Found my battery's aging %, seems low -- or is it?

[phr00t]

Brought my car into the shop yesterday to check the cabin heating system. All was fine. However, a secondary goal was to get a diagnostic log printout so I could comb through it for a capacity or "state of health" percentage on the battery. Success!

On page 26 of 60, under "Battery Monitoring measured values", these two numbers pop up:

Param_SOHP 89%
Param_SOHQ 89%

"SOHP" means "State of Health Power". Not sure what "SOHQ" is, but it is the same number.

I was expecting 98-99% for a new car.. but 89%? But then it hit me... the eGolf's "usable" battery capacity is understood to be around 21-22kWh for the 24.2kWh battery. 24.2kWh * 89% = 21.5kWh. My hypothesis is, cars are sold with a SOH @ ~90%, which gets everyone their "usable" battery capacity figures. This led me to wonder... the battery warranty is 70% capacity. Does that mean I only need to lose 19% more before having a warranty claim?

I'd be very curious to see someone's numbers that have a VCDS cable, or a diagnostic report.

 

[REM]

I'm curious to learn more about this as well. The mynissanleaf forum was very informative about that battery, I had a LEAF DD that told me all sorts of information about my battery. Now I feel as if I'm flying blind in my e-Golf.

 

[phr00t]

I'm curious to learn more about this as well. The mynissanleaf forum was very informative about that battery, I had a LEAF DD that told me all sorts of information about my battery. Now I feel as if I'm flying blind in my e-Golf.

Yup, I feel the same way. I looked into buying a VCDS cable, but it is very expensive to get the right one ($249+).

The good news is, you can decode it if you can get a full, long diagnostic report printout from your dealership. I'm going to e-mail my local eGolf shop with the followup questions.

 

[REM]

I'm curious to learn more about this as well. The mynissanleaf forum was very informative about that battery, I had a LEAF DD that told me all sorts of information about my battery. Now I feel as if I'm flying blind in my e-Golf.

Yup, I feel the same way. I looked into buying a VCDS cable, but it is very expensive to get the right one ($249+).

The good news is, you can decode it if you can get a full, long diagnostic report printout from your dealership. I'm going to e-mail my local eGolf shop with the followup questions.

That's good to know. I was underwhelmed by the vehicle health report diagnostic thing in car-net, and I'm not planning on spending the $ for a VCDS cable.

 

[phr00t]

I'm curious to learn more about this as well. The mynissanleaf forum was very informative about that battery, I had a LEAF DD that told me all sorts of information about my battery. Now I feel as if I'm flying blind in my e-Golf.

Yup, I feel the same way. I looked into buying a VCDS cable, but it is very expensive to get the right one ($249+).

The good news is, you can decode it if you can get a full, long diagnostic report printout from your dealership. I'm going to e-mail my local eGolf shop with the followup questions.

That's good to know. I was underwhelmed by the vehicle health report diagnostic thing in car-net, and I'm not planning on spending the $ for a VCDS cable.

Seriously. I ran the Car-Net thing, and got a "report" which basically told me no warning indicators are being displayed on my dash. Super helpful!

Awaiting e-mail reply....

 

[phr00t]

Called my dealership & had the service lady ask the eGolf specialist.

eGolf specialist said the 89% "State of Health" value is "Good" & he didn't know about the warranty question. Getting real answers on this may be harder than anticipated.

Feel free to call your dealership's service tech & have them bounce questions off of their "eGolf specialist".

 

[vetaldj]

I have full channel maps (it shows whatever is exists and value for that) on my laptop for my eGolf that I've got from VCDS at home I will try to search for those.

Will post it here later on. That would be nice thing to monitor for sure.

I'm going to my 10K service soon so I will ask to give me that diagnostic report as well.

 

[JoulesThief]

I have full channel maps (it shows whatever is exists and value for that) on my laptop for my eGolf that I've got from VCDS at home I will try to search for those.

Will post it here later on. That would be nice thing to monitor for sure.

I'm going to my 10K service soon so I will ask to give me that diagnostic report as well.

I am wondering if you need to fully top charge the car before running the diagnostics test, or scan on VCDS, for SOC and condition of battery?

 

[phr00t]

I have full channel maps (it shows whatever is exists and value for that) on my laptop for my eGolf that I've got from VCDS at home I will try to search for those.

Will post it here later on. That would be nice thing to monitor for sure.

I'm going to my 10K service soon so I will ask to give me that diagnostic report as well.

If it helps track things down, the section actually looks like this:

Function call-up: sys x 1 0413 11 Start Stopp Kapitel 6 MQB 00011

Test step: Supply

Test step: Vehicle selection

Test step: Battery monitoring measured values

/Param_MatchRecorDataIdent 12 05
/Param_RecorDataIdent EM_prcSoh
/Param_DataRecor/Param_SOHP 89.0%

Looking forward to what you see. My car has about ~1900 miles on it, but it was manufactured in 10/14, so it is about a year old now (even though I've had it just for a month).

 

[JoulesThief]

Bump, now that these cars are getting some more miles and more checkups on them, for Battery conditions.

 

[bizzle]

Was anyone able to figure out where to look with a VCDS? I have one, but haven't bothered hooking it up since last year (and the software was still in beta in regards to eGolfs). I might hook it up today but wouldn't know where to look.

 

[phr00t]

I purchased a Bluetooth OBD2 reader & am trying to find out how to gather the battery "state of health" with it. It would be great to see how the "state of health" has decreased over my eGolf's life. There are a bunch of Android apps that read OBD2 data, but none are great for electric vehicles... except "Leaf Spy", which is specifically geared for the Nissan Leaf. Torque Pro has a "PID Scanner", which scans for OBD2 values -- one of which is probably the data I need to get the "state of health". Unfortunately, there are a ton of PIDs and I don't know how to track down the right one. I wonder if any of the numbers from my earlier post might help.... the PID is 4 digits, I think.

Anyway, wondering if anyone else found their "state of health" successfully via any means, or have tips on how I could go about finding mine with this new OBD2 scanner & an Android phone.

 

[vetaldj]

Well, back to forum after quite some time.

Sorry I was not able to check this out yet. Today/tomorrow I will connect it one more time and will see what I can find. Will post later on.

 

[schleppy]

Has anyone paid for JUST a battery check up? I have no intention of having the dealer do any work on my e-Golf unless they need to, but I want to maintain the battery warranty, and they are the only ones that can "check" the battery. Has anyone had any luck getting just a battery check up done? If so, how much?

 

[f1geek]

Good luck getting a battery capacity number from an official source. I asked at my local VW dealer and they said they weren't able to provide that information. A month later, I talked to VW rep on the phone and they informed me that VW doesn't "have the technology" to provide that information. After a lot of arguing, VW finally relented and told me a dealer could do it, but it would require leaving my car from several days to a week for the dealer to perform tests. All of these responses seem ridiculous to me as there is no way the car can provide a range estimate if the BMS doesn't know the usable capacity in real time. VW and its dealers just don't want this information made available.

I have been trying to keep track of my battery capacity over the 2.5 years I've driven the car. I have about 20,000 miles on the car now. I have found that the estimated usable capacity is highest at a high SOC and decreases as the SOC approaches 0%. Last July with an SOC of 19%, the estimated usable capacity was 19.5 kWh. Last September, at 19% SOC, the usable capacity was 19.3 kWh. This January at 19% SOC, it was 19.5 kWh. Yesterday, at an SOC of 20%, the usable capacity estimate was 18.3 kWh.

So, it looks like my car lost about 1kWh of capacity (about 5%, assuming 20.5 kWh initial usable capacity) since I began tracking the data.

 

[vetaldj]

Got some time to dig in VCDS. Well, I did not find magic number or settings yet. What I found is ability to see each cell's voltage. My car has 88 cells with 3.51-3.54 range on each. Car was not charged though. Will review this one more time. Knowing max new voltage and having this number can help us get SOH number, maybe. Need to review each cells' voltage when car is fully charged to see what it will be.

Found bunch of interesting info, history, total kWtt charged, total miles driven etc. But nothing close to state of health.

Will continue digging and will send my file for battery module to Ross Tech so maybe they can get some useful info for us soon.

 

[miimura]

Voltages don't tell you anything about SOH. They only tell you about balance and SOC. When the battery ages or degrades, it delivers a different amount of energy between V2 and V1. So, you have to find out how much energy passes into or out of the pack while it's in use. This is called Coulomb Counting. The car keeps track of this in order to have accurate SOC at any instant and SOH over time.

 

[JoulesThief]

Voltages don't tell you anything about SOH. They only tell you about balance and SOC. When the battery ages or degrades, it delivers a different amount of energy between V2 and V1. So, you have to find out how much energy passes into or out of the pack while it's in use. This is called Coulomb Counting. The car keeps track of this in order to have accurate SOC at any instant and SOH over time.

Speaking of counting Coulombs, have you done a recent battery degradation sample on your e-Golf?

 

[miimura]

Voltages don't tell you anything about SOH. They only tell you about balance and SOC. When the battery ages or degrades, it delivers a different amount of energy between V2 and V1. So, you have to find out how much energy passes into or out of the pack while it's in use. This is called Coulomb Counting. The car keeps track of this in order to have accurate SOC at any instant and SOH over time.

Speaking of counting Coulombs, have to done a recent battery degradation sample on your e-Golf?

No. Not since the last set in May.

 

[offpist]

How about these three measuring blocks?
Found them on the Gateway 19.

IDE09074-MAS08256 Vehicle properties-Max energy content 18750 Wh
ENG106155-ENG118436 EM_prcSoh-SOH_P 74 %
ENG106155-ENG118435 EM_prcSoh-SOH_Q 75 %