Time to Diagnose the Battery

For Hybrid Assistant app, you can use any cheap Android phone that is running Android OS 4 or higher. Any working Android phone you can find now would be running version of Android OS higher than 8. You can use Carista dongle, but it may be slow. The app developer recommends using OBDLINK LX.

But I really don't know what you are trying to record using it. For one thing, even if your traction battery is really degraded, it is not warranted by Toyota. Even the initial 25 miles is not a promised mile. The term "Your mileage may vary" apply here.

 

Short version: Film a drive when you first get your car, under carefully observed conditions. Each year under those same conditions (route, speed, traffic, temperature, wind, etc), repeat the drive.

I did that and noticed no difference at all after 2 years, see below. I achieved a little over 30 miles each time. Keep in mind, there is no promise of any particular range. It is only an estimate. Exactly like MPG, it is just a standardized measure for the sake of purchase comparison. When you read the fine print, you'll find variation is a normal outcome.

June 2017...

June 2019...

 

No battery-cell condition AFAIK. I thought Dr. Prius has that diagnosis, but I have never used it myself, and I have read elsewhere that the app is not highly accurate. You might be able to diagnose the cell state using Techstream better, but again I don't have an experience with it. For charging margin SW, there is no known apps that can change the margin. In fact I have never heard or read anywhere that this margin changes ever. For me it has always ranged from ~83% to ~12% on HA corresponding to 100% to 0% SoC on the dash.

 

Aftermarket apps, like "Hybrid Assistant" and "Dr. Prius" are routinely discussed on this forum. That's your answer.

 

In my personal and anecdotal observations, LiOn's being used today have A) the largest degradation over the first couple of years and then the rate tapers and B) warmer climates have larger rates of degradation.

GOOD LUCK!

 

I'd just add that there are a lot of things that change gas mileage on our favorite car. Tire pressure makes more of a difference than I would have guessed. Windows down, AC/heater, road conditions, oil type, speed, they all make a difference. I have over 40,000 miles on my prime and the average miles shown by the display is about 3 mpg lower than about a year after I got the car, but I know my tires are slightly lower than normal right now. (27 miles of charge at start of commute) Also remember that that display is just a guestimate, that's how far it thinks you can drive and it really really isn't a very good guess.

 

I have no clue why that would happen. It's quite bizarre.

 

HA shows the actual SoC of the traction battery, but estimating actual capacity in kWh value stored in the 100% SoC battery turned out to be somewhat convoluted. My feeling is that the actual capacity in kWh is so variable depending on the various extrinsic and intrinsic conditions, that no easy way to estimate this number from know other data.

I have no idea why your kWh used from the wall is varying as much as you state. In my 2017 PRIME, over three years a full charge from the wall was consistently above 6 kWh. See the graph below. GoM, on the other hand, showed vastly different numbers on a full charge from low of 21miles to high of 45miles. Using GoM as a measurement of traction battery capacity variation is a bad idea, IMOH.

 

have you ever tried driving it until the juice runs out to see how many actual miles you get?

 

Well if you want to stick with your iOS device you can use the same app I use called OBD Fusion. Had to pay $20 for it but it does record things like individual cells voltages, internal resistance, very specific temperature logs, etc. I used the same Bluetooth OBD dongle I used with the PiP. It can get really deep very fast and even has diagnostic modes for those who know what they are doing. It saves to log files in CSV format and I've attached an example in Excel format. Yes you can get individual cell voltages and other items but I would get the overall battery voltage first before diving into the details.

 

is that tootin' around town or something more demanding?

 

That looks like a great app! May I ask a couple questions?
1. Pricing. It says $9.99, but then they charge $5 for oxygen sensor results. That's pretty clear. But what do you actually get with the "On-board monitoring Tests" for $6 and the "In-performance Tracking Counters" for $9? The description isn't clear what those are. DO you know?
2. I assume that it already has Prius Prime PIDs. Do I assume correctly or did you have to install them separately?

Thanks. I'll probably get this either way, but it would be nice to know which extra cost modules I'll want.

 

I never installed the O2, performance or monitoring tests. But I believe they will charge you another $5 for the Prime PIDs and another $5 for the Lexus PIDs which I used for my wife’s NXh. Overall I’m pretty pleased with the just the basics.


iPad ? Pro

 

Got it. Played with it. LIKE IT! Thanks for the tip. When I got the PIDs, though, the Lexus & Prime ones were combined for $9.99. Nice little self selected and purchased present to start by birthday. LOL!

 

yeah, you should be getting at least 25 doing that