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Hi

the figures I am getting about how much energy I consumed does not seem to match up with the percentage readings I am getting.
My 24kWh Leaf is still on its 12 bars (last checked with LeafSpy a month ago on about 90%). Even if it has dropped since it should be above 85% as everything below would mean a lost bar. So I should have at least 20.4kWh of battery capacity left.

Yesterday I did a round trip to the office which according to the Nissan EV app was 77.5 miles. When I got to the office the battery was down to 50% (down from 100%). I charged up back to 100% and PodPoint told me I've charged 8kWh. When I got back home my charge was at 54%. The Nissan Leaf app said I consumed 16.8kWh. Given that I used 96% (50+46) of my battery which equates to 16.8kWh my total capacity should be at 17.5kWh at the moment but that would only be about 73% of the original capacity of 24kWh. So I should have lost a couple of bars already?

The figures don't quite add up. Is the percentage shown based on the 'usable' capacity of the battery (so e.g. out of the 24kWh only e.g. 22kWh are usable before the Leaf would go into Turtle mode?)
 

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Keep in mind that the 100% in display is only 90% of usable energy while you won't ever be able to run the batteries below the "protection zone"
This prevents the batteries to be damaged.
The 8kw charge is what the station has given you but doesn't account to other use such as heating etc.
to be mathematically exact you would have to calculate even energy losses in the cable and car circuit.
I don't think Nissan waned to be that accurate when they produced the display otherwise you would have a 2 decimal digits display.
 

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The podpoint app doesn't account for charging loss.
The 24kWh is total capacity. Actual usable capacity is around 22kWh, 85% of that is only 18.7kWh.

Also, unless you've ran 100% down to near 0%, working out percentage used by adding a certain section of percentage will not be accurate. The Leaf percentage reading is known to be inaccurate, eg top half may be actually top 45%.

I've given up trying to calculate such numbers...... it also seems to vary by ambient temperature.
 

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Numbers are just numbers. If the car gets you to where you want to be and back to where you came from, then it must be working.

Every time you move electrons from one place to another, some always escape (personally I think they run away to create lightning strikes over my house). The systems that tell us how many electrons were moved don't admit to some escaping and only guess how many were moved in the first place. So we are left with "best guess" numbers given by electronics that guess the battery level and guess the battery health. They compare it to a guess of how far you can go on the other guess's based on a guess of how many miles you went before on the same level of guess. It's all guesswork but gives you a general idea of where you're at and how far you can go.

Charge, drive and enjoy. :)
 

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Numbers are just numbers. If the car gets you to where you want to be and back to where you came from, then it must be working.

Every time you move electrons from one place to another, some always escape (personally I think they run away to create lightning strikes over my house). The systems that tell us how many electrons were moved don't admit to some escaping and only guess how many were moved in the first place. So we are left with "best guess" numbers given by electronics that guess the battery level and guess the battery health. They compare it to a guess of how far you can go on the other guess's based on a guess of how many miles you went before on the same level of guess. It's all guesswork but gives you a general idea of where you're at and how far you can go.

Charge, drive and enjoy. :)
In mine they vescape to create a static charge build up that zaps me everytime I exit the car

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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Discussion Starter #7
Okay good to know that the percentage is actually the 'usable' capacity. I always try to avoid going close to 10% as I thought the Leaf wouldn't let me use the last 10% and would go into Turtle mode.
Now the question is would I manage the round trip of 78 miles (using 16.8kWh as reported by the Nissan EV app) without charging up at work? There are 4 charging bays but they tend to get used up pretty quickly so there might be the change that I won't be able to charge up. Would I make it back? I guess it depends on the weather etc but can I use let say 96% of the battery without going into Turtle mode? I guess it is cutting it a little bit too fine.
 

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Okay good to know that the percentage is actually the 'usable' capacity. I always try to avoid going close to 10% as I thought the Leaf wouldn't let me use the last 10% and would go into Turtle mode.
Now the question is would I manage the round trip of 78 miles (using 16.8kWh as reported by the Nissan EV app) without charging up at work? There are 4 charging bays but they tend to get used up pretty quickly so there might be the change that I won't be able to charge up. Would I make it back? I guess it depends on the weather etc but can I use let say 96% of the battery without going into Turtle mode? I guess it is cutting it a little bit too fine.
One thing that is worth looking for is a weak cell, what you are describing is similar to what I found when my battery had a weak cell, I found that Leaf Spy reported a significantly higher % soc than that displayed on the dash, initially they were very close but as the dash display got down to 50% soc the deviation started to increase.
when the display went down to -- Leafspy was still saying 25%.
Since the cell has been replaced the display and LeafSpy are much closer all the way down.
I know there is a bit top and bottom that are not available hencw when display is at 100% lspy will show 97% ish that 3% is the BMS protection margin it has a similar margin at the lower end.
I have also noticed since the cell replacement it now takes a lot longer to charge !
 

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In winter, I sometimes get nerves with my 56 miles commute. If you are using 97% now, you don't have a chance in winter, rain or during windy days.

I'd set it to charge to 80% and plug in at both ends of the journey.
 

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FWIW, my own experience of the % remaining display for my Leaf24 is that it also became unreliable below as my battery pack approached 85% of original capacity; I would observe quite fast and unpredictable % drop below ~40% and especially between 20% to '---'. When the first battery bar eventually disappeared, the % reading suddenly became reliable again, as if the BMS system had adapted or reset itself, without any change in use or driving habits, and so far it continues to behave itself. YMMV.

Will have to borrow LeafSpy again to see how battery is doing, I suspect I'm getting close to the 11th bar going since full charge is completing in about 3.5 hours (at 6.6kW) :(
 

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In winter, I sometimes get nerves with my 56 miles commute. If you are using 97% now, you don't have a chance in winter, rain or during windy days.

I'd set it to charge to 80% and plug in at both ends of the journey.
Some spirited driving at the end of a trip can warm the battery and help maintain range. As can a rapid charge. The worst case is not using the car for a few days in winter, stone cold battery- then attempting a commute! I used to have ~65 miles range in my 5 year old Leaf 24. Sometimes you simply have to slow down.
 
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