I have a vigorous disregard for safety. I wouldn't hesitate to leave everything running. I routinely leave things running overnight and during the day while I'm gone.

 

hahaha copy that.

started at 1435ish at 166ish
ended at 0010 at 174.55

left the fan running 15minutes after ceasing charge operation.
will see how it looks in 8 hours.

I'm very curious to see where capacity calc ends up on the first discharge tomorrow.

 

10 hours? 20 more to go!

 

....all of yesterday was a waste?

I'm right back at 165.5V ten hours later....

Does this offer any hints?
well as I'm watching it's climbing faster than yesterday... back to charting...

 

NiMH resting voltage is an extremely poor indicator of SoC. What you're seeing is normal and is neither an indicator of a problem or a lack thereof.

JUST PRIOR to terminating the grid charge at 30 hours, I recommend you measure and record the 10 voltage taps (monitored every 12 cells) while still being charged:

https://www.greenhybrid.com/forums/f...03/#post259837

It's a little tricky when the plug isn't in the BCM, but it's doable. You're probing from the back side of the connector, i.e., the side the cables go into the connector, not the side that actually plugs into the BCM.

The tap data will give you more insight into issues and where you can find them.

I also recommend that you capture a second tap voltages reading at or near 144V under very light load (2X 40W bulbs or less).

 

I see that, his resting volts appeared great but he had more problems than I got!
do you know if he ever solved it?

my thinking was isn't 1433 that the car estimates that the pack has less than 10 percent usable capacity left?
if my grid charge only rehab another 10percent, (and it's got 90 to pull that from!) Then I can get it working more acceptably and predictably again.

there was one time a couple weeks ago, I stepped on it and actually got tossed back in the seat!
Don't need that every time, just need more than nothing.

problem is today is the last day i got to play with this.

 

I don't know beyond that thread what happened. I was just looking for one of the dozens of posts where I link that data...


I can't say on the code. I don't have an HCH1 manual, but P1433 is the primary battery failure code. It can be from a failed cell and/or imbalance. IIRC, there is a second code for tap imbalance, but those aren't reliable on any model of IMA. More often then not, you go straight from "works fine" to failure code with nothing in between.


That extra 13hp or whatever and it's instant torque can make a significant difference, especially at low speed/low rpm. It's especially noticeable when it's not working great, but you happen to catch it at a high SoC when you goose it.


Since you're time limited, for the future, I recommend you get a 8-10A/12V PSU from Amazon (typically about $18). Make yourself a little harness that shorts the PWM wire to fan negative and provides 12V to the fan when you connect it. This will drive the fan at full speed (leaf blower). You will be able to do everything with the pack in-car.


How much time to you have to mess with this? We may want to optimize things according to the time available.

 

Bearing that in mind, the pack had sat at 174.5 for the better part of an hour. So ill keep the fan in it for a half hour then begin draining with my two 90 watt bulbs and see where I end up... I'll get always one half arsed cycle in... might run to lowes and see if i cant get a pair of 150s

I just took too **** long getting started.

I can devote another 12 hours today for certain.
Monday I should have from 9am to 130pm (I'll need to reinstall during this time also, but don't think that's too hard now.)

 

Alrighty.
the drain has begun!

150pm. Began at 169v and 610mA

 

Been in meetings. Cutting the charge this short isn't how I would have chosen to proceed.


Do not change bulbs. Stick with what you have. for future reference, there is no need to let the pack sit before discharge. You can keep the fan running, but it will still cool during discharge. The fan is not necessary once the pack has cooled to ambient.


We need to kinda throw a few things out the window. Proceed as follows.


Note current and time at 144V. Average the current at 144V and 610mA and multiply it times the number of hours. This is your computed capacity to nominal. Note that under that low of a current, you will consume most of the available capacity by the time you hit 144V.


Take that computed capacity and divide it by two. THAT is your limit on how much more you can extract from the battery, NOT a given target voltage.


For example:


144V current is 590mA. Your average is 600mA. It takes you 5 hours to get there.


That comes out to 3Ah.


50% of that is 1.5Ah - do not extract more than this while the pack is below 144V.


You KNOW that as the voltage drops, your current will drop, so you'll never pull more than 590mA below 144V. You can then estimate a minimum discharge time of 1.5Ah/0.59A = 2.5 hours.


You don't even need to check it for 2.5 hours.


At 2.5 hours, check discharge and record voltage/current. You can then average the current again and compute extracted capacity. Subtract that capacity from the 1.5Ah, and you have a new number from which to compute the next segment of the discharge until you hit the 1.5Ah limit.


In short, you don't want to extract more than 50% of the computed capacity at 144V. At > 150% is where the damage occurs, i.e., on the 3Ah battery, the risk of damage goes way up once you've extracted a total of 4.5Ah.


Depending on timing, no matter what, you need to allow for 2+ hours of grid charging following the discharge before abandoning the pack. You need to get the voltage well above the nominal of 144V.