HCH Battery is dying :(

[Jdesign]

Originally Posted by S Keith

Battery temperature is what matters. 24 hours is not sufficient. I'd give it another 8 hours per my recommendation above.

After another 8 hours, I'd drive it and see what happens. Given the method of discharge, subsequent cycles will only give small improvements if any. If the pack codes or recalibrates regularly, it's done.

Concerning stick replacement, I think you've likely done too little research again. Stick replacement is not a trivial exercise. Sure, the act of physically replacing a stick is relatively simple and time consuming. However, getting a lasting repair is extremely difficult. If you're cool with whack-a-mole and getting into the pack half a dozen times before it's semi-reliable, then you should be fine.

No matter what, you're looking at grid charging as preventative maintenance moving forward.

If your time has any value, you would be better served by pack replacement.

Thanks! I appreciate your input!

I am sure I might be missing some things, but I enjoy learning. From what I have read/watched on youtube and other sources, it looks like you deep cycle each stick and get a final read out of data per each stick. From there replace those that show weak values if need be, or try your best to get them up to par. Let them rest and see if they hold a charge. When thats complete, re-position them in the pack so that the ones that were having a bit more time/issue taking to a normal value are on the outside of the pack. I understand that its a time consuming process.

I know its not as straight forward as just swapping sticks. I have yet to get that far so for right now this is my step 1. I agree that this is just preventative maintenance but isn't the whole situation? I mean the battery isn't going to last forever.

[S Keith]

Originally Posted by Jdesign

Thanks! I appreciate your input!

I am sure I might be missing some things, but I enjoy learning. From what I have read/watched on youtube and other sources, it looks like you deep cycle each stick and get a final read out of data per each stick. From there replace those that show weak values if need be, or try your best to get them up to par. Let them rest and see if they hold a charge. When thats complete, re-position them in the pack so that the ones that were having a bit more time/issue taking to a normal value are on the outside of the pack. I understand that its a time consuming process.

I know its not as straight forward as just swapping sticks. I have yet to get that far so for right now this is my step 1. I agree that this is just preventative maintenance but isn't the whole situation? I mean the battery isn't going to last forever.

I have yet to find a YouTube video that provides a reliable process. What they lack is:

1) use of proper equipment.
2) use of proper process.
3) identification of acceptable performance criteria
4) reliable mid to long-term feedback on success
5) reliable source for good replacement sticks

Pack-level charge/discharge reconditioning is 99.9% as effective as single stick cycling when done correctly.

If this is something you wish to devote a solid 2-3 weeks of downtime, then I can walk you through a decent process. You will likely need to purchase a salvage yard pack or source an entire pack's worth of sticks. Note that MANY folks have failed to build a working pack even when using 2-3 source packs. While the HCH2 is MUCH worse, it took me 15 packs to build 3.

With any luck, you haven't damaged anything, and what you've done has successfully reconditioned/rebalanced the pack, and you'll get some longevity out of it with grid charging and occasional discharging.

BTW... how did you discharge the pack? Did you make alternate connections? IIRC, the MV harness has a diode in it that prevents pack discharge through the harness.

[Jdesign]

Originally Posted by S Keith

I have yet to find a YouTube video that provides a reliable process. What they lack is:

1) use of proper equipment.
2) use of proper process.
3) identification of acceptable performance criteria
4) reliable mid to long-term feedback on success
5) reliable source for good replacement sticks

Pack-level charge/discharge reconditioning is 99.9% as effective as single stick cycling when done correctly.

If this is something you wish to devote a solid 2-3 weeks of downtime, then I can walk you through a decent process. You will likely need to purchase a salvage yard pack or source an entire pack's worth of sticks. Note that MANY folks have failed to build a working pack even when using 2-3 source packs. While the HCH2 is MUCH worse, it took me 15 packs to build 3.

With any luck, you haven't damaged anything, and what you've done has successfully reconditioned/rebalanced the pack, and you'll get some longevity out of it with grid charging and occasional discharging.

BTW... how did you discharge the pack? Did you make alternate connections? IIRC, the MV harness has a diode in it that prevents pack discharge through the harness.

I dont mind the down time as I have other vehicles to drive. Im curious to see how it drives as it has been on the grid charger for almost two days now.

I attached a porcelain light fixture to the same leads as the grid charger, and let the battery discharge with a 75w bulb. Probably not the best way to do it, now that I am more aware that the slower the discharge the better. Im learning though. After that I just removed the bulb and started the grid charger.

I was considering buying a pack of sticks on ebay if this doesnt help give the battery a little more "life"

[S Keith]

Originally Posted by Jdesign

I dont mind the down time as I have other vehicles to drive. Im curious to see how it drives as it has been on the grid charger for almost two days now.

I attached a porcelain light fixture to the same leads as the grid charger, and let the battery discharge with a 75w bulb. Probably not the best way to do it, now that I am more aware that the slower the discharge the better. Im learning though. After that I just removed the bulb and started the grid charger.

I was considering buying a pack of sticks on ebay if this doesnt help give the battery a little more "life"

I would not exceed much past 36 hours. Once voltage fails to rise more than 1V in 5-8 hours, the battery is full.

Ah, so you opened the IPU and bypassed the harness altogether. That's what I would expect.

I've seen it done (by me) with 200W to near 0, and that's bad. 75W is only .68A at 110V. At 55V, it was only about .48A.

Those are actually reasonable currents. Due to the potential to pop bulbs running that at well above 110V, I do 2 in series. I use 2X 200W above 144V and 2X 25-40W below 144V. I also limit the TIME spent below 144V to about 9 hours or the time necessary to extract about 1400mAh BELOW 144V (note that the transition from 200W to 25-40W causes a voltage bounce. The clock doesn't start until the pack goes back below 144V). I also use a harbor freight multimeter in 10A mode in series to monitor current. With time and current data, you can compute pack capacity and demonstrate improvements between cycles if they happen.

Bumblebee frequently sells boxes of untested sticks (pulled from returned cores). it's a complete crapshoot. You can get packs with tons of good sticks and packs with none. Unfortunately, you never know which it will be, and you have to test all 20 to find out. Buying a whole pack's worth makes it easier to conduct grid charges/discharges though.

I would hold off and see what happens.

The only concern I have is that you were only at 150v after several hours of charging. However, that may be a non-issue since the MV system is not designed for discharging, it's operating voltage MAY not permit much charging at low voltages, so it's possible very little charging occurred during the initial hours. The HA chargers "pulse" at low voltages as the various power supplies in it actually output greater than the .35A CC supply. This helps bring them up faster from lower voltages.

If the MV charger was pushing the full 300mA for 8 hours, and you were only at 150V, something is likely wrong.

Lastly, after you disconnect the charger, let the pack sit overnight (10+ hours) and then check the 10 tap voltages to XX.XX accuracy. Take the car for a test drive, allow it to sit form 10+ hours and check them again. Those are the most readily accessible way to see if you have issues inside the pack.

[Jdesign]

Originally Posted by S Keith

Lastly, after you disconnect the charger, let the pack sit overnight (10+ hours) and then check the 10 tap voltages to XX.XX accuracy. Take the car for a test drive, allow it to sit form 10+ hours and check them again. Those are the most readily accessible way to see if you have issues inside the pack.

All VERY VERY good information. Thank you again!

The only part I don't understand is the 10 tap voltages. What do you mean by that?

Also the Battery was at 171-173?(I don't remember exactly) when I checked it last night as it was still on the grid charger. I will go at lunch, record the number, remove the grid charger, and let the pack rest for a day, then check the numbers again before driving.

[S Keith]

So, you've dropped from 178V to 171-173 during the same charge with no change in ambient temperature?

Access the pack fan exhaust behind the passenger side trunk lining. It should be no more than slightly warm.

In any case, I would terminate charge. A drop that low is indicative of inadequate cooling and/or cell failure.

There is a 14 pin (or so) yellow connector between the orange cable coming from the battery to the MCM. You can probe that connector without unplugging it and measure 10 stick pairs. If there is significant deviation in those voltages, you can conclude you have a failed pack.

BTW... Did you have a P1433 IMA fault?

[Jdesign]

Originally Posted by S Keith

So, you've dropped from 178V to 171-173 during the same charge with no change in ambient temperature?

Access the pack fan exhaust behind the passenger side trunk lining. It should be no more than slightly warm.

In any case, I would terminate charge. A drop that low is indicative of inadequate cooling and/or cell failure.

There is a 14 pin (or so) yellow connector between the orange cable coming from the battery to the MCM. You can probe that connector without unplugging it and measure 10 stick pairs. If there is significant deviation in those voltages, you can conclude you have a failed pack.

BTW... Did you have a P1433 IMA fault?

The "171" was a guess. I am on my way to check and confirm my final number.

As far as the connector, I can assume that positive voltage is present and I can just use the ohmmeter between the packs negative terminal and each pin to record my findings?

Yes I did have a IMA fault code, I have for a few months, I just havent had time to dig into the battery like I am now.

[S Keith]

Originally Posted by Jdesign

The "171" was a guess. I am on my way to check and confirm my final number.

As far as the connector, I can assume that positive voltage is present and I can just use the ohmmeter between the packs negative terminal and each pin to record my findings?

Yes I did have a IMA fault code, I have for a few months, I just havent had time to dig into the battery like I am now.

No. There is a lead to each stick pair, i.e., you just walk the probe from one set of pins to the next. When I can access my dropbox, I'll send you a diagram of the pins.

Codes matter. P1433 or other?

[Jdesign]

Originally Posted by S Keith

No. There is a lead to each stick pair, i.e., you just walk the probe from one set of pins to the next. When I can access my dropbox, I'll send you a diagram of the pins.

Codes matter. P1433 or other?

Checked on the car- Battery is now down to 169. I unplugged the charger. I can run codes tonight after Im off of work.

Diagrams would be awesome. Thank you! I appreciate your input very much.

[S Keith]

I find that very concerning. Are you 100% certain the battery fan is being driven?

Are you doing the charging with the IPU lid closed or open?

https://www.dropbox.com/s/k9tgm6qvl2...ector.jpg?dl=0

14-6
6-13
13-4
4-12
1-7
7-2
2-8
8-3
3-9
9-10