Nick's Leaf Recommendations (2013 SV)

[nickandre]

You can read my full articulation and reasoning here, but I would like to make the following recommendations to Nissan after driving the 2013 SV leaf for about 4 months:

1. Provide settings that allow the user to tweak the B and D modes. Specifically, I would like to be able to adjust the D mode such that it applies no regenerative braking without the brake pedal and the B mode such that it applies full regen all the way down to a stop rather than inexplicably backing off starting at 45 MPH and applying power when the car reaches 8 MPH. I would also like to disable the creep because it's useless (and I would guess maintaining the creep is why the B mode is bastardized to fail to apply full regen at speeds below 45 MPH).
2. Adjust the regenerative braking such that the car preferentially applies maximum regen before engaging the mechanical brakes to increase efficiency and reduce wear and tear. The current behavior requires that I whale on the brake pedal to get full regen at slow speeds (but it is apparent that the car can apply full regen at very low speeds).
3. Provide a capacity indication in kWH rather than entirely arbitrary bar or percent system. Why even bother to give efficiency in miles/kWH if you don't provide kWH?
4. Please don't use the "fog of war" technique of leaving drivers in the dark below 10% SOC. Both the guess-o-meter and percent capacity meter shut off at 10% and 5% charge remaining, which is rather annoying, requiring me to fire up the LeafSpy app to tell how much power I have left.
5. Allow me to use FLAC files on the entertainment system. Allow the spare SD card slot to be used to hold media.
6. The current behavior requires that you shut your car off before charging. First, the door to the charge port cannot be opened with the vehicle on. Second, the car will not charge if the charger is plugged in while the vehicle is on. Instead, the charge port door should be opened regardless of the state of the vehicle and the action of plugging in a charger should disable the drivetrain. Currently, I must shut off the car, open and plug in, and then turn the car back on to enter the "charge and stay warm inside" mode.
7. Why is there a jungle noise that can't be shut off every time the car is turned on? Who thought this was a good idea?
8. The car should provide a more accurate statement of how healthy the battery pack is. When I received my car it was within a few weeks of losing a capacity bar after its two year lease down in Georgia but the car gave no way to distinguish between its pack and a brand new one. It's also apparent that the relevant information exists in the car's computer system because the LeafSpy app provides a State-of-Health indicator for the pack in %.
9. Lose the "world's most useless" tree meter and put something useful like efficiency in miles/kWH and kWH remaining in that location.

 

[Levenkay]

1. Whether the LEAF will behave this way for newer-techonology batteries is unclear, but the experience of first-model LEAF drivers seems to be that there's a massive curtailment of regenerative braking as the batteries age or degrade. If they're still doing that, all your proposed fiddly tweaks with regeneration policy would only apply while the car is young anyway.

7. If you hunt through the Menu->{Enter/Next} system of awkward menus governing the use of the driver's center-console readout area, you should find a menu for "Effects" (I think it's called), where you can select among three different annoying startup audio annunciations or "None". You seem to be a candidate for the "None" selection.

 

[nickandre]

Interesting. I had assumed that the internal rectifier was the bottleneck of regen, though I find it surprising that the car can regen at 30 kW but only charge at 6.6 kW

I've seen curtailing of the regen at cold temperatures and higher SoCs, and I'm not sure how the pack resistance and cell age etc. affects this. Interesting point. What I'm talking about is specifically the speed-related curtailing, which shouldn't have anything to do with the pack, especially since it's quite obvious that full regen is possible because it will do that when the brake pedal is hammered.

It's the annoying compromise of "use a bit of regen in D mode to make the car feel like it has an automatic transmission" rather than accepting that this is not an ICE vehicle.

 

[powersurge]

Good observations....

 

[finman100]

Knowing the kWh has been crucial for my Leaf experience. Sadly, that had to come from 3rd party vendors! (leafstat as well as leafspy, both via wifi sent to my iphone). Really, Nissan? BASIC fuel left in the tank is a bar graph and % number? What if gassers had this stupid omission? kWh equates to gallons. No one in their right mind would drive an ICE with no fuel gauge! Just plain silly to the point of being maddeningly dumb.

On the other hand, I love my Leaf!

GOM (guess-o-meter) be damned, I got LeafSpy to tell me the truth.

 

[powersurge]

Yes, goodbye tree
Yes, display Kilowatts (which is the same as % of charge).
No, you should not be able to plug in if the car is on.. safety, and also so you do not drive away with the plug connected.

My additions - 1) have a weather proof charging port so that ice and snow does not clog things.
2) make the 100% charge be what is still considered safe for the battery. I am tired of so many that have to worry of only charging to 80% to no hurt the battery.

 

[Jefe]

Really, Nissan? BASIC fuel left in the tank is a bar graph and % number? What if gassers had this stupid omission? kWh equates to gallons. No one in their right mind would drive an ICE with no fuel gauge! .

Uhm. The gauge that is there shows percentage, which is almost a direct correlation to what gassers get. No car that I am aware of tells you exactly how many gallons of gas you have left in your car. It gives you a meter with lines and a pointer from which you deduce how much fuel you have based on segments. In my Prius, we had "pips" and they were wildly inaccurate due to the fact that the fuel tank had an expandable bladder.

My wife's Highlander has its own "GOM" so to speak, that tells you how many miles you have left based on your tank. It is just as inaccurate as the Leaf's.

 

[nickandre]

Really, Nissan? BASIC fuel left in the tank is a bar graph and % number? What if gassers had this stupid omission? kWh equates to gallons. No one in their right mind would drive an ICE with no fuel gauge! .

Uhm. The gauge that is there shows percentage, which is almost a direct correlation to what gassers get. No car that I am aware of tells you exactly how many gallons of gas you have left in your car. It gives you a meter with lines and a pointer from which you deduce how much fuel you have based on segments. In my Prius, we had "pips" and they were wildly inaccurate due to the fact that the fuel tank had an expandable bladder.

My wife's Highlander has its own "GOM" so to speak, that tells you how many miles you have left based on your tank. It is just as inaccurate as the Leaf's.

The problem with % is that right now my 100% on my leaf means 80% on a new vehicle because of battery deterioration, so it doesn't at all equate to range. The guess-o-meter is kWh multiplied by some undisclosed and changing efficiency value generated by witchcraft.

Just simply stating 18.9 kWh remaining would solve ALL these problems. Gas cars use stupid estimation gauges because the gas is sloshing around in the tank. Electrons don't slosh nearly as much.

 

[Levenkay]

Just simply stating 18.9 kWh remaining would solve ALL these problems. Gas cars use stupid estimation gauges because the gas is sloshing around in the tank. Electrons don't slosh nearly as much.

Estimating the useful energy content of the battery from its measured terminal characteristics isn't a completely trivial problem, either, though. It's a little like trying to calculate how much government you've got by adding up the taxes you've paid: sometimes, quite a large flow can go in without appearing to do much...

 

[GetOffYourGas]

Estimating the useful energy content of the battery from its measured terminal characteristics isn't a completely trivial problem, either, though. It's a little like trying to calculate how much government you've got by adding up the taxes you've paid: sometimes, quite a large flow can go in without appearing to do much...

+1 Nice analogy!

 

[Jefe]

The problem with % is that right now my 100% on my leaf means 80% on a new vehicle because of battery deterioration, so it doesn't at all equate to range. The guess-o-meter is kWh multiplied by some undisclosed and changing efficiency value generated by witchcraft.

Just simply stating 18.9 kWh remaining would solve ALL these problems. Gas cars use stupid estimation gauges because the gas is sloshing around in the tank. Electrons don't slosh nearly as much.

Not denying that. But the assertion that gas cars somehow have it better just isn't true.

 

[arnis]

Some information:

Leaf can regen up to 50kW but only with the help of brake pedal.
30kW is more reasonable because drivers should not have more deceleration
with normal driving. It also is a little bit better for battery (compared to 50kW
on every intersection and traffic light).

I believe Nissan intentionally dashed the range when it gets very low.
It turns out discharge to less than 3.5V per cell does more harm than
charging above 4V (80% charge). I think they tried to force users charge above
80% if users get down to VLBW.

Also it might be that decelerating to a stop using regen has negative effect on range.
Kinetic Energy = mass multiplied by speed squared. At 5mph there is nothing really left.
But accelerating form 0 to 5mph takes a lot of juice if pushing more than a third.
So for better range it is better to do the way they did. For more comfort it is better to do
they way we all want it to happen VW E-golf has exactly what we need.

Creep on the other hand should be an option. The way efficient acceleration should be
managed is by heavily limiting acceleration from standstill in ECO. Anything less than
2/3 of ECO pedal is more like 5-20kW power, not 30-40kW. But Nissan tried to hint that
using trees - nobody cares about those.