Infiniti’s Electric Approach
As Infiniti celebrates its 30th birthday (which will be officially marked November 8), the company is looking forward to at least the next 30 years, with a clear understanding that one of the most significant changes that is likely to occur is the electrification of the vehicle. The company, like seemingly all others in the space, has announced that going forward it will be electrifying its portfolio, which means that some vehicles will have an internal combustion engine on board while others will be full electrics.
But the people at Infiniti also acknowledge that there are still some people who are leery for several reasons about going to a full-on EV (e.g., range anxiety). So they are going to provide those people with a means by which they can gain familiarity with what a fairly substantial electrified powertrain means so that there is more of a transition for them vis-à-vis a full EV rather than an all-or-nothing proposition.
According to Eric Rigaux, general manager, Product Strategy & Planning for Infiniti, “For three decades Infiniti has built a reputation for introducing powertrains that excite and empower drivers.
“Our new gas-generated EV powertrain represents the next step into our electrified future, acting as a bridge to full electrification and setting the tone of our upcoming zero and ultra-low emission cars. However they are powered, our cars will offer thrilling yet serene electric performance, and e-AWD systems which inspire driver confidence.”
The gas-generated EV powertrain is, in effect, a series hybrid. That is, there is an internal combustion engine that operates as a generator that charges the batteries, which, in turn, are used to power the motors that turn the wheels.
The Infiniti Q Inspiration and Qs Inspiration concepts.
The engine/generator in question is the MR15DDT. This is a variant of the VC-Turbo variable compression engine that the company has developed. In this case the MR15DDT is a 1.5-liter three cylinder; this will be the first application of this unit.
The variable compression occurs through the multilink design such that, for example, the piston connecting rods are nearly vertical during the combustion cycle (not moving more laterally than is the case in a conventional crankshaft setup), which Infiniti says is “the ideal reciprocating motion.” It also eliminates the need for the balance shafts that are typical in in-line engines.
The MR15DDT is on what is said to be a “world[‘s]-first independent mounting system.” This system, which includes fluid-filled mounts, minimizes engine noise and vibration.
The electric motors are going to be scaled depending on the type of vehicle. That is, there will be a total output range from 185 to 320 kW (248 to 429 hp). Because the wheels are driven by the motors, there is linear acceleration (no conventional “shifts”). The high-performance version will have the ability to accelerate from 0 to 62 mph in approximately 4.5 seconds.
Urban Emissions Addressed
Although there is considerable emphasis on performance, they’re also cognizant that there are emissions considerations, particularly in urban environments. When operating in lower speed city environments, where there tends to be greater emissions from an ICE, the MR15DDT is able to operate at lower speed because it is charging the battery, not turning the wheels, and therefore has comparatively lower emissions.
It is worth noting that Infiniti is undertaking a “two powertrains, one platform” approach that will accommodate both this gas-generated EV powertrain and fully electric powertrains. This will simplify production through the commonality.
For the full EV the space between the axles will be used to accommodate the battery pack; for the gas-generated EV, the space will include a smaller battery pack, the fuel tank and the exhaust system.
This transitional approach toward bringing people greater familiarity with what electric driving is like undoubtedly will help drive full EV tech forward for Infiniti.
Generally, when OEMs produce aluminum engine blocks (aluminum rather than cast iron because cast iron weighs like cast iron), they insert sleeves into the piston bores—cast iron sleeves.
Honda is an engine company.
The engineers at Munro & Associates have taken a perfectly sound BMW i3 and taken it apart. Completely apart. And they are impressed with what they’ve discovered about how the EV is engineered.