New models and designs are constantly being released in the automotive industry, and electrified models are no exception. As the stable expands from almost exclusively compact cars with a modest driving range to larger categories like trucks and SUVs intended for jack-of-all-trades use, the industry has begun to introduce new technologies to expand range.
Key Takeaways
- Extended range EVs (EREVs) combine a primary electric drivetrain with a small range-extending combustion engine or generator, offering BEV-style driving with ICE backup range.
- EREVs require shops to service both high-voltage battery systems and traditional combustion components — expanding the diagnostic footprint.
- Models like the Chevy Volt (discontinued), BMW i3 Rex, and newer Chinese EREVs show the technology’s diversity and growing global market.
- Battery diagnostic tools must cover both the large traction pack and the 12V auxiliary system across EREV platforms.
Some of these new models slot into a category called Extended Range Electric Vehicles, or EREVs, but they might not be exactly what you think they are. Here’s what you should know about EREVs and how they could impact automotive service.
What Makes an EREV?
With a name that includes ‘extended range’, you might expect that an EREV is an electric vehicle with a larger battery capacity than average, giving it more stored energy to give you more driving range. But that’s not the case.
In fact, the battery is typically a little smaller than your average EV. That’s because the increased miles you can drive are due to an onboard fossil-fueled generator that kicks in when the battery is depleted. With a gas-powered engine as a generator on board, the vehicle can operate with a smaller battery pack and simply recharge itself as necessary, adding more miles without having to stop and plug in.
Yet, the propulsion system is exclusively powered by battery power. The drivetrain does not include axle shafts or propeller shafts nor a transmission connected to the gas motor. It’s exclusively used for battery charging, and the combustion engine only runs when the battery power drops to a certain threshold.
Are Extended Range EVs Just Hybrids?
Interestingly enough, the comparison between EREVs and hybrid models shoes a large difference between the technologies. Unlike EREVs, hybrid models almost always have the combustion engine parallel with the EV system, meaning that the vehicle can be propelled by either electric or combustion power. With extended range EVs, the generator is in series, so it exclusively charges the battery pack.
As well, most hybrid vehicles are more dependent on the gas engine than the battery power it can store. Their battery packs tend to be quite small, often under 20 kWh, with all-electric ranges of 30 to 50 miles. The combined range is much higher with the support of the gas engine, often getting 400 to 600 miles between electric and ICE power.
For an EREV, though, the battery pack contains much more energy for an electric-only range. One recently announced model has a 92-kWh battery pack that can provide more than 140 miles of all-electric range. But rather than having to stop and plug in, the generator powers it for an additional 550 miles of range.
Plus, another differentiator is in performance. Hybrids tend to be relatively tame in terms of their acceleration, not exceeding the gas-powered performance. EREVs have the benefit of incredible torque and power from electric motors with no lag, far exceeding the gas-only comparable vehicle in terms of the rated horsepower, torque, and 0-60 acceleration figures.
At first glance, they might seem similar, but there are stark differences between the two.
Where EREVs Slot Into the Marketplace
Despite several years of progress, range anxiety remains a major factor for anyone considering the switch to a BEV. What happens if the charge runs out where they’re nowhere near a charging station, or what if they encounter an out-of-order station – as has been one of the growing pains? This is one of the primary focuses: attracting consumers who are hesitant based on the emerging tech pain points. With EREVs, consumers are more comfortable knowing they can travel longer distances without frequent charging stops.
Plus, they’re an excellent compromise where sustainability is concerned. Resources for EV batteries are finite, and the blend of both battery and ICE power offers an eco-friendly solution – even more so than traditional hybrids. Not to mention, the servicing requirements for EREVs are closer to that of an EV than an ICE vehicle, albeit with light engine maintenance requirements.
However, there’s question about how large a segment there will be that find EREVs right for their needs. What’s unclear is the financial balance – how affordable are extended range EVs compared to BEVs, hybrids, and ICE-only models? Will they hold their resale value better than the quickly depreciating EVs? And will the efficiency of an EREV pay off in the long run compared to other styles? These questions will need to be answered as the technology becomes more mainstream.o
How EREVs Affect Automotive Service Businesses
Service shops, both franchised dealerships and independent facilities, have been incorporating EV technology into their service offerings as the demand increases. As EREVs enter the market more prominently, they introduce new opportunities and challenges for these shops.
Service Needs are Changed Yet Again
With fewer moving parts than traditional ICE vehicles, EREVs reduce the need for regular maintenance like transmission work and some fluid changes. However, because they have a gas engine for backup range, there’s still some maintenance to consider like oil changes and tune-ups, so there’s a level between EV and ICE in terms of requirements. Areas shops will need to focus will include battery diagnostics and software updates like there are in EVs, and mechanical service for the generator.
Technicians Need to be Up to Date
Like the introduction to EVs, dealerships will need to have technicians who are familiar with the ICE-EV integration and the advanced diagnostic equipment needed to service it. There’s an investment needed in terms of tools as well as education.
Aftermarket Opportunities
There’s also a growing market for aftermarket products tailored to EREVs, from charging accessories to range-extending software updates. Dealerships can position themselves as the go-to resource for these products and build customer loyalty.
What to Make of EREVs
Technology is changing as the search for more fuel efficient, lower emission vehicles continues. EREVs appear to have a niche carved out, especially as it curbs range anxiety and reduces the strain on acquiring materials for battery packs. There will be an impact on service shops as these models hit the market, but the extent of that impact is still unknown.
What we do know is that battery health will continue to be a major influence in keeping these models powered throughout their lifespans, and shops need to be trained and equipped to handle them with diagnostic and testing service equipment.
Frequently Asked Questions
What is an extended range EV?
An extended range EV (EREV) is a plug-in electric vehicle that uses an electric motor as its primary drive but includes a small internal combustion engine (or generator) that activates when the battery is depleted — extending range beyond what the battery alone provides. The combustion engine never directly drives the wheels; it only generates electricity. The Chevy Volt was the best-known US example.
How is an EREV different from a hybrid?
In a traditional hybrid, the combustion engine can directly drive the wheels. In an EREV, the combustion engine is a generator only — electricity is always the propulsion source. This gives EREVs EV-like efficiency and driving feel when the battery has charge, unlike most hybrids.
Why are EREVs gaining renewed interest?
Range anxiety remains a barrier to full BEV adoption, particularly in markets with limited charging infrastructure. EREVs address this directly — drivers get near-EV efficiency for daily driving but can refuel with gasoline for longer trips. Chinese automakers in particular have invested heavily in EREV platforms.
What service challenges do EREVs present?
EREVs combine high-voltage battery systems with combustion engine components — shops need technicians certified in both. Battery health diagnostics, cooling system service, HV safety procedures, and traditional engine maintenance all apply. The range extender engine typically runs at fixed RPMs to generate power efficiently, so its maintenance pattern differs from a conventional engine.
How long do EREV batteries last?
EREV traction batteries are typically smaller than full BEV packs (since they don’t need to provide all range), which often means they cycle more frequently if the range extender isn’t used. Battery longevity depends heavily on how the driver uses the vehicle — primarily electric (good for the battery) or primarily ICE (potentially more cycles).
Do shops need special tools to service EREVs?
Yes. High-voltage safety equipment and procedures are mandatory for EREV battery work. EV-compatible battery diagnostic tools are needed for the traction pack, while standard tools cover the range-extender engine. Shops that have already invested in HV safety training for PHEVs and BEVs are well positioned to service EREVs.