[Question] Can you generate electric while driving to a depleted battery?

I am confused. I thought B mode spun the engine to dissipate some energy, reducing charge to the pack.

i know my Gen 4 radar cruise tends to use B mode to decelerate. I reclaim more charge by braking normally on a downhill stretch of my work commute. The downhill is nowhere large enough to need B mode. There is no way for the radar cruise system to know that though.

 

Only if the car is in Hv mode. In Ev mode, it's all regen.

Same with radar cruise in the Prime - in Ev mode, it's all regen.

 

it is different in the plug ins v non plug ins. but to be honest, i haven't followed the discussion closely enough to explain it.
i suppose the reason is the larger battery enabling more regen when available. why just spin the engine to slow down if you can charge the battery?

 

[QUOTE="bisco, post: 2695365, member: 5889"
i suppose the reason is the larger battery enabling more regen when available. why just spin the engine to slow down if you can charge the battery?[/QUOTE]
That reasoning could apply to the Liftback too since the systems know the pack;s current SoC.

 

you don't think it charges the battery fully, before going into engine spinning mode to blow off steam?

 

I know the cruise does not. I usually increase my charge from 5 to 7 bars down that slope. The cruise keeps it at 5, iiRC.

 

Except that the liftback's much smaller battery can accept much less regen for a shorter time.

 

i don't know if cruise does in the pip either, but i thought we were discussing b mode.

 

I was responding to Mayank's question about using B mode as you approach a stop. You can do that in a PiP to stack the SOC, but I'm just pointing out that you can stack the charge in that situation more conveniently and just as effectively with the brake pedal.

Force charging on the Prime is more sophisticated and easier for the driver.

 

As an owner of a Gen 3 Prius, I sometimes regret not buying the PIP in favor of the moonroof and solar package. Our summer travels usually take us over a mountain range that creates anxiety as I do everything I can to keep the car under control and not blow its rods through the hood. It is crazy how the engine is designed to dissipate the energy by revving up. I don't know of a way to deplete the battery before beginning the long downhill madness.

Based on the discussion here, I am under the impression that the PIP's computer is designed to regen only the first 1.x kwatt of battery of the 8.x kwatt capacity under normal driving conditions. Only extreme regen, like large downhills, will the computer put the energy into the upper part of the battery. So driving 400 highway miles will not get you any upper battery in the PIP. But the Prime will continue to charge the entire battery as long as there is energy being produced, ICE or gravity, correct?

Let's say you're at 2 bars on your battery, around the time the ICE is forced to turn on. Is the mpg on average going to be lower because more of the power being generated is sent to the battery to put some charge back in? Once the battery has some charge it can then begin to assist the ICE to increase mpg, right? Wonder why the PIP couldn't slowly fill the entire battery over a long distance. Are there two physical separate batteries in the PIP or is it simply software that is creating the limitation?

Thanks.

 

Crazy? Traditional non-hybrid cars will do the same thing. In fact, it is a legal requirement to have a lower gear than regular D (in automatic transmissions -- downshifts are inherently available in manual transmissions) to do so.

 

No. Prime (gen-2) behaves the same was as PHV (gen-1). When the plug-supplied electricity is used up, it will switch to HV mode and remain there. Prime offers the ability to force-charge the battery-pack, but that requires you to make that choice.

When descending down a mountain, both will capture the energy in the form of generating electricity. But that's an exception to the rule... something only those dealing with altitude changes will ever experience.

In other words, the system strives to deliver the highest overall MPG using a combination of resources. It won't just recharge hoping you'll be able to use that electricity later. HV driving takes advantage of the back & forth design of the hybrid system.

That would result in a net loss, wasting the benefit the hybrid system offers.

Both generations have a single battery with software controlled limitations.

Watch these 2 videos I filmed last weekend for some comprehensive info on how the system works. There are some step hills and a 1.5 mile decedent into the valley.

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