THE BIG STORY 48V - WardsAutowardsauto.com/site-files/wardsauto.com/files/uploads/2016/12/Wards... · By 2025, 18% of the ... come to market this year. “The 48V (mild-hybrid)

THE BIG STORY / MARCH 2016

48V Industry’s Next Power Play

A WHOLESALE CHANGEOVER OF LIGHT-VEHICLE ELECTRICAL SYSTEMS WOULD AFFECT EVERY PART THAT DRAWS A SPARK AND COST BILLIONS OF DOLLARS. BUT THE SHIFT ALREADY IS AFOOT IN THE INDUSTRY. — By James M. Amend

2 / WARDSAUTO / MARCH 2016

Meeting government regulations

Automotive electrical sys-tems taxed by technolo-gies for meeting tighten-ing global fuel-economy and carbon-dioxide

emissions regulations soon will be clamoring for more power, and the answer appears to be shifting from traditional 12V technology to 48V systems capable of handling the higher loads.

A wholesale changeover of light-vehicle electrical systems would affect every part that draws a spark, from ignition and pumping systems to climate con-trols and the motors that operate power seats and sunroofs. In particular, the tiny-but-expensive embedded software controls and chips that give today’s cars and trucks their seemingly boundless intellect would have to be re-engi-neered for a higher voltage level. Costs will run into the billions of dollars.

But the industry historically has embraced such sweeping chang-es, perhaps most notably in cases such as the addition of seatbelts, airbags, stability controls and the downsized-boosted engines now prevalent in global markets and helping automakers meet near-term efficiency standards. Not to be overlooked, either, is the fact the industry conducted a similar changeover 60 years ago in the move from 6V to 12V.

Key regulatory drivers are in

MEETING GOVERNMENT REGULATIONS ..... 2LAUNCHING INTO THE MARKETPLACE ..... 4

WHY FLIP THE SWITCH? ..... 6A GLOBAL ROLLOUT ..... 7

SUPPLIERS RAMP UP 48V TECH ..... 8A MIXED OUTLOOK ... 10

DOWNSIDE OF SUPERSIZED VOLTAGE ... 11

48V Industry’s Next Power Play

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place to compel the industry to make the switch, but whether the economics will make sense for individual automakers is unclear, illustrated by a lopsided cost/benefit ratio that doomed a move-ment a decade ago to 42V.

However, WardsAuto interviews with industry executives and a survey of powertrain engineers suggest the transition will occur gradually through the application

of advanced stop-start systems backed by 48V technology rather than a rapid, fleetwide change-over.

“As the electrification of the vehicle expands for fuel economy, (carbon-dioxide emissions) and performance benefits, higher-volt-age systems such as 48V will pro-vide efficiency and performance improvements,” GM product development chief Mark Reuss

tells WardsAuto. Kregg Wiggins, senior vice

president-powertrain division at global parts-maker Continental, says OEMs are gearing up for 48V because, depending on the vehi-cle application, its technologies can provide an efficiency boost of between 5% and 15%.

“There is a very good appetite for 48V in the industry right now,” he says.

GM’s Reuss sees upside, downside to 48V.


Launching into the marketplace

Five OEMs will launch products with Continental’s 48V mild-hybrid stop/start technology in the next two years. The first will happen this year. Launches will occur in North America, Europe and Asia, Wiggins says. By 2025, 18% of the North American fleet alone will utilize some sort of fuel-saving 48V technology, the supplier forecasts.

“We see a very significant pene-tration increase over the next sev-eral years,” Wiggins says.

FCA US powertrain boss Bob Lee calls possibilities of the higher voltage level “intriguing.”

The Italian-American automaker promised in 2014 a “broad pene-tration” of mild-hybrid systems in the U.S. based on a 48V architec-ture beginning this year, although it appears to have tempered its enthusiasm more recently by say-ing it cannot be specific about the timing of future products.

Beleaguered German auto-maker Volkswagen will pursue 48V-backed power as it accelerates into the mild-hybrid segment as part of reboot of its powertrain strategy after its global die-sel-emissions scandal. The high- performance variant of the Audi Q7 with an electrically boosted turbo-charger backed by 48V power will come to market this year.

“The 48V (mild-hybrid) system

uses less-expensive components, yet is fuel efficient and enables additional comfort features, as well

Heyn sees 4 million new vehicles worldwide with Bosch 48V system in 2020.

48-Volt Eco Drive – System Overview

Continental’s belt-alternator 48V system.


as dynamic acceleration thanks to an electronic boost function,” says Markus Heyn, a member of the board of management at supplier giant Robert Bosch.

“The entry-level 48V hybrid is expected to be a new attractive option for drivers in Europe, North America and Asia, and Bosch expects some 4 million new vehi-cles worldwide to be equipped with (our) system in 2020,” he says.

The WardsAuto survey confirms the bullish outlook of industry executives, but also offers a glimpse into other elements of the industry’s global 48V rollout. Among them:n By 2025 in the U.S., 48V tech-

nologies will be present but at levels likely less than 10%.

n Germany-based OEMs will lead with the technology, followed by automakers based in the U.S., Japan and Korea.

n On a regional basis Europe will see volume penetration of 48V technology first, followed by North America and China.

n After powertrain, vehicle sys-tems and components shifting to 48V power will be led by HVAC. Steering, pumping, drive-line, lighting and infotainment will follow.

n The development of common global standards for the imple-mentation of 48V technologies slightly outweighs cost as the greatest hurdle in its rollout.

n Increased electrical content will drive automakers to adopt 48V technologies as much as tight-ening fuel-economy and emis-sions regulations.


Why flip the switch?

Compared with today’s 12V electrical systems, a 48V platform would give automakers the abil-ity to satisfy most future power demands of a vehicle.

Some industry veterans may recall the migration to 12V from 6V begun in 1955, when high-horse-power engines and compression ratios required more cranking power at ignition. The same demands are happening today.

For example, the old 6V archi-tectures used a single engine-con-trol unit to manage functions such as the ignition system. But today’s 12V systems must satisfy the real-time demands of at least 100 ECUs responsible for functions such as fuel injection, lubrication, cooling and throttle control.

Look beyond the engine to the power needs of safety systems, emerging active chassis dynamics and comfort-and-convenience items and the number of con-trollers expands, with each one requiring an incremental demand in power.

A 48V architecture easily would satisfy those needs, as well as those of the future, without eclipsing the 60V threshold considered the tip-ping point into high-voltage territo-ry. High voltage brings with it high cost and introduces safety risks for vehicle service and emergency per-sonnel.

The wiring harnesses of 48V elec-trical systems also are a third the weight of 12V. A high voltage level means a lower current, so wiring

systems can be thinner and lighter. That is critical at a time when auto-makers are looking to trim every gram they can from their cars and trucks to meet fuel-economy and emissions standards.

“Cable harnesses for vehicles contain lots of copper, which can be reduced by going to the higher voltage,” one industry expert com-ments in the WardsAuto survey. “Coupled with remote power con-trollers, it will eliminate the need to send all wires into the passen-ger compartment where all the switches are located.”

A 48V architecture additionally would give vehicle electrical sys-tems greater stability and reduce fluctuations in vehicle voltage levels due to external conditions such as ambient temperature, experts say.

But if 12V has worked so well for so many years, why flip the switch to a higher voltage? Up to now, 12V systems have handled all the extra electrical demands for effi-ciency improvements and, in the near term at least, probably will continue to, a recent report from

the Union of Concerned Scientists suggests.

The UCS says 10% of conven-tional gasoline- and diesel-pow-ered LVs, or 100 of ’15 model-year product variants, in the U.S. met the 2020 CAFE standard of roughly 42 mpg (5.6 L/100 km).

And they are not just hybrids and electric vehicles. Top-selling models meeting the standard included the Ford F-150, Ram 1500 and Honda CR-V.

“Automakers are meeting the challenge of making cleaner cars,” says David Cooke, vehicles analyst at UCS.

Tougher rules are on the way, however. The U.S. industry, for example, faces a fleet fuel-econo-my average of about 54.5 mpg (4.3 L/100 km) by 2025, and experts say a midterm review of the law next year amid record-low pump prices will not result in revisions to loosen the rule.

Therese Langer, program director-American Council for an Energy-Efficient Economy, a group that works closely with the U.S. EPA and NHTSA on fuel-effi-ciency and emissions rulemaking, expects the 54.5-mpg rule to remain on the books whatever may occur at the pump.

“We’re not expecting low fuel prices to be in place for the next 10 years,” she tells WardsAuto at an industry conference in Ann Arbor, MI. “And one of the main reasons for the tougher CAFE rules at this time is to encourage progress on alternative technol-ogy through this low-gas-price period.”

Schaeffler 48V unit for manual transmis-sions.


A global rollout

In Europe and China, efficien-cy standards are getting equally tougher.

Carlos Ghosn, head of the Renault-Nissan Alliance and 2015 president of the ACEA, the European auto manufacturers’ group, expects European Union regulators to soon address CO2 emissions standards beyond 95 g/km by 2020. China likely will follow in lockstep with the EU.

Automakers also have picked much of the low-hanging fruit on the road to greater efficiency.

Technologies such as variable cam-phasing, cylinder deactiva-tion, gasoline direct injection and downsized turbocharged engines already proliferate OEM product portfolios worldwide. So outside of putting a plug on a vehicle, the only way for automakers to meet future fuel-economy and emissions requirements would be switching to a 48V architecture or utilizing it in combination with existing 12V platforms.

A combination approach using pocket-sized 48V-powered drive units replacing conventional alternators, or fixed inside a trans-mission, can electrically boost the performance of mild-hybrid vehicles so buyers will not have to

sacrifice driving enjoyment to save fuel and trim emissions.

“They are actually quite fun to drive,” Jeff Owens, chief tech-nology officer at Delphi, says of 48V technology. “The electric motor provides a boost when pulling away from a traffic light to improve performance in a down-sized engine.”

However, tightening global regulatory regimes is not the overwhelming motivation behind 48V technologies. According to the WardsAuto survey, 49.6% of respondents consider increased electrical content as the main driver, compared with 50.4% seeing regulations as the leading catalyst.

Electric turbocharger of Audi SQ7 V-8 uses 48V technology.

Audi SQ7 TDI


Suppliers ramp up 48V tech

Global suppliers such as Continental, Delphi, Bosch, Remy, Schaeffler and Johnson Controls are poised to take advantage of the 48V migration.

In its simplest iteration, a 48V system backed by a rechargeable lithium-ion battery would in the near term replace a conventional alternator and power accessories traditionally run by the inter-nal-combustion engine. Taking those tasks off the shoulders of the engine would save energy and result in better fuel economy and fewer emissions.

Key parts migrating to a 48V power supply include turbocharg-ers and superchargers, beginning with the Audi SQ7 TDI hitting the streets of Europe in the spring.

The Audi large CUV uses a 48V system to power an electric tur-bocharger. Energy for the unit is stored in a Li-ion battery and recouped during braking. The bat-tery is mounted beneath the lug-gage compartment and contains 0.47 kWh of energy with an output of 13kW. A DC/DC converter mates the 48V power to the car’s broader 12V system, the latter using a tra-ditional lead-acid battery.

Originally showcased in the Audi RS5 concept car, the 48V subsys-tem requires a new generator, which operates with an efficiency level of more than 80% at an out-put of up to 3 kW.

Altogether, the 4.0L V-8 in the

SQ7 boasts 429 hp and 663 lb.-ft. of torque to take the truck from 0-62 mph (100 km/h) in 4.8 sec-onds. Combined consumption in the European test cycle is 31.8 mpg (7.4 L/100 km) and CO2 emis-sions limited to 194 g/km.

Audi considers the technology a milestone in its electrification strategy, which will include 25% of its U.S. sales by 2025. The 48V-backed V-8 also forms the basis for smaller V-6 engine with a similar induction system.

But a 48V unit also could run a vehicle’s air-conditioning system, a major power thief to energy efficiency, or electrically heat the catalyst of an emissions system to reduce pollution at start-up, a major conundrum for industry engineers.

Coolant pumps, water pumps and oil pumps also could switch over to electricity drawn from 48V technology, and the units serve as the backbone for active chassis systems in sports cars and larger

Bosch 48V system used for automated parking.


vehicles seeking aerodynamic gains through lower ride heights at high speed.

The all-new ’17 Bentley Bentayga CUV uses 48V technol-ogy to operate an electrically actuated suspension system that provides on-road ride sophistica-tion and off-road ruggedness. It responds more quickly than a con-ventional hydraulic setup.

The SQ7 also will use 48V tech-nology for its adjustable suspen-sion.

Other advanced 48V units can work in tandem with a vehicle’s transmission during acceleration to reduce the engine’s workload, or to power electric motors in the drive-line to help spin the wheels or pro-vide on-demand all-wheel drive.

Continental offers its 48V Eco Drive system as a cost-effi-cient mild-hybrid solution. The plug-and-play system features advanced stop/start as well as 16 kW (21 hp) of peak power and 38 lb.-ft. (51 Nm) of torque to permit coasting and sailing, where the engine shuts off in low-load condi-tions and the vehicle is propelled electrically. A Li-ion battery pow-ers the system and it recaptures energy during braking to maintain a charge.

“Coasting provides a lot of the fuel-economy benefits,” Wiggins says.

A traditional 12V electrical sys-tem backed by a common lead-ac-id battery would handle all other electrical demands.

Schaeffler offers a 48V module for vehicles with manual trans-missions. The disc-shaped unit is

installed between the engine and the transmission without modifi-cations to the gearbox or the need for additional cooling. Clutches in the unit decouple the engine from the transmission to drive the vehi-cle electrically.

An advanced take on 48V tech-nology serves as the backbone for a Schaeffler concept. Based on a Ford C-Max CUV, the concept would meet 2025 CAFE require-ments. It uses a transmission-driv-en accessory drive that functions as a parallel-hybrid system incor-porating a selectable power flow between the transmission and the 48V MGU-equipped accessory chain. It eliminates the conven-tional belt drive and allows oper-ation of accessories and energy recovery independent from the

ICE. The accessory drive system significantly reduces CO2 emis-sions, Schaeffler says.

Schaeffler also is employing 48V technology on an Audi TT concept car, where an electrified rear axle complements the front-wheel-drive engine. An additional belt-driven starter-generator is connected to the engine and also operates at 48V. A traditional 12V system powers all other electron-ics in the concept car.

Bosch will put a 48V-backed hybrid system into production in 2017 that promises a 15% boost in efficiency and an additional 110 lb.-ft. (150 Nm) of torque to punch up performance. A combination motor-generator and rechargeable Li-ion battery supports the engine with up to 10 kW of electric power.

Bentley Bentayga active suspension system backed by 48V technology.


A mixed outlook

Looking further down the road, Continental sees potential for mating a 48V-backed mild-hybrid system with connected-vehicle technology to gain even more efficiency. If a vehicle can com-municate with the transportation infrastructure, as Continental has demonstrated with its e-Horizon navigation technology, it could know when to engage coasting for an upcoming traffic light or provide electrical boost for an upcoming incline in the roadway.

“It will know the most efficient way to drive the vehicle accord-ing to the route you are taking,” Wiggins says.

The Japanese appear lukewarm toward 48V technology, perhaps because they are far more invest-ed in full hybrids at this point.

A senior engineer at Denso tells WardsAuto it is a “halfway” mea-sure to improving fuel economy.

“Of course, we’ll work with our OEM partners if there’s interest,” he adds. “But so far we haven’t had much demand.”

A senior engineer at Mitsubishi Electric confirms the supplier is working on the technology, but wants clearer direction from OEMs before pursuing it more aggres-sively.

“We’re aware that European car makers are interested in the tech-nology,” he says. “We’re aware that the technology can improve fuel efficiency. But we (currently) have no business. Perhaps in five years’ time.”

Results from the WardsAuto survey underscore the conserva-tive sentiment expressed by the Denso and Mitsubishi engineers, as 61.7% of respondents see German OEMs leading the roll-out. U.S.-based automakers are seen at No.2 (45.1%), followed by Japan (37.9%), Korea (11.7%) and China (9.1%). Europe will be the lead market in terms of volume

penetration of the technologies, according to 54.1% of survey-tak-ers, trailed by North America (31.2%) and Asia (14.7%).

“Use in Europe is likely first,” one respondent offers. “However, the European vehicle OEMs could introduce 48V to North America, thus kick-starting the market. The question is how much 48V is really needed in high-volume models.”

Continental’s Wiggins expects 18% of North American fleet with 48V by 2025.


Downside of supersized voltage

History suggests there is reason for reservations over 48V technol-ogy, whether as a complement to 12V systems or as a complete overhaul of the vehicle’s electrical architecture.

In the 1990s, the industry was on the verge of shifting to a 42V architecture. In fact, Daimler was so bullish about the prospect of a 42V system to meet the growing power demands of its Mercedes-Benz luxury vehicles it created a “42V” sub-brand.

But motor technology, such as those driving the emerging elec-tric power-steering systems of the day, became so efficient that pre-vailing 12V systems could handle the work. The 12V systems them-selves become more capable, and for hybrid applications many automakers simply moved to a high-voltage network with safety measures.

“The industry needed a level of hybridization beyond what 42V could provide,” says Daryl Wilson, vehicle performance engineer for the redesigned ’16 Chevrolet Malibu Hybrid sedan. “We eventu-ally made a bigger jump.”

Wilson worked on GM’s belt-al-ternator-starter hybrid technol-ogy of the previous decade. The Saturn Vue, Chevy Equinox and Malibu hybrids used a 42V system with a nickel-metal-hydride bat-tery in tandem with a 12V electri-cal system.

The mild-hybrid system proved too costly for buyers. “A big part was the on-cost,” Wilson tells WardsAuto.

When GM took another run at hybridization with its e-Assist powertrain for the Malibu and Buick LaCrosse and Regal, it jumped to a 115V system with a Li-ion battery. However, the fuel-economy improvement of eAssist was unspectacular, so with the ’16 Malibu Hybrid the auto-maker uses a high-voltage 300V unit based on the Chevy Volt EV.

The latest Malibu’s new hybrid system aids in acceleration and runs the car’s air-conditioning unit to help deliver 48 mpg (4.9 L/100 km) in the city cycle.

So some industry executives are skeptical 48V technology will be a long-term solution to a vehicle’s power needs and, as GM did with the Malibu hybrid, a more cost-ef-ficient route might be skipping straight to a high-voltage network.

Others, meanwhile, see 48V technology as a temporary bridge

to full electrification via batteries or hydrogen fuel-cell vehicles.

GM’s Reuss sees 12V remaining the dominant electrical architec-ture for years to come. He thinks 48V technology will be rolled out only where a continuous high-er voltage would be necessary. Otherwise, 48V systems would require added safety precautions such as special fuses, breakers and disconnects.

Reuss also cites a litany of embedded controls that require a single-digit voltage, as well as the cost of switching over hardware and software to 48V from 12V. And while the lower current of 48V may result in smaller wiring cables the weight-saving could be offset by the addition of Li-ion batteries and generators that 48V technolo-gies employ.

“The greatest hurdle is the cost-to-benefit associated with 48V systems,” Reuss says. “In addition to the cost of the com-ponents, there has to be enough CO2 (reduction), fuel economy and

JCI among key Li-ion battery suppliers for 48V systems.


performance benefits associated with these systems that will sway the cost-to-benefit ratio favorably for the customer.

“At 48 volts, the power electron-ics and energy-storage system (batteries) currently cost more than the very mature 12V com-ponents used on virtually all cars today,” he says.

Wiggins says the application of 48V technology differs among automakers and their particular powertrain strategy.

“There are different tradeoffs,” he admits. “You can look at (48V) as one alternative.

“But if you already have a capac-itized engine that you’re produc-ing for your vehicle, then (48V) is a relatively straight forward way to add fuel economy to an existing powertrain. If you’re doing anoth-er powertrain update and you choose a different fuel-economy measure, then it may provide dif-ferent benefits. There is a broad range of options, and this is one effective way.”

Among the key enablers of 48V technologies, says Craig Rigby, strategist-advanced market and technology at Johnson Controls, are recent advances in Li-ion bat-teries and falling cell costs. When the push was on to move to 42V, lead-acid batteries dominated the market. While excellent for storing energy and providing a good jolt at startup, they are poor perform-ers on the recharging front.

“Lead-acid batteries have a weakness around that charge power,” he says.

But Li-ion batteries excel in that

area, making them natural mates for regenerative braking.

And moving just a handful of power users to 48V would make the transition less costly.

“If you can think of the cascade effect on all components being redesigned and requalified, the related investment would be very, very significant,” he says.

However, cost may not be the greatest hurdle to 48V technolo-gies. According to the WardsAuto survey, 35.9% of respondents con-sider the development of common global standards the biggest stick-ing point, followed by cost (31.9%), volume uncertainty (11.5%), polit-ical uncertainty (6.3%) and engi-neering capacity (5.9%).

Whatever the pace of the roll-out, or wherever it originates, 48V technology likely will feature

prominently in global powertrain playbooks over the next 10 years.

“(48V) is becoming an extremely attractive lever we think (OEMs) will be pulling around the world,” Delphi’s Owens says. “It will be a lever we think will be pulled very, very hard.” WA

James M. Amend is a senior editor for WardsAuto. He has covered product, technology and business news in the automobile industry for nearly two decades and is based in Southfield, MI.

Source: WardsAuto

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THE BIG STORY 48V - WardsAutowardsauto.com/site-files/wardsauto.com/files/uploads/2016/12/Wards... · By 2025, 18% of the ... come to market this year. “The 48V (mild-hybrid)