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It depends on the actual condition of the pack so there's no way to know until you do the procedure. Also the usable capacity won't reset by itself so to get the full benefit of the reconditioning you have to reset it manually. Your scanner can't do this, only an HDS or C&C can.
That 31% is concerning, the threshold for the IMA to trigger a code for a degraded pack is 20%. That said you don't know how long it's been at that value or how long it would take to drop to 20%.
 

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Oh man, this just moved up the priority list!

I got the car at auction with approx 160k hx unknown. Now it's at 177k.

When only looking at the battery meter bars in the dash without OBD2 readouts. I've noticed the bars reach max bars and down to about 3-4 pretty easily in moderate southern California highway driving. Ot averages around 2-4 bars usually. Would this type of behavior be indicative of anything? it just more evidence of 31% UC ?


Thanks!!


Car has never felt "strong" I figured it was just normal for a hybrid. But after reading and hearing more of experiences here. I think I am missing something.
 

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I just wanted to share that the Vgate iCar Pro OBD2 reader from AliExpress works great with the Car Scanner app to read the hybrid battery useable capacity. The Bluetooth 4.0 (BLE) version of the reader that I used works great with iOS devices, like an iPhone.
 

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I just wanted to share that the Vgate iCar Pro OBD2 reader from AliExpress works great with the Car Scanner app to read the hybrid battery useable capacity. The Bluetooth 4.0 (BLE) version of the reader that I used works great with iOS devices, like an iPhone.
Can you give links for the actual versions/you used/bought please.
 

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Can you give links for the actual versions/you used/bought please.
Please find the links below. If you have any questions, let me know. :)

Vgate iCar Pro (I used the Bluetooth 4.0 version): 8.24US $ 22% OFF|Vgate Icar Pro Elm327 V2.3 Obd 2 OBD2 Auto Diagnostische Scanner Wifi Bluetooth Compatibel 4.0 Auto Scan Tool ODB2 pk Elm 327 V 1 5|Code Readers & Scan Tools| - AliExpress
Car Scanner app (I used the free version on an iPhone X): Car Scanner ELM OBD2 – The best car OBD2 diagnostic solution for iOS and Android in your pocket!
 

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Can you show us screenshots of the IMA information it displayed please.
I'm interested to compare it to what an HDS shows.
Post #56 in this thread actually shows most things you can read out. Also, you can download the Car Scanner app for free, choose the profile "Honda/Acura Hybrids" when setting up, and then you can press the big demo button on the app's home screen. The app then simulates as if it's connected to the car and shows you what it can read and do. This is nice to get an impression without buying an OBD2 dongle.

EDIT: When looking at the data off all sensors and then searching for “HV” shows you all hybrid related stuff, as shown below. Please note that the values shown are within the demo mode, so not actual values of my car!

Font Screenshot Terrestrial plant Number
 

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Since my father drives a Toyota hybrid, I took some time to look into an app called Dr. Prius. This app also connects to a simple OBD2 dongle. It can determine the capacity left in the hybrid battery. It does this by making the driver do several things, like accelerating, using the AC or headlights to draw electricity from the battery, etc.

All in all, quite a process to determine the useable capacity. This got me wondering a few things:
  • Why don’t Honda hybrids need such a procedure?
  • Is the useable capacity determined by Honda hybrids (and thus read by a HDS clone or OBD2 reader) accurate or is it just an indication?
 

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I'm not familiar with that Toyota app, but it's possible that it can't access the actual data item for usable capacity so it makes a calculation based on the voltage drop from a known load. Just a guess, I could be way off.
The usable capacity seen in HDS, and other compatible units like Peter's, is a value assigned by the controller based on parameters that indicate battery health. So it represents the maximum amount of charge that the battery will be allowed to have.
 

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I'm not familiar with that Toyota app, but it's possible that it can't access the actual data item for usable capacity so it makes a calculation based on the voltage drop from a known load. Just a guess, I could be way off.
The usable capacity seen in HDS, and other compatible units like Peter's, is a value assigned by the controller based on parameters that indicate battery health. So it represents the maximum amount of charge that the battery will be allowed to have.
I didn’t think about not being able easily access the useable capacity of a Toyota hybrid. That could be the case indeed!

Thanks for the information regarding the useabke capacity of Honda hybrids. Then it’s accurate indeed.
 

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The Nimh battery Honda hybrids calculate useable capacity by counting current in/out and using voltage events/thresholds to set/reset flags.
If we use the Nimh CR-Z as our example it has seven voltage taps each monitoring twelve cells. (84 cells total)
The resting voltage of Nimh is not a good indication of the accurate SOC, so it not used like with the Lithium cars except for gross changes.

So let's imagine in a simplified example and (ignoring temperature and other effects for now) we have this pack charging descending a long hill.

The car will charge until a threshold is reached, either the pack voltage is x volts (full) or a voltage tap indicates an individual pair of sticks is full.
At that point it draws a line in the sand and says this is the start point A (Pack Full) It cuts regen and sets SOC to about 80%

Then we go straight onto a hill and climb for miles using assist all the way.
It allows normal discharge until it reaches a voltage threshold, again either a low pack voltage or an empty cell is detected.
This is the end point B. (Pack empty) It cuts assist and starts charging.

It has been counting current amps/Ah out during this time so it knows that it discharged say 4ah.
It knows the useable capacity in this window between point A full & B empty is 4Ah.

A new cell holds 6.5ah, so 4ah of that is 61%. That's our useable capacity.

Out of balance packs might have very narrow operating windows and low useable capacity.
That's why the balancing and rejuvenation is very useful. The pack is only as good as its weakest cell.

If one cell is say at 50% SOC and the other 83 are all at 75% SOC that's an immediate -25% hit on your useable capacity.
The system will recalibrate when the low cell hits empty to prevent damage even though the others all have 25% SOC left!

Nimh SOC drifts a lot over time, so each time an empty cell event occurs it resets the flags and starts charging until the full threshold is reached. (Recalibration)
This is basically it in a nutshell but a lot of stuff is going on behind the scenes including temperature and Peukert effect compensation.

Lithium is a bit different but the cells are monitored individually for voltage and the current is again counted.
Lithium can give an indication of its capacity purely from it's static voltage, so that is used in the mix.

Again if individual cells get empty/full or the pack reaches certain thresholds the useable capacity is recalculated/reset.
As there is a relationship between voltage and SOC for Lithium it also looks at what has been discharged and the expected versus the actual voltage drop.
As the cells age they will drop further in voltage for the same amount of capacity used.


The Toyota App probably watches and counts current and the voltage drops/rises to work out the expected versus actual changes.
From that it can calculate a % deterioration from the known behaviour of a new cell.
 

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Reading a few of these threads with interest. i have a (fairly old) BT OBDii code scanner that i plug in with torque pro occasionally, its always worked fine.

however, i downloaded car scanner, and i can connect to the scanner unit just fine, but not to the car??
just wondering if you had to fiddle with the settings on your app? as i say it works fine on torque but seem to hit a brick wall with CS app.

car's just hit 100,000 miles and wanted to at least check the usable capacity and if its not tip -top (butt dyno seems to indicate not as much oomph lately) do a couple charge / discharge cycles.
 

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I had no problem using Car Scanner with the same BT unit that I use with Torque. It might be worth trying a different one, just in case it's not compatible for some reason.
 
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