Will hybrid battery fully charge while driving?

Yes and No. Yes if you switch it to Charge mode. No if you leave it in HV mode.

 

Switching to Charge mode is usually not recommended, due to the energy losses of burning the gasoline to make electricity to charge the battery to then power the electric motor to move the car. Just burning gasoline to move the car is usually best, but there are some scenarios where Charge mode make sense, like building battery charge to be used in city driving following a long highway drive. The Prime is designed to be charged from the power grid.

After the battery is discharged to near its minimum state of charge (around 20%), the Prime reverts to behaving like a standard Prius, keeping the battery charged at about 20%, while varying up and down a bit.

 

Charge mode can only charge the battery up to 80%. Plugging in is the only way to get 100%. Charge mode is engaged by holding down the hv/ev button.

Posted via the PriusChat mobile app.

 

Even in EV mode you can gain some charge, granted it's not much but it's something. With the cold weather I've found myself manually switching to EV when on the highway heading home if the charge is 15% or lower. I wont get home without ICE coming on at some point, better to do that on the highway going a steady speed then in stop and go traffic (at least that's my understanding). I often gain 2-3% by the time I get off the highway which is just enough to make it home once I hit city streets again.
In my mind it's kind of "opportunity charging" meaning it's not actively charging all the time but when ever ICE (or regen braking) can throw a little extra charge in it does.

I have not used the EV charging mode. After hearing how much it affects MPG I havent had a need for it.

 

it's a plug in, plug it in to charge

 

go for it, depends on the length though. after 10-15 feet, i prefer a 12 ga extension.

if you vacation in mountain country, you can pick up some serious charge on the backside

 

As already pointed out, Charge mode can do (most of) this.

But except in special circumstances, this is pointless. It causes you to burn the same gasoline that you were trying to save by buying a Plug-In car in the first place. Major charging should be done only by plugging into the electric grid.

... or by long mountain descents that you were going to travel anyway, plug-in car or not.

 

At what speed would forcing charge mode be most beneficial? 30mph would be maddening, but for those "going at the limit", what would the dip in mpg be? -5 mpg, -10 mpg? Would charge mode while driving down a long highway descent be most advantageous? Should be fun for the hypermillers.

[EDIT]- opps, didn't see fuzzy1's last sentence there.

 

I'm not yet a plug-in owner, so can't give a first-hand answer. But it seems that speed and mpg dip are not useful windows to view this. Force charging generally won't save on gasoline overall (current owners may be able to post some exceptions), so it is best left to other situations where you have other reasons to not run the ICE but lack plug-in opportunity. E.g. noise (leaving / arriving / parading silently), emissions (future departure from enclosed parking garage), etc.

I don't believe this needs Charge mode, it comes automatically with the braking regeneration. And with my travel pattern including many long descents that greatly exceed regular Prius regen capacity, I'd be making great use of this feature.

 

True, but then using regen will decrease your speed or momentum which becomes counterproductive for highway or motorway driving. The same goes for EVs that lack a glide ability.

Anywhoo, what I had in mind was activating charge mode when coming down the other side of the mountain. Where I live, there's barely any that will last more than 5 minutes. But at least when I do in my Gen 2, it can average over 70 mpg (imp gal) over that time interval at considerably fast speeds with the slightest throttle on. On my OBDII the 1.5l was making a fair 20 amps ticking away at 1650 rpm until it stopped that charging at 65% SOC. It's a Super Highway Mode some have coined a decade or more back on this forum site.

I know in the US and Canada, there's much larger mountain passes than the sweeping ancient glacial glens outside of Dublin. If there was any good use for Charge mode in a Prime or any PHEV that would not be a waste of gas, it would be coming down from the top of the Denver mountains or somethin.

 

On the mountain descents on my routes, this decreased speed is essential, to keep speed down to safe and legal levels. Natural rolling speeds are too high to stick on the road at the curves.

Throughout the western U.S. and Canada, we have many mountain descents of 2000 vertical feet or more. A very few of them reach 5000 vertical feet. Truckers with failed brakes either take a truck escape ramp, or die.

 

charge mode id good when approaching a mountain and you want the battery power to help the engine, or when entering a city that doesn't allow gas usage.

or if your tying to sneak home and not wake anyone up

otherwise, your just burning unnecessary fuel

 

I've gotten to 100% on a long descent.

 

"Charge" mode will only charge up to 80%. Regeneration will go up to 100%.

 

Sometimes it's still difficult for me to unprogram decades of driving where riding the brakes on steep grades is a big no no.

 

I've recharged to 100% using the regenerative braking as people have said. When going down a large grade, put the car in EV mode and use light braking as possible to recharge. You could also put the car in B mode but I've found that on long inclines, the engine might come on in that mode. Better to stay in regular mode in my opinion. Then, if you want to save the charge, put the car back into HV mode after the incline. I did this on long highway trips to save the charge for low speeds as 80+ mph burns a lot of charge inefficiently.

 

I have two trips of 22 miles, mostly hills. I travel mostly in EV and wait until all of the charge is dissipated and put the car in charge, I keep it in charge until the larger hills and when I think I have sufficient charge to make the next big downhill roll, I’ll revert back to EV. This leg is about 1000 feet. I transfer back and forth between EV and Brake in charge mode, downhill. This actually uses almost no gasoline as the car is constantly charging or in N mode to gain momentum for next charge. At the bottom of the hill I’ll have 8-10 miles of range to make the next uphill in EV.

 

This is why I call my Gen 2 Prius “The Spaceship”.
Just as spacecraft utilise the gravity wells of planets to increase their speed and reduce drastically the amount of fuel needed to accomplish those final velocities - and reach their destinations;

So also Prius Hybrids and Plug-ins can use rolling hills and crucially, momentum, to travel certain distances on minimal fuel.
During my early morning commutes, I thoroughly enjoy diving into long underpass tunnels at high mpg (and speed), and then literally coasting up the other side at 65+ mpg, before taking advantage of another long shallow dipping highway that continues to enhance cruising along at high MPGs!

Truly exhilarating when you get a clear swing through an underpass or Hill in that manner.
Of course, I occasionally encounter a half asleep dozy Dodo (think Mr Moleman) who crawls through the underpass tunnels at 35mph literally holding everyone up......and the limit is really 50mph...!!! Kind of spoils the fun crawling up the incline with mpg occasionally as low as 18mpg - depending on the circumstances.....


iPhone 6s +