DC fast charging is throttled? EV

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Mechy

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Less than 6 months in, I've noticed the last few times that DC fast charging has been throttled much earlier. No way am I getting 80% in 30 min anymore. This is California, so no significant change in temps, or chargers (it's indoors anyway).

Is there a fast charging limit? Honda says no, but that seems like BS. I use DC fast charge regularly on errands, but less than once per week.

Anyone else have this experience?
 
Is the beginning SOC the same? Since you say on errands it seems like that might be a variable. Also possible it is an issue with the charger. Have you tried multiple chargers with the same result? Have you checked PlugShare to see if other users are experiencing issues?
Was this a unit with 2 nozzles? If the other was in use, many times it will cut the available power to both.
And a relatively small temperature change will make a difference, particularly if combined with other factors.

I've only used DCFC a couple of times. The first time was on a Greenlots unit starting with about 52% SOC in coolish (45 degree?) temperature and the power was similar (a touch higher) than your second graph. The other two times it was on a 150 kW EA unit and saw 41 to 44 kW until a small taper at 80% and another drop at ~90%. Started at 45% and 2% in ~65 to 70 degree temps.
 
Honda may feel that frequent fast charging is not healthy for the battery. There may be some algorithm that Honda uses that begins to throttle fast charging once you’ve done it a certain number of times. Some Tesla owners claim they experience it too.
 
Beginning SOC was close to, but not exactly the same. The SOC at which it begins throttling is not occurring earlier, although it's hard to note exactly when given that it's difficult to get that detailed info from Chargepoint or Honda, without me sitting during charging taking notes. From memory, tapering used to start at 80%, and now the taper starts near 50%.

The units have 2 nozzles (Chademo and the CCS) but one one can be used at a time. Same grouping of chargers.

I feel like what Ken7 mentioned is happening, but I haven't heard of ay other experiencing this.
 
Mechy, I think it's relatively rare for Clarity owners to be fast charging. That may be why you haven't heard of others experiencing it.
 
Unless you have tried a different DCFC (preferably on a different network and with different equipment manufacturer), it's impossible to say whether the Clarity is behaving differently or not.
If it exhibits the same behavior on a completely different charger, it is likely the car.
If it acts "normally", it is either the Chargepoint DCFC or something to do with the interaction between the charger and the car (Chargepoint L2 is notorious for intermittent issues with the Clarity and some other EV's, and possible their DCFC protocol could have some quirks as well)
 
I've only hit 40kw once while DCFC. Everytime I've tried it seemed to be capped at 25kw regardless of my SOC and drops to 20 or less at 75%+. My BMW did 50kw consistently until 85% SOC. A bit annoying when you jsut want a quick 30min charge to get home. I dont DCFC that often either.
 
Depends a lot on the amperage of the DCFC you connect to. The Clarity batteries are a nominal 311 V
325 V @ 125A is a touch over 40 kW, and that is about the max you'll get. Some "50 kW" equipment is 100A, so you'll top out at ~32 kW. And some of the BMW installations were 25 kW max.
The lower voltage of the Clarity batteries results in slower DCFC.
 
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