BMW has sold the i3 since 2013, and up through last year, also sold the Range Extender version world wide, but now only sells the “REX” in the U.S.
The REX version adds a small engine in the rear, which powers a generator, making this a hybrid. In the U.S. version, the generator kicks on when the battery falls below about 6.5% remaining charge. (Hackers have provided tools to modify this so REX can be turned on at about 75% or less charge.)
This article is about a lawsuit over the 2013-2016 REX version of the cars, complaining of a power reduction when the battery reaches 6.5% and the REX kicks in. Sort of like “Duh”, that seems by design.
Source: Angry BMW i3 Owners Claim Range Extender Problems | CarBuzz
Where I live, the public charging network is limited – its over 100 miles in all directions to a fast charger, and in 2 of those cases (South at 195 miles and East at 120 miles), there is exactly one charger available. If there’s a line waiting, that won’t be a fast charge …
A hybrid solution like the REX is reasonable in the western half of the US where it will be some time before there is a robust charging network off the Interstate highway system. BMW recognized this and this is why they continue to sell the REX model only in North America (and Japan).
Mazda is planning to create a hybrid EV using its Wankel rotary engine technology as a range extender. Interesting!
EV purists complain that putting any combustion engine in an EV is stupid and defeats the purpose. Purists tend to live in California which has about half of all EVs and 1/3d of the entire country’s charging stations. They are living in a place that is not representative of the rest of the world – and there is place for PHEVs for years to come until EV technology has advanced further and charging networks are more robust. Most PHEVs are likely to do most of their driving in EV mode anyway; having the hybrid REX enables someone to use that car for less frequent long distance trips.