2012 Infiniti M35 Hybrid
Published Friday, 29 April, 2011 by Morgan Buonaiuto. Categories: New Inventory, Green, News.
The M35 Hybrid is Infiniti's first vehicle powered by Nissan's all-new, in-house-designed, full parallel hybrid powertrain, which comprises a 3.5-liter V-6 engine working in conjunction with a single electric motor and two clutches. Nissan will initially launch the new system in its Japan-market Fuga sedan this fall. We'll get it next spring at a price set somewhere between the M37x all-wheel drive ($49,275) and base M56 ($58,425), which is in the neighborhood of its main bogey -- the Lexus GS 450h ($58,325). Not surprisingly, it will also be Infiniti's cleanest ride ever.
As with all hybrids, the idea is to rely on electric power as often as possible; Nissan's technique employs the twin clutches to decouple the gas engine from the transmission, which shuts off the engine completely. This approach nixes the need for a torque converter and allows for the direct application of power to the rear wheels (the only drive layout) -- further aiding throttle response and acceleration. Nissan claims there is no mechanical drag when the engine is shut down, so the whole package remains efficient and clean. A specially calibrated ECU orchestrates system reactivity and fluidity, and regulates engine idle to reduce fuel consumption.
Scenario 1: Combustion Engine Off, Electric Motor On -- gradual acceleration, low-speed urban driving. First clutch disengaged, engine shut off, second clutch engaged. Motor drives rear wheels and uses power from the lithium-ion battery pack.
Scenario 2: Engine On, Motor Off -- mid to high speeds. Both clutches engaged. The engine powers the wheels, while the wheel motion and motor help the recharge the batteries. The gearbox's high final gear ratio also aids efficiency.
Scenario 4: Engine On, Motor On -- full acceleration. Both clutches engaged, while engine and motor power wheels. Batteries are discharged.
About those batteries: a lithium-ion battery pack generating 1.3 kWh is located under the trunk's floorboard (which of course compromises cargo space). The setup is structurally similar to that of the the upcoming Nissan Leaf, but is tuned specifically for fast charge/discharge properties versus all-out range. Lamination bumps up cooling efficiency, while the use of manganese positive electrodes stabilizes temperature.
Nissan says its setup is more efficient than Toyota's two-motor Hybrid Synergy Drive (like the one used in the Nissan Altima Hybrid and Toyota Prius), but no exact details were given since final fuel consumption and CO2 output have not been determined yet.
Lean into the throttle and acceleration is immediate and smooth; it gently jostles you back into the supportive throne. While the hybrid doesn't feel as quick as the M37 and certainly not as brisk as the 4.6-second-to-60 M56, don't throw this hybrid into the pile of boring gas-electric road machines just yet.
While cruising slowly, the hybrid system, with the gas engine on and the electric motor off, operates in near silence, the only in-cabin noise coming from the air conditioner. With the throttle applied lightly, the M35 Hybrid can operate under electric power at speeds up to 62 mph (for how long and at what point the engine will kick in wasn't revealed by Nissan engineers), which compares favorably to the Prius Plug-in Hybrid EV we've had at the office. Adding to its impressiveness is the seamless way the engine switches on and off when accelerating and decelerating.
The M Hybrid also employs a new electro-hydraulic power steering system -- another fuel-saving, world's-first technology. Power assist comes from hydraulic pressure and is controlled by an ECU and motor drive that operate only when steering assist is called for. As we felt during our short flogging, the helm proved smooth, weighty, and precise.
More often than not during the extremely quick test, the M35 Hybrid's engine was off and decoupled as a result of us being off throttle, or in some corners, traveling at low speeds. It's not always a good sign to see the tachometer needle pinned at zero while rolling fast, but this time, it's fine by us (the hybrid coasts on electric power and can regenerate juice at any speed if needed). When you do crave that extra grunt, the sleeping gas engine under your right foot is ready to awake in an instant. Further, the hybrid doesn't lack for sportiness -- hit a corner aggressively and it feels much like a sport package-equipped M37, plowing mildly but remaining tractable and collected.
When asked about a possible plug-in option, engineers on hand simply smiled politely and remained tight lipped. We wouldn't be shocked if the team in Oppama is indeed developing a similar setup, especially given the soon-to-arrive Chevrolet Volt and Toyota's Prius plug-in.
So while Infiniti may be fashionably late to the luxury hybrid party, this technology-stuffed, sporty hybrid sedan certainly looks as though it will be a green machine worth keeping on the guest list. Our notion of the hybrid/luxury segment has definitely been adjusted -- and it only took seven minutes.