I got used to the "B" mode that brakes and recharges when throttle is off. I understood that it is not real brakes that are in action but it is done by battery/engine ? Are there any negative aspects of this mode (regarding brakes, engine, battery etc. usage) or it is perfectly ok and can be used all the time without any problem?
T8 Recharge - does "B" gear mode have any negative aspects ?
Ivos
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22.5 Black S60 R-Design, Extended Range T8
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I believe Coasting in B is a mixed bag. On one level it will generate energy to battery. It’s a lot more efficient to be in B than to use physical brakes. However the round trip to battery and back into velocity will not be all thaf effecient. . If one is on the highway and takes their foot of the accelerator during the journey (and without braking) it will be net more efficient than coasting in B which involves significant regen braking and the reacceleleration. I have read this is around 70 effeciency whereas true coasting in D is probably in 90% range especially in electricity only.
If one is in B and lightly tapping the accelerator it might be fairly close. Some have referred to this last piece as coasting.
Can you please clarify your definition of coasting here?
If one is in B and lightly tapping the accelerator it might be fairly close. Some have referred to this last piece as coasting.
Can you please clarify your definition of coasting here?
2023 V90 T6 Recharge Ultimate with in Thunder Grey with Blonde Nappa
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You need to learn to read your own posts!! Your original post stated you wouldn't have any coasting, which is untrue. BRAVO!!
22.5 Black S60 R-Design, Extended Range T8
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let’s see if we can find some common ground: regenerative braking is better than mechanical brakes. B will pursue this at the cost of traditional coasting. In D, regen braking also occurs but is less aggressive. There are times when B or D Will basically be a wash. And other times with B where constant slowing down is needed, where less mechanical braking will be involved. other trips D will maintain speed more and allow for periods of true coasting and only anoccasional tap on the brakes is needed so it’s better than those circumstances. A drivet that is skilled in B, might be able to mitigate this advantage by keeping the car at a similar steady speed.I don't think anyone is disputing that the ER regen intensifies when you lift your foot. This is B mode.
The question is about your statement that the ICE doesn't turn off when coasting in D mode (assuming it has reached operating temperature and is not running to keep the cabin warm). True, I don't have a T8 (did test drive), but to not turn off the ICE when coasting seems brain dead, and every hybrid (plug-in or otherwise) I've driven does this (again, with some exceptions around the exact operating conditions). Granted, B mode could be more aggressive in when it turns off the ICE, but additional seconds of ICE vs. regen inefficiency seems like, at best, a wash.
If you like how B mode operates, go ahead and use it, but I'm still skeptical about its supposed MPG and brake wear benefits in normal driving - unless normal driving involves long-ish hill descents or normal driving means using the brakes as an ON/OFF switch
also in circumstances B is less work and in othered D is less work. In work I am talking about the drivers efforts. If one enjoys B, which several do, it might not feel like it’s extra effort.
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Ugh! This is precisely why the government, and thus, manufacturers, evaluate powertrains over a specific speed-vs.-time drive cycle.
Think about what you are saying... You are saying "If I drive 70 mph in D, and let of the gas at mile marker XX, I find that I enter the curve at 60 mph, which is perfect".
"Now, when I drive in B and let off the gas at mile marker XX, I'm entering the curve at 50 mph, which is too slow, so I have to step on the gas to get back to 60 mph." Well, of course that's inefficient.
That's not how you drive in the real world and you shouldn't compare D to B using a scenario like that.
Think about what you are saying... You are saying "If I drive 70 mph in D, and let of the gas at mile marker XX, I find that I enter the curve at 60 mph, which is perfect".
"Now, when I drive in B and let off the gas at mile marker XX, I'm entering the curve at 50 mph, which is too slow, so I have to step on the gas to get back to 60 mph." Well, of course that's inefficient.
That's not how you drive in the real world and you shouldn't compare D to B using a scenario like that.
22.5 Black S60 R-Design, Extended Range T8
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For reference, I am getting better with driving in B. I was able to get .6KWH from the system on 8 mile drive and use 4 KWH gross so 3.4 Net KWH. Yesterday, i had used 5 gross and little more regen of .7. There might be other factors so this data point does not establish a pattern but I could feel that i was using the gas pedal better i.e keeping the speed without having to let of the accelerator or redeploy my foot a stronger clip. Yesterday was much less smooth.
Also. I don't think there is anyway to avoid using mechanical brakes for going from <4 to 0, which I have to on the streets and even on the Highway from time to time. I hate using brakes so B addresses much of that but with severe stop and go highway traffic or intersections, I think we are forced to use mechanical brakes at certain points.
If i am doing the math incorrectly, please advise.
i did have 1 trip earlier in the week which was 3 KWH net (3.5KWH gross and.5 regen) and that was in D so that is my target to beat, if possible. seemed to be as much traffic based on the trip time but i wasn't paying as much attention to the process as I am now. for me this is fun and I like debate and education but i don't like conflict, when it can be avoided.
In another forum, there are people having issues with their HVCH and some posters seem to be indifferent to the issue. I don't like to see anyone go through trouble with their vehicles. we buy/lease these to make our lives easier and/or more interesting.
Also. I don't think there is anyway to avoid using mechanical brakes for going from <4 to 0, which I have to on the streets and even on the Highway from time to time. I hate using brakes so B addresses much of that but with severe stop and go highway traffic or intersections, I think we are forced to use mechanical brakes at certain points.
If i am doing the math incorrectly, please advise.
i did have 1 trip earlier in the week which was 3 KWH net (3.5KWH gross and.5 regen) and that was in D so that is my target to beat, if possible. seemed to be as much traffic based on the trip time but i wasn't paying as much attention to the process as I am now. for me this is fun and I like debate and education but i don't like conflict, when it can be avoided.
In another forum, there are people having issues with their HVCH and some posters seem to be indifferent to the issue. I don't like to see anyone go through trouble with their vehicles. we buy/lease these to make our lives easier and/or more interesting.
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I think an important aspect of B Mode is that it encourages the driver to make more and better use of regen by making it easier to use the brakes less.
It's been pointed out endlessly in this thread that while it's possible to duplicate B's off-throttle regen by lightly using the brakes, it's more difficult and less convenient, so it's reasonable to expect B Mode to be beneficial in casual everyday use.
I'm still not convinced there is any downside to B-Mode except for unusual circumstances...
- When driving on slippery roads, such as ice, slush, or snow.
- During a downhill drive.
- If you fill your car with heavy baggage or cargo.
22.5 Black S60 R-Design, Extended Range T8
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Great article; simple and accurate. Thanks for posting.
I think an important aspect of B Mode is that it encourages the driver to make more and better use of regen by making it easier to use the brakes less.
It's been pointed out endlessly in this thread that while it's possible to duplicate B's off-throttle regen by lightly using the brakes, it's more difficult and less convenient, so it's reasonable to expect B Mode to be beneficial in casual everyday use.
I'm still not convinced there is any downside to B-Mode except for unusual circumstances...
One-Pedal Driving: Everything You Need to Know - Kelley Blue Book (kbb.com)
- When driving on slippery roads, such as ice, slush, or snow.
- During a downhill drive.
- If you fill your car with heavy baggage or cargo.
To the bulleted list, maybe add highway driving when lifting your foot of the accelerator slows you down too much. The latter point can be moderated with experience.
The ones listed in the article are potentially unsafe my point is for optimization.
I agree with your and the article's implied idea that we should be using B more for establishing battery regeneration.
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Finally a clear explanation, thank you
I think an important aspect of B Mode is that it encourages the driver to make more and better use of regen by making it easier to use the brakes less.
It's been pointed out endlessly in this thread that while it's possible to duplicate B's off-throttle regen by lightly using the brakes, it's more difficult and less convenient, so it's reasonable to expect B Mode to be beneficial in casual everyday use.
I'm still not convinced there is any downside to B-Mode except for unusual circumstances...
One-Pedal Driving: Everything You Need to Know - Kelley Blue Book (kbb.com)
- When driving on slippery roads, such as ice, slush, or snow.
- During a downhill drive.
- If you fill your car with heavy baggage or cargo.
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Only REAL differences in B mode vs D mode ignoring what you need to do with each pedal to slightly decel/coast (again, on MY 2019) is slight difference in how cruise control reacts to overspeed, and when the rear brake lights come on.
Otherwise it is a convenience (and I love it, but still turn it off on some "dippy" roads).
I even have it down to a science on the exit off the bypass near me. I know if I crest the last hill at XXmph, put it in D, it will coast down to the exit ramp, up the ramp, and at a certain spot on the road, I pull back to B, and it decels down to about 10-12MPH before I get to the light at the top of the ramp which hopefully will change. After you get below that speed B doesn't do anything anyway. (But brake pedal obviously will)
Otherwise it is a convenience (and I love it, but still turn it off on some "dippy" roads).
I even have it down to a science on the exit off the bypass near me. I know if I crest the last hill at XXmph, put it in D, it will coast down to the exit ramp, up the ramp, and at a certain spot on the road, I pull back to B, and it decels down to about 10-12MPH before I get to the light at the top of the ramp which hopefully will change. After you get below that speed B doesn't do anything anyway. (But brake pedal obviously will)
22.5 Black S60 R-Design, Extended Range T8
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You seem like a pretty contemplative driver. This comment as well as some of the hypermile posts suggest this. It great I am learning a lot from you. thanks.
How can you go back into D quickly? I have done exactly what you describe but not sure how to get back to D if wanted this.
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Just move the shifter back (again I have a 2019, newer ones are different I think)
Mine starts in Park or whatever, then first move puts it in N (either way) Then away for R and towards you for D, then again for B and again for B1(2,3,4...) (downshift mode). Then if you push back, it goes back to D, even if in downshift mode.
New ones are different I think because of EVERY review had to bitch and whine about having to move the shifter twice to get from Park to R or D. When in reality, most cars used to take 3 positions to get to D...
22.5 Black S60 R-Design, Extended Range T8
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When I have tried shifting out of B, I believe I go into N. I will try again.
any 2022.5 or 2023 T8's have an answer. As you have said Pioneer, we need a T8 forum.
MY22.5 XC90 Recharge Extended Range in Birch Light and Blond, Lounge, Advanced, Climate, Air and B&W
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My 22.5 XC90 Recharge ER works the same way. However, while driving in D, I don't bother with B1, B2, etc. I simply pull back on the shifter to switch to B and then pull back again to switch back to D. Very simple. If I push to the left I can engage B1, etc., but don't routinely do that.
22.5 Black S60 R-Design, Extended Range T8
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I see it now. Thanks
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That is nice, the 2019 only has pull back, you can force downshifts, but not upshifts (without paddles, and S90, no paddles
) It doesn't have a side to side I see a huge difference in "B" mode in pre-ER Volvo PHEVs vs. ER Volvo PHEVs. I test-drove a ton of different pre-ER Volvo PHEVs and was so disappointed that I never could buy one, despite desperately wanting to, because I found the drivetrains and response and range so poor. But the ERs are completely different. Pre-ER, there was no one-pedal driving. I really was also rather anti-one-pedal driving from my limited experiences in test-driving various BEVs from Teslas to Volvos/Polestars. But once I got my 2022 ER, I immediately starting experimenting with the one-pedal driving and quickly came to really prefer it over non-one-pedal driving -- so much so that I keep it in B all the time, even when at highway speeds. When I drive non-one-pedal cars (or my XC60 in D mode), I now get frustrated!
You do indeed learn to use the one-pedal slowing down to maximum advantage. At highway speeds, it slows down very gradually until you get to lower speeds, at which time it kicks in more strongly. A good one-pedal user is much safer, I think, than one who has to depend solely on the brake pedal to slow down or stop; I'm convinced of that after driving more than 5 months now in one-pedal mode. I get much better regen with B mode than in D mode. Note that I drive about 75% of my miles in all-electric ("Pure") mode, meaning mostly below 45 mph in city/suburban traffic -- for which B is perfect, and indeed Volvo recommends driving daily in B mode for urban driving. But I've gone that further step in experimenting with D vs. B when driving at highway speeds, and am not convinced that D is better (and may be worse) at highway speeds that are not stop-and-go.
In reading this thread, I've also come to reflect more on the concept of "coasting", as I drive in B mode at highway speeds -- wondering really when I'd ever need to "coast" without one-pedal driving. Yeah, you go downhill and take your foot off the accelerator in D mode, but in "B" mode with the right touch (which becomes second nature after a few weeks of full-time use), I find coasting to be easier and more natural in B mode. In D mode you'll often speed up too much going down a hill, which can only be rectified by stepping on the brake pedal, while in B mode, you just let up on the accelerator a little and maintain speed. And in ACC, I wonder if B might also not be better than D mode for better regen and less brake use.
Note that regen is a much faster charger of your traction battery than is AC charging from the wall; I often get 1-2 miles of range back in my battery going down a steep hill on an expressway here (daily route to work) in about a minute of driving, while charging in my garage will take 20-40 minutes to get that much charge back in the battery. So I seriously don't see the reason to ever drive in D mode with an ER PHEV. Non-ER Volvos do not operate this way -- regen is not as profound by a long shot, and there's no real one-pedal driving. Night-and-day difference.
You do indeed learn to use the one-pedal slowing down to maximum advantage. At highway speeds, it slows down very gradually until you get to lower speeds, at which time it kicks in more strongly. A good one-pedal user is much safer, I think, than one who has to depend solely on the brake pedal to slow down or stop; I'm convinced of that after driving more than 5 months now in one-pedal mode. I get much better regen with B mode than in D mode. Note that I drive about 75% of my miles in all-electric ("Pure") mode, meaning mostly below 45 mph in city/suburban traffic -- for which B is perfect, and indeed Volvo recommends driving daily in B mode for urban driving. But I've gone that further step in experimenting with D vs. B when driving at highway speeds, and am not convinced that D is better (and may be worse) at highway speeds that are not stop-and-go.
In reading this thread, I've also come to reflect more on the concept of "coasting", as I drive in B mode at highway speeds -- wondering really when I'd ever need to "coast" without one-pedal driving. Yeah, you go downhill and take your foot off the accelerator in D mode, but in "B" mode with the right touch (which becomes second nature after a few weeks of full-time use), I find coasting to be easier and more natural in B mode. In D mode you'll often speed up too much going down a hill, which can only be rectified by stepping on the brake pedal, while in B mode, you just let up on the accelerator a little and maintain speed. And in ACC, I wonder if B might also not be better than D mode for better regen and less brake use.
Note that regen is a much faster charger of your traction battery than is AC charging from the wall; I often get 1-2 miles of range back in my battery going down a steep hill on an expressway here (daily route to work) in about a minute of driving, while charging in my garage will take 20-40 minutes to get that much charge back in the battery. So I seriously don't see the reason to ever drive in D mode with an ER PHEV. Non-ER Volvos do not operate this way -- regen is not as profound by a long shot, and there's no real one-pedal driving. Night-and-day difference.
22.5 Black S60 R-Design, Extended Range T8
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I am getting used to B as well and am finding that my miles per KWHis improving. I think 3 miles per KWH is about my norm. Can someone please verify the math. Do we have subtract the miles regen from the KWH used to get the net usage?
This seems the most logical to me but could see how the KWH is also a net figure.
also is there a way yo see a charging log?
This seems the most logical to me but could see how the KWH is also a net figure.
also is there a way yo see a charging log?
My 2021 T8 does the same
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In the Volvo cars app, there are data points in the Driving Journal for fuel consumption, electric consumption, and electric regeneration for each trip.
The Driving Journal data can be exported to a csv file, including an MS Excel file based on a date range.
Of course, the Volvo Car App has an annual subscription fee.
FWIW: On a related note for all posters, the newer Recharge versions (MY20+) have benefited from the continuous improvement kinetic energy recapture efforts (e.g., mild hybrid, GPS assisted hybrid optimization, maybe B-mode).
So, yes, kinetic regeneration overall has improved since the MY16-MY19 T8 models.
Sent from my BE2028 using Tapatalk
22.5 Black S60 R-Design, Extended Range T8
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Very helpful, i just want to see if there is anyway to see if app can tell how much charge the car recived on a regular basis . Like the driving journal but for charging. Does this exist?
Steingold offers a $180 rate for an app renewal subscription. What functionality if any does the app have without the renewal?
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