Before I do NAIAS… Honda could be called “He-Who-Ruins-Hybrids” from recent history. Yet they seemingly “nailed the formula” with 2014’s Accord Hybrid and Plug-In Hybrid. This, despite screwing up the ’06 Accord Hybrid; I tried a New Insight too, and was very unimpressed. The current (heh) Accord Hybrid is being compared to the Ford Fusion, called the smoothest and best-engineered 2013 hybrid (despite being a big sedan, not an econocar).
If imitation is the sincerest form of flattery, then it’s the Chevy Volt that should be proud. BMW poached Chevy’s staff for their plug-in hybrids; the 2014 Accord now takes a page from the Volt too. While the Volt certainly has its issues, it now seems to me GM got the concept down, but whiffed on some details. Honda, with the hindsight of a second (or third or fourth) mover, sounds like it now got the details too.
Like Chevy and Ford, the Accord has a battery pack and 4-cylinder gasser. Unlike them, the 2014 Accord sounds simple and mostly straightforward:
- At low speeds, a big electric motor pushes the car (“stealth mode”)
- At middling speeds (<43 mph), a small electric motor starts the 4-banger, then reverses polarity and acts as a generator to help feed the big electric motor
- At high speeds (>44 mph), the gasser engages the wheels directly; electric motors just hybridize, to smooth out the power delivery
The beauty of this layout, aside from electric torque I’d say, is that there’s no “transmission” and now just one clutch, between the gasser and the wheels. As a former gasser bike owner, I hate clutches. Did I mention I hate clutches? I frickin’ HATE LAGGY, LOSSY, SHORT-LIVED CLUTCHES. Deep breath, deep breath.
Digging deeper, the ’14 Accord offers stealth mode- the New Insight didn’t, a decade after the Prius had it. I consider that a bare minimum; no point in constantly restarting a piston engine in stop-and-go jams. The big electric motor is powerful enough to actually drive, unlike the Civic and Insight Hybrids, and with good pickup. With the Plug-In Hybrid, the battery pack is larger (6.7 kWh), so stealth mode takes you further. (Honda also gave it a 6.6 kW charger, so “refilling” isn’t much of a time waster. You could recharge while at a sit-down restaurant.)
Now, imagine accelerating. The gasser now fires, adding more oomph. This lets the battery pack be smaller, lighter, and cheaper. BMW does this with the i8, and Porsche’s hybrids do, too. (But not the Chevy Volt, nor the BMW i3…) Yet, the Honda isn’t connecting the piston engine to the wheels (yet); nor does the BMW i3, and in some cases the Volt. This saves a transmission in the usual sense; only wires connect pistons to wheels. Transmissions (and their associated clutches/torque converters) never add power or range. They only add lag, create friction, waste power, and demand maintenance. They also eat up volume, budget, and mass. If you have a chance to eliminate some or all of a transmission, I’d say go for it.
Now imagine accelerating further. At 44 mph on level ground, the gasser stops being a generator, and turns the wheels directly, by engaging a clutch pack. And when I say “directly,” I mean it- there’s one gear ratio, with no further shifting. The need for more shifting (and lag, friction, waste, etc.) has been eliminated through multiple fronts:
- Cages need low gear to push their bulk from a stop. Here, “low gear” is the prior 2 modes
- Most piston engines have narrow powerbands; Honda adds VTEC valve adjustments, widening power and reducing shift needs
- If necessary, the electric motors can pitch in to broaden the net powerband even more
The Volt doesn’t do this, really, though it has two gasser modes. The Volt’s 4-banger usually operates as a generator, helping out its larger battery and stronger motor. Rarely, it turns the wheels directly at certain magic speeds. The Volt’s gasser was finely tuned for only two speeds, “regular” and high rpm. Thus, the number and occurrence of magic speeds is pretty low and rare. The BMW i3 never couples its range extender at all; it’s purely a generator.
You may be thinking the Volt and Accord still sound alike. Both eliminate heavy, costly, friction-producing, service-needing transmissions. Yet, the Accord does it all with one fewer clutch- did I mention I hate clutches? The Accord also makes better use of its included gasser; while Volt (and some i3) owners are dragging around a full electric motor and pack, AND a complete piston engine system, the Accord has a more logical split, with arguably less waste.
Of course, the Plug-In Accord has a lower battery capacity than the Volt, and thus less gas-free range and power. As in 2013, the Plug-In Accord will only go a claimed 13 miles on electricity alone. If you live farther than that from work, then a Volt would probably save more gas (aside from being a smaller car to begin with). Hauling a cold engine to work is a small price to pay. The Volt’s larger electric drive (and smaller bulk) also means you could take highways and all arterial roads on electricity, where the Honda would start and stop its gasser.
The choice of power split is subjective, of course; Americans tend to commute by car farther than Japanese, so I expect a GM hybrid would go further stealthily than a Honda. And as batteries keep falling in price, automakers will continue to refine their power splits and range tradeoffs, likely toward less gas. If nothing else, a 2nd-generation Volt’s coming. After Honda got their act together and released a viable competitor, GM should be working hard on their response. It’s pretty sure the next Volt will have a smaller gasser, maybe an inline-3… and maybe a smaller pack. GM may move closer to Honda, just like Honda moved closer to GM.