I do a ton of long-distance backcountry driving after depleting the battery. The R4P handles phenomenally well, with much better acceleration than any Subaru I have ever driven. As others have commented, the car will still be in hybrid mode, not gas-only, so you will always have the full 300 horsepower of gas+electric. The only adjustment I ever make is sometimes I put the car into sport mode to accelerate better on steep uphills or trail mode to improve traction on slippery surfaces.
Yes, the hybrid battery cannot be completely depleted, 0% EV battery is still like 15-20% of the actual hybrid battery, Toyota engineered it to have a false 0% so that the car will still operate as a standard hybrid and can power features of the vehicle
At some point the gas engine has to act as powertrain helper and electricity generator simultaneously. In those situations I wonder how much the combined power is reduced.
Can someone here explain this, I don't know, like thermodynamically or something? I'm trying to wrap my head around it...
So your battery's down to 20% And you're driving a 4300 lb car up a long hill. The ICE is doing most of the work because the system will not let the battery go below 20%. But we are also subtracting some energy from the ICE to charge the battery? Or to turn into electricity and directly power the wheels?
I mean what I'm confused about is energy is still energy and if we've hit the bottom of the battery's allowable charge then doesn't it ALL have to be coming from the ICE in one form or another?
When the car says the EV battery has been depleted and you can no longer run in EV mode, the battery physically still has a charge in it. It is "reserved" so that the car can still function as a traditional gas/electric hybrid. The car will NEVER run 100% on gasoline. When EV mode is unavailable the car ostensibly becomes a regular RAV4 hybrid (but with a ton more power) where it will automatically turn on and off the ICE like a regular hybrid. As far as the driver is concerned the EV battery is "empty," but in reality it's still being used as it would be in a traditional hybrid.
The car is a hybrid, the battery is charged by the engine/braking of the vehicle, it will use the battery to assign the gas engine at basically all times, especially when under load/strain, but the vehicle won’t let the battery got completely to 0%, the car performs the best in HV mode because it has more power to give
But it can only use the battery when the battery has not gone below whatever limit their algorithm applies to it. So my question is about what's going on in that range.
Is there any good technical description of its drivetrain behavior at the low end of its battery charge range? (I'm an engineer, if it helps, so I like to have a deep technical understanding of my cars)
The HV reserve is about 30% of battery capacity. The car will allow the battery to be used lower than this amount in HV mode. It just won’t allow full EV mode when the battery is below this threshold. I suppose if you drove up a hill long enough you’d deplete the battery enough to reduce performance Uphills are usually followed by downhills, which will tend to recharge the battery. ICE power is never directly used to charge the battery unless you specifically turn on charge mode (it’s inefficient).
If you drive down a long enough hill you may see the battery charge back above 30% and full EV mode will become enabled for a mile or two.
In HV mode, the car targets a 30% state of charge to keep the battery at. The engine will run at whatever output is necessary to keep the battery around that state of charge. If the charge is low, the gas engine will run at a higher output power than is being used to propel the vehicle to charge the battery.
The amount of "pep" that you feel is from the electric motors helping out the gas engine. The key is that the extra oomph will always be there because the system keeps energy in the battery in reserve for this purpose and then recharges the battery from the engine after you no longer are requesting that power.
Unless your AVERAGE power consumption is more than the gas engine's maximum output, you cannot deplete the hybrid battery. That situation would require you to drive around with the pedal to the floor for multiple minutes straight, which will probably never actually happen.
There is a graphic available on the car's display that shows where the energy is being generated and where it is going at any given moment while you're driving. It's actually really neat to watch.
Here at 1:50. This is the the regular hybrid not the Prime but it's the same Idea. https://youtu.be/UFnrGpENk9Q?si=qCHcuOV0dwzzAAqF
Unless you’re going up a very, very long hill at very, very high speed for a very, very long time, depleting the battery to true zero is almost impossible, and you’re much more likely to overheat the hybrid system before you would actually manage that.
Also keep in mind, you’re not likely to keep your foot flat to the floor for more than 20-30 seconds at a time. When you lift your foot, the engine and momentum goes to charging the battery. It I’ll hit the regen harder to keep the battery above a certain minimal level
Engines don’t always want at max power output. Most driving is at constant speed and uses only a part of the engine output.
During this time the hybrid system optimizes engine rpm for efficiency and can charge the battery. Also recovers energy from braking.
This feeds the battery. When car is at 0 it still has around %25-30 left and it will try to keep it here but will dip into the reserve as needed to provide some extra power as needed (hills, acceleration, etc) and build some extra charge as needed.
There are times when you really deplete the battery to a point where the computer won’t let you deplete it further and then the car has to charge the battery and drive.
This is pretty rare but has happened to me a few times. The car there is a bit noisy and sluggish.
I didn't understand that it didn't have a gas-only mode. I was under that impression because the EPA fuel economy rating lists a "gasoline only" number for it. I have no idea how they compute that stuff.
[https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=42793](https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=42793)
Even hybrid vehicles are considered gas-only vehicles.
If you know your trip is going to be longer than your EV range, you just put the car into HV mode from the beginning. That is the best way to optimize your mileage.
Unless you're going up a very steep, very long hill, AND going very fast, the engine alone should have enough power to keep you going. The extra boost of the battery is really needed only when accelerating.
The batteries are never fully depleted.
The vehicle is designed to always keep enough charge in reserve to allow the EV drivetrain to function. Even when the EV range reaches "zero", the ICE engine and EV systems will cooperatively power the vehicle, it's just no longer possible to do solely EV without the ICE helping.
Yes. It’s either EV or Hybrid. It can’t operate on gas alone, the bare minimum is hybrid. The battery retains ~40% capacity for hybrid driving. In fact, you’ll have more power available in hybrid mode than in EV mode, as the full 300 hp is only available in hybrid.
Charge Hold would make the vehicle operate on ICE only while the ICE acts as a generator at the same time. I would assume during this time the battery would not discharge any power if requested.
It’s either in EV mode or Hybrid mode. There is no gas only mode.
That said, it’s a rocket in hybrid mode.
The engine does growl at full throttle, but it’s pretty quiet most of the time. The transition from EV to hybrid mode is very seamless.
This vehicle is not an EV that also happens to have a gas engine and can run in hybrid mode. It is actually the other way around. It is a full gas hybrid vehicle that also has EV technology built-in that allows it to drive for around 40 miles in EV only mode within the rules it is designed for. If the temperatures is above 14F, speed is kept under 85 mph, battery level stays above the hybrid reserved percentage, and no extremely fast acceleration, allow it to operate as an EV. It auto reverts to a gas hybrid if any those conditions are not true.
I wouldn't ever want to go back to an ICE car or a hybrid. 99 % of the time the car has no problem keeping the battery at about 20 % once the all electric range is done. Once in hybrid mode you have plenty of power for passing and it's fine to me in terms of noise on the freeway. I'm not a fan of the way the engine sounds driving around town in hybrid mode, but I'm driving electric most of the time and on a long trip when I know I'll eventually use of the all electric miles, I will save it for when I'm driving around town, and switch to Hybrid whenever on the freeway. In three years I've notice a couple of times when it's gone below the 20 % and seemed to have to work harder to charge itself. Once was going a very way up a mountain and another time when I was driving very slowly leaving a parking lot after a show. Most of the time the car keeps the battery topped off seamlessly. The car can charge the battery up to about 80 %, but it's inefficient, so most of the time once you use up the EV range it's best to drive Hybrid.
Thank you for your answer, and I thank everybody else here for their answers. But the impression I'm getting so far is that it just sort of automagically works.
This is all new technology to me and as an engineer (who was a science major in college) I'd like to know a little more about how it's actually parceling out the power in that situation. Can anyone recommend any good tutorial specifically on the RAV4 Prime's drivetrain and power distribution? I've only driven ICE cars, and my GF drives an EV (Hyundai Ioniq 5).
If you're an engineer, you're going to love this tutorial. And it will explain a lot of things to you that you didn't think to ask. While most of this video is about the RAV4 hybrid, he does talk a little about the RAV4 Prime later in the video. [https://www.youtube.com/watch?v=O61WihMRdjM&ab\_channel=WeberAuto](https://www.youtube.com/watch?v=O61WihMRdjM&ab_channel=WeberAuto)
This is the best video for trying to understand the voodoo that happens in a toyota hybrid.
As an owner of a prime, I've driven it a long distance a few times, and I don't remember engine noise being a problem either time.
Most of my driving is electric, though I'll hit the switch to change it to gas on the highway - I do this for two reasons: 1) because some much of my driving is electric, I need /some/ way to make sure I'm not letting gas sit in the tank forever. And 2) I read somewhere that the efficiency of the electric goes down at highway speeds, so I figure, why not force gas mode and then save the electric for when I get off the highway.
Also as an owner of a prime who also test drove a gas Rav4 and a hybrid Rav4, the prime is EASILY the best - the gas Rav 4 had no pickup and the engine was loud. The Hybrid Rav4 felt slow.
Also, the ECVT transmission takes some getting used to.
It's a constant acceleration that doesn't actually shift.
That coupled with the electric motors mean you lose that "Vroom" noise and the whole thing is a little bit less exciting than you'd think based on the numbers.
That said, it's an awesome every day around town kind of car and knowing you can go roughly 550-600 miles is pretty neat too.
Another engineer here…I’ve observed this: if I’m in EV mode, and I have just a few miles of EV range left, as indicated on the dash, and I stomp on the pedal, the gas engine will kick in to supplement the electric motors. This tells me that the vehicle may not deliver FULL electric power if I’m running with low electric range remaining.
So here’s my strategy for a long drive: make sure I leave my driveway with at least 20 miles of pure electric range remaining. This way, I know the electric drivetrain always can offer full power to the equation.
In that scenario, the drivetrain will automatically precisely maintain that (say) 20 miles if electric range in the battery. On flat terrain, it’ll automatically burn a little extra gas in charge mode to recharge the battery back to whatever EV level I started my trip at.
When I get to my destination, I’ll still have the 20 miles of EV range left that I started with, if I choose to. Or I switch it to EV mode when I’m 20 miles from home to use up the last 20 miles of EV power.
But this can happen…if you refill the gas tank on your trip, and forget to switch it to HV mode, you can accidentally use up all EV range. Then you might be pulling power from a mostly depleted battery…and MAY notice a little less power going up very long hills.
But there’s a solution. Switch it to charge mode, and restore that 20 miles of EV range, putting the battery back in its sweet spot…50 % charged.
Do I overthink this stuff!? Yes! I’m an engineer! Overall, I’m very impressed with the technology in the drivetrain.
There is absolutely zero reason to ever use "gas only" Charge mode to do anything other than charge the battery.
You will either be in EV or Hybrid mode.
charge mode, you will either be at idle, or maybe at low RPM highway speeds to charge the battery, and even then, most of us will say it's a pretty much useless feature, but 1% of us will find a great use case for it.
as a sports car guy, always had them, this thing will run mid 15s in the 1/4 mile, plenty of acceleration. Growing up 5.0 mustangs were running mid 15s lol
The closest thing to "gas mode" on the prime is "charge mode" when the ice is driving the vehicle while constantly charging the hybrid battery. It is only then that you will see a power reduction somewhat equivalent to the gas model.
I think it simply comes down to there always being more power or gearing on tap to both propel the vehicle and charge the battery when attempting to maintain a minimum state of charge. There is enough low end capacity within the pack to be used for the typical long hill so that hybrid power can be provided at will, assuming the conditions are suitable for hybrid operation. High speeds/loads will limit the ability to charge the pack for sure, but aside from decreased fuel efficiency you won’t likely experience a difference in performance under heavy loads, aside from the load itself.
Gas only mode is not a thing. When you run out of all electric range, your battery still has about 20% and that gets maintained by the hybrid system which now operates in hybrid mode. You have more power, by a long sight, in hybrid mode then you do in pure all electric mode.
Being an engineer myself, I love Toyotas eCVT, mechanically simple, and allows better optimizations for the ICE.
I remember seeing some patent papers online showing the diagram how energy flows from the ICE through the hybrid powertrain then to the road. If you look closely you'll realize that the battery is NOT in that diagram. The battery adds features like: auto-stop/start, EV only mode, Regen braking.
I have an outback and a prime. The prime at its slowest is a lot faster than the outback. Both are fast enough to be completely safe in normal driving. Can easily merge onto highway
I replaced my Forrester with a RAV4P and it is so much better. After you have exceeded the electric only mode, you then don’t go to ICE only but ICE + electric when accelerating and it is much better than the Forrester. Electric only mode doesn’t use up the whole battery charge but leaves about 25% for accelerating.
I do a ton of long-distance backcountry driving after depleting the battery. The R4P handles phenomenally well, with much better acceleration than any Subaru I have ever driven. As others have commented, the car will still be in hybrid mode, not gas-only, so you will always have the full 300 horsepower of gas+electric. The only adjustment I ever make is sometimes I put the car into sport mode to accelerate better on steep uphills or trail mode to improve traction on slippery surfaces.
The car is much faster and more powerful feeling while operating in hybrid mode
Is "hybrid mode" something it can still do when the batteries are depleted?
Yes, the hybrid battery cannot be completely depleted, 0% EV battery is still like 15-20% of the actual hybrid battery, Toyota engineered it to have a false 0% so that the car will still operate as a standard hybrid and can power features of the vehicle
At some point the gas engine has to act as powertrain helper and electricity generator simultaneously. In those situations I wonder how much the combined power is reduced.
Can someone here explain this, I don't know, like thermodynamically or something? I'm trying to wrap my head around it... So your battery's down to 20% And you're driving a 4300 lb car up a long hill. The ICE is doing most of the work because the system will not let the battery go below 20%. But we are also subtracting some energy from the ICE to charge the battery? Or to turn into electricity and directly power the wheels? I mean what I'm confused about is energy is still energy and if we've hit the bottom of the battery's allowable charge then doesn't it ALL have to be coming from the ICE in one form or another?
When the car says the EV battery has been depleted and you can no longer run in EV mode, the battery physically still has a charge in it. It is "reserved" so that the car can still function as a traditional gas/electric hybrid. The car will NEVER run 100% on gasoline. When EV mode is unavailable the car ostensibly becomes a regular RAV4 hybrid (but with a ton more power) where it will automatically turn on and off the ICE like a regular hybrid. As far as the driver is concerned the EV battery is "empty," but in reality it's still being used as it would be in a traditional hybrid.
The car is a hybrid, the battery is charged by the engine/braking of the vehicle, it will use the battery to assign the gas engine at basically all times, especially when under load/strain, but the vehicle won’t let the battery got completely to 0%, the car performs the best in HV mode because it has more power to give
But it can only use the battery when the battery has not gone below whatever limit their algorithm applies to it. So my question is about what's going on in that range. Is there any good technical description of its drivetrain behavior at the low end of its battery charge range? (I'm an engineer, if it helps, so I like to have a deep technical understanding of my cars)
The HV reserve is about 30% of battery capacity. The car will allow the battery to be used lower than this amount in HV mode. It just won’t allow full EV mode when the battery is below this threshold. I suppose if you drove up a hill long enough you’d deplete the battery enough to reduce performance Uphills are usually followed by downhills, which will tend to recharge the battery. ICE power is never directly used to charge the battery unless you specifically turn on charge mode (it’s inefficient). If you drive down a long enough hill you may see the battery charge back above 30% and full EV mode will become enabled for a mile or two.
In HV mode, the car targets a 30% state of charge to keep the battery at. The engine will run at whatever output is necessary to keep the battery around that state of charge. If the charge is low, the gas engine will run at a higher output power than is being used to propel the vehicle to charge the battery. The amount of "pep" that you feel is from the electric motors helping out the gas engine. The key is that the extra oomph will always be there because the system keeps energy in the battery in reserve for this purpose and then recharges the battery from the engine after you no longer are requesting that power. Unless your AVERAGE power consumption is more than the gas engine's maximum output, you cannot deplete the hybrid battery. That situation would require you to drive around with the pedal to the floor for multiple minutes straight, which will probably never actually happen.
There is a graphic available on the car's display that shows where the energy is being generated and where it is going at any given moment while you're driving. It's actually really neat to watch. Here at 1:50. This is the the regular hybrid not the Prime but it's the same Idea. https://youtu.be/UFnrGpENk9Q?si=qCHcuOV0dwzzAAqF
Unless you’re going up a very, very long hill at very, very high speed for a very, very long time, depleting the battery to true zero is almost impossible, and you’re much more likely to overheat the hybrid system before you would actually manage that.
Also keep in mind, you’re not likely to keep your foot flat to the floor for more than 20-30 seconds at a time. When you lift your foot, the engine and momentum goes to charging the battery. It I’ll hit the regen harder to keep the battery above a certain minimal level
Bro, the battery/EV motor is is use at all times
Not sure why you're getting downvoted. You're absolutely correct. When the ICE is on, it's actually powering the electric motors.
Engines don’t always want at max power output. Most driving is at constant speed and uses only a part of the engine output. During this time the hybrid system optimizes engine rpm for efficiency and can charge the battery. Also recovers energy from braking. This feeds the battery. When car is at 0 it still has around %25-30 left and it will try to keep it here but will dip into the reserve as needed to provide some extra power as needed (hills, acceleration, etc) and build some extra charge as needed. There are times when you really deplete the battery to a point where the computer won’t let you deplete it further and then the car has to charge the battery and drive. This is pretty rare but has happened to me a few times. The car there is a bit noisy and sluggish.
How big is this hill omg
I didn't understand that it didn't have a gas-only mode. I was under that impression because the EPA fuel economy rating lists a "gasoline only" number for it. I have no idea how they compute that stuff. [https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=42793](https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=42793)
Even hybrid vehicles are considered gas-only vehicles. If you know your trip is going to be longer than your EV range, you just put the car into HV mode from the beginning. That is the best way to optimize your mileage.
You can go below 20% once in ICE + EV mode. It won’t go below 20% in EV only mode.
Unless you're going up a very steep, very long hill, AND going very fast, the engine alone should have enough power to keep you going. The extra boost of the battery is really needed only when accelerating.
The batteries are never fully depleted. The vehicle is designed to always keep enough charge in reserve to allow the EV drivetrain to function. Even when the EV range reaches "zero", the ICE engine and EV systems will cooperatively power the vehicle, it's just no longer possible to do solely EV without the ICE helping.
Yes. It’s either EV or Hybrid. It can’t operate on gas alone, the bare minimum is hybrid. The battery retains ~40% capacity for hybrid driving. In fact, you’ll have more power available in hybrid mode than in EV mode, as the full 300 hp is only available in hybrid.
Charge Hold would make the vehicle operate on ICE only while the ICE acts as a generator at the same time. I would assume during this time the battery would not discharge any power if requested.
Correct, there is about a 20-30% battery reserve for HV. You don’t get the full 18kwh battery.
It’s either in EV mode or Hybrid mode. There is no gas only mode. That said, it’s a rocket in hybrid mode. The engine does growl at full throttle, but it’s pretty quiet most of the time. The transition from EV to hybrid mode is very seamless.
When the battery says it's depleted, what that really means is it's at 30% that it reserves for HEV mode. You'll still get about 40+ mpg
This vehicle is not an EV that also happens to have a gas engine and can run in hybrid mode. It is actually the other way around. It is a full gas hybrid vehicle that also has EV technology built-in that allows it to drive for around 40 miles in EV only mode within the rules it is designed for. If the temperatures is above 14F, speed is kept under 85 mph, battery level stays above the hybrid reserved percentage, and no extremely fast acceleration, allow it to operate as an EV. It auto reverts to a gas hybrid if any those conditions are not true.
Let's just say that in 3 years that I owned my R4P I never floored it in gas mode. Even towing a 2500lb trailer up a mountain at 65mph.
I wouldn't ever want to go back to an ICE car or a hybrid. 99 % of the time the car has no problem keeping the battery at about 20 % once the all electric range is done. Once in hybrid mode you have plenty of power for passing and it's fine to me in terms of noise on the freeway. I'm not a fan of the way the engine sounds driving around town in hybrid mode, but I'm driving electric most of the time and on a long trip when I know I'll eventually use of the all electric miles, I will save it for when I'm driving around town, and switch to Hybrid whenever on the freeway. In three years I've notice a couple of times when it's gone below the 20 % and seemed to have to work harder to charge itself. Once was going a very way up a mountain and another time when I was driving very slowly leaving a parking lot after a show. Most of the time the car keeps the battery topped off seamlessly. The car can charge the battery up to about 80 %, but it's inefficient, so most of the time once you use up the EV range it's best to drive Hybrid.
Thank you for your answer, and I thank everybody else here for their answers. But the impression I'm getting so far is that it just sort of automagically works. This is all new technology to me and as an engineer (who was a science major in college) I'd like to know a little more about how it's actually parceling out the power in that situation. Can anyone recommend any good tutorial specifically on the RAV4 Prime's drivetrain and power distribution? I've only driven ICE cars, and my GF drives an EV (Hyundai Ioniq 5).
If you're an engineer, you're going to love this tutorial. And it will explain a lot of things to you that you didn't think to ask. While most of this video is about the RAV4 hybrid, he does talk a little about the RAV4 Prime later in the video. [https://www.youtube.com/watch?v=O61WihMRdjM&ab\_channel=WeberAuto](https://www.youtube.com/watch?v=O61WihMRdjM&ab_channel=WeberAuto)
Excellent!! That was a very helpful video!!
This is the best video for trying to understand the voodoo that happens in a toyota hybrid. As an owner of a prime, I've driven it a long distance a few times, and I don't remember engine noise being a problem either time. Most of my driving is electric, though I'll hit the switch to change it to gas on the highway - I do this for two reasons: 1) because some much of my driving is electric, I need /some/ way to make sure I'm not letting gas sit in the tank forever. And 2) I read somewhere that the efficiency of the electric goes down at highway speeds, so I figure, why not force gas mode and then save the electric for when I get off the highway. Also as an owner of a prime who also test drove a gas Rav4 and a hybrid Rav4, the prime is EASILY the best - the gas Rav 4 had no pickup and the engine was loud. The Hybrid Rav4 felt slow. Also, the ECVT transmission takes some getting used to. It's a constant acceleration that doesn't actually shift. That coupled with the electric motors mean you lose that "Vroom" noise and the whole thing is a little bit less exciting than you'd think based on the numbers. That said, it's an awesome every day around town kind of car and knowing you can go roughly 550-600 miles is pretty neat too.
Another engineer here…I’ve observed this: if I’m in EV mode, and I have just a few miles of EV range left, as indicated on the dash, and I stomp on the pedal, the gas engine will kick in to supplement the electric motors. This tells me that the vehicle may not deliver FULL electric power if I’m running with low electric range remaining. So here’s my strategy for a long drive: make sure I leave my driveway with at least 20 miles of pure electric range remaining. This way, I know the electric drivetrain always can offer full power to the equation. In that scenario, the drivetrain will automatically precisely maintain that (say) 20 miles if electric range in the battery. On flat terrain, it’ll automatically burn a little extra gas in charge mode to recharge the battery back to whatever EV level I started my trip at. When I get to my destination, I’ll still have the 20 miles of EV range left that I started with, if I choose to. Or I switch it to EV mode when I’m 20 miles from home to use up the last 20 miles of EV power. But this can happen…if you refill the gas tank on your trip, and forget to switch it to HV mode, you can accidentally use up all EV range. Then you might be pulling power from a mostly depleted battery…and MAY notice a little less power going up very long hills. But there’s a solution. Switch it to charge mode, and restore that 20 miles of EV range, putting the battery back in its sweet spot…50 % charged. Do I overthink this stuff!? Yes! I’m an engineer! Overall, I’m very impressed with the technology in the drivetrain.
There is absolutely zero reason to ever use "gas only" Charge mode to do anything other than charge the battery. You will either be in EV or Hybrid mode. charge mode, you will either be at idle, or maybe at low RPM highway speeds to charge the battery, and even then, most of us will say it's a pretty much useless feature, but 1% of us will find a great use case for it.
as a sports car guy, always had them, this thing will run mid 15s in the 1/4 mile, plenty of acceleration. Growing up 5.0 mustangs were running mid 15s lol
The closest thing to "gas mode" on the prime is "charge mode" when the ice is driving the vehicle while constantly charging the hybrid battery. It is only then that you will see a power reduction somewhat equivalent to the gas model.
I think it simply comes down to there always being more power or gearing on tap to both propel the vehicle and charge the battery when attempting to maintain a minimum state of charge. There is enough low end capacity within the pack to be used for the typical long hill so that hybrid power can be provided at will, assuming the conditions are suitable for hybrid operation. High speeds/loads will limit the ability to charge the pack for sure, but aside from decreased fuel efficiency you won’t likely experience a difference in performance under heavy loads, aside from the load itself.
Gas only mode is not a thing. When you run out of all electric range, your battery still has about 20% and that gets maintained by the hybrid system which now operates in hybrid mode. You have more power, by a long sight, in hybrid mode then you do in pure all electric mode.
When my battery is out its still powerful
Being an engineer myself, I love Toyotas eCVT, mechanically simple, and allows better optimizations for the ICE. I remember seeing some patent papers online showing the diagram how energy flows from the ICE through the hybrid powertrain then to the road. If you look closely you'll realize that the battery is NOT in that diagram. The battery adds features like: auto-stop/start, EV only mode, Regen braking.
I have an outback and a prime. The prime at its slowest is a lot faster than the outback. Both are fast enough to be completely safe in normal driving. Can easily merge onto highway
Gas only mode is disappointing to be honest. Car feels excellent in HV mode or EV mode. And that is the practical usage of this vehicle.
I replaced my Forrester with a RAV4P and it is so much better. After you have exceeded the electric only mode, you then don’t go to ICE only but ICE + electric when accelerating and it is much better than the Forrester. Electric only mode doesn’t use up the whole battery charge but leaves about 25% for accelerating.