Update, all cells have been completed. Bold rows somehow got the DSC-CHG pattern reversed....

Voltage tests on them all as they sit (not all of them have hit 30 day mark, max days past is 21 days) are all within spec. Delta .19V. Very close to spec, but within.

Well I shouldn't say all. All but one pack. A mischevious C3-C4 pack. That has been sitting since 3.20.2017. That is at 15.71v, the rest are all between 16.01v and 15.82v.

I put that C3 pack back on for another round of discharge, formation, 8 rounds, and formation again to see if I can get any further on it. Might as well keep my setup running for another minute.

And the pack that just finished charging a few minutes ago is still up at 16.5v. I don't count that.

Once that settles out and the C3 pack finished. I think I am going to re-assembly the pack and throw it in. I have meh hopes for this. At minimum I hope it allows the 12v to charge. As far as longevity, I'm fine with grid charging it often, hopefully preventing the issue from re-curring.

Though, if it doesn't fix the issue, I may have to get my eyes on ebay and see if I can find a new DC/DC converter and other misc parts to test with.

Cheers S Keith for getting me this far. Without you sir, I would be lost.

 

They could be better, but I've seen far worse. Even if they end up being, meh, once in operation, they shouldn't inhibit charging due to voltage disparity.

15.71 likely has 1-2 marginal cells that have bled of the bulk of their capacity but still have decent voltage.

The proof in the post-wait-discharge-pudding. AFter waiting a consistent period on each stick, they should all have pretty consistent discharge capacities. Outliers will screw you.

 

So I had some free time today and decided that I wanted to do some wrenching. I know I shouldn't have and should've waited to check bleed off voltages but oh well.

Installed battery. Started car up. 12v light was off for about 5 seconds and popped on followed by an ima light. P07af. Same spot I was in before. Wtf.

Pack was at 175v when installed and after a couple charge cycles I was at 179 to 180v.

I'm looking up the tap voltages pin out to see where my voltages are.

Any ideas, S Keith? I'm stumped minus replacing bcm and inverter assembly or replacing battery pack... and I'm not going to do replace the pack. I'll pony it off on CL before I do that.

 

If your taps come in fairly close, I'm stumped. Do you have the service manual?

 

Taps came in very close except for two sticks. The two sticks that I have just finished charging. I never took a final voltage reading so that kind of makes sense. 17v and 16.7v outliers with 16 to 16.2v average across the rest.

I wonder if I should pull the pack and the connections between subpacks and let those two settle down. They've only been off formation charge for ~8 hours.

And no I do not have and service manual.

Also my SOC gauge is all over the place... that is a new one. It keeps fluctuating slowly between 1 bar and 8 bars. Stopping randomly at 2 3 5 bars.

My assist and charge are completely disabled now as well.

 

Okay, that's a **** show.


Did you charge them at significantly different times? Essentially, before you put a pack together, you need to top them all off. If some of those have sat for days/weeks since charging, that's bad. Usually the low taps will pop up and narrow that gap to a workable range, but not always.


The 1V disparity is telling the computer that you have a completely failed cell, which likely isn't true. When trying to assess SoC, the car is seeing the high tap indicate full and the low tap indicate empty, so it's oscillating back and forth.


As a shortcut to charging them all individually - just to see if you can get some idea of if it's working or not, have you disconnected the 12V and reconnected to conduct an idle charge?


Disconnect 12V for 30 seconds
Reconnect 12V
start and let idle until the IMA battery stops charging - no revving, no driving.
Repeat 3 times.


The best solution to get rid of this issue is to individually top-off the subpacks.

 

Yes I cycled 5 times pulling 12v cables. I have the pack pulled and am bringing it back home for top offs

 

Update: after battery top offs and sitting for approx 45 hours pack was installed. Tap voltages all within 16.14 to 16.21. No IMA light. Charge and assist are enabled. Pack standing voltage was approx 177 volts and is now 184 with a chare cycle under its belt. No 12v charging though.

It's got to be something else causing the issue now. Going to charge the 12v and take it for a drive furthe than the .5 of a mile I can accomplish in my small neighborhood to see if anything changes.

 

Well, I think it's safe to say the pack isn't the problem if you have normal assist/regen.


I would definitely look to the MCM and DC-DC converter. The manual indicates a bunch of checks for voltage and resistance on MCM pins.

 

S Keith,

Do you have access to a service manual? Can you pass any info along that is contained in it before I buy one?