How to test HV battery state of health on your Gen 2 (answer)

Here is a test today, was only 70 degrees. Will redo later this week with it warmer. Fan blower was kicking on and off is the current fluctuation you see on the chart. Had a little hiccup with the discharging this morning and wondering how this chart looks so far.

 

Sorry about that, here is the csv. Had to washed the car to see how much hail damage we got

 

Side note had my son help me out...this come into play later.

I followed your tips except for discharge I did the
2 x 200W bulbs to 200V
2 x 72W to 140V
2 x 25W to about 130V
Second discharge I did the
2 x 200W to 183V
(ask son to check it throughout the night and change to the 25w bulbs when it hit the 185 mark. I wake up in the morning, about 4 hours later to check what voltage was at and bulbs was not lit and voltage was 12V. He put the 72W bulbs in instead of the 25W. I was little peeved to say the least)
Finished up the rest the test as you outlined.

I was thinking about popping off the cover to see the date codes of the battery just to make sure. Figure I will do that another day.

Climate in St Louis area is all over the place last few months but otherwise is pretty mild. Driving condition is 60-70% highway and the rest is city.

Update: first initial estimate for hail damage is $1500-2000. Have an another appointment at another shop with insurance claims adjuster meeting us there on Monday for a better estimate. Figures since the body was so nice

 

Wow that is a pretty massive improvement for such a high mileage battery! I'm planning on performing the health test this afternoon on my 2007 with 125k. I've been keeping an eye on those grid chargers and trying to decide if they are worth the price to keep my HV battery in good condition for longer. This might just push me into the buyers circle depending on how my battery fairs this afternoon.

 

I was surprise at the improvement I got right off the bat. I can actually keep the car in electric mode more while driving. Figure we will see how many mpg we hit with next fill up.

 

Well I did the test this afternoon, but I don't currently have a techstream adapter or the software. I do have a bluetooth OBDII reader and Torque Pro if that can be used similarly. Started with unplugging the white connector and waiting the 60 seconds to get everything back to baseline. Put in drive and charged up until it would blink back and forth to and from the battery with full green bars. Turned on headlights, defrosters, AC down to low with fan on max. Battery held out to 5:34 and the last 3 bars dropped very quickly like going from blue to ICE running in a matter of 30 seconds. If the 9.5% rule of thumb checks out that puts me at about 52.82% capacity on my 2007 Prius with 125k miles. Definitely have been seeing degrading mileage recently, been in the mid to upper 40s when I typically average low 50s. I will give the test one more shot this evening when temps and my motors

Update: Tested again this evening and same results about 4:54 seconds. This time I loaded up the extended PIDs for Torque and the drawn amps was 16.4 amps on average with a delta V of .1 throughout the drain. I will see if I can get a graph/chart plotted on Torque with the same graph fields shown in previous posts.

 

Steve, could you take a look at my discharge test file. It's a bit of a mess as it includes the forced charge, the discharge, and the idle charge. I can clean it up first if you would like. I hope I am calculating the capacity wrong, because the way I calculated it, my battery is only at about 31%.

The ir on all the modules is 0.026 - 0.027. The outside temperature was 72 degrees.

This is my pre-grid charge test before charging with 3 APC-35-350 wired in series. I plan to follow your charging/discharging instructions and will post my results afterward.

Thanks Dan

Edit: spelling and phrasing

 

Thanks Steve
I was a afraid it would be that bad. I will do the charge/discharge and post the results when I can.

 

Hi

I ran your test, and the ICE kicked in at just over 6 minutes (6:05), so I thank that translates to 57.79%. I have a 2008 with 125K miles, so I guess that isn't too bad. I am in So Cal, and I ran the test in 73 degree weather.

About 6 weeks ago, my mileage dropped from about 45 MPG to about 30 MPG. The only thing that changed at that time were:
1. Oil Change
2. New Air Filter
3. New tires (Yoko Avid Touring S)

Note that at the end of April I drove from Los Angeles to Phoenix to Flagstaff to the Grand Canyon and home. Averaged between 30-32 MPG.

On the up way to Flagstaff, the ICE felt like is was going to die. Almost like I was running out of gas. The same thing happened during this test while force charging the battery. From about 77% to 82% (which is about when I stopped), the ICE sounded like it was going to die. Started sputtering a little, and sounded like it had lost all power, very similar to what I experienced in AZ. I wonder if this has something to do with my issue.

Anyway, I have attached my output from Torque. I'm not sure if I captured all of the appropriate measures, but I know I got some.

Can you take a look and let me know what you think?

Allen

 

kieth
is it advisable to run a test on a battery already giving a bad battery code. ( I can't remember the code but it's the major one). I read that this could damage other components. I would like to know if any modules are usable.

 

For Steve. I went ahead and took off the cover of the battery to show the cells for you, also the serial number on the metal case. Will do a re-test next week when the month ends.