Re: displayed SOC around 50%
Today i have quite long trip, not so long i was thinking before start. But i was start from 98.5%, ended at 44.5%, so consumed 54% of battery charge. efficiency was 10.5 kwh/100 km, trip was 158 km. So my calculation is (10.5*158/100)/0.54= 30 722 wh. So from this consuption SOH is 97.5% which i quite optimistic, so i will have to evaluate on the longer trip to be more precise. eGolf have 68k km.
Re: displayed SOC around 50%
You need to consume close to 90% of the battery pack to get an accurate measurement.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior, purchased in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
Re: displayed SOC around 50%
Yes, i know, but next time, when i will have longer trip.
Re: displayed SOC around 50%
Today i was measuring during driving, just because sometimes it crash i have not long as i would like. It seem that voltage level in relation to SOH is wide spread according actual current load, what i understand. So i start to think, that such drop off SOH is just some correction of SOH in interval around 50%, where maybe calibration curve have some change of the slope.
When i look at the data, from 53% down it is almost not statistically significant trend (probably there is starting typical NMC discharging plato), so hard to estimate exact SOH from voltage. i just have to measure it from 75 down to 35 to see shape of the data.
When i look at the data, from 53% down it is almost not statistically significant trend (probably there is starting typical NMC discharging plato), so hard to estimate exact SOH from voltage. i just have to measure it from 75 down to 35 to see shape of the data.
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Re: displayed SOC around 50%
I suspect you may want to measure voltage when car is not driving. When I use Car Scanner, I do not see this much noise in the data.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior, purchased in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
Re: displayed SOC around 50%
Yes, in case that i would like voltage at OCV i will measure it when car stay. But i was interested about discharging curve under load... And there is breakpoint visible to...
Re: displayed SOC around 50%
My friend just bought egolf 2019 40 kkm. We were interested about in which shape is given piece. I was testing, make diagnose over obd11.
Given egolf2019 is in good shape is my conclusion (egolf of my friend) for mechanical part, battery, etc.
I was curious, if there is phenomena around SOC 50% as at mine egolf. I just made test. I charged to 80% SOC and go to work, with little bit km more to hit discharge to SOC 53. After 3 hours i go to car and SOC was 50 % (voltage of battery at 50 SOC was +few mV higher than at 53 SOC). So behaviour the same like with my egolf (2018). I expect, that it is some typical behaviour which corespond with some change of calibration curves around 50% where NMC have breakpoint. How i wrote before, if i charge to 80% and end my trip at 62ˇ%, when i come back to car i see again 62%. Described phenomena i see at longer drive when i finish my trip below SOC 60%. Experiment with my friends egolf 2019 prove it.
Given egolf2019 is in good shape is my conclusion (egolf of my friend) for mechanical part, battery, etc.
I was curious, if there is phenomena around SOC 50% as at mine egolf. I just made test. I charged to 80% SOC and go to work, with little bit km more to hit discharge to SOC 53. After 3 hours i go to car and SOC was 50 % (voltage of battery at 50 SOC was +few mV higher than at 53 SOC). So behaviour the same like with my egolf (2018). I expect, that it is some typical behaviour which corespond with some change of calibration curves around 50% where NMC have breakpoint. How i wrote before, if i charge to 80% and end my trip at 62ˇ%, when i come back to car i see again 62%. Described phenomena i see at longer drive when i finish my trip below SOC 60%. Experiment with my friends egolf 2019 prove it.
Re: displayed SOC around 50%
I have seen this too. I don't exactly understand why this happens, but I agree it is related to the BMS calibration, and slight changes in temperature of the pack while the car is sitting. I don't worry about it - my battery pack works just fine.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior, purchased in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
Re: displayed SOC around 50%
I did some research and found that there is hysteresis in the SoC vs Voltage curve. Additionally, you need to be sure you are looking at the resting voltage of the pack, not a pack that is actively charging or discharging. Finally, it is very likely that the e-Golf SoC estimation is accomplished by Coulomb counting algorithm, and not based on pack or cell voltage.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior, purchased in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
2015 e-Golf SEL leased for three years, returned in early 2018
Re: displayed SOC around 50%
Thank you for your research. Now, we have agreed for 3 egolf, that it is normal phenomena. I have not any problem with my battery pack too, only this i was observe. I am wathing at this values when car is staying, without any charging/discharging state.