Ram Deploys Unique Air-cooled Motor-Generator System

Bozi Tatarevic
by Bozi Tatarevic
ram deploys unique air cooled motor generator system

Earlier today, we found out that the 2019 Ram 1500 will be offered with a mild hybrid option dubbed eTorque. Official fuel economy figures are not out yet, but FCA estimates the hybrid system should show around a 10 percent improvement over current figures. The system employs a motor-generator driven off the crankshaft that is similar to the GM BAS system in some ways.

The novel part of the Ram system is that it does not require liquid cooling on the V8 version and is instead air-cooled, which should reduce costs significantly.

The motor-generator is mounted in front of the intake manifold on the eight-cylinder version and runs off the crankshaft via an eight-rib belt that is similar to something you might find on a supercharged engine. The traditional belt tensioner is replaced by a high pressure unit that is very similar to the one used on the GM BAS system and will likely require a hold-down tool for belt removal. The 48-volt system feeds power to a small 0.3 kWh NMC battery pack mounted on the back wall of the cab.

One major benefit of this type of system is that it fits in the same space as a traditional alternator, so packaging is not significantly affected. Air-cooling takes it a step further, since it eliminates coolant lines that would have to be snaked around the engine, and it reduces costs at the same time, allowing for a wider range of deployment. The motor electronics appear to be contained fully on top of the motor and covered by an aluminum heatsink; the only external connection is a single harness that runs back to the battery box.

The air-cooled motor was developed by Magneti Marelli, according to a patent application filed in November. The application states that the system employs a shaft-mounted fan that is internal to the motor case, which works in conjunction with the heatsink mounted on top without requiring the deployment of a liquid cooling system. In some versions of the system, two internal fans are deployed so that one cools the motor section while the other cools the power electronics mounted on top.

Although a power figure for the motor was not shared, we can deduce that is less than 12 kw (16 horsepower) based on the description on the Magneti Marelli page (which states that MM motors above 12 kw use water cooling, while all of the air-cooled motors are rated for less than that). This also means the motor on the V6 version is likely more powerful, as it does employ a liquid cooling system.

I expect the V6 version will see a larger benefit while the V8 version will be easier and cheaper to maintain down the road. Both version should offer some improvement and we look forward to seeing the official ratings soon.

[Images: Bozi Tatarevic/TTAC, U.S. Patent and Trademark Office]

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  • Ricky Spanish Ricky Spanish on Jan 16, 2018

    So its a super-duper alternator?

  • Harryc Harryc on Jan 16, 2018

    Okay, I'm not getting something. Let me try to break this down. - This thing sits in the front of the engine - The engine drives it via the serpentine belt - At cruise or on overrun, it draws power to a 48V battery pack and also acts as an alternator. - On acceleration (especially from a stop), it supplies torque to the SERPENTINE BELT and thus to the crank shaft, spinning the engine and thus the transmission. - It also spins the engine for start/stop operation. Am I missing something? This seems like a huge step backward from the systems that sit between the engine and transmission, though I guess getting an alternator and 48V electrical system out of it is somewhat elegant (?)

    • See 4 previous
    • El scotto El scotto on Jan 16, 2018

      @Master Baiter Magneti Marelli is in orbit int the FIAT solar system, not exactly a subcontractor. For now.

  • BklynPete So let's get this straight: Ford hyped up the Bronco for 3 years, yet couldn't launch it to match the crazy initial demand. They released it with numerous QC issues, made hay for its greedy dealers, and burned customers in the process. After all that, they lose money on warranties. The vehicles turn out to be a worse ownership experience than the Jeep Wrangler, which hasn't been a paragon of reliability for 50 years. The same was true of the Aviator, Explorer, several F-150 variants, and other recent product launches. The Maverick is the only thing they got right. Yet this company that's been at it for 120 years. Just Brilliant. Jim Farley's non-PR speak: "You don't get to call me an idiot. I get to call myself an idiot first."Farley truly seems hapless, like the characters his late cousin played. Bill Ford is a nice guy but more than a bit slow on the uptake too. They have not had anything resembling a quality CEO since Alan Mulally turned the keys over to Mark Fields - the mulleted glamor boy who got canned after 3 years when the PowerShi(f)t transaxles exploded. He more recently helped run Hertz into the ground with bad QC and a faulty database that had them arresting customers. Ford is starting to resemble Chrysler in the mid-Seventies Sales Bank era. Well, at least VW has cash and envies Ford's distribution reach and potential profitability.
  • Mike Beranek This guy called and wants his business model back.
  • SCE to AUX The solid state battery is vaporware.As for software-limited pack capacity: Batteries are obviously the most expensive component of an EV, so on the rare occasion that pack capacity is dramatically limited (as in your 6-year-old example), it's because economies of scale briefly made sense at the time.Mfrs are not in the habit of overbuilding pack capacity just for fun, and then charging the customer less.Since then, pack capacities have been slightly increased via software because the mfr decides they can sacrifice a little bit of the normal safety/wear margin in the interest of range. We're talking single-digit percentages, not the 60/75 kWh jump in your example.Every pack has maybe 10% margin built into it, so eating into that today (via range increases) means it's not available to make up for battery degradation tomorrow. My 4-year-old EV still has its original range(s) and 100% SOH, but that's surely because it is slowly consuming the margin built into the pack.@Matt Posky: Not everything is a conspiracy to get your credit card account, and the lengthy editorial about this has nothing to do with solid state batteries.
  • JLGOLDEN In order for this total newcomer to grab and hold attention in the US market, the products MUST be an exceptional value. Not many people will pay name-brand money for the pretty mystery. I can appreciate the ambition of selling $50K+ crossovers, but I think they will go farther with their $30K-$40K offerings.
  • Dukeisduke They're where Tesla was when it started - a complete unknown. I haven't heard anything about a dealer network. How are they going to sell these? Direct like Tesla? Franchises picked up by existing new car dealers?