bobkart
Well-known member
When I use a public charger and get a report of kWh delivered, I often feel like the amount of SOC increase doesn't jive with the energy delivered. It charges "too easily": for the amount of energy delivered, I shouldn't see so much SOC increase. I also see this with home L1/L2 charging.
The most recent example of this is a 14.38 kWh L3 charge, where SOC increased from 22% to 100% (a 78% increase). Next to this entry in my log, I noted: "How does 14.4 kWh fill nearly 80% of a 24 kWh battery?".
Setting aside onboard charger inefficiencies, 14.38kWh / 78% yields a battery capacity of 18.44 kWh. I know there is reserved capacity that brings the 24 number down to closer to 21. With onboard charger inefficiencies that 18.44 number drops to 16.6 (using 90% efficiency).
Today I saw this in a nearby thread:
Running the numbers from the above charging situation gives 0.184 kWh/%, yielding only 74% capacity compared to brand new. Yet I still have 12 bars and LeafSpy is giving me SOH number around 90% (the full range I've seen over the last 100+ days of using LeafSpy is 87%-94%). I checked some L3 session results from earlier in the year and the 0.18 number holds pretty well for those. These are 5-6-temperature-bar charges so can't blame too cold or hot.
Any idea what's going on? Are charge sessions being underreported? Seems unlikely. Is that 0.25 kWh/% number too high? Not seeing where else the discrepancy could be coming from (aside from actual capacity loss).
The most recent example of this is a 14.38 kWh L3 charge, where SOC increased from 22% to 100% (a 78% increase). Next to this entry in my log, I noted: "How does 14.4 kWh fill nearly 80% of a 24 kWh battery?".
Setting aside onboard charger inefficiencies, 14.38kWh / 78% yields a battery capacity of 18.44 kWh. I know there is reserved capacity that brings the 24 number down to closer to 21. With onboard charger inefficiencies that 18.44 number drops to 16.6 (using 90% efficiency).
Today I saw this in a nearby thread:
SageBrush said:A brand new 24 kWh battery pulls about 0.25 kWh from the meter for every 1% increase in battery SoC. The 0.25 kWh/% takes into account charging losses.
Running the numbers from the above charging situation gives 0.184 kWh/%, yielding only 74% capacity compared to brand new. Yet I still have 12 bars and LeafSpy is giving me SOH number around 90% (the full range I've seen over the last 100+ days of using LeafSpy is 87%-94%). I checked some L3 session results from earlier in the year and the 0.18 number holds pretty well for those. These are 5-6-temperature-bar charges so can't blame too cold or hot.
Any idea what's going on? Are charge sessions being underreported? Seems unlikely. Is that 0.25 kWh/% number too high? Not seeing where else the discrepancy could be coming from (aside from actual capacity loss).