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Comment by Tade0 | Hacker News Reader

> Hybrid-electric cars are an engineering abomination. They have both gas and electric powertrains, ensuring they are more expensive and complicated than their competitors.

The latter is actually false. Having a high-voltage battery on board means you can get rid of most of the belts which normally power things too large for the 12V battery to handle, like the A/C compressor, power steering etc.

Same goes for the powertrain - no need for a typical gearbox when you can just replace that with a planetary gear.

Overall hybrids have less mechanical parts than regular ICE vehicles.

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Theres also the mild vs serial vs parallel hybrid thing.

Early hybrids were a standard ICE with some help from an additional motor, later hybrids moved towards being a BEV with a smaller battery that gets topped up by a generator (which is roughly what a hydrogen Fuel cell car is too).

This is analogous to what the article suggests with the Schneider drive.

But I think emprically, even the earlier mild hybrids were more mechanically reliable than ICE equivalents. Makes sense as you'd be in the sweet spot for the engine more often.

In bike terms that is the equivalent of the amount of battery you need to get you over big hills and maybe help you get going from a standstill and maybe let you get away with a few internal gears.

> later hybrids moved towards being a BEV with a smaller battery that gets topped up by a generator

Aren't these cars usually sold as BEV with a range extender instead of hybrids?

A lot of them still have an ICE powertrain unfortunately

Well there's all sorts of different marketing terms.

Nissan seems to brand theirs as "e-power" to avoid geting them confused with their actual EV range, but possibly the lack of plug is the key difference there.

You need independent motors to run all those things after you removed the belts. You don't save any mechanical complication that way. Those components are now just electrically-driven from their own motors rather than mechanically driven from belts.

> You don't save any mechanical complication that way.

Actually, you do if you count the moving parts. A belt is always at least two pulleys and a belt. A motor is a motor. One moving part vs three.

In some cases you don't need anything at all - hybrids don't use alternators, some (like Toyota's HSD) don't even have a stepper motor for throttling and a dedicated starter motor - the two motor-generators perform this function.

Well, I guess 'it depends'. Generally I agree with hybrid systems being more complex that ICE only systems, but having a high(er) voltage electricity source and powerful electric motor available does remove some complexity.

Depending on the setup, the hybrid electric motor also acts a the starter, and generator for the ICE.

The hybrid drive may be used to move the vehicle in reverse direction (depending on how the hybrid system is implemented), removing the need for a reverse gear.

Electric power steering can powered directly from the hybrid battery, simplifying the steering rack.

So it does remove some complexity, but from an engineering point of view, I still think they are just too complex. Manufacturers just should give their customers the option to have full electric models, or fully ICE powered for those living in very remote areas.

After having driven some of the supposedly latest and greatest hybrid powered Lexus models (AFAIK Toyota is still king of hybrid drivetrains) I am not convinced. They drive nice, but would have been better if they were fully electric. I just cant believe how badly Toyota missed the EV market.

There are a lot of new Toyota models slated for release this year. By December, I wouldn’t be surprised to see them leapfrog Hyundai and Volkswagen if they can get parts and production stays on schedule.

I also think some of these automakers are riding a fine line and trying not to cannibalize the final years of the ICE lineup. Notice how many sporty driving cars are being released the last 2 years. It’s very likely those cars will be illegal to sell in a decade. It makes sense for them to produce those cars now and get a sale while they keep working on battery and range in a lab behind the scenes.

The key to that balance though is to actually put in the R&D so when they do decide to pump out EVs, they’re competitive to the market. If Toyota and Honda are playing catch up releasing 200 mile range EVs while the early adopters are moving on to 350+, then that will be the beginning of their downfall similar to the big 3 in the 80s.

You relax the location and orientation constraints on the satellite systems. No longer do they need to have a pulley in the plane of the rest of the belts. You may be able to eliminate or improve the reliability of seals now that you don’t need to take rotating power in. You can design for optimum RPM rather than having to accept varying RPM (possibly 0) scaled to whatever size constraints the pulley packaging limits you to. You can use electronic controls instead of electro-mechanical clutches. You can have these systems report status and take control instructions over CAN.

All of this in exchange for adding over-current protection, some wire/connectors, and some kind of control mechanism (typically relay or IGBT).

> Overall hybrids have less mechanical parts than regular ICE vehicles.

And free bonus: they almost certainly have regenerative braking, so you probably won't find yourself with a car with a small engine and no engine braking worth talking about.

Regenerative braking is specially dangerous in wet/snow conditions.

In teslas it’s even worse because it’s the rear wheels that brake the most. It’s like pulling the handbrake on the wet highway.

But it’s ok they have it as a warning in the manual “ Warning In snowy or icy conditions Model Y may experience traction loss during regenerative braking.”[1]

So no liability for the company. It’s now the driver’s fault.

[1] https://www.tesla.com/ownersmanual/modely/en_eu/GUID-3DFFB07...

.......... isn't the Model Y AWD? Why isn't regen braking performed on the front wheels where having more brake force makes sense?

Because range numbers are more important than driver safety

Could the complexity be reduced further if the hybrid moved to a fuelcell + electric motor instead of ICE + electric motor?

Effectively yes; the fuelcell itself is less complicated than ICE (well, probably not today, but it feels like that's an issue of one having been mass produced in incredulous quantities for a century and the other just barely out of the labs), but they both just make a disk rotate, effectively.

You could have an energy "cache hierarchy" in a vehicle.

Fast but small - capacitor

Medium - battery

Slow but large - fuel cell

Of course it would be quite expensive to build such a complicated car. Rather probably just a big battery will provide a good enough compromise. It might make sense for some very high use rate vehicles like buses or trucks. The capacitor could store energy for one accelaration from standstill to 30 m/s. (Or storing that braking energy). Batteries and capacitors get better every year too, so the tradeoff points are moving. For the fuel cell you could use power paste. It's much more expensive than electricity and requires special infrastructure, but it could be fast to fuel which could be a good tradeoff in some situations.

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