3 ms·
That would be a worthy trade, but that is vastly overstating the weight of aluminum block engines compared to Li+ and not at all realistic.
by willis936 3y ago
That would be a worthy trade, but that is vastly overstating the weight of aluminum block engines compared to Li+ and not at all realistic.
- Retric 3y agoAtkinson engines have poor power to weight ratio at maximum efficiency, if you’re going to maintain that 40% then the engine needs to be oversized and under utilized. This is why many hybrids have seemingly much more power than they need. Thus the 194HP Prius vs 75 HP on a CX-90 plug in SUV. Also it’s not just that you can have extra Li+ it’s also pushing around less dead weight when the engine is off. So you can get fairly close to a 50 mile range difference depending on exact setup. Alternatively you can have a smaller Atkinson engine and a larger reserve on the battery, but that also costs range while still being heavier.
- pfdietz 3y agoIt could make more sense to use a conventional engine, but get extra expansion (the kind an Atkinson/Miller cycle engine gets from the longer expansion stroke) by turbo-compounding. That is, exhaust gases (still at greater than ambient pressure) go through a turbine that is coupled to the output shaft, or to another generator, rather than being used to drive a compressor as in a conventional turbo. Or, attach a motor/generator to a conventional turbo and be able to have it operate in both modes and use the battery to help overcome turbo lag.
- Retric 3y agoPossibly, but that’s a lot of separate systems. It might make sense to look into a turbine engine on a hybrid. Though that’s probably been investigated I doubt anyone has invested the kind of time and money needed to make a real shot of it.
- eptcyka 3y agoYou will never be able to match the weight of a Wankel with a regular reciprocating piston engine, all other parameters being equal.