[Poll + Tracking] HV battery state of health tracking (SOH) w/ self updating analytics -- crowdsourced data (add yours)

[flapjake314]

Hi everyone, I used google forms to help all of us >>track our high voltage battery state of health<<

• you can input data as many times as you want, that way you can even track yourself over time with this (just be sure to type your user name, which is otherwise optional)
  • this is for state of health, not state of charge -- you need an OBD reader to pull SOH, i bought this one from temu for $4 and it works fine, there's a million other choices
• all data is publicly viewable and self-updating with new survey inputs
• if folks think questions in the survey need to be changed, want to see different analytics, or want to get involved in this tracking feel free to reach out to me via DM
• extra shoutout to @AngryMan who started tracking this manually in this thread. he collated all of the inputs from the thread as of Aug 13, 2024 and i already input that into this tracker

Analytics and outputs are viewable right here, you can feel free to download and/or further analyze the data at any time because it self-updates based on the survey

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[flapjake314]

[Reserving the first post, I will post a static copy of the latest data so people who just want to glance don't have to leave the forum]

Link to a user who ran a multi-variable analysis across the factors.

As of 1/27/25, Age of battery vs SOH

As of 1/27/25, Miles drives vs SOH

As of 1/27/25, Battery cycles vs SOH

 

[phidauex]

Thanks for getting this started - I threw in a few snapshots from different measurements I've taken over the last few years.

Can you add an SOH vs. Battery Age (days) graph as well? There is evidence that on EVs, calendar aging is the biggest driver. You may also want to represent the graphs showing the independent variable on the X axis (time, miles, etc.), and the dependent variable (SOH) on the Y axis, it may make things a bit more intuitive to review.

 

[bshaw]

Can you add an SOH vs. Battery Age (days) graph as well? There is evidence that on EVs, calendar aging is the biggest driver.

Instead of collecting model year on the survey, you could change that question to "Build month", as indicated on the door jamb. Mine was built 12/20, and would be almost a year older than 2021 models build in say October of 2021.
Like @phidauex said, age is more important than mileage in determing SOH.

Also, thank you for collecting this data and presenting the charts. It will really help answer those wondering if their battery health is an outlier or roughly in range with everyone else.

 

[flapjake314]

Thanks for getting this started - I threw in a few snapshots from different measurements I've taken over the last few years.

Can you add an SOH vs. Battery Age (days) graph as well? There is evidence that on EVs, calendar aging is the biggest driver. You may also want to represent the graphs showing the independent variable on the X axis (time, miles, etc.), and the dependent variable (SOH) on the Y axis, it may make things a bit more intuitive to review.

i flipped the axis as you suggested, clearly i didn't do well in statistics class

i originally had a question re: battery age but ended up deleting feeling the model year + miles would give you enough resolution on the same topic.

the problem with adding the age is it potentially adds a lot of bad data that is hard to validate -- people who put their purchase date for example, or the battery date vs the build date. it's harder to know the manufacture date by heart, OBD (mine at least) doesn't show the date but rather age, and i was worried it would discourage completion of the surveys. finally, google survey didn't have a way just to enter month + year, only month + day + year...

open to suggestions and thoughts, wanted to keep it simple and usable balanced with still yielding good results, so feel free to propose good ways to ask the question or easy-to-follow instructions to find the info etc

 

[flapjake314]

if anyone has ability in statistics, i'd like to understand how the 4 variables are correlated (and how strong the correlations are) within the dataset: SOH, mileage, age (currently proxied by model year), and DCFC frequency.

i of course know how to do it with 2, i think know how to show it with 3 (that's my bubble graph), i have no idea what to do with 4. and based on that maybe we then think about which questions we add / remove etc

the other thing i haven't figured out how to make useful is some kind of standard deviation metric, to another poster's point about knowing where on the range you sit. i have the trend line and of course can calc the standard deviation but i don't know how to make it easily useful for any forum member

 

[Mach-Lee]

Thanks for fixing the graph axes, that was driving me nuts before.

From the studies I've read, the calendar age of the battery is the greatest determinant of EV battery degradation, followed by mileage (most people don't drive enough miles to beat calendar aging, only if you drive like >40k per year). However getting precise battery age from everyone may be difficult. The battery age is a parameter that's accessible with the scan tool, but the build date of the vehicle should be close if people know that. The sticker on the B-pillar can get you the build month without any fancy tools, that might be the best you can do in most cases.

 

[flapjake314]

Thanks for fixing the graph axes, that was driving me nuts before.

From the studies I've read, the calendar age of the battery is the greatest determinant of EV battery degradation, followed by mileage (most people don't drive enough miles to beat calendar aging, only if you drive like >40k per year). However getting precise battery age from everyone may be difficult. The battery age is a parameter that's accessible with the scan tool, but the build date of the vehicle should be close if people know that. The sticker on the B-pillar can get you the build month without any fancy tools, that might be the best you can do in most cases.

ok i will add a question to include build date as shown on the door sticker. there will be no data on this for a while since the original data collected by angryman did not include this so we'll need to let the datapoints gather

i would ask the group if we should consider deleting various aspects of the existing questions to try and keep the request list short. like do we need the model year (since we have build date now) or the model (select, premium)

 

[steveg95]

Hi everyone, I used google forms to help all of us >>track our high voltage battery state of health<<

• you can input data as many times as you want, that way you can even track yourself over time with this (just be sure to type your user name, which is otherwise optional)
• all data is publicly viewable and self-updating with new survey inputs
• if folks think questions in the survey need to be changed, want to see different analytics (i'm much better at excel than google sheets), or want to get involved in this tracking feel free to reach out to me via DM
• extra shoutout to @AngryMan who started tracking this manually in this thread. he collated all of the inputs from the thread as of Aug 13, 2024 and i already input that into this tracker

Analytics and outputs are viewable right here, you can feel free to download and/or further analyze the data at any time because it self-updates based on the survey

Where can you find this information about the HVB? So you have to have a scanner to read it?

 

[flapjake314]

Where can you find this information about the HVB? So you have to have a scanner to read it?

i just edited the OP to instruct everyone that they needed an OBD reader to pull SOH. i used this one from temu for $3, works fine for me...

on a separate note someone entered a datapoint that was 61% SOH with 500 miles on the odometer, i have DM'ed the person to clarify but have quarantined the data in the meanwhile. if true they should just get their car warrantied... not sure it's useful to create a dataset incorporating broken cars, although seeing how many outliers there are i guess is still useful

 

[Benewil]

Please delete my response. I quickly read this and didn't realize that I don't know my HVB SOH, as I am not with the car and stupidly put down the present SOC.

 

[Jerrytball]

Hi everyone, I used google forms to help all of us >>track our high voltage battery state of health<<

• you can input data as many times as you want, that way you can even track yourself over time with this (just be sure to type your user name, which is otherwise optional)
  • this is for state of health, not state of charge -- you need an OBD reader to pull SOH, i bought this one from temu for $3 and it works fine, there's a million other choices
• all data is publicly viewable and self-updating with new survey inputs
• if folks think questions in the survey need to be changed, want to see different analytics (i'm much better at excel than google sheets), or want to get involved in this tracking feel free to reach out to me via DM
• extra shoutout to @AngryMan who started tracking this manually in this thread. he collated all of the inputs from the thread as of Aug 13, 2024 and i already input that into this tracker

Analytics and outputs are viewable right here, you can feel free to download and/or further analyze the data at any time because it self-updates based on the survey
[/QUOTE

Hi everyone, I used google forms to help all of us >>track our high voltage battery state of health<<

• you can input data as many times as you want, that way you can even track yourself over time with this (just be sure to type your user name, which is otherwise optional)
  • this is for state of health, not state of charge -- you need an OBD reader to pull SOH, i bought this one from temu for $3 and it works fine, there's a million other choices
• all data is publicly viewable and self-updating with new survey inputs
• if folks think questions in the survey need to be changed, want to see different analytics (i'm much better at excel than google sheets), or want to get involved in this tracking feel free to reach out to me via DM
• extra shoutout to @AngryMan who started tracking this manually in this thread. he collated all of the inputs from the thread as of Aug 13, 2024 and i already input that into this tracker

Analytics and outputs are viewable right here, you can feel free to download and/or further analyze the data at any time because it self-updates based on the survey

I did the basics from your original post put my state of health the build the car, my username whatever else we need to add in the future I guess you’ll have something to click on and drop down and pick thank you.

 

[67 Stang Convertible]

Question (and forgive my ignorance): Are all OBD readers essentially the same? Does it not matter if you have an EV or ICE? It is essentially just a tool to "read your computer/car"?

 

[flapjake314]

Question (and forgive my ignorance): Are all OBD readers essentially the same? Does it not matter if you have an EV or ICE? It is essentially just a tool to "read your computer/car"?

i'm told there are some compatibility differences and to look for ELM XXX i forget the number

that said all the ones on temu were ELM XXX and i picked a random $3 and it worked so... either i'm lucky or they mostly work

i'm guessing the very old ICE ones won't

 

[Jerrytball]

Hi everyone, I used google forms to help all of us >>track our high voltage battery state of health<<

• you can input data as many times as you want, that way you can even track yourself over time with this (just be sure to type your user name, which is otherwise optional)
  • this is for state of health, not state of charge -- you need an OBD reader to pull SOH, i bought this one from temu for $3 and it works fine, there's a million other choices
• all data is publicly viewable and self-updating with new survey inputs
• if folks think questions in the survey need to be changed, want to see different analytics, or want to get involved in this tracking feel free to reach out to me via DM
• extra shoutout to @AngryMan who started tracking this manually in this thread. he collated all of the inputs from the thread as of Aug 13, 2024 and i already input that into this tracker

Analytics and outputs are viewable right here, you can feel free to download and/or further analyze the data at any time because it self-updates based on the survey

So I’m sure this is a stupid question, but after I input everything on that Google form, where can you see that information with your name your car and everybody else’s vehicle, that’s an option? Or you’re not gonna be able to see other users data.

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