Two questions from new i3 owner coming from Leaf

[FergusH]

I picked up my i3 REX yesterday and this afternoon I've been sitting in the car going through the manual. A couple of things have me confused:

The first is how to configure charging. I came to the i3 from the Leaf and its setup was simple:
1. I had it configured to charge only between 9:30 PM and 8:30 AM, during off-peak hours. (I use PG&E's time-of-use rate plan.)
2. If I needed to charge immediately, I'd park the car, turn it off, and press the bypass timer button.

The i3 is a little more sophisticated and I've not yet figured out the correct setting. How would you recommend I duplicate what I was doing with the Leaf?

The other thing I don't understand is charging time. My i3 was mostly flat today when I got home. I plugged it in to a Clipper Creek LCS-25, which has a 4.8 kW delivery rate. The status screen reported that the i3 would be fully charged in about five-and-a-half hours.

That seems too long. If I divide the i3's 18.8 kWh battery capacity by LCS' 4.8 kW delivery rate, I get a charge time of a little less than 4 hours. What am I missing here? It's not a big deal - I usually charge by car over night - but I'm curious.

So far, I'm loving the i3; it's a nice upgrade from the Leaf.

Thanks!

 

[jadnashuanh]

Low cost charging works when you've set a departure time. It's an option while doing that, at least from the app. Since I do not have off-peak charging, I've not played with it much, but there are threads here that do discuss it along with some of its quirks. There may be other ways to activate it.

When setting a departure time you also get the optional advantage of both preconditioning the cabin for comfort AND preconditioning the battery pack for maximum functionality and range. There are three menu entries you can use to set departure times, maybe weekday mornings, then afternoons assuming your schedule is fairly fixed, and one for the weekend. Each one can be set for 'once', or any set of days. Note, one thing NOT in the manual is that to get the full battery conditioning effect, your departure time must be over 3-hours from when you set it. Warming up the nearly 500# battery pack takes awhile. Also note that if your whole system is warm, the car will likely spend some time and energy cooling or warming it up first, and that also takes some energy.

There is always some overhead when recharging the batteries, and the guessometer tends to be a little long, at least when you first start things up. Sensing the actual battery current charge state is a guess compounded by changing temperatures. Keep in mind that the onboard charging circuits in the i3 are larger than even the optional unit in the Leaf. So, with the heating/cooling/overhead, you'll always end up using more energy than apparent from the actual energy used while driving.

 

[BrianStanier]

Also there are losses in the charger and the battery when charging. A full charge needs around 21kWh. And the charge tapers off when the battery is nearly full. So it takes longer than a simple calculation suggests.

 

[jadnashuanh]

One thing came to mind...setting a departure time, even if you have a low-cost charging window set, may also mean you'll see some moderately extensive power usage outside of that window. On a really cold day, I've seen mine calling for about 20A when conditioning things, so depending on when you set that, verses when your low-cost window is set, if there isn't an overlap, you'll be using power outside of that window.

And, if you plug it in when the battery is quite low with a low-cost window for charging...the car does put some charge into it before that window for self-preservation (a low or dead battery isn't as safe in a cold environment). There is a reported bug in the software that says it does not always stop at the point after putting a bit in and then wait for the window. So, the car is juggling a bunch of things: temperature, low-cost window, current battery SOC, departure time (remember, that can take up to about 3-hours if it's really cold out or may not need to do anything if it's a nice day).

 

[getakey]

^ someone else reported a bug in the Departure time charging
have you experienced the bug?
Would hate to set window/departure time and not have car charged all the way

 

[jadnashuanh]

^ someone else reported a bug in the Departure time charging
have you experienced the bug?
Would hate to set window/departure time and not have car charged all the way

I don't have access to tiered power pricing, so no, I have not tried it. Use the search function and you can read other's issues.

 

[getakey]

I don't have tiered rates either but was thinking of switching

let me see how well Search works

 

[I33t]

The other thing I don't understand is charging time. My i3 was mostly flat today when I got home. I plugged it in to a Clipper Creek LCS-25, which has a 4.8 kW delivery rate. The status screen reported that the i3 would be fully charged in about five-and-a-half hours.

That seems too long. If I divide the i3's 18.8 kWh battery capacity by LCS' 4.8 kW delivery rate, I get a charge time of a little less than 4 hours. What am I missing here? It's not a big deal - I usually charge by car over night - but I'm curious.

Having charged mine quite a few times I have noticed that the actual charge time is less than indicated when I first plug it in. I haven't kept a log, but the difference can be hours.