Hey everyone. I drive a convert EV made by a Turkish company on a Toyota Corolla chassis the past 10-11 months and I've done around 19k miles on it, I'm loving the EV experience and am never going back.
I also love to understand its inner workings and comprehend it fully. I need help understanding the numbers of the battery to keep track of degredation, currently, I can't.
So the battery data I have is as follows;
And the info screen of the car gives me three values;
I've researched a lot about batery SoC indication and fuel gauging. I know of two techniques; coloumb counting and voltage estimation. Since this is an EV and it has irregular loads I'm assuming this is by coloumb counting since voltage would drop significantly during a fast accelaration.
Also the SoC percentage is pretty linear and realistic, it doesn't go crazy like my iPhone does (shutting down at 20%, connecting and instantly jumping +15% etc.)
How do I calculate kWh used in a charge and keep track of real degradation? I can't find a way without finding the aforomentioned moving average X km figure.
Also this pack is not thermally managed and consumption increases a lot in winter. However car shows the average consumption to fall a lot during winter months. For example now I'm getting 4mi/kWh (250Wh/mi) and in winter it gets as low as 2.8mi/kwh(357Wh/mi) Yet this implies that cold affects the consumption of the drivetrain. However we know that battery chemistry is the one that is affected hence able to deliver less capacity. Yet SoC still indicates 100% when full. This could be a clue.
Any discussion, hint is appreciated. Thanks in advance.
I also love to understand its inner workings and comprehend it fully. I need help understanding the numbers of the battery to keep track of degredation, currently, I can't.
So the battery data I have is as follows;
- Rated Capacity: 36kWh
- Nominal Voltage: 358V
- Cell type: 3.2V, 100Ah LiFePo4 cells - 112 of them in series.
And the info screen of the car gives me three values;
- SoC in %
- Average consumption in km per kWh. (It is definitely a moving average of the past X miles but I don't know X)
- KMs of range left to drive. (directly relies on average consumption)
I've researched a lot about batery SoC indication and fuel gauging. I know of two techniques; coloumb counting and voltage estimation. Since this is an EV and it has irregular loads I'm assuming this is by coloumb counting since voltage would drop significantly during a fast accelaration.
Also the SoC percentage is pretty linear and realistic, it doesn't go crazy like my iPhone does (shutting down at 20%, connecting and instantly jumping +15% etc.)
How do I calculate kWh used in a charge and keep track of real degradation? I can't find a way without finding the aforomentioned moving average X km figure.
Also this pack is not thermally managed and consumption increases a lot in winter. However car shows the average consumption to fall a lot during winter months. For example now I'm getting 4mi/kWh (250Wh/mi) and in winter it gets as low as 2.8mi/kwh(357Wh/mi) Yet this implies that cold affects the consumption of the drivetrain. However we know that battery chemistry is the one that is affected hence able to deliver less capacity. Yet SoC still indicates 100% when full. This could be a clue.
Any discussion, hint is appreciated. Thanks in advance.