Hybrids & regenerative brakes?
Discussion
RizzoTheRat said:
Surely it's the only way for a non plug in hybrid to generate electricity so they must all have it?
Nope.Honda’s system allows the ICE to charge the battery but not drive the wheels.
They also have regen braking.
Driving one is slightly surreal. Downhill they hold the exact speed set by the cruise and the battery starts charging, and you can be cruising along in EV mode and the ICE starts but just sits at a steady RPM because it is charging the battery and not driving the wheels.
ARHarh said:
My old RX400h has regen braking, it will also charge on overrun, when you just back off the throttle. Down hill will charge as will the engine when sat in traffic if the battery gets empty. Just seamlessly cuts in or out, only way to tell if the radio is on is by watching the dash.
Surely you can just hear if it is on or not?Olivergt said:
ARHarh said:
My old RX400h has regen braking, it will also charge on overrun, when you just back off the throttle. Down hill will charge as will the engine when sat in traffic if the battery gets empty. Just seamlessly cuts in or out, only way to tell if the radio is on is by watching the dash.
Surely you can just hear if it is on or not?The Toyota 1.8 version definitely does. The indication shows the battery partially charging with the engine off when you lift off the throttle, simulated to be about the same slowing down as you'd get with light engine braking in a higher gear.
If you gently press the brake pedal, it shows the battery charging faster.
It all works fairly seamlessly in normal use once you get used to it, the only drawback is that the brakes can be a bit snatchy when the friction brakes do eventually come in - which can be at pretty low speeds if you brake gently.
The other thing which is a bit weird is the engine will start up and rev almost to the limiter if you brake really hard (to provide engine braking I assume) ... but that's more of a CVT thing and only happens in emergency stops or very enthusiastic driving, which doesn't really suit that kind of car anyway.
If you gently press the brake pedal, it shows the battery charging faster.
It all works fairly seamlessly in normal use once you get used to it, the only drawback is that the brakes can be a bit snatchy when the friction brakes do eventually come in - which can be at pretty low speeds if you brake gently.
The other thing which is a bit weird is the engine will start up and rev almost to the limiter if you brake really hard (to provide engine braking I assume) ... but that's more of a CVT thing and only happens in emergency stops or very enthusiastic driving, which doesn't really suit that kind of car anyway.
Haltamer said:
Nowhere to charge a full plug in hybrid?
PHEVs - If charged - are excellent really; My friend has a 508 Hybrid that has only needed fuel every 2 months or so despite daily local trips, that combined with cabin pre conditioning etc make it superb for daily use
Yes, a PHEV would probably fit the bill most of the time, but on a longer runs it still needs plugged in to regain your full compliment of bhp. PHEVs - If charged - are excellent really; My friend has a 508 Hybrid that has only needed fuel every 2 months or so despite daily local trips, that combined with cabin pre conditioning etc make it superb for daily use
It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
ian2144 said:
Yes, a PHEV would probably fit the bill most of the time, but on a longer runs it still needs plugged in to regain your full compliment of bhp.
It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
Entirely depends on the car.It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
Not all cars use the electric motor for additional power, only to supplement the ICE. Similarly, the ICE in the Ampera is lower power than the electric motor. So with a depleted battery and no regen energy available you have less power available.
Olivergt said:
ARHarh said:
My old RX400h has regen braking, it will also charge on overrun, when you just back off the throttle. Down hill will charge as will the engine when sat in traffic if the battery gets empty. Just seamlessly cuts in or out, only way to tell if the radio is on is by watching the dash.
Surely you can just hear if it is on or not?OP: almost every hybrid has regen braking.
ian2144 said:
Yes, a PHEV would probably fit the bill most of the time, but on a longer runs it still needs plugged in to regain your full compliment of bhp.
It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
The battery in a PHEV would never go completely empty, there is always a minimum level of charge kept to provide assistance to the engine. I've got a PHEV and even without plugging in and having 10% charge on the battery, the acceleration (motor+ICE) when needed on long trips is still fairly rapid should I need to overtake anyone. It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
Yes, you need to actually drive different PHEVs before concluding anything.
All of info above is good, early days (of this modern era, not way back when cars before recent battery developments) it was more a combined belt driven motor & alternator addition, capturing some power from engine with foot off pedal & driving/idling in traffic then pushing the engine up to speed when accelerating before a lot of engine off possibility tech using an isolated electric drive came in.
Having regen then can mean it uses a driving motor independently of the ICE, or It could tap some from the ICE so you really need to check to know what you get.
An isolated engine is invariably going to be batter unless they really mucked up in R&D, or pushing something aside for marketing & increasing profit per sale, as it can be off & disconnected from drive line, not braking the car costing regeneration potential from each hill & coast down, and also wasting nothing in fuel to push oil, water & air through it if idling while your regenerating on a steep hill or coasting down to lights, but it needs to be set up that way, unless your highly attuned and act like a precision programmed robot to get the best out of it.
It's also possible to do some (New hybrid warranty voiding) DIY hackery to give an old non plug-in more battery capacity and Plug-In charging capability if you like to experiment.
I know of a few people that have the boot stocked with old car battery's with plates swapped out to a DIY lighter graphene infused plate upgrading the lead acid chemistry while renewing the plates that go bad first, refreshing an otherwise useless starting/recreation battery's whilst making them lighter using the same process a lot of Indian companies use to remanufacture part dead lead acids.
Some also using age old cheap to make Plate & stripping type DIY Zinc Bromine battery cells (Some using a gelling agent like a certain Australian company and of course the chemistry is used in massive flow battery's in certain facilities to give back up solutions)with around 60-80wh per kilo beating lead acid weight and sitting closer to lithium energy densities, they can't give a massive punch like lithium battery's but constantly push a good & steady charge into the main one to constantly regen it until they need a Plug-In charge at home to extend range a little.
So the Key thing is make sure you know what's on the car, simple engine alternator that's also going to give a little push to the running ICE, or something that can regen and move you off the lights and assist highway driving with the ice completely off as that's going to give the best mileage unless its a much larger aero dragging & heavier to move car that is.
Having regen then can mean it uses a driving motor independently of the ICE, or It could tap some from the ICE so you really need to check to know what you get.
An isolated engine is invariably going to be batter unless they really mucked up in R&D, or pushing something aside for marketing & increasing profit per sale, as it can be off & disconnected from drive line, not braking the car costing regeneration potential from each hill & coast down, and also wasting nothing in fuel to push oil, water & air through it if idling while your regenerating on a steep hill or coasting down to lights, but it needs to be set up that way, unless your highly attuned and act like a precision programmed robot to get the best out of it.
It's also possible to do some (New hybrid warranty voiding) DIY hackery to give an old non plug-in more battery capacity and Plug-In charging capability if you like to experiment.
I know of a few people that have the boot stocked with old car battery's with plates swapped out to a DIY lighter graphene infused plate upgrading the lead acid chemistry while renewing the plates that go bad first, refreshing an otherwise useless starting/recreation battery's whilst making them lighter using the same process a lot of Indian companies use to remanufacture part dead lead acids.
Some also using age old cheap to make Plate & stripping type DIY Zinc Bromine battery cells (Some using a gelling agent like a certain Australian company and of course the chemistry is used in massive flow battery's in certain facilities to give back up solutions)with around 60-80wh per kilo beating lead acid weight and sitting closer to lithium energy densities, they can't give a massive punch like lithium battery's but constantly push a good & steady charge into the main one to constantly regen it until they need a Plug-In charge at home to extend range a little.
So the Key thing is make sure you know what's on the car, simple engine alternator that's also going to give a little push to the running ICE, or something that can regen and move you off the lights and assist highway driving with the ice completely off as that's going to give the best mileage unless its a much larger aero dragging & heavier to move car that is.
Edited by NFT on Wednesday 6th July 13:23
ian2144 said:
Yes, a PHEV would probably fit the bill most of the time, but on a longer runs it still needs plugged in to regain your full compliment of bhp.
It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
Just double checked with him; ~1kWh is kept in reserve so you'll never really be down on power completely.It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
You can set a minimum power reserve in the headunit to charge the battery as you drive - Bad for MPG, but good if you're arriving at a city later in the journey and want to preserve some electrical power to maximise smoothness & efficiency there.
He makes ~60+ MPG With a starting charge at high motorway speeds; Easily attained if you plug in overnight
Haltamer said:
ian2144 said:
Yes, a PHEV would probably fit the bill most of the time, but on a longer runs it still needs plugged in to regain your full compliment of bhp.
It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
Just double checked with him; ~1kWh is kept in reserve so you'll never really be down on power completely.It's the whole plug in en route thing that would annoy me greatly...... Hence my interest in hybrid only .
I need to look into this further and maybe try a PHEV on a longer test drive .
You can set a minimum power reserve in the headunit to charge the battery as you drive - Bad for MPG, but good if you're arriving at a city later in the journey and want to preserve some electrical power to maximise smoothness & efficiency there.
He makes ~60+ MPG With a starting charge at high motorway speeds; Easily attained if you plug in overnight
RizzoTheRat said:
Surely it's the only way for a non plug in hybrid to generate electricity so they must all have it?
My thoughts too. If my Good Lady's Leaf is any guide, regen braking is pretty useless for battery charging. Even on a long downhill using regen as an 'engine brake' it notches up a couple of percentage points only. Admittedly a hybrid's battery is likely to be a lot smaller than an EV's sort. For my money a plug-in hybrid with proper on-the-road charging of the traction battery from the ICE is the only kind to have. Use the electric power when it's more efficient and IC when that's better and 'save' the charge for in-town use. Always plug in for the next trip.Gassing Station | General Gassing | Top of Page | What's New | My Stuff