GS450h reconditioning experince

Background: Car has about 120K and sat in a yard for long periods of time in the past. I had the car for 3 years and I replaced some modules about 18 month ago. Its been good since then but not great. I notice a dip in performance back in January and got some codes P0A80 & P3012. Block #2 was at least 1V below the rest.

I decided to invest in the Prolong Charger & Discharger because I also have a newer Lexus hybrid with 240cell battery. It will defiantly come in handy in the future.

I installed the discharge ready harness & replaced Block2 & one module in block3 because it had signs of leakage. I risked it and used some old replacement modules that I got on ebay 18 month ago. The car didn't show codes but performance was a bit sluggish and the SOC still rise and fall irregularly. I drove the car for few days waiting for the weekend to use the Prolong system.

The GS450h has 240 Cell battery. Gen2 modules if I'm not mistaken.
According to Hybrid Automotive; filing phase 288-336V & balancing should be around 336-343V for this battery.


SOC was about 70% before I started.
FIRST CHARGE: only 3.5 hours and pack voltage stopped 350V
FIRST DISCHARGE: 8.5 hours from 349V to 192V
2nd CHARGE & BAL: 17 hours from 192V to 343V it stayed on 343 for at least 4 hours.

I decided to stop at one cycle to check the results but the plan is to do 3 full cycles soon.
I drove the car for 3 days now and the results are encouraging. Better performance, more stable SOC, and no error codes so far.

After 3 days and maybe 200 miles of driving I did a Hybrid Assistant HV battery test.
The test was going smoothly until about 57% SOC; Block# 1&14 Voltage dropped and SOC dropped really low but no codes. I attached the test results.



I'm going to replace these blocks eventually and I'm also planning on replacing the bus bars with nickel plated bars in the upcoming months.

I wonder if 3 cycle prolong reconditioning can help revive them or is it pointless at this point? Would the lower discharge cycles expose the weaker cells and cause them to fail? Can someone with experience in grid chargers look at the numbers and tell me if it's worth it to waste few days charging or discharging?

Thanks in advance.

 

I started 3 cycles yesterday

CHARGE 59%SOC: 4.5 hours voltage stopped at 347V
1ST DISCHARGE: 7.5 hours down to 192V

Now its been charging for over 12 hours and voltage is 325 and rising.
I'm gonna discharge it to 144V then 120V. That's as low as 0.5V per cell.

While the car is charging I was going over trip reports from Hybrid Reporter I noticed some odd numbers. The report shows some blocks at ZERO voltage for a split second. Basically it was an acceleration attempt while the gas engine is off and the car is idling. it didn't trigger codes and I don't remember noticing a power dip while accelerating. I'm gonna continue the 3 cycle conditioning and do some tests after but I can't make sense of these values.