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Discussion Starter #1
A quick little observation from leafdd - gen. 1

No figures before then. Note I tended to charge to 80% 240V 10A until around May 2013, then switched to 100% 240V 16A charge

Oct 2013 Hx=79.62 C=59.30
Nov 2013 Hx=80.46, C=59.64
Mar 2013 (b4 trip) Hx=80.85, C=59.80
Mar 2014 (after trip) Hx=87.10, C=61.77 (ambient 12C)

Additionally a charge to around 255 GID is now around 260 GID.

So *according to these figures* my battery has been getting slightly better, and long trips (825 miles, quite a few RCs in decent days) are good for the battery.

I'm aware temp can be a strong factor and sadly I don't have ambients for the older figures, but I've taken many more readings than those above and there seems a gradual shift rather than quick changes based on weather

Of course there's no real guarantee as to what these figures mean.... so all of this could mean nothing in terms of the battery itself. but still ...

Ummm....
 

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Checked this morning immediately after charge completed - ambient just over 13C, same Hx/C figures close enough. Yet GIDS are 264. Some of this will be surface charge so I expect a few to get dropped, but it does beg a question as to the relationship between these figures.

It reminded me of another observation during last weeks trip.. I watched a fair bit of charging, and noticed that though the power input was fairly steady, and gradually increasing as charge level increased (leafdd flickers, but if you average over a second or two it's gradual), the GID increase was not linear. I noticed GIDS being skipped, or moving quickly like 222, 224, then perhaps a slow period (over 10s of seconds) then a faster period. Yet the % charge level shown on leafdd was much smoother, and as expected per the charge rate.

Not really important, perhaps just a reminder that one can only take these figures as hints as no-one outside nissan really knows what they mean. The most important use for me is to get a better handle on consumption and finer accuracy once LBW is hit, and especially VLBW where just reading "---" isn't especially useful!
 

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Something that might possibly explain some of the jumpy figures is that the LeafDD/LeafSpy is sampling the CANBus. IIRC the CANBus on the Leaf is fast, very fast. The LeafDD/LeafSpy OBD2 links sample at quite a slow rate compared to the real rate of the bus so it is quite possible that not all the messages on the bus are "seen". This could result in a jumpy display as some messages are missed.

Overall this matters not because we see enough of them for our purposes.

I think we are right to be cautious of these figures and as you say, they are unofficial and so they are nothing more than educated guesses but for me they are useful enough for my purposes which are pretty much the same as yours :)
 

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I've also noticed battery 'healing'..

I drive the same route almost every day in the week and either 1/2 discharge or fully discharge my battery. Home to work (carefully) is full to LBW + 2-3 miles. Through the winter I was plotting Hx on a spreadsheet against miles and noticed a cycle of Hx increasing and decreasing, then increasing again.

G when full has been as low as 252 and as high as 264. (Its interesting our figures are similar, and probably a good sign).

Temperature does play a part, and it will be interesting to see what I can peak at as the weather warms up. I'm back up to 262 over the last few days.

Taking Pauls point - I was also thinking of charting the kWh to charge at 'the plug' (i'm already recording this) against the kWh LeafSpy states. Exactly accurate or not, if consistent the provide a useful view of status.
 

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That is interesting... I had 264 a few weeks ago and yesterday I had 251... almost identical to your hi and low.

I too am hoping it cycles back up because if it doesn't then we have lost 13G in the past few weeks :eek:
 

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My leaf will be 3 years old in august, I have charged to 100% every night since new! last svc said pack was as good as new,

I worked on the thought that I only planned to have the car three years and the packs under warranty so why not :)
 

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Where do you live Jon? Perhaps I or someone else could drop by and plug in to see what the LeafSpy/LeafDD says?

:)
 

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I'm about 45 miles away in Corby, wouldn't mind popping over to plug in my LeafDD :)
 
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