IMA Battery Pack

Discussion in 'Honda Hybrids' started by HCH2007, Mar 20, 2013.

  1. HCH2007

    HCH2007 Journeyman Hypermiler

    Well, Eric you are right. I forgot my basic Ohm;s law i.e. adding cells together to achieve higher voltage results in an increased resistance not current. The cost of new is higher then my wife wanted to spend, so I got the used pack and paid only $1300 for it. I have eBay and PayPal buyer protection on the deal, so if this is a scam I will get my money back. We will have to wait and see....

    Eric and Herm thank you for all the input on this subject, I have been out of the loop for awhile while in Afghanistan for a year as a civilian contractor. Again thank you for all your help.
     
  2. ericbecky

    ericbecky Member

    Glad to help.

    One thing about the used pack, if you have questions about reconditioning, I'd be glad to point you in the right direction.

    Do you already have a charger in mind you are thinking about using? Or do you plan on building one?
     
  3. HCH2007

    HCH2007 Journeyman Hypermiler

  4. ericbecky

    ericbecky Member

    It's not what I use, but following those instructions will be fine and not damage the cells.

    One thing that is missing is a long soaking charge when you are done with all the cells. But given that you'll be working with single sticks and the soak would be an extra day per stick, I doubt most people would do that.

    For a baselline it would be good if you kept a spreadsheet that recorded info about the sticks regarding the cycle data. ah in, ah out, etc
     
  5. HCH2007

    HCH2007 Journeyman Hypermiler

    Could the long soaking charge be performed after the pack is reassembled? The spreed sheet is a good idea to do. Do you have one already set up that you would share? Also, what method do you use, is it any quicker or more efficient?
     
  6. ericbecky

    ericbecky Member

    Sure, I can send you a spreadsheet. Pm me where to send it.

    You'll mainly be limited by your charger choice.The one in the article has a max discharge rate of only 1amp. Charge is limited to 5amps.

    Other chargers can do much higher amounts and have more features, but they cost more. A few hundred dollars compared to less than $40 for a basic charger.
     
  7. HCH2007

    HCH2007 Journeyman Hypermiler

    Eric, do you have a link to a procedure to do the IMA pack dismantle for a 2007 Civic? There is quite a bit of difference between the earlier battery pack and mine.

    Thank you, Wayne
     
  8. ericbecky

    ericbecky Member

    Rebuilding a HCH pack like yours is quite a bit different and definitely more tricky that the earlier packs. That's also why few people sell replacement packs for these generation Civics other than me.

    Since I mainly do it myself for customers at our shop I have never really documented it. I just jump in an do it. :)

    In general with any battery removal, go slow and carefully and look out for small sensor wires as you dismantle and especially when pulling out the sticks.

    Turning off the breaker decreases the pack voltage by about half, but it is still high and dangerous.

    Wrap your tools so that the minimal amount of metal is exposed, and when possible, use plastic tools (ie a plastic prybar if pulling off the endcap.) and cover things up when now working on it. Nothing worse than a pet who climbs up on the workbench, or a spilled soda from a curious kid.
     
  9. HCH2007

    HCH2007 Journeyman Hypermiler

    Eric, Would you be willing to sell new sticks for any bad ones I might have? I will pay in advance and for the shipping also. When the replacement pack came in I checked voltage and it was 0 VDC. I checked it where the leads hook up, is there any other place that I should be checking?

    I hope I am not being a pain, I really appreciate all your help and input, I am an electrician by trade and will be very careful with everything while working on the pack. I tend to be the kind of man who learns everything he can about fixing the thinga I own.

    Thank you, Wayne
     
  10. ericbecky

    ericbecky Member

    I'll do what I can to help out and can definitely sell you some sticks from my inventory.

    0vdc is unlikely, but if it really is, then that would not be good. Where are you checking the voltage?

    For those who are comfortable doing it, fixing things on your own is good.
     
  11. HCH2007

    HCH2007 Journeyman Hypermiler

    I checked the voltage at the connection point for the power output, with the breaker on or off it read 0 VDC. I read some where on another forum about a relay and that you would only get a proper reading if you took the reading before the relay. I am checking it out to see if I can locate it. Not sure where it may be on the board.
     
  12. ericbecky

    ericbecky Member

    You will not have voltage at the top connections. Too much other electronics that aren't hooked up. You need to get on the actual ends of the pack. With the pack out of the car the top connections will not be energized even with the switch in the "on" position.
     
    Last edited: Apr 4, 2013
  13. herm

    herm Well-Known Member

    just ship that pack to Eric before you get a permanent afro
     
  14. HCH2007

    HCH2007 Journeyman Hypermiler

    That would be nice but my wife was not happy about the $1300 I spent on the used pack. So, I must recondition it myself.
     
  15. ericbecky

    ericbecky Member

    $1,300 is about half the cost of a new one installed, so you are doing just fine.
    You'll eventually get the job done.

    Just saw a 2009 in with a bad pack. I expect we'll be seeing more of these.
    He was past the mileage portion of the warranty.
     
  16. HCH2007

    HCH2007 Journeyman Hypermiler

    Well, the pack is dismantled without any "shocking"experiences. I used my voice recorder and camera to make detailed notes and a record of the process. I had one stick at 6.7 volts and 2 at 6.9, the rest were all 7 volts or higher 4 or 5 were 7.5 and one was 7.7. Still waiting to receive the charger via UPS ground. soon as it gets here I can get started with the real business at hand. I will keep you posted.
     
  17. herm

    herm Well-Known Member

    7 cells per stick?.. can you measure somehow the voltage on each cell?.. you might have to puncture the insulation if there is any..
     
  18. HCH2007

    HCH2007 Journeyman Hypermiler

    I believe there are only 6 cells per stick from the looks of the stick construction, length, etc.
     
  19. herm

    herm Well-Known Member

    7.7V out of a 6 cell stick is hard, unless its fresh off the charger or your meter is not too good.
     
  20. HCH2007

    HCH2007 Journeyman Hypermiler

    Eric, I am wondering. Since the biggest detriment to the Honda battery pack is heat, would there be any reason I can't eliminate the Styrofoam packing Honda puts on the packs. I reassembled the frame without the foam and it is very sturdy. I had already intended to add a fan to help cool the pack, but it seems if the foam was removed it will allow a lot of heat to escape and keep the battery cooler better, too.
     

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