New Owner -- Battery/Charging Question

[Matt27]

I bought a used 2019 Honda Clarity with about 16,000 miles on it a week ago. I've charged it 5 or 6 times so far, and 3 of those times I charged from empty up to full. I don't have access to charging at home, so I've been using Level 2 charging at work and at public stations.

When I bought the car, the electric battery was empty, and I presume it had been sitting on the lot for a couple weeks. When I filled it the first time at a SemaConnect station, it said I got 14.1 kWh, which made sense since based on my research that seems to be about the usable battery. The second and third time I charged from fully empty, I got 13.6 kWh and 13.4 kWh. The second charge was at a ChargePoint station and the third was at same SemaConnect as the first one (but it was a different station at the same location).

On all 3 occasions, the Honda suspended charging when full and I picked up the car soon after.

Since I'm new to owning a PHEV, I wanted to see if this was concerning. I know batteries degrade over time, but this led me to a few questions:
1. Is it normal for the amount of kWh to fluctuate when charging from empty to full?
2. Is it potentially just that I'm using different stations each time?
3. Did I get more the first time since the car had been sitting empty on a lot for a while?
4. Is it bad that I'm regularly charging from empty to full? (I read that the Clarity limits the top and bottom end of the battery to avoid degradation, but do I need to manually cut off charging before it reaches full?)
5. Is there anything else I'm not thinking of, or am I just overreacting to normal fluctuations?

Thanks for any help anyone can provide. If I'm doing something wrong, I'd rather know now and fix it. Thanks!

 

[Robert_Alabama]

I'll give these a shot for you.
1) Yes, somewhat. I live on the top of a pretty big hill. I occasionally am running low going up the hill. I can "watch" the blue/white on the power gauge on the dash and limit speed/acceleration and drain the battery a good bit more without starting gas. If I don't "watch" the power gauge, I will start the gas engine every time before more fully depleting the battery.
2) I doubt it. I suspect the stations all record charging energy correctly.
3) Not sure about this one.
4) I'm a fan of driving and charging the car the way you want to. I don't think that actively trying to save/maintain the battery is worth the effort, but that is my opinion. I try not to leave my car fully charged for days/weeks without driving it, but that's the limit of my attempt at prolonging batttery life.
5. You might want to check the Ah capacity on the battery. You can do this with a Vgate ODBII Diagnostic interface.
Welcome and I really hope you enjoy your Clarity as much as most of us here do ours!

 

[Landshark]

We can only guess, but, #3 is probably a good guess. The battery may have been “more empty” at the start of your first charge.

I’ve pretty much stopped tracking any data on the car, not that I tracked that much initially. It’s good that you’re establishing a base line. I’d did that too. Now I just plug it in and drive it, or add gas and drive it. I’d think that some variation in total energy consumed during a full charge would be expected. Maybe some cell balancing occurred, maybe the DOD was a bit different, maybe the cooling fan and circulation pump ran a bit more?

I also charge until full and try to use as much battery capacity as possible. No “smart” charger, no Hondalink. There’s endless discussion about micromanaging the battery charging process on this forum. Not my cup of tea.

 

[Paddy]

I have the same model with about the same miles. I have got used to the variation between seasons and pay not much attention to keep track of the battery anymore.

 

[MrFixit]

Since I'm new to owning a PHEV, I wanted to see if this was concerning. I know batteries degrade over time, but this led me to a few questions:
1. Is it normal for the amount of kWh to fluctuate when charging from empty to full?
2. Is it potentially just that I'm using different stations each time?
3. Did I get more the first time since the car had been sitting empty on a lot for a while?
4. Is it bad that I'm regularly charging from empty to full? (I read that the Clarity limits the top and bottom end of the battery to avoid degradation, but do I need to manually cut off charging before it reaches full?)
5. Is there anything else I'm not thinking of, or am I just overreacting to normal fluctuations?

1. Yes, this is normal. The bottom limit can vary depending on what you were doing during and after reaching the limit.
2. I'm sure there is a tolerance on how accurately a charging station measures energy, but since you are paying for the energy used, it is likely a good bit better than this variation you saw.
3. Quite likely... The HV battery can be drained well below the normal lower limit.
4. Varying opinions... My opinion is to use the vehicle in a way that is convenient for you. Some argue that babying the battery can help extend life.
5. Relax... It is probably just fine. More time will tell.

If you really want to know the status of your battery, then you would be well-served to tool up to query the vehicle to obtain it's Battery Capacity.
See this thread:
https://www.insideevsforum.com/community/index.php?threads/budget-battery-capacity-readout.10531/

 

[Carro con enchufe]

My 2018 has about 43k miles and takes between 11.75 to 12.5 to fill up. Variation is normal and can depend on how empty the battery is, what the outside temp is, and probably other factors. I recommend just driving and enjoying the car without worrying about it.