Saga of Prius Prime Flat

Thanks for the link. I read AHetaFan measured that on a lithium battery. I can't imagine that kind of current into the stock AGM.

moto g(7) power ?

 

Wasn't that a larger automotive lithium battery, not the factory lead-acid unit?

 

Good catch. And I haven't clamp-metered the charging current on my Gen 3 with the factory battery.

I have done so on a Gen 2 with the factory battery and its lower 13.8 charging voltage, and not seen it dump more than 8 amps even into a very low battery.

It's still the case that Gen 3's charging voltage is more like 14.7, and that extra volt can make a substantial difference in the current supplied to a 12 volt battery.

 

With that Gen2 charge rate, a 10 mile drive taking about 15 minutes, would put only 2 Ah into the battery, tiny compared to a full charge that the OP thought he was getting. If the Gen3's higher voltage produces double to triple the charge rate, that is a great help, but still leaves the battery fairly low after just 15 minutes, far from full.

And somewhere in the charge cycle, when the battery is up to some level (I don't know just how much), the Gen3's charging voltage does step down, so a true full charge would still takes a long time. Probably longer than anyone's daily commute, if the goal is to get a full charge in just one commute cycle.

 

Anyone ever gone out in the morning, popped the hood from the passenger side and checked the charge on the 12V and found it to be at 100%? I've tried a few times. Never anywhere near 100% and I wouldn't expect that. I checked mine yesterday after it sat for a few days and it was 50% according to the display on my charger. Started right up!

 

Instructions say to measure voltage from the battery terminals only. The under hood jump points are not an option. I assume there’s a logical reason why, but I wouldn’t use that under hood value.

 

i have done tha, but don't have any equipment to measure percent, just voltage

idk if it's linear though. wouldn't 50% be 6.5 volts?

 

Prime (and gen 4) has battery under the hood. No jump point.

Posted via the PriusChat mobile app.

 

Thank you! I didn't remember that!!!

moto g(7) power ?

 

It isn't linear. 50% is something like 12.2V for a flooded battery like in most cars and it's about 12.3V in an AGM. 11.8 volts is 0% for either. 100% is 12.7-12.8. That's according to this chart. Battery voltage and state of charge - Energy Matters

It's good to remember, though, that those charts are just guestmations. I see a lot of them posted here and they are useful, but only as a rule of thumb, not as a precise measurement. Actual SOC percentage is much more complex involving specific gravity, open circuit or with a load (and how much load), temperature, number of cells, and so on. For example, what my battery charger interpreted as 50% was 12.34 volts. Closer to 70% according to the chart I qouted. Still not even close to 100% but obviously more than enough to do its job.

Edit to add:
This article is pretty informative and easy to read.
Battery State-Of-Charge Chart | 12 Volt Battery Voltage & Specific Gravity

 

My TPMS would activate AFTER the tire was flat. Have had 4 flats with my Advanced!! No warning beep; far too late with very tiny visual warning. This is a critical problem (NO SPARE TIRE!) that demands correction.

Posted via the PriusChat mobile app.
AChoiredTaste.com

 

Mine informed me of having a squishy tire.

This ended up a slow, but obvious leak...

 

Fortunately, getting a flat fixed isn't a big deal. I was able to redeem road-hazard coverage... even during stay-at-home. Got a replacement, rather than a patch.

 

The only correction you can do is to not buy a car sans spare*. This keeps you in the pink, and might wake up the manufacturers, if it catches on.

* Not exactly true, but I draw the line at dropping $30K for a new car, and THEN having to cobble together all the missing stuff.

I'm sure To

 

Do you mean "no warning" or "constant warning?"

It seems to me that the only "downside" was that your 12V battery went flat. The tire seemed to come out okay.

 

I recall Honda did just that with an automatic Fit. The stick shift version did have the spare, and for a bit over $200 you could add it to the automatic. I thought that was usury lol. At least the swap was very simple:

Toyota seems to burning their bridges on the spare though: even where it is possible, it involves well over a grand to swap all the pieces involved. And the plugins: no chance.

 

@JTEM your experience has me thinking: if you have a flat, and use sealant, and it's effective, it can subsequently very difficult for the tire place to find the leak. They're relying on telltale soap bubbles from the leak, and there won't be any. For a while...

Pretty much toasts the tire?