's driven daily, but what if I take it offline for a month?
     
    #5 JC91006, Jun 19, 2014
  6. nh7o

    nh7o Off grid since 1980

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    As batteries age, the self discharge rate increases. That would say that letting a battery sit for long periods will tend to increase the imbalance between the modules. Keeping the modules paralleled and periodically charged sounds like a good idea.
     
    #6 nh7o, Jun 19, 2014
  7. The Electric Me

    The Electric Me Go Speed Go!

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    I have no experience doing what you are planning to do, however my uneducated guess would be you would be fine putting the new battery in, even if it was reading only one line of charge at removal from the donor vehicle. If I'm wrong? You'll find out pretty quickly once you install the new one. But I see no reason why your Prius couldn't charge a perfectly healthy HV battery up from 1 line of charge.

    As far as storage of your removed "older" battery?
    Once I was confident in the operation of the newer installed replacement, I would as quickly as possible sell the old one. I would simply plan to not let it sit very long. If you are talking 4 weeks or less, again my uneducated guess would be you wouldn't have a problem.

    I would sell it with full honest disclosure and as a "as is" product. Then any potential problems, become the responsibility of the buyer, who would be purchasing with full knowledge of the situation. If you sell it to someone who salvages batteries, they'll know what they are getting and what to do with it.
     
    #7 The Electric Me, Jun 19, 2014
  8. JC91006

    JC91006 Senior Member

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    I'm taking it apart now and I notice something really strange, the replacement newer battery has a bunch of Chinese/Japanese stickers on it, the original battery only has an English label on it. Even the part numbers are different.

    From 2005 - newer purchased in 2012 replacement part #g9510-47031
    Old 2005 battery part #g9280-47100
    [​IMG]
    [​IMG]
     
    #8 JC91006, Jun 19, 2014
    Last edited: Jun 19, 2014
  9. jdenenberg

    jdenenberg EE Professor

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    Your two batteries are NOT interchangeable. You can use the 2012 modules to replace the modules in your 2005 battery, but I would balance each of the 28 modules, load test each to determine voltage drop (pair them up sop the total drop is the same across the 14 pairs), and equalize them (module voltages the same ) first.

    JeffD
     
    #9 jdenenberg, Jun 19, 2014
  10. ericbecky

    ericbecky Hybrid Battery Hero

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    As mentioned above you can't directly swap the 2010 battery into your 2005.
    They have different part numbers because they are different parts.

    I would not bother putting the 2005 modues back into the 2010 and sell it.
    It would be way too "frankenstein" of a pack.
    No 2010 owner is going to want a pack with 2005 modules in it.

    Do you have battery testing equipment?
    If so go through and test the 2005 modules.
    Using the results to rate/sort the modules before storing them.
     
    #10 ericbecky, Jun 19, 2014
  11. JC91006

    JC91006 Senior Member

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    You might have misunderstood what I meant. The car it came from is a 2005 with 400000 miles. The car had the battery replaced and worked for 2 years (since 2012). Just now, transaxle failed and I purchased the battery.

    I have it installed now but I hear a clicking noise whenever it starts....like it clicks to boot up. I've never heard this battery with all the seats removed, maybe that click was there before and I didn't know about it?
     
    #11 JC91006, Jun 19, 2014
  12. JC91006

    JC91006 Senior Member

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    I don't have testing equipment. I'm not removing any of the modules....this is like getting a good battery shipped to you and swapping it in. Nothing more.
     
    #12 JC91006, Jun 19, 2014
  13. JC91006

    JC91006 Senior Member

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    All done. Wow that was more difficult than I had thought. I had a tough time putting back the plastic vent going from the fan. Spent 30 minutes trying to push that thing in place. I must've been doing it wrong, it came out like butter but was a B**ch to put back.

    Strange thing about the 2 different part numbers, the newer part number is available to purchase.....but the original one from the car, part G9280-47100 is not searchable in the Toyota parts catalog.

    I did open up the case to take a quick peek, noticed the original batteries have a serial number on each module, they are all in numerical order. I guess you can tell if you have a refurbished battery if those numbers are not in order.
     
    #13 JC91006, Jun 19, 2014
    Last edited: Jun 19, 2014
  14. nh7o

    nh7o Off grid since 1980

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    That would be the three relays that are closed at start up time, inside the battery case. There is series resistance in line to allow the battery to initially charge the large capacitors in the inverter at a slower rate. Once those are charged up, then the resistance is switched out and the battery has a direct connection.
     
    #14 nh7o, Jun 19, 2014
    JC91006 likes this.
  15. JC91006

    JC91006 Senior Member

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    One thing I did notice from the 2 year old battery I bought, when I opened up the case, there was lots of clumped up lint like material around the modules. I think the person that had the 400k mile car had a really dirty fan and it kept blowing lint into the battery case. His 2005 battery quit in 2012, only 7 years of service, might have overheated and module went bad.

    I'm thinking the people that find their battery fan and duct work really dirty, they should have a service to open up the battery and get all the crap that's built up in there. Cleaning the fan and duct work won't do much if it has already blown tons of lint like material to heat up the modules into the battery case.

    Question for the battery rebuilders that are reading this, does this seem like it occurs often when you open up the cases when you rebuild?
     
    #15 JC91006, Jun 20, 2014
  16. JC91006

    JC91006 Senior Member

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    I've driven on this battey for a week now and I seem to not get as good of gas mileage as my old battery pack. Does the battery ECU have anything to do with fuel economy?

    The battery seems to work perfectly, not sure why I would lose 4mpg with this new pack.
     
    #16 JC91006, Jun 27, 2014
  17. JC91006

    JC91006 Senior Member

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    After an entire month of running on this new battery, it still doesn't offer as good of MPG as the original battery. I do notice that the car does not charge up to green bars as easily now. Maybe the battery is newer and the cells are stronger, but definitely not seeing as much green bars as before. It's always at the top of the blue bars.

    Would an older battery offer better gas mileage because it's showing a "full charge (green bars)" more easily than a newer battery that doesn't charge up as quickly? Like an old laptop battery would charge fully in 1 hour vs a new laptop battery would take 2.5 hours to charge fully?
     
    #17 JC91006, Jul 21, 2014
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