> most modern hybrids use the ICE at higher speeds for efficiency, right? What does that mean in terms of added complexity and reliability? It really depends o

> most modern hybrids use the ICE at higher speeds for efficiency, right? What does that mean in terms of added complexity and reliability? It really depends on the type of hybrid in question. Those are series, series-parallel, or parallel. Some hybrids essentially just use an electric motor to assist in a traditional ICE-like drivetrain (parallel). This is the kind of setup you'll see in something like the Ford Explorer Hybrid or most of Honda's hybrid systems. In these cases, the electric motor just sits in the regular ICE drive train and supplies additional power especially in low efficiency ranges along with regenerative braking. https://en.wikipedia.org/wiki/Integrated_Motor_Assist https://en.wikipedia.org/wiki/Integrated_Motor_Assist In an e-CVT setup (series-parallel) like what you would find in a Ford Escape Hybrid or most Toyotas using a Toyota Hybrid System or Hybrid Synergy Drive, the overall mechanical complexity of the system is considerably less. https://en.wikipedia.org/wiki/Hybrid_Synergy_Drive https://en.wikipedia.org/wiki/Hybrid_Synergy_Drive