Battery life expectancy - validation needed for Dr. Prius App

My car is not plug in . It is normal prius hybrid 3rd gen . i bought your app and installed it but when i need to check the life expectancy test it failed in second stage because the engine starts to run . so please help me how to finish the test ?

 

Hi jack,

Just used your app today for the first time using the Casrista OBD interface. This is a 2012 Prius with 521 K KM or 323 Miles on the ordinal traction battery. I ran the life expectancy testy twice.
The first test I lost connection with 39 seconds left in test.
The next test when to completion but the engine started in the middle of the test. The results stated 92% life left so I do not know how much this modified the results. Outside temperature today was 32 F. I live in Ontario Canada.
Is there any way to stop the engine from starting ? I do not think so because it is computer controlled.
Voltage was balanced to within .05Volts and 3 blocks were 25m ohms all other were 24.
I think the battery is in pretty good shape for its age and mileage.
What are your thoughts.
I just love your app.

Charlie

 

Turn off the climate control while doing the test.

 

Thanks for the input.
As you know you need to keep the current drain in the 6.5 amp range while doing this 15 min test, so i need nearly everything running in the car to get this drain. Rear and front defrosters , AC e.g. to keep in range. Will do the test again.
The result was 92% of life left in battery but i do not believe this because the engine did start.
Thanks for the input.
Charlie

 

Well, more specifically I mean turn off the heat, as that comes from the engine. Running the AC with the temperature set to "LO" should be OK.

 

Why should it be free or cheap? This tool is important and valuable

 

I’ve done the life expectancy test a couple different times. First result was 46% life left and the second done a couple weeks after the first was 52.95%. I’m also curious if an educated guess can be drawn from the percentage in terms of life left. I’d venture to say I might have a year and a half maybe? I put on about 20K miles a year. 2010 132K.

 

You might be better off contacting the app developers directly as this thread is quite old and they might not be checking it. There's an email address in the original post.

 

I don't mean to disparage this app, a LOT of Prius owners use it and recommend it.

But I don't quite understand how a life expectancy estimate for a battery can really be made.
Isn't any evaluation or feedback about the batteries condition only based on how the battery is performing at that very moment? On that particular day?
And isn't Hybrid Battery usage by definition a lot of unpredictable, HSD, environment and Driver controlled variables?
In other words, one persons 50% life..would be anothers 75% life or vice versa? Chronological life expectancy remaining is nearly impossible to predict.
So if you've driven for 8 years on an original battery...a 50% life remaining reading DOESN'T mean you have another 8 years. It only means that by whatever parameters the software uses to evaluate the condition of the battery it's applying a 50% life remaining definition.
But isn't that definition non-static?
Depending on the chemistry of the battery, vehicle usage itself, couldn't you take the same test in a few month and get a totally different reading?
It seems to me, evaluations of a batteries condition can only be reflective of the battery as it is being read at that moment, and not really be extrapolated to any possible life remaining future.
That doesn't mean the test isn't valuable. It could help a potential used Prius buyer determine whether the Hybrid Battery in an unknown used Prius is abnormally weakened, or it can give current owners SOME idea that their battery isn't sprinting towards deaths door.

Long term however, I'd be dubious of "Life Remaining" diagnosis.

 

So far I've only done the static test. Maybe there's value enough in that? It seems somewhat comparable to doing a simple voltage check on a 12 volt battery, vs a "load test".

It would be really great if the developer could come up with "load tests" that are quicker and don't require so much involvement. Something that could put the battery through it's paces without so much effort.

Also, the accel/decel test, that's relatively easy, not much mention of it. How does it compare to the life expectancy test. Still, I haven't managed to do the accel/decel test either, lol.