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Comment by jkterhune | Hacker News Reader

PHEV in the title is plug-in hybrid electric vehicle. Different from a pure EV.

This is true. EVs are much simpler than ICE, and PHEV basically have all the complexity of EV+ICE.

PHEVs mean that half the time your using your battery to drag around an ICE, the other half the ICE is dragging around a battery.

A very temporary phenomenon in the evolution from ICE to EV.

Probably the one type of PHEV that should survive is basically a BEV with builtin backup generator. One that's not necessarily powerful enough to drive you directly at full speed, but enough to basically eliminate range limitation of a (cheaper and smaller) battery by continuously charging it when needed. Maybe this 'backup generator' can even be made as a removable option.

I'm thinking of a semi-rural use case, when your typical daily trip is 20-50 km, but the charging infrastructure is poor and occasionally you do need to drive 200-300 km in winter.

Your phrasing implies this causes extra weight gain - just to illustrate, the new Prius is about 1.4t (while having decent PHEV range), while the ID4 (a similar sized EV) is 2t.

Plus more. My Volt had a component fail that was responsible for switching the cabin heater between the battery and the motor, so if I placed the vehicle in pure EV mode then I couldn't heat the cabin, oops!

PHEV means a lot of things. Toyota PHEVs with e-CVT are simpler than a normal ICE. VW PHEVs where there’s an electric motor tucked into their DSG gearbox - not so much.

And then the kicker. VW doesn’t allow the dsg with electric motor to be repaired by dealers. If something is wrong it needs to be replaced completely. At the cost of €15k (NL, 2021). The only serviceable thing is the clutch and the mechatronic.

IMHO this is something that should be regulated away as consumer unfriendly and environment unfriendly. (Not to say hostile.)

In the end I got a DSG specialist fix the problem in two hours by replacing two simple components physically. The car then spend an hour retraining the dsg.

Does that make a difference in this regard? If so, how, and is it an unavoidable penalty for PHEVs? I can see PHEVs having a complexity penalty from having an IC engine over and above the EV components, but that does not seem to be the source of the problems here.

Well designed PHEVs can actually be simpler than pure ICs (at least on the hardware side. To build a combustion only car well, you need to balance efficiency, power, and responsiveness. This means you need all sorts of complicated tech, like correctly sized turbos, variable valve lift, variable valve duration, etc. In a PHEV, otoh, you have an electric engine (which can also steal power from the driveshaft), which means you don't need to worry about responsiveness of the combustion engine. You can fill half a second of turbo lag with the motor, and optimize for narrower RPM ranges since you can charge/discharge the battery to keep the engine running in its happy place. You also no longer need fancy and complicated brakes because you can do 99% of your braking with regen.

All of this does come with more complex software, but the hardware can end up with significant simplification.

I would say so for this particular failure.

The issue in this case has everything to do with the electronics design and close to nothing to do with propulsion.

The issue described is happening because German car makers love to put generic parts inside proprietary modules that cannot be repaired, and require extensive OEM tooling to replace. This kind of dumb shit happens on ICE cars and EVs that follow this design paradigm.

As described int the article the actual failed piece is ~$50 if you can replace just that pyrofuse. BMW doesn’t allow tha though. So you have to replace the entire module

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