How to best protect your drive battery.

[maby]

Getting back to the title of the thread. I was wondering if use of Regen setting might effect the battery life.

I tend to drive around in B0 so I do a lot of coasting up to traffic lights etc or down gradients only stepping up to B3/B5 or using the brake pedal when eventually stopping.

There are others who leave it in B5 and do one pedal driving using mainly the accelerator to moderate speed. When they lift off to slow down then Regen kicks in and they have to press the accelerator to compensate for this.

My question is whether this later style puts more stress on the battery than my coasting? - we know that it makes very little difference to overall consumption.

I only slow down in B5 when I want to, using the accelerator to moderate the speed at which I coast or slow down. I'm not clear why you think that coasting in B5 with your foot on the accelerator pedal should be any different to coasting in B0 with your foot off the accelerator. In both cases, coasting will have zero power going to and from the battery, but in B5 you also have more control if you wish to slow.

I would tend to agree in general - the B setting primarily determines what degree of regeneration is turned on when you take your feet away from the pedals. I do suspect that it can also impact on the maximum amount of regeneration that is applied. The reason is that the brake pedal is a mechanical input which both controls the regen and mechanically applies the friction brake. There is an initial motion which controls the regen level via some kind of digitizer - probably optical. As you depress the first inch or so, the friction brake is not being applied at all - beyond that point, you start to put pressure into the calipers and engage the disk brakes. On vehicles without adaptive cruise control, at least, I believe that this is a purely mechanical linkage and the point in the pedal depression at which the pads begin to engage is fixed. Therefore, if you are driving in B5 and begin to depress the pedal, it will start to increase the regen level from 5 upwards. If you are driving in B0 and begin to depress the pedal, it is starting from 0 but you still only have the same amount of pedal movement before the friction brakes begin to engage. I think that the maximum regen level that can be applied via the pedal is greater in B5 than it is in B0.

 

[cornclose]

I only slow down in B5 when I want to, using the accelerator to moderate the speed at which I coast or slow down. I'm not clear why you think that coasting in B5 with your foot on the accelerator pedal should be any different to coasting in B0 with your foot off the accelerator. In both cases, coasting will have zero power going to and from the battery, but in B5 you also have more control if you wish to slow.

But as I said in another post somewhere, it is progressively harder to 'coast' in B5 than it is in B0. On my 2019 4HS at least, the range in pedal position to give the 'neutral' point (no power applied to drive motors and no regen from drive motors) in B5 is not easy to find. Much easier in B0 - just lift off..

Whenever in regen, yes you are recovering energy but you are wasting potential travel distance you could have attained by coasting further in B0. From my experience so far it is more efficient to drive in B0 performing less regen than it is in B5 where the car will regen more readily if you don't get the sweet spot where it will 'coast'. In short;

1. Most efficient is to never regen, covering most distance by coasting.
2. Least efficient is to be applying mechanical braking of pads on to the discs.

Any amount of regen falls between the two since you cannot recover the energy from regen that was used to gain the kinetic energy (i.e. move the vehicle) in the first place.

 

[maby]

I only slow down in B5 when I want to, using the accelerator to moderate the speed at which I coast or slow down. I'm not clear why you think that coasting in B5 with your foot on the accelerator pedal should be any different to coasting in B0 with your foot off the accelerator. In both cases, coasting will have zero power going to and from the battery, but in B5 you also have more control if you wish to slow.

But as I said in another post somewhere, it is progressively harder to 'coast' in B5 than it is in B0. On my 2019 4HS at least, the range in pedal position to give the 'neutral' point (no power applied to drive motors and no regen from drive motors) in B5 is not easy to find. Much easier in B0 - just lift off..

Whenever in regen, yes you are recovering energy but you are wasting potential travel distance you could have attained by coasting further in B0. From my experience so far it is more efficient to drive in B0 performing less regen than it is in B5 where the car will regen more readily if you don't get the sweet spot where it will 'coast'. In short;

1. Most efficient is to never regen, covering most distance by coasting.
2. Least efficient is to be applying mechanical braking of pads on to the discs.

Any amount of regen falls between the two since you cannot recover the energy from regen that was used to gain the kinetic energy (i.e. move the vehicle) in the first place.

I drive on cruise control most of the time (not much urban driving) - so the car is in control and sets the throttle as it sees best. It is worth noting that (at least for cars that don't have adaptive cruise control), the B setting determines the maximum amount of deceleration that will ever be applied in cruise control. I have quite a long down-hill stretch on the approach to our house which I normally take on cruise control with the speed set to 40mph. The first time I did it, I had it set to "D" - effectively "B2" and the car ran away - I nearly got a ticket passing the speed camera half way down. I now make sure that it is set to B5 at the top and it stays at 40 all the way down.

 

[cornclose]

I drive on cruise control most of the time (not much urban driving) - so the car is in control and sets the throttle as it sees best. It is worth noting that (at least for cars that don't have adaptive cruise control), the B setting determines the maximum amount of deceleration that will ever be applied in cruise control. I have quite a long down-hill stretch on the approach to our house which I normally take on cruise control with the speed set to 40mph. The first time I did it, I had it set to "D" - effectively "B2" and the car ran away - I nearly got a ticket passing the speed camera half way down. I now make sure that it is set to B5 at the top and it stays at 40 all the way down.

What model year ?

On my 2019 4HS, if you set cruise (adaptive cruise at any rate.. not even sure there is a 'normal' cruise on mine as I rarely use cruise full stop, a human is better at managing energy and speed than the car is (well at least this human is.. :lol: )), the car automatically goes to 'D' (i.e. B2). If you try to change the B mode whilst the adaptive cruise is active, it cancels the cruise function.

 

[elm70]

I bet every PHEV can't use B0 and B1 once cruise control is activated.

In my 2013 PHEV, once cruise control is active, I can only select from B2 to B5

Every time I disable the cruise control, I need to be quick on move to B0.

Back to B0 vs B5 , in relation to battery degradation.

I believe B5 does stress further the battery for 2 reason:
- Per Mitsubishi design, using B5 vs B0, does not only impact the automatic deceleration and regen, but as well with B5 the max regen power is around 50% more then not in B0 ... regen power in my view is too high for the size of the battery .. people experience above 40kw regen in B5, with a 12kwh battey .. my knowledge of Lithium battery was always telling me that ideally battery should be charged at 1C (or even slower) ... so 12kwh battery should be charged only at a max 12kw or less
- Using B5 vs B0 on driving style... using B5 it implies that driver need to have a a ultra precise and steady foot .. else traveling at "constant" speed implies "continuous" change between acceleration and deceleration with using power and regen ... at least this was my 1st analysis of EVbatMon logs on my first drive in B5 mode ... using B0 allows to reach the wanted speed .. and then glide from that speed, having a better preservation of the kinetic energy ... clearly ... this also depend on driving style and driving condition .. on the stop and go traffic in a city center, yes B5 normally does not have much side effect ... still ... ideally is better to let the car glide ini B0, and then switch to B5 when is needed to slow down (better for the driving efficiency, but not good for the battery for the problem in the first point) .. in short B5 can cause a lot of unwanted regen, which lead to stress further the battery

Anyhow ... more then B0 vs B5 ... the protection of the battery is more in the charge management ... the worst possible thing is to charge the car immediately after usage , and then let it sit fully charged for many hours or days.

 

[maby]

I drive on cruise control most of the time (not much urban driving) - so the car is in control and sets the throttle as it sees best. It is worth noting that (at least for cars that don't have adaptive cruise control), the B setting determines the maximum amount of deceleration that will ever be applied in cruise control. I have quite a long down-hill stretch on the approach to our house which I normally take on cruise control with the speed set to 40mph. The first time I did it, I had it set to "D" - effectively "B2" and the car ran away - I nearly got a ticket passing the speed camera half way down. I now make sure that it is set to B5 at the top and it stays at 40 all the way down.

What model year ?

On my 2019 4HS, if you set cruise (adaptive cruise at any rate.. not even sure there is a 'normal' cruise on mine as I rarely use cruise full stop, a human is better at managing energy and speed than the car is (well at least this human is.. :lol: )), the car automatically goes to 'D' (i.e. B2). If you try to change the B mode whilst the adaptive cruise is active, it cancels the cruise function.

As elm70 explains, the PHEV will not permit B settings below B2 while in cruise control - because it would not have the ability to decelerate adequately. It will permit settings between B3 and B5 - and the selected setting dictates the maximum deceleration that it can apply to slow the car while under cruise control. This may be different for cars with adaptive cruise control and collision mitigation - even B5 will not apply a high level of deceleration and I assume that collision mitigation must be able to apply the friction brakes...

 

[cornclose]

As elm70 explains, the PHEV will not permit B settings below B2 while in cruise control - because it would not have the ability to decelerate adequately. It will permit settings between B3 and B5 - and the selected setting dictates the maximum deceleration that it can apply to slow the car while under cruise control. This may be different for cars with adaptive cruise control and collision mitigation - even B5 will not apply a high level of deceleration and I assume that collision mitigation must be able to apply the friction brakes...

I will try again next time I use cruise. I can't recall when in cruise whether I attempted to select B1 or B0 or whether it was a higher B3+.

 

[ThudnBlundr]

I must admit that I don't find it a problem maintaining speed in B5. There are very few times that I wish to maintain an exactly constant speed except on the open road, when I tend to use ACC. I do use the speed limiter around town, but that has a different effect to coasting.

In B0, the regen is obviously zero when you take your foot off the accelerator, and only a few kW when you brake. In B5 it can be over 30kW when the accelerator is released, and well over 40kW when braking. This would suggest that the PHEV doesn't have a simple mechanical linkage for the brakes, and has some algorithm for how much brake to use. I don't know about the PHEV, but I do know that our Zoe constantly calculates the max regen it can generate based on factors such as SOC, temperature, etc. It then calculates how much brake pressure to apply based on how hard you've pressed the brake pedal. If it doesn't need to use the brakes at all, it will "brake" solely on regen till it's going slowly enough that it needs to apply the brakes. It's very clever, as the driver knows nothing about it - the pedal feels normal till it switches to full friction brakes at around 5mph, when there's often a slight hesitation. Apart from first thing in the morning with a full battery when regen is virtually zero, you can avoid using the friction brakes at all if you're gentle. People have had the pads last well over 40k miles. At the last service at 25k, ours were less than 50% worn.

I can only talk about ACC on my 2015 car, but it certainly does vary the 'B' setting when braking. It will regen far more than the B2 setting will allow when slowing quickly, based on the regen levels shown on the dash and in the PSideP display. It just won't let you alter them, as it would be meaningless if the car varies it automatically. It does default back to 'D' when you cancel, though :roll:

 

[elm70]

As elm70 explains, the PHEV will not permit B settings below B2 while in cruise control - because it would not have the ability to decelerate adequately. It will permit settings between B3 and B5 - and the selected setting dictates the maximum deceleration that it can apply to slow the car while under cruise control. This may be different for cars with adaptive cruise control and collision mitigation - even B5 will not apply a high level of deceleration and I assume that collision mitigation must be able to apply the friction brakes...

I will try again next time I use cruise. I can't recall when in cruise whether I attempted to select B1 or B0 or whether it was a higher B3+.

My PHEV does beep if I try to go into B1 while cruise control is active

But tpchnage from B2 to B5 it is left allowed

My PHEV does not have adaptive cruise control, so no idea if having adaptive cruise control make any difference on the B settings.
I would expect that for adaptive cruise control, not only regen should be used for slow down, but also the braking pads too.
On a normal cruise control I believe it is less critical to be able to slow down quickly like I believe it is needed with adaptive cruise control for prevent to crash into a car which it might use full brake at any point

 

[cornclose]

I must admit that I don't find it a problem maintaining speed in B5.

Neither do I - but it's not about maintaining the speed but about maintaining the car in that band where it is neither using battery power or regenerating. That is what is 'akward' (rather than difficult) in B5 (even at the same speed), and very easy indeed in B0.

Your post however reads as though you set the car in B5 and don't deviate from that, whereas I (and others it seems) appear to cycle up and down the B levels as they see fit and as road conditions allow, which is what the function was designed for in my view.

I too rarely touch the brake pedal, so it's not something unique to some electric vehicles and not others. Of course, you have to brake using the pedal if it is needed, but 90% of the time I increase the B level from B0 which is where I want to be most of the time, progressively to B5 to slow down - all without touching the brake pedal. Of course I aim to stay in B0 as long as possible as, contrary to seemingly popular belief, any use of regen is wasting energy you've already used to get you moving! It just wastes less than using the brake pads/discs to slow down.

 

[maby]

The only time I touch the paddles is when descending a steep hill! Otherwise, the car is in "D" or "P" all the time. The fuel saving seems to be minimal and the potential to damage the battery even faster than it is damaging itself is too great to justify using regen.

 

[cornclose]

The only time I touch the paddles is when descending a steep hill! Otherwise, the car is in "D" or "P" all the time. The fuel saving seems to be minimal and the potential to damage the battery even faster than it is damaging itself is too great to justify using regen.

If you take that to it's logical conclusion then you should really be using B0 all the time!

 

[maby]

The only time I touch the paddles is when descending a steep hill! Otherwise, the car is in "D" or "P" all the time. The fuel saving seems to be minimal and the potential to damage the battery even faster than it is damaging itself is too great to justify using regen.

If you take that to it's logical conclusion then you should really be using B0 all the time!

I drive in Cruise Control almost all the time and that does not permit B0.....

 

[cornclose]

We can all drive how we want to at the end of the day, within the limitations set by the manufacturer.

I'm just pointing out that if your main concerns are not shortening the life of/damaging the battery then only using B5 when going down a steep hill is probably one of the most damaging times of all, and use of B0 for coasting does indeed indirectly save fuel/electricity as it maximises EV range whilst minimising or eliminating regen (smaller amounts of energy used to move the car and then less waste slowing the car down when in regen), thus 'protecting' battery longevity.

 

[greendwarf]

Getting back to the title of the thread. I was wondering if use of Regen setting might effect the battery life.

I tend to drive around in B0 so I do a lot of coasting up to traffic lights etc or down gradients only stepping up to B3/B5 or using the brake pedal when eventually stopping.

There are others who leave it in B5 and do one pedal driving using mainly the accelerator to moderate speed. When they lift off to slow down then Regen kicks in and they have to press the accelerator to compensate for this.

My question is whether this later style puts more stress on the battery than my coasting? - we know that it makes very little difference to overall consumption.

Hello Mr greendwarf Sir,

I think it is something we all can agree on is the less we use our battery the better so the more we coast up to the lights the better IMO.

Any snow on the Alps over there? Wee bit warm here lately.

Chilly this morning Trex but dry as a bone - not even a frost (as Maby has pointed out) unlike the real Alps - you have my sympathies

 

[Trex]

I don't have the equipment to measure the health of the battery pack,

We really have to get a OBD-II scanner to look at your battery other wise we are guessing here IMO and even then without a recalibration of the BMU it is not perfect . But it would be a good start I think. If you like I could send you mine over there but that would require giving an Aussie who lives in the outback your address. :lol:

I still maintain that Mitsubishi should have recognised that many PHEVs were going to be used for long trips, well beyond the EV range, from time to time and had included a mode that manages battery charge levels to reduce battery degradation and ensure that the car always has a decent reserve of electrical drive for hill climbing, motorway acceleration etc. We implement this ourselves by juggling the Save and Charge buttons, but that simply should not be necessary.

I think there could be number of reasons why Mitsubishi have not done what you want and you have said this often enough. Its not as if its hard to press a button every now and again. Boy, you would have hated being a pilot IMHO. :roll:

I do recognise that the Prius uses different battery technology to the Outlander, but that does not excuse Mitsubishi - if they can't get a decent life expectancy out of the battery pack, they should not have released the vehicle! I probably should have bought a Lexus RX-4nnh but the UK government had removed all the incentives for that by the time we gave up the Prius.

Ok, back to nonconstructive bashing of Mitsubishi from what I can see. Do you know the degradation on the battery on your old Prius BTW?

 

[Trex]

They would be wise to implement a low-cost battery refurbishment/replacement program.

Yeah, or other wise someone else will IMO.

 

[Trex]

Getting back to the title of the thread. I was wondering if use of Regen setting might effect the battery life.

I tend to drive around in B0 so I do a lot of coasting up to traffic lights etc or down gradients only stepping up to B3/B5 or using the brake pedal when eventually stopping.

There are others who leave it in B5 and do one pedal driving using mainly the accelerator to moderate speed. When they lift off to slow down then Regen kicks in and they have to press the accelerator to compensate for this.

My question is whether this later style puts more stress on the battery than my coasting? - we know that it makes very little difference to overall consumption.

Hello Mr greendwarf Sir,

I think it is something we all can agree on is the less we use our battery the better so the more we coast up to the lights the better IMO.

Any snow on the Alps over there? Wee bit warm here lately.

Chilly this morning Trex but dry as a bone - not even a frost (as Maby has pointed out) unlike the real Alps - you have my sympathies

No worries Mr greendwarf Sir. I will survive.

 

[Trex]

Ok finally found this:

Ok just did a quick test this morning. It was on the same test section I did this test.

Hi folks,

This will be the last test I will do for awhile. I hope it helps everyone.

I picked the flattest area around here ( and it is very flat across the river valley here) on the dual lane freeway (in each direction) that runs past our small city. It is made up of approx. 12kms of 100kph zone and 10km of 110kph zone. I picked that stretch for its easy turn around at each end as well as being flat.

So the test consisted of driving in one direction then the other followed by a quick turnaround at each end. Traffic was light. I sat on 105kph . I used cruise control the whole time except at each end when I was turning around.

Now this is the same as I did the other night but more scientifically ie I ran both directions fully before taking measurements to allow for any wind or elevation changes. I have not, I repeat not done that before.

Here are the results.

Press save button straight at start with full battery. 15 bars showing (out 16 ) on MMCS when finished test. 7.8L/100k Petrol motor never stopped. B5 15kw

Press Save at 13 bars. 14 bars showing (out 16 ) on MMCS when finished test. 7.8L/100k Petrol motor never stopped. B5 25kw

Press Save at 11 bars. 12 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times B5 37kw

Press Save at 8 bars. 9 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 7 bars. 8 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 6 bars. 7 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 4 bars. 5 bars showing (out 16 ) on MMCS when finished test. 7.2L/100k Petrol motor stopped like a proper hybrid. B5 37kw

At 1 bars (normal mode). 1 bars showing (out 16 ) on MMCS when finished test. 7.2L/100k Petrol motor stopped like a proper hybrid. B5 37kw

Note No AC or heater on.

Note The B5 amounts are Regen that I could get at the end of the runs with the paddles set to B5 when turning around.

Note Where I said the petrol motor never stopped it only stopped at each end of the run where I turned around.

Note Where the Petrol motor stopped I read it at the same point of the hybrid cycle.

Regards Trex.

Well now we have EVBatmon (Thanks guys) we have some more tools I wish I had when I did that previous test.

Now anko may have shown some graph that shows this somewhere around here and if he does this backs that up.

So back out on the highway I went and got these results.

15 bars (out of 16) showing on the MMCS battery gauge Generator Power 6.1 kW approx. on EVBatmon. Pressed save right at the start for this one.
14 bars (out of 16) showing on the MMCS battery gauge Generator Power 7.7 kW approx. on EVBatmon.
13 bars (out of 16) showing on the MMCS battery gauge Generator Power 8.1 kW approx. on EVBatmon.
12 bars (out of 16) showing on the MMCS battery gauge Generator Power 9.6 kW approx. on EVBatmon.
10 bars (out of 16) showing on the MMCS battery gauge Generator Power 10.8 kW approx. on EVBatmon.
8 bars (out of 16) showing on the MMCS battery gauge Generator Power 14.0 kW approx. on EVBatmon.
6 bars (out of 16) showing on the MMCS battery gauge Generator Power 16.9 kW approx. on EVBatmon.

Now I stopped there as my wife wanted the car soon and I wanted to leave her some battery showing her I am such a nice guy.

Anyhow, I think, it shows that the car is more efficient with a lower battery SOC just like my previous test.

Regards Trex.

ps added 15 out 16 bars ie pressed save at the start of turning on the PHEV.

Will tidy this up later. Got to go.