Do I have to charge my BMW i3 REX? #bmwi3

The BMW i3 Range Extender is one of the weirdest and best electric cars you can buy!

We interview Andy Sue from Toronto Canada to better understand the Range Extender.

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[clasqm]

My 2015 i3 developed a charging problem (kinked cable, common on early models) and I rode on the REX for two weeks before I could get it to BMW to fix it. So yes, it can be done. It's financially a bad idea, though. The best thing to do with any EV is to charge it in your garage at night.

[briancollins]

I've been looking for the answer to this exact question for a this is the first video to talk about it. Thanks!

[DaveDarin]

I just tested this out for you guys. I drove my 2020 i3s REX from Pennsylvania to North Carolina and then North Carolina to Arizona. I put on 4000 miles in total with these trips plus random driving. The onboard GPS allows you to find charging stations between the total distance and insert the located charging station as an intermediate stop. I prefer using Electrify America and there are often charging stations that are not available. In 2 states, in particular, it seems they are less supporting of electric Oklahoma and Arkansas. So I would drain the battery to 35% remaining charge and then run the gas generator. Yes I hacked the software to allow me to turn on the REX at any point below a 75% charge. At one point, I think it was in Oklahoma after I drained the battery to 35% I was at 30 miles left of gas, so I refueled a second time. You do have to be careful because if you are going 75mph and it’s an uphill climb and the AC is on the REX can’t keep up with the demand. At one point with the REX on, I still lost 3% of my charge. Of course the uphill meant an area of 7% downgrade and I actually regained 1% back due to regeneration. So if you don’t hack the REX and allow the REX to auto kick on once the battery is at 6% then that’s pretty dangerous since any uphill and high speed demand could bring you down to less than 6%, I could have been down to 3% battery with plenty of gas. I think what you might have to then do is pull over and let the REX recharge to 6%. With no demand and pulled over I think the REX will recharge to the 6% or to the level in which you hack the software and turn the REX on. In other words I turned the REX on at 35% charge and with the high demand I dropped to 32%. I think I could have pulled over and the REX would recharge to 35% but it will not keep charging beyond the 35%. Think of it as a marker. When the REX is engaged it knows the charge that was remaining and it will maintain the battery to that level. If the demand exceeds the REX capability it will recharge when the demand drops off but only to the maximum level of the percent the battery was at when the REX was turned on. I always had, in the back of my mind, Will I get a message that the REX could not be turned on during my 4000 mile trip? I probably turned the REX on about 10-13 times during my trip so I did worry that the car might complain about that. I did charge more often than I needed to when charging stations were closer and sometimes I charged at the next station with 60% battery. More stops doing it that way but you still have to wait either longer to charge from 30% or shorter but more often if at 60% as the car seems to always charge at 48kW. And the charging stations say that charge speed will slow after 80% charge but it still dies well to 90% charge. Beyond 90% it slows and by the time you hit 95% charge you will be charging at a rate of less than 20kW or slower so I only charged to 95% then I left. Was not so bad for me as I traveled with my dog so we walked while charging. Would I do this again? Maybe but not for a couple years, but I am planning a vacation in 2 weeks from Arizona to California which is 388 miles where i will turn in the REX at 35% but that’s much easier than 4000 miles.

[rogerhudson]

BMW says the idea REX speed for recharging is 90 kph/ 56 mph. You can reprogram the car to let the driver switch on/off the REX at about 60% charge and hold it.

[andysue]

“Don’t worry about range anxiety it will go away.” I was told in the beginning and it’s true, and it’s even easier to get over it in the BMW i3 REX 😉 Just keep striking us with these bolts of information 😃

[sunfy]

I actually tested this concept for about three days, approximately 120 miles. During this period, I didn't charge the i3 and purely ran it using the generator. Didn't notice any speed or torque deterioration. My 2 cents..

[andrewamidala]

Had mine for over a year now a 2016 rex and I don't have anything bad to say about.
The 12 volt battery went but this was easily replaced at Wisley in the UK (About £180 with programming).
Have to change all tyres but about £600 (about the same as my Jag).
I was going to go with the ipace but very happy with my i3.

[TheNikitaKalyuzhnii]

00:03 Charging the BMW i3 REX is essential.
00:55 Using gas in the range extender can charge the battery, but not recommended regularly.
01:48 Using the range extender for the BMW i3 REX
02:40 Driving the BMW i3 REX at night without needing to charge
03:22 Battery dropping below 6% puts the car in limp mode.
04:08 BMW i3 REX eliminates need for gas station visits
05:06 Driving the BMW i3 REX while making sacrifices in eco mode.
05:55 Misconception about using range extender without charging

[whocares]

i have a bmw i3 rex, great a proper ev (the gas engine is only a generator) with no anxiety, but people say don't run on the generator all the time it is not recommended but why not?

[justiceg]

sounds like he's talking about running the range extender at the US standard 6% charge rather than 75% which shouldn't hurt to run continuously

[DemaGeek]

Great video on an interesting car, thank you!

[speculativeauthor]

No. You can set the rex in settings to maintain level under 75% charge and add fuel instead of charging. Not all the time.. but for trips.

[phatmeow]

can someone make an in car video of how the sound of that extender is like when it kicks in?

[johnwebsterification]

Better to jailbreak the car to European standards. You can run on REX with full battery. Also can use more fuel.

[richardchristian]

Code it to add " hold state of charge" and she can start the REx at 74%. Then she can run the car any speed she wants and would take forever without hitting 6%

[raymaas]

Also you'd be constantly stopping for gas because of the absurdly tiny gas tank.

[TheAlanSaunders]

I find it hard to believe that anyone in North America has adopted this overpriced ($50k?) toy car! In Europe it has a slightly larger fuel tank (2.9 l rather than 2'.7 l) and the REX can be engaged at 70% battery power thus the illegal (?) modifications to European specifications.

My UK '07 Clio 1.5 85hp DCI goes 700 miles on a 55l tank (14.53 US gallons)! New price from £15K but Renault is not available in North America. There are European and Japanese 'Supermini' and even 'family sedans' available in NA with excellent economy. I fail to understand why your expensive hobby is to prove that this expensive to buy and disastrously expensive to maintain BMW i3 is the future of motoring?

Even a s/h BMW i3 is not cheap; they have endless problems that could cost you another $3.5k to correct. I forgot to mention the expensive, peculiar mix of sizes for front and rear tyres with only three suppliers! Forget the 10K front, 40K miles rear tyres on a typical European Car; new BMW i3 tyres start with 3mm of tread; just when I replace mine!

[gregmccarter]

The engine in it is specifically throttled down to ensure long lasting..in the motorbike its 71HP