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Discussion Starter #1
I had some fun this afternoon. When I returned from my 200 mile trip to Highbridge today I was pretty low on power when I arrived home so I popped into tell my other half that I was going around the block a few times to see how low I could go before it went to Turtle mode. My wife put the kettle on and made tea assuming I'd only be 5 or 10 mins. What happened resulted in me being delayed for my tea!

I went twice around a circuit watching LeafSpy as I went trying to guage if I could get around another loop. What I was trying to do it see at what percentage SOC I could go down to. The idea was not to actually get to Turtle but if I could get close then I would have a bottom SOC that I was comfortable going down to.

The thing is that I totally misjudged it and thought I had power enough for another 1 mile loop... I didn't! I went to Turtle about 400yds from my house and the car stopped about 300yds from the house. It only went 100yds in Turtle mode. That was less than I expected but nonetheless... I still misjudged it!

As our other car is an Ampera which cannot tow (nowhere to safely attach a tow rope without damage) I had to call a mate who came and towed me the 300yds home with his Land Rover.

No harm done except that my tea went cold!

The annoying thing is that in all the excitement I forgot to look at how low it went at Turtle so I will have to do it again at some point. DOH!

I know I can drive safely down to 7% and it was probably a bit lower than that at Turtle. It had just 2 GIDS remaining when it stopped completely.

On the short tow back I was in N so probably no harm done and I did not have power steering but brakes were fine.

Believe it or not but this is the first time in not far off 3 years of owning the Leaf that I have gone into Turtle mode. If you can do it safely knowing you can be recovered back home then I do recommend you do it once to experience it. It will help preventing any anxiety when you get that low battery warning!
 

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have only once got to zero on the leaf, the turtle light came on as I pulled into the fast charger at maple cross so never got to see how far it went on turtle but good to know its not far :)
 

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On my first longish journey ( 68 miles round trip ) I almost died. We made it back home but the remaining mileage ended up displaying -- not zero but a couple of -- symbols.

I thought any moment now it's going to go into turtle mode but luckily I pulled onto the drive at home and was able to charge.

I did initially think I would get more range ( 68 miles ) from a full charge, but I guess it's winter in Berkshire, I had the heating on, driving at night, passengers,etc. once we got to a low range the heating was turned off, this then caused another problem, the windscreen kept misting up!!

The wife wasn't impressed I can tell you.
 

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Discussion Starter #4
68 miles sounds about right to be honest with heating and passengers at this time of year. I certainly wouldn't expect much more.

In summer, with me only in the car, I could comfortably go 75 miles in my Mk1. I reckon on 60-65 miles in winter though. A Mk2, especially with the heat pump, may do 10-15 miles more.
 

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I had turtle once. I originally posted this text elsewhere:

This was before I had a leafdd to report real figures, and I suspect the 95pc indicated by the chademo unit was really more like 85% charged. 65 miles isn't a lot, but this was with heating, 4 people in the car, at up to 70mph, and clearly with 10-15% less capacity than expected

My turtle lasted longer than I expected. It was probably around a mile, I touched that pedal SO gently. Thankfully late at night on a quiet, wide road. I was surprised how quick I went LBW-VLBW -- it sounds odd now. I've had VLBW since, but now I can view GIDs so have a much better handle on state

ANyway here's that original post. Turtle is definately where the stress kicks in.
Not had a recovery todate (14,000 miles,)
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Drove home tonight from the Midlands.

Ambient around 1C
started from 100pc slow charge

Segment 1, around 66 miles. Mostly 60mph. I only got to LBW before reaching waitrose abingdon
Heating was minimal, often 16 only, but about 2/3 through this segment the heating would not heat at all. Unit blowing etc as usual but no heat
This is the second time this has happened. Looks to be sw

Charged to 95pc as indicated by new style chadamo

Segment 2, around 65 miles (I need to check). Initiay 60, 5 miles 70, then dropped to 55 then 50
Heating full time
Got LBW at some point with around 10 miles to go
4.7 mile before arrival got vlbw. Heating off by then. At this point speed was around 30mph and less than 5m to go so not too worried
About 1.25 to go got turtle. What! How so quick
Quiet roads so slowed to 15 mph and managed well over a mile to my drive very gingerly
Scary.

The very rapid drop caught me by surprise..... A close shave
----
 

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I see people using Leaf Spy as this provides much better information than the Leaf dash display.

Is there a version for iPhone users or an equivalent?
 

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Sadly not. Luckily I'm an app dev so whilst iOS is my preferred platform I have to have an Android handset to verify app compatability and so run Leafspy on that. It's worth getting a cheap 2nd hand Android phone just for Leafspy, it's a very useful app.
 

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Discussion Starter #9
Is that an economy of 4.2 miles/kWh?

That makes your battery capacity 23.8kWh... you must have been near totally empty!

Phew! :eek:
 

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100.1! Is that a record? Could you tell us more? Temps? Load? Heat? Driving style?
My average miles/kW is around 3 with mixed driving but no heat.
 

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Discussion Starter #13 (Edited)
Short explanation...

A GID is a way to measure how much power you have. It is a unit of energy that equates to about 80Wh. It gives an absolute measure of energy... not percentage.

The great thing about using GIDS rather than % to measure state of charge is that a percentage changes as the battery capacity changes. It can vary day to day too because of temperature etc but a GID is always a GID regardless of environmental or battery conditions... it is just that the battery holds more or less GIDS depending on its condition, temperature etc.

A new Nissan Leaf battery would have about 284 GIDS or about 22.72kWh when new and over time, with normal use, the number of GIDS it will hold at 100% charge will reduce. When at 100% my Leaf battery has about 263 GIDS. This means that after 3 years and 25k miles my battery still has 263/284= 92% capacity and so my range should be about 92% of what a new car might do.


Longer explanation for those interested :)...

Many State of Charge apps or devices show GIDS and they are a more accurate way to determine the remaining capacity of a battery as 1 GID is always the same amount of energy - about 80Wh.

The Low Battery Warnings are directly linked to GIDS and not percentage. The first LBW occurs at 49 GIDS and the VLBW at 24 GIDS. This is useful to know because you know that the distance you can travel after the LBW/VLBW will be easy to assess as it is always the same regardless of battery condition or total capacity/age etc.

As a GID is about 80Wh it follows that at say a reasonable 3.5miles/kWh a GID equates to about 0.28 mile. Obviously these figures are general and it will vary depending on your actual power economy but 3.5 miles/kWh is about normal for me so I use these as a rule of thumb.

So, using these figures (remember, they are averages and estimates!) there are about 25 GIDS between the LBW and VLBW so I should be able to go about 7 miles and that is about what I find. In fact, by the time I get the LBW I am driving more slowly and often get 10 miles.

Turtle occurs at about 6 GIDS so I should go about another 5 miles to turtle after the VLBW but it is often only 2 or 3 miles for some reason... don't know why. So when I get to VLBW I better be looking to stop somewhere PDQ and hopefully at a charger!

Knowing all of this and having a way to measure GIDS whilst driving means that you can have a great level of confidence on how much power you actually have remaining and you get very accurate warning of when the car will stop. I don't drive anywhere long distance without using GIDS and I often drive past LWB with the certainty that I know how much power I have remaining and so I can pretty accurately estimate how far I can go on the remaining charge. It almost completely eliminates any anxiety.

There are lots of ways to show GIDS. I use a ELM327 Bluetooth dongle which plugs into the diag port under the steering wheel and then I can run the LeafSpy android app on my phone. Other people use a dedicated device such as a LeafDD.

Here is a good chart showing GID capacity vs temperature: http://www.mynissanleaf.com/viewtopic.php?f=44&t=9689#p219991
 

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Discussion Starter #16 (Edited)
There was a guy on Leaf Talk who imported them in batches of 10 once he got enough orders. I was going to get a LeafDD but I found that a £10 ELM327 Bluetooth dongle and my phone works just as well but I don't think there is an iPhone version (?).
 

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Being an iPhone user I bought a cheap second hand Android handset (Sony Xperia X10 Mini) for around £20 that just about qualifies to run LeafSpy. It'll come in handy if I ever check out a second hand Leaf.
 

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Are there cheap android tablets that are equipped with Bluetooth that can run the LeafSpy app, or is it restricted to just Android mobile phones?
 
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