It was supposed to be 7.48V. Its right in my datasheet.

 

Gotcha. I didn't check the datasheet.

I recommend you record those daily for a week and see how they go. Since your pack was working when it was pulled, you can probably use the voltage rebound/retention as validation of low self-discharge.

 

Would it be possible to extrapolate time to a 6V reading when on the 100Amp load tester by using the equation:

(Vstart - Vend)/30seconds = (Vstart - 6.0Volts)/Xseconds

and then plug the answer in seconds into the equation we had previously used (50Amps*seconds*.278)?

Jen

 

No. The voltage response isn't linear. The initial drop is fast followed by a semi-linear taper through most of the range with a rapid drop off at the end. Here's a sample chart:



Additionally, capacity is different at different loads, particularly at very high loads, and the associated voltage drop is higher. Any extrapolated number as you propose would produce artificially low capacities.

Steve

 

Thanks for all your help! Your knowledge and willingness to share it is great. I ordered one of those 130A power analyzers you suggested. I think that will be a big help. - Jen

 

You're welcome. I took another glance at your spreadsheet. Nothing jumped out as being a problem. Keep up the good work!

Steve

 

Steve,

I gave this reconditioned pack to a guy when it was charged and allowed to rest till it measured about 144V. The guy is getting P1435 and 1570 codes and the battery is not charging to full. This was after driving it to try to get it peaked up to SoC. I finally got him to agree to do a 12V reset and let the car idle for 30 minutes. What should I suggest next if this doesn't work. This battery didn't have an IMA light before all of this work on it. Why would it have one now?

Jen

 

How long did it take to get to 144V?

Did he have those codes before?

Did the 12V reset fix it?

theory: sticks were charged unevenly. sitting for an extended period to get to 144V exacerbated the imbalance.

Steve

 

Hi Steve,

I'm agreeing with your theory. But could it be the MCM?

The 12v reset "fixed" it and it charged to 168V in 30 minutes. But the IMA light and codes came back on driving. They were the same codes as the ones he had before.

It took about 10 days - 2 weeks to go down to 144V

He has a buddy with a 2004 HCH so he is going to swap batteries with him and report back to me in two hours. If he has the same problem with this known good battery it should rule out that it is a battery problem.

Jen

 

It could the be MCM. I don't have the service manual for the HCH1 and many of the codes are different for the HCH2.

The fact that it went off but came back on is of concern. P1570 is either a weak IMA battery or the voltages are out of balance.

You can check the Orange plug where it goes into the BCM. You don't need to unplug it. You can probe it where the wires go into the back of the connector.

The voltages are at pins:

14-6
6-13
13-5
5-4
1-7
7-2
2-8
8-3
3-9
9-10

All of those voltages should be close to each other.