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Or rather, for getting home when the "Very Low Battery" warning comes on and unhelpfully the %battery remaining disappears, along with the estimated number of miles range a bit later.

So my question is, what's the best speed to travel at to maximise range - particularly in a situation where you have a few miles to go but hardly any battery. Is it simply as low as you can? Or is 30 or 40 actually better because tyre friction becomes relatively less important and you have some momentum to go up hills?

FWIW I opted for 30mph and got home without a problem, the low battery warning having sounded about 12 miles from home and the very low one about 7 miles later.
 

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I read somewhere that 18 mph is the optimal speed - very little wind resistance and not much power required.
 

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Hmmmm, but wouldn't going very slowly mean using more of your power to top up your 12v battery, particularly if dark and raining ?
 

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Hmmmm, but wouldn't going very slowly mean using more of your power to top up your 12v battery, particularly if dark and raining ?
How much juice would the 12v battery take to keep topped up? if the traction battery was on the last legs of it's charge,surely the 12v draw would be irrelevant by that point..
 

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I read somewhere that 18 mph is the optimal speed - very little wind resistance and not much power required.
Yeah same here, below this the parasitic loads start to become higher than your driving loads. In very cold weather the speed will be slightly higher as your heater will have a higher draw.
 

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Basically as slow as you can safely go down to about 20mph. Below that it is less efficient and so uses more power. I found 25-30 gets you a long way.

I have had to stretch out the power once or twice to get to the next charging location and it is scary... not just the idea that you might run out and need recovery but because as you slow so you become a mobile chicane and get in the way of normal traffic. If you slow below 40 on a fast road I would put on my hazzards. I know strictly it is illegal to have the hazzards on while in motion but I would rather theoretically break the highway code and be safe than have someone rear-end shunt me.

If you need to go into this kind of "get me home at all costs" mode remember... shut off all unnecessary loads - heater, radio, phone charging etc. I have even folded in my wing mirrors to reduce the drag a little. That may not make a great deal of difference but when you are that low it calls for desperate measures!

By far the best tool to have, if you have an Android phone, is LeafSpy... or if no Android phone, LeadDD. With those you can see just how close to zero you are and also gauge if you will make it allowing you to stop at a more convenient spot if you won't. I highly recommend these tools for any Leaf being driven on long trips or down into the red zone. It has saved me being recovered and they are fun anyway.
 

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I thought I read Nissan quoted max range at 38mph at one time? On the range chart often quoted for the leaf here http://www.mynissanleaf.com/viewtopic.php?f=31&t=4295 it mentions in the notes max range at 12mph (exactly, not ave). Apparently that chart was derived from empirical data - l had always assumed it was modelled. Too slow to be practically useful though (except in cruise around Millbrook "because you could" ?). But as it is condition dependent there is no right answer.
 
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