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Discussion Starter · #1 ·
Based upon what I've read here and elsewhere, my car seems to behave a little differently than some others.

Typically, my SOC stays at 7 bars (green) or 6 bars (blue). It is not uncommon at all for my battery to show 8 bars, which is "fully" charged. I see this several times a week at least. Very rarely does it go below 50% and the only time I've seen pink was when I installed my EV switch and was testing it.

I'm happy with my MPG (~47) and it's comparable to what others in my neck of the woods are getting, so I'm not really concerned.

Does this mean I have the "upgraded" software I've heard mentioned? The car is two months old. I'm tempted to start being more aggressive with my EV switch to take advantage of my seemingly freely charging system.

The only thing I'm worried about is that I'm missing out on some regen once the battery really gets full. It does get full eventually - as in no more green arrows going back to the battery when slowing/braking. However, I've only seen this condition once or twice.

BTW- I had a nice little Prius moment this morning. I was in EV mode and hit 34 MPH. I heard the triple Be-Be-Beep as EV mode was overrode, but the ICE didn't come on - it went right into "stealth" mode. Woo Hoo!


DGStan
 

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In all likelyhood you could, cautiously, benefit from increased EV button use. It sounds like you must do a lot of regen to maintain the SOC that high. If you're able to anticipate terrain where you will be getting a lot of regen you could potentially use the EV button, instead of ICE, and avoid ICE ever starting until that regen situation is over.

Just keep in mind, more often than not your car is a better regulator of the system than you will be. Unless you're quite sure you are doing something better than the car is it's better to let the car decide. I'd also guess that 2 months into ownership you've still got a way to go before you have a solid understanding of how to maximize the efficiency of your car.

Finally, if you're seeing all green bars fairly often you might not be driving the car in it's most efficient way. That is, you may be keeping your rate of acceleration too slow and some of the extra energy is going to the battery instead of directly to the wheels...that's fine once in a while, and the way the system is supposed to work, but it's not as efficient as driving with all the ICE power going to the wheels.

I tend to accelerate from stop this way:
1)Brisk start...usually showing around 15mpg-20mpg on the Energy screen and using both ICE and Battery power--I use this up to about 30-35mph.

2)Back off and find the Dead Band No arrows to or from the battery...This is the most efficient zone...ICE RPM near ideal, not losses from or to the battery. I keep this zone as much as possible up to my cruising speed (conditions allowing)

3)Foot totally off pedal and hit Cruise control if I'll be maintaining my set speed and let the CC handle it from there. I'll use 'quasi-neutral' if I have a hill to go down or a stop approaching.

Good luck.
 

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dgstan said:
Typically, my SOC stays at 7 bars (green) or 6 bars (blue). It is not uncommon at all for my battery to show 8 bars, which is "fully" charged. I see this several times a week at least. Very rarely does it go below 50% and the only time I've seen pink was when I installed my EV switch and was testing it.
How often do you monitor it? For a while I was mostly driving on the consumption screen and only flipping to Energy at the beginning and end of the drive, and I thought my battery was always at 6-7 bars. With the AC working more often, and my spending more time looking at the Energy screen, I now see it often dipping below halfway. It usually comes back up as I get into more stop and go at the end of the drive. The only time I've recently been "in the pink" was circling around at the airport at 15 mph for 20 minutes; natural regen seems to rarely get it there.
 

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Discussion Starter · #4 ·
Astrowoman said:
dgstan said:
Typically, my SOC stays at 7 bars (green) or 6 bars (blue). It is not uncommon at all for my battery to show 8 bars, which is "fully" charged. I see this several times a week at least. Very rarely does it go below 50% and the only time I've seen pink was when I installed my EV switch and was testing it.
How often do you monitor it? For a while I was mostly driving on the consumption screen and only flipping to Energy at the beginning and end of the drive, and I thought my battery was always at 6-7 bars. With the AC working more often, and my spending more time looking at the Energy screen, I now see it often dipping below halfway. It usually comes back up as I get into more stop and go at the end of the drive. The only time I've recently been "in the pink" was circling around at the airport at 15 mph for 20 minutes; natural regen seems to rarely get it there.
It's my default screen. It's up 95% of the time, so I'm not missing anything.

Maybe it's the gentle rolling hills of S. Orange County that help keep the battery charged, but I don't know. Maybe someone else down here can confirm of deny my findings.


DGStan
 

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Discussion Starter · #5 ·
efusco said:
In all likelyhood you could, cautiously, benefit from increased EV button use. It sounds like you must do a lot of regen to maintain the SOC that high. If you're able to anticipate terrain where you will be getting a lot of regen you could potentially use the EV button, instead of ICE, and avoid ICE ever starting until that regen situation is over.

Just keep in mind, more often than not your car is a better regulator of the system than you will be. Unless you're quite sure you are doing something better than the car is it's better to let the car decide. I'd also guess that 2 months into ownership you've still got a way to go before you have a solid understanding of how to maximize the efficiency of your car.

Finally, if you're seeing all green bars fairly often you might not be driving the car in it's most efficient way. That is, you may be keeping your rate of acceleration too slow and some of the extra energy is going to the battery instead of directly to the wheels...that's fine once in a while, and the way the system is supposed to work, but it's not as efficient as driving with all the ICE power going to the wheels.

I tend to accelerate from stop this way:
1)Brisk start...usually showing around 15mpg-20mpg on the Energy screen and using both ICE and Battery power--I use this up to about 30-35mph.

2)Back off and find the Dead Band No arrows to or from the battery...This is the most efficient zone...ICE RPM near ideal, not losses from or to the battery. I keep this zone as much as possible up to my cruising speed (conditions allowing)

3)Foot totally off pedal and hit Cruise control if I'll be maintaining my set speed and let the CC handle it from there. I'll use 'quasi-neutral' if I have a hill to go down or a stop approaching.

Good luck.

Thanks for the tips Doctor. That's what I'm looking for - sage advice from the Prius gurus. I'll test your thoughts regarding the slow starts.


DGStan
 

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dgstan said:
Typically, my SOC stays at 7 bars (green) or 6 bars (blue). It is not uncommon at all for my battery to show 8 bars, which is "fully" charged.
The target SOC is normally 60% and it is in the 6th bars. So it is normal.
Does this mean I have the "upgraded" software I've heard mentioned?
No.
The only thing I'm worried about is that I'm missing out on some regen once the battery really gets full. It does get full eventually - as in no more green arrows going back to the battery when slowing/braking. However, I've only seen this condition once or twice.
The upper limit is controlled at 80% of SOC. The 8 bars does not mean really full, we have still 20% margin, but we need this margin for the battery life.
So, the battery won't be charged anymore at the top of 8 bars.
BTW- I had a nice little Prius moment this morning. I was in EV mode and hit 34 MPH. I heard the triple Be-Be-Beep as EV mode was overrode, but the ICE didn't come on - it went right into "stealth" mode. Woo Hoo!
Same as mine. The EV mode is canceled at 34 MPH, but we can do stealth up to 42 MPH.

Regards,
[email protected]
 

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efusco said:
I tend to accelerate from stop this way:
1)Brisk start...usually showing around 15mpg-20mpg on the Energy screen and using both ICE and Battery power--I use this up to about 30-35mph.
A Japanese Mileage Master always says "Do not use the Battery power during acceleration".
The ICE only acceleration is better for good mileage.
It is good strategy to reserve the battery power for coasting.

Regards,
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ken1784 said:
A Japanese Mileage Master always says "Do not use the Battery power during acceleration".
The ICE only acceleration is better for good mileage.
It is good strategy to reserve the battery power for coasting.

Regards,
[email protected]
OK, I've been thinking about this for days... how the heck do you do that? My car adds electric whenever it wants more torque. The only time I seem to be able to get ICE-only acceleration is if I'm already at a pretty good speed and I just want to tweak it up a hair. Conversely, the only time I see electric-ony cruise is at very slow cruising speeds. I do often get moderate to high speed cruising on gas only. Am I missing something?
 

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He was saying not to use battery power for boost. You will see electric power going from MG1 to MG2. You'd have to in order to get the full power capability of ICE, since it is split.

Rule of thumb, if your MPG is about 20 during acceleration, you are using very little battery power.
 

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Astrowoman,
It can be done, but from a dead stop it's very very tricky. If I'm careful I can usually get into the 'dead-banding' (ICE to wheels with no battery charge or discharge) by about 20-25mph...from that point it's pretty slow acceleration until you get up to about 40mph. At that point I find I have to usually depress the accelerator further to keep in the 'dead-band' range or I'll start spilling power back to the battery.

Electric only cruise is tougher...I find I can only get it at relatively slow speeds <45mph on level terrain or at higher speeds on down-hill inclines....though usually I use gliding (quasi-neutral as per the other thread).

This is going to be one of those circumstances you don't like at all. It does take a lot of attention to the Energy screen to find the dead-band and then stay in it. I have 3 or 4 places along my usual commute that I find it practical to try to use dead-banding but I haven't for quite a few months due to the increased attention it requires to do so (much more than gliding does IMO).
 

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DanMan32 said:
He was saying not to use battery power for boost. You will see electric power going from MG1 to MG2.
Translate MG1,2 please?

efusco said:
This is going to be one of those circumstances you don't like at all. It does take a lot of attention to the Energy screen to find the dead-band and then stay in it. I have 3 or 4 places along my usual commute that I find it practical [...]
Yeah. I can sometimes play with these ideas on weekends, but very unlikely in weekday traffic. Just too distracting.

But, hey, the mileage isn't THAT bad even if you "just drive it!" Though my car never recovered from the start the current tank had -- circling around the airport on battery long enough to get into the red zone, then driving uphill all the way home (18 miles).

I wonder what the accident rate is for new, tech-y Prius owners. Has the potential to be even worse than cell-phone use.
 

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MG = Motor Generator

MG1 is the smaller MG usually used for starting up the ICE
MG2 is the larger for regen braking/powering the ICE
 
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