Weird HSD behaviour

Yes I think you're going to be opening that HV battery it needs attention .

 

I watched the Dr Prius video, and everything looks normal to me. There is no need to be concerned about hybrid battery. Everything is working like it should. Just drive the car. If there is a problem with the hybrid battery, you will get warning lights on the dashboard.

 

Considering your battery is sitting at >65% state of charge and you're still charging it at 50-70 amps, I would say.....stop charging it, it doesn't want to be at that high of an SOC. Normally it stays between 62ish% and 42ish%

 

I’m not sure what you’re getting at here. The OP is driving the car and has no control over how the battery ECU determines when and how much current to send to the battery. If you’re assuming the OP was force‑charging it, again, the battery ECU will only permit what it deems safe. You cannot charge the battery to more than 80% SoC this way.

From my viewing of your two videos, I did not see this behaviour. It looked very normal to me given the speeds you were driving. I would have liked to see a stretch at a steady speed (say 45 kph and 70 kph) on cruise control, just to see what it would do there. Your videos showed a lot of acceleration and deceleration while driving, but the short stretch at 82 kph at the very end of the second video looked good.

Your Dr Prius screenshot showed some values higher than I would like to see when the battery was charging, but otherwise it all looked normal. I have no idea whether that voltage is within the acceptable range, as I have never made such observations on my own car. Most importantly, the voltage difference never exceeded 0.12 V between the highest and lowest blocks.

 

I think it looks pretty normal. What is the real operational problem?

1. Much lower mpg on a tank by tank basis?

2. Hybrid battery codes from Dr Prius?

3. The state of charge bar graph going low and taking too long to recover?

4. Any dash lights suggesting problems?

5. Have you been force charging based on Dr Prius hv battery testing instructions?

6. Any other observed driving behavior changes (not based on the energy monitor screen)?

If there are no codes, no dash lights and no driving problems the dealer won't be able to tell you much other than its ok and come back when hv battery codes or driving issues show up.

 

Ok, let me clarify.
If you're force charging it, especially at those rates, you're 100% covering up/hiding true module voltages that could be evaluated for determining the condition of the battery. If you want to use voltages to see if there's anything obvious going on with the HV battery, you don't do it when charging at 70 amps and high SOC unless you're purposely trying to turn a high IR module into a grenade, but none of his even show a mid-value. Maybe I'm wrong, but that's just my experience from working on a couple hundred Gen 2s. Personally, I see nothing on those screen shots that would lead me to think there's a HV battery problem, but that charge rate hides the normal delta V between those modules.

 

Looking at your amps being charged into the battery when it is already above it's 'normal' control band. The only way that should ever happen is if you're slamming on the brakes, which would make it very hard to take a photo, so it leads one to believe you are performing what some people call force charging. This would be using the accelerator pedal to 'rev' the engine to make it charge the HV battery (while car is stationary).

Under what conditions were those photos taken? Was the car being driven? Was it sitting still? foot on the gas? off the gas? in Drive? in Park?
Because...if your battery is being placed under that high of a charge level and all you're doing is sitting there or driving steady state, you DO have something wrong and you're going to smoke that battery.

 

Dr Prius force charging (not recommended by Toyota) is to engage emergency brake, foot on brake, car in D and press the gas pedal.



The question was to determine if you were doing it for some unknown reason.

Dr Prius wants a force charge as a starting point for their "Life Expectancy" test, which then drains the battery quickly to guess remaining capacity based on timing. Again, not sanctioned or used by Toyota.

Dr Prius is supplied by a company wanting to sell you aftermarket hybrid batteries.

The ONLY way I have seen the hybrid system overcharge the hv battery starts with a full battery, typically from a long downhill, followed by an overnight off period when the ambient changes dramatically. At that point the hybrid system will stay in ev for an extra mile at 40 mph or less until the excess battery charge (higher than normal capacity) is quickly used up.

I have seen this twice in 22 years of Prius ownership over 500,000 miles.