Page 1 of 1

REx Distance

Posted: Tue Jul 28, 2020 6:03 pm
by bstoneaz79
Looking into purchasing an i3 REx, probably 2015-2017, maybe a 2018 if I can find a great deal.

That being said, distance is my concern. I'm in outside sales so it isn't just a home-office-home scenario, and charging during the day isn't ideal.

My initial research appears I can just fill up the fuel tank and continue to drive while the REx charges the batteries. However, I went and spoke with a sales person at BMW today and he claimed the range is going to be significantly less than stated due to the AZ heat (at least in the summers) and I'm only going to get another 12-15 miles of range from the REx. The way he made it sound I might only pull 50-75 miles between the batteries and REx and the REx won't just continue to charge as long as I stop for fuel.

So, couple questions:

1) Anyone here drive one in AZ? If so, how's your range in the summer?

2) Anyone here rely more on the REx to get the distance you need or am I asking for trouble? Likely looking at 75-100 miles/day on average, but some days could be 150-200 miles.

I'll step to a true hybrid if necessary, and I'm not interested in a Tesla (service centers are so backed up in AZ it's 3-4 week turnaround for repairs).


Re: REx Distance

Posted: Wed Jul 29, 2020 4:54 am
by MKH
The original design premise for the i3 was as a city commuter car where the normal commuter rarely drives more than 30 - 40 miles a day. The REx option was put in place more to address the range-anxiety of the potential buyer than turn the i3 into a true hybrid. It's a 650 BMW scooter motor that powers an electric generator, put there as an occasional-use back-up power source.

I live in Texas, and think my i3 REx is great. Below 80 degrees, I get around 60 -70 miles on electric, depending on how 'aggressive' my driving is. Get into the 90 - 100 degree days, with the AC going strong, the electric range does drop significantly (the AC not only cools the cabin, it also cools the high voltage battery pack). Great car for me - I rarely drive more than 20 miles a day. Could you use it to drive 75 - 200 miles a day? Sure - in the full AZ heat, guessing 50 miles max electric a day (maybe less), then gas up every hour or so to run with the REx. Would I do it? No. As much as I like my i3, I'd be looking for either an EV with at least 200 miles range like the new Chevy Bolt (knowing on some days I'd still have to stop and charge for an hour or so over lunch), or a solid 'real' hybrid. And do you have the option of installing a level two charge station at home? With an EV and the miles you drive - a necessity. Trying to keep a high-mile EV 'fueled' using the current public charging infrastructure will be a study in frustration.

Can you write off your car as a business expense? If so, I'd be looking at something new, which will have the biggest battery, and a service warranty that will provide a free loaner when the car is in for service. With the slow car sales due to Covid-19, there are some great new car deals to be had - 70 month financing to keep payments reasonable, and very low interest rates. Otherwise, I'd be looking at a used Prius or similar.

Re: REx Distance

Posted: Wed Jul 29, 2020 11:05 am
by alohart
bstoneaz79 wrote:
Tue Jul 28, 2020 6:03 pm
Looking into purchasing an i3 REx, probably 2015-2017, maybe a 2018 if I can find a great deal.
A 33 kWh battery pack with ~40% greater usable capacity was included in 2017 and 2018 i3's. For your use case, I would avoid a 2015 or 2016 i3. Some of their smaller capacity 22 kWh battery packs seem to degrade more rapidly than the 33 kWh version. A minor update occurred in 2018 which includes some nice changes.

We have a 2014 BEV and have no experience with the REx version. I have read that the REx engine gets ~30 mph in unfavorable conditions, so with ~2 gallons of gasoline capacity, I'd be very surprised if the REx would add only 12-15 miles of range in hot weather.

Re: REx Distance

Posted: Wed Jul 29, 2020 11:10 am
by bstoneaz79
Thanks, MKH. Honestly I was expecting essentially the answer you gave after my trip yesterday and reading this forum more and more. Thanks for the advice on the Bolt, I've put that and the Volt on my short list.

Re: REx Distance

Posted: Wed Jul 29, 2020 1:05 pm
by jadnashuanh
Under ideal conditions, while using the REx, you'll likely get about 30-35 mpg, so maybe a maximum of 70-miles. As said, the REx drives a generator, the vehicle always runs all electric. When it's necessary for the REx to turn on (or before, if you enable it), it will still turn on/off under certain situations on its own, and the RPM will vary depending on the load. At the state of charge when it turns on is the maximum the REx will try to maintain.

IMHO, if you need more range than the normal battery capacity on a daily basis, an i3 is the wrong vehicle for you.

The newest ones have a much larger battery than the original, and if there are any local rebates, and if you aren't impacted by the AMT, the feds will give you a decent credit as well. At least with the federal credit, it only applies to new users. Combining all of the credits that may be available could dramatically lower your cost to just buy new, and then, you'd have the full warranty as well to take care of anything that may crop up.

Re: REx Distance

Posted: Fri Jul 31, 2020 9:27 am
by BL5
2015 REx owner here. I typically get 70 miles off battery and 70-75 off REx (coded my tank to 2.4g). For your needs a 2017 would work fine. 2017 would get you 115mi off EV + 70 off REx. Your AZ heat might kill 20-30% of those figures.

If you can plan your sales calls around some charging it’ll make it less stressful. I’m sure there’s some DCFC options for a quicker fill up.

Re: REx Distance

Posted: Fri Jul 31, 2020 4:47 pm
by jadnashuanh
If your normal day has you sitting in the vehicle with the a/c running while you do paperwork, your efficiency in AZ where it could be 115 in the shade, could be problematic on a typical's not just the miles you put on, it's the time the thing is functioning. Personally, I don't mind at all plugging in when I get home...takes only seconds, but would not be particularly happy having to stop and fill the gas tank daily. If you've really gotten your battery SOC down, and your sale was up a long hill, you also might end up crawling up at like 40-50 mph, as a 35 Hp kick from the REx's generator would make the vehicle about the equivalent of one of the early VW bugs...slow! I suppose you could keep a 10-gallon gas can at home and maybe get by with filling it once a week, and just fill up when you get home.

Note that the life of the battery is based somewhat on the number of charge/discharge cycles. So, if you discharge your battery nearly fully on a daily basis, along with the heat, your battery life may be impacted. One cycle is from 100-0-100%, and it's about equal to 10 charges from 90-100 and back. The larger your battery pack, over the same miles, the fewer charge cycles you'll accumulate, and the longer in time your battery pack should last. This all may become mute when SS battery tech gets here, but that's probably at least 4-5 years away. Toyota said recently, they expect 30-years life out of the SS battery they're hoping to get into the first cars in 2025, with only a 10% loss.

Re: REx Distance

Posted: Mon Aug 03, 2020 8:03 am
by JohnKelly
"moot" not "mute" :)