A few questions:
- Is there anything in your manual that suggests charging to 100% for battery health? Typically for your battery chemistry, NMC I believe, that doesn’t do what some LFP batteries do which is balance the cells for your BMS and a 100% charge can be recommended weekly. But you don’t have a LFP battery. Can you screenshot anything from Lucid that says charge your NMC battery to 100%?
- How can you use battery SoC to “reverse engineer” a battery SoH percentage? Aren’t your range readings based on algorithms that are guessing range based on driving habits, tire wear, load etc.? I don’t think there’s a formula for SoH. It just is what it says, if you can find it.
- Does anyone have a screenshot of their current SoH? If so how did you get there?
- I highly doubt anyone has a battery health of 100% unless the car is brand new. Also, NMC batteries are built for performance and range so they lose more battery health early before settling in and then with good management you should be good until 84% but that’s not a number you can get unless you’re a Lucid tech. Isn’t that correct?
- Is there a Lucid tech on here that can confirm or deny the Lucid screenshot that says “Display the current SoC as a percentage of battery health” is not the real number but that techs can see the real number?
- What OEM tools do you use to get S0H, pack and cell health? Are their physical port readers or is it all OEM through the cloud?
Lucid does not directly give us SoH in the car, but it’s in the telemetry. See the
second post on this thread for the community developed API, which can be used to reverse engineer and/or validate the SoH.
For the Gravity, the SoH field is 0, but we can calculate it from the other stats (see
stats that I pulled). It gives current SOC (both % charge and kWh), so we can calculate the total usable capacity at 100% charge. We can compare this to the original usable capacity (also given) to calculate SoH.
Although we can’t see battery energy in kWh from the in-car displays, we can substitute rated range (not dynamic range) for energy when calculating battery SoH. As an example for my GDE, when new, 117.39 kWh = 420 miles from the telemetry. When battery health goes down, 100% charge will show less than 420 miles of rated range. Yes, we are assuming miles/kWh remains constant, but it would be silly if that changes over time instead of the amount of energy the battery pack can hold.
How can the battery health stay at 100% after owning the EV for a while? The health (and range) is based on the
usable capacity instead of battery pack size. There is a buffer between usable and pack size, and the initial battery degradation eats into this buffer. In the Gravity’s case usable is 117.39 kWh vs. a pack size of 123 kWh. At some point, the degradation will be high enough that the pack can no longer charge to 117.39 kWh and we’ll start to see SoH decreasing.
As far as charging to 100% to rebalance cells for Lucid EV batteries (NMC), I can’t find a Lucid official source that recommends it. However, I have seen charging stall at 99% for a long period of time, which is characteristic of the BMS doing balancing. I’ll have to monitor the 99% charge rate as mentioned in
EV world on battery cell balancing. Does anyone know for sure?
