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Discussion Starter · #1 ·
When the Hybrid System Indicator is in the charging area during braking, are the motors used exclusively for braking until the needle hits the max limit or are the brake pads always being applied with the resistance of the motors?
 

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I know from my Prius, I assume my Rav4 is the same; The friction brakes are used in 2 ( actually 3 ) situations:
-Below about 11 km/h ( 7 mi/h ).
-Emergency braking.

The 3rd situation is the parking brake.
 

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When the Hybrid System Indicator is in the charging area during braking, are the motors used exclusively for braking until the needle hits the max limit
Correct. Friction brakes are blended if you exceed max charging. The faster you are going, the easier it is to make that happen.
 

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Discussion Starter · #4 ·
I thought I'd add another question to this thread:

When the battery is fully charged on the highway, how does the system prevent the battery from getting overcharged, especially when coasting or braking? I haven't watched the energy monitor religiously, but power low always seems to be going toward the battery on the highway even when full. Not saying this is a problem since Toyota knows better than I do, but I'm just curious about how the battery protects itself from overcharge.
 

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I thought I'd add another question to this thread:

When the battery is fully charged on the highway, how does the system prevent the battery from getting overcharged, especially when coasting or braking? I haven't watched the energy monitor religiously, but power low always seems to be going toward the battery on the highway even when full. Not saying this is a problem since Toyota knows better than I do, but I'm just curious about how the battery protects itself from overcharge.
I'm not sure a DC battery can be "overcharged". From what I know there's a max capacity for dry cells and they just won't hold any more charge once at capacity.
Does anyone else have any electrical experience with this?
 

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I thought I'd add another question to this thread:

When the battery is fully charged on the highway, how does the system prevent the battery from getting overcharged, especially when coasting or braking? I haven't watched the energy monitor religiously, but power low always seems to be going toward the battery on the highway even when full. Not saying this is a problem since Toyota knows better than I do, but I'm just curious about how the battery protects itself from overcharge.
The battery is never over an 80% SOC. Once its at its max allowed SOC, regen braking is turned off. Engine braking is forced, and friction brakes are used.
 

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The battery is never over an 80% SOC. Once its at its max allowed SOC, regen braking is turned off. Engine braking is forced, and friction brakes are used.
I've seen my hybrid battery indicator light up all full (8 bars) only one time.
It was during a 5 mile downhill freeway at 5% downgrade.
That's the only time I've seen the hybrid battery charge up to full due to purely coasting.

Usually the ICE shuts off to stop recharging the hybrid battery at 6 bars.
 

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I've seen my hybrid battery indicator light up all full (8 bars) only one time.
It was during a 5 mile downhill freeway at 5% downgrade.
That's the only time I've seen the hybrid battery charge up to full due to purely coasting.

Usually the ICE shuts off to stop recharging the hybrid battery at 6 bars.
This happened to me too on a long downgrade where the battery said it was fully charged, but I am not inclined to believe what the gauge says 100 percent. The system is designed to protect the battery so its unlikely to charge fully in a system that is constantly utilizing the battery.
 

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8 bars represents an 80% SOC.
2 bars represents about a 40% SOC.

So the actual operating range is between 40-80% SOC.
 

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I'm not sure a DC battery can be "overcharged". From what I know there's a max capacity for dry cells and they just won't hold any more charge once at capacity.
Does anyone else have any electrical experience with this?
All battery types that I know are DC, and all of them can be overcharged if the multiple built-in fail-safes fail to stop the overcharge.

It's not just the Note 7, all cell phones would explode and catch fire if overcharged. :D
 

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How low on the charge area can you go before it starts to mix in friction brakes? The acc radar "brakes" rather hard at times.


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How low on the charge area can you go before it starts to mix in friction brakes? The acc radar "brakes" rather hard at times.
All the way to the bottom. Friction brakes are only used when you reach max charge.

If you're asking whether its best to use max charging regularly, the answer is no. All braking is bad for efficiency, regen braking is less bad. Use the middle mark on the charging gauge as your guide and try to stay above that as much as possible. IOW drive like there's a raw egg on the brake pedal.
 

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The acc radar "brakes" rather hard at times.
That's a function of the algorithm. The radar senses how fast the gap between you and the car in front is closing and brakes proportionately. You may have noticed that a car can pass and pull in right in front of you and as long as he's accelerating (i.e., the gap is getting bigger), the radar cc will maintain your speed. I'll admit that it is a little disconcerting to feel the brakes being applied when your foot is on the gas pedal. Definitely takes some getting used to if you (like me) have not experienced radar cc before.
 

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That's a function of the algorithm. The radar senses how fast the gap between you and the car in front is closing and brakes proportionately. You may have noticed that a car can pass and pull in right in front of you and as long as he's accelerating (i.e., the gap is getting bigger), the radar cc will maintain your speed. I'll admit that it is a little disconcerting to feel the brakes being applied when your foot is on the gas pedal. Definitely takes some getting used to if you (like me) have not experienced radar cc before.
Is it recommended to keep your foot on the gas pedal while using radar acc?
 

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Um, no. If you're using cruize control, why would your foot be on the gas pedal? Foot should off the pedals.

Is it recommended to keep your foot on the gas pedal while using radar acc?
 

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I've seen my hybrid battery indicator light up all full (8 bars) only one time.
It was during a 5 mile downhill freeway at 5% downgrade.
That's the only time I've seen the hybrid battery charge up to full due to purely coasting.

Usually the ICE shuts off to stop recharging the hybrid battery at 6 bars.
We were travelling in Yellowstone a few weekends ago and were going down a mountain pass with acc engaged. Once the battery indicator hit "full", the EV light turned off, the ICE kicked on, and the ICE started "engine braking" (high rpm). Not sure what the exact criteria for that behavior is but that was what we noticed. There were no charge indicators going towards the battery presumably because it was full which makes sense that it would cease regen braking if the battery is full.
 

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We were travelling in Yellowstone a few weekends ago and were going down a mountain pass with acc engaged. Once the battery indicator hit "full", the EV light turned off, the ICE kicked on, and the ICE started "engine braking" (high rpm). Not sure what the exact criteria for that behavior is but that was what we noticed. There were no charge indicators going towards the battery presumably because it was full which makes sense that it would cease regen braking if the battery is full.
Did you have cruise control on and speed set?
 
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