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Then the board of directors chose a new CEO who decided to go ICE/diesel only.

We traded in a '25 miles of electric range' Prius Prime and kept the 72 miles of BMW i3-REx electric range.

The material is less important than the weight. The carbon fiber body on aluminum frame works great.

The BMW i3-REx has no mechanical link from the ICE to the drive wheels. On the highway, it works like a serial hybrid with a substantial battery buffer.

Checking eBay, the first listing was for a used, 2015 BMW i3-REx with 44,000 miles for $20,000. Better than our 2014, the 2015 model has improvements.

Bob Wilson

 

In 2021 bmw group world wide sold 4.1% bevs and 8.9% phevs or 328 thousand plug-ins. 2022-2025 will greatly increase this percentage as new plug-ins are introduced.

The problem for the i3 was price and form factor but it did well in 2014-2019. Then sales dropped a great deal. They did sell 250 thousand i3 between 2014-today.

That made perfect sense for your family. I doubt you would have bought the bmw i3 new though it was the used price that made the deal.

The problem with the material is cost. BMW got the cost of carbon fiber to drop quite a bit but could not get it low enough to work on a city car. With their expertise in suspensions and the regenerative braking, weight is less important in a bev than aerodynamics. My bet is the bmw i4 (bmw's answer to the tesla model 3) drives much better and has 300 miles of range despite weighing 1400 lbs more.

They could redesign with steel, use a less expensive atkinson 3 cylinder (maybe borrow the 1.5L from the yaris hybrid) strech it a little and adopt the body for better aerodynamics, and have a lower priced vehicle with all the good atributes.

 

But the i4 is only about a year old.

As you said, the i3 was an experiment. Conceived when battery costs were higher, so weight cutting meant more range per kWh. I brought up the Euro-centric design to explain why the short gas range. Europe doesn't have much of a road warrior culture.

It also let BMW show off their carbon fiber expertise. Doing the full body may not be cost effective for the lower price ranges, but CF can used to replace some parts. It got Toyota's attention.

 

The BMW i3-REx has no mechanical link from the ICE to the drive wheels. On the highway, it works like a serial hybrid with a substantial battery buffer.

Neither does the Chevy Volt; it's not a hybrid - it's a BEV w/gasoline generator. As I stated earlier, BMW i3 concept was copied from Chevy.

 

The short range was from California's BEVx regulations. No reason other than that to not have a 6 gallon gas tank.

i4 and ix are both new. BMW seems to think this short run customers will be fine with bevs or shorter range phevs.

Battery and electronics from the i3 live on in the mini electric.

Mini Electric (2022) Review | CAR Magazine

As I said they experimented and learned what they could.

The 7 series and ix both use carbon fiber along with aluminum and steel in their body. This saves some weight and adds some structural elements. It is not as expensive as doing a full carbon fiber body hopefully that lowers insurance rates.

 

My source: https://en.wikipedia.org/wiki/Chevrolet_Bolt

The Koreans must have used their time machine to design and release the Bolt in 2016, about two years after my 2014 BMW i3-REx came out. <GRINS>

Regardless, if you think the Bolt is a better, serial hybrid than the BMW i3-REx, no problem from me ... nor interest.

Bob Wilson

 

The original volt concept was an efficient 3 cylinder generator. They did not have a proper engine in their parts bin and did not want to buy from another company, so they used an existing 4 cylinder. To get their highway efficiency up they connected the engine and generator to front axle though a psd. It is slightly different than the prius prime implementation, but similar in operating characteristics with clutches to allow it to operate as a pure generator detached from the wheels.

The concept made sense so no problem with bmw implementing it after gm decided to go a different way. BMW also did not have a proper engine in their automotive group, so they borrowed one from the motorcycle group. BMW does now have a proper 3-cylinder rex engine in its mini lineup, but toyota has a better one in the the hybrid yaris. If bmw does it again I would hope they would use that or something like it. Toyota uses the excellent bmw turbo inline 4 and 6 in its supra.

 

I just can't see how it could be described as a Volt copy. The BMW is far better as an EV, while the Volt is far more useful as a hybrid. They are clearly aimed for different markets.

 

How I thought the Volt was going to operate is how the European spec i3 does, with a generator sized a little less than meeting all the car's needs. You turn it on when you know you will be exceeding the EV range that trip.

The Volt ended up being a power-split hybrid that could stay in EV mode in all US traffic.

I can't say if the gas tank could be larger, but it is the same size in both the US and Europe. Like the hybrid operation, the tank size is limited by software to have a shorter gas range in the US.

 

You misrepresent the Volt system. Here is GM's short description, which shows a direct mechanical link from ICE to drive wheels in 3 of its 5 modes:

Gen 2 Volt Transmission Operating Modes Explained | GM Volt Forum

 

He said Volt, not Bolt.

 

Was that the one that was canceled?

Bob Wilson

 

volt was the hybrid, cancelled. bolt is a bev, not long for this world

 

Yep, the Volt was discontinued.

 

Eventually to be replaced by the Equinox and Blazer EVs.

 

that would be good, bolt is too small. i hope they can pull off something that sells well

 

I think the official Blazer EV unveiling is in a week.

 

Under some conditions, the Volt's ICE does effectively propel the vehicle.
It raises efficiency, there was no real advantage doing by the concept, GM got it, fortunately.

Both i3Rex and Volt are plug-in hybrids by SAE classifications.

 

As there are different ways to do a hybrid, there are different ways of doing a PHEV.

The Volt was an EREV. The design prioritized EV operation with longer EV range. It could operate in EV mode up, and past, the legal speed limits in most regions.

The REx takes that EV favoring further. Most are a BEV with an add on generator. The engine can't supply enough power for full operation. I believe the i3 could do maybe 75mph on level roads. Power needs beyond what the engine can provide means needing energy in the battery. In the US, the need for CARB ZEV credits put further limitations on engine operation that hurt the REx concept and consumer.

How exactly the hybrid system works doesn't matter to the above PHEV categories. What our examples ended up with came down to what was practical. The i3 was a BEV. Adding a series hybrid system is a lot cheaper than developing a separate drive train for the REx version. The inherent inefficiencies of a series hybrid become a liability at higher speeds. The Volt's targeted EV range was shorter than BEVs available at the time, and GM possessed the technology, so the car was made a power-split hybrid for better highway efficiency when operating as a hybrid.

Most other PHEVs are blended systems. The car can turn on the engine for power when needed. When exactly that happens varies between models. Blended PHEVs are like mild hybrids. There is a wide spectrum of design that covers the category.

 

Owning a 2014 BMW i3-REx, I would add that the modified, two cylinder, liquid cooled motorcycle engine was not aggressively optimized: (1) no Atkinson valve tuning; (2) no recirculated exhaust to intake manifold, and; (3) no use of hot engine coolant for cabin and battery.

My practice was 70 mph with ICE driving generator.

Bob Wilson