ReInVolt PHEV Plan

Wednesday evening, I was monitoring the battery low with the ScanGauge and started seeing some impossible values. I pulled into the grocery store parking lot seeing the traction battery level vary from almost nothing to fully charged.

When I came back out, the car would not initially start. Battery level looked bad but eventually it started up. Worse, the check engine light came on . . . not good. Regardless, I drove home without any problems other than the 'check engine light.'

About six hours later, I took the Auto Enginuity laptop out to the car and found . . . the same HV ECU-to-Battery ECU bus problem I'd seen before with the original battery. This was just the second occurrence. I cleared the code and reconfigured to monitor the traction battery for my next errand. This is not a ReInVolt problem but probably HV ECU connectors that need reseating.

One thing that surprised me was the 4 C temperature difference between sensor #1 and the pair #2 and #3. It was freezing outside and this explains why we tend to see the interior modules failing first. They do not cool as rapidly as the end modules. Ordinarily a 4 C would not matter but over a stretch of years, this would increase the probability of a problem.

Bob Wilson

 

I repeated the same approach for the ReInVolt pack (*):

	Column 1	Column 2	Column 3	Column 4
0	dV	dI	R	Pack
1	318.20 - 316.8 = 1.40 V	3.2 - 1.30 = 1.90 A	1.40 V / 1.90 A = 0.74 ohms	NHW11
2	318.75 - 318.1 = 0.65 V	3.3 - 1.35 = 1.95 A	0.65 V / 1.95 A = 0.33 ohms	ReInVolt

So 19 module pairs per pack:

• .039 ohms/module pair - NHW11
• .017 ohms/module pair - ReInVolt

* - Due to the cold, the ICE started when I shifted into "R". The voltage drop from the 21 A ICE start was 1.8 V and was used as a fixed offset. The battery continued to discharge at expected rates.

Bob Wilson