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Discussion Starter #1
I'm curious to find out how many miles per Kw i should expect - when driving in the dry, at a steady indicated 60mph, in average temperatures (tyres at 40psi, tracking checked), dual carriageway with no major hills. I recently did a couple of journeys of about 25 miles, and noted battery levels at start/end using LeafSpy, and then did an 'accurate' calculation which gave me an average value of 3.25 miles per Kw. The dash readout on my Gen1 is rather rubbish, which is why i resorted to LeafSpy. I'm wondering if this is reasonable, given the speed, or whether i should be nearer 4 miles/Kw ?
 

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Same conditions, no heat, about 4.2-4.5 miles/kWh indicated at a steady 60mph.
Have done a lot of long journeys so well used to getting this.
2017 30kWh Tekna
 

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Yep at that GPS speed I'd be getting 4.2 to 4.5 summer to autumn, haven't done the wintry depths yet.
 

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Discussion Starter #4
Hmm, now i'm wondering whether i've some kind of fault that's reducing my mileage. I don't think the brakes are dragging (recently had rear pads replaced, front were OK). Am struggling to think what else might cause reduction in miles per Kw.
 

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Headwinds? You aren’t going to notice it much in the car but will most certainly make a difference. It is possible to do the journey out and back? I always find poorer W/m early in a journey while the battery is still cold vs consumption later in the same journey once warm.

I have once forgotten laptop only realised when I got to the office and then drove home and back to the office.

Second journey to the office and this is through a 50mph average speed section of the M4 so pretty constant re conditions was much more efficient than the 1st one of the morning when cold from sitting overnight.
 

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Discussion Starter #6
The journeys were out and back, so only 50% headwind possible. Also, i'm in Scotland - and am acutely familiar with 'blowin a hoolie' and the consequence upon efficiency. My measured trips had light/no winds. Both journeys were evening, and not cold.

Last summer i know i could do a 60mile roundtrip (it's a 2012 with 78% SoH - has a capacity of about 16-17Kw), yet now i very much doubt i could do that. So, i'm wondering what might have changed...
 

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16-17 is a wide range, what does leafspy say on a full charge? it should report GIDs and KWH.

One thing thats maybe throwing you off is the lower buffer stays fixed at 4kwh as the battery degrades. So you get the low battery warning sooner and sooner as the capacity goes down.

Or it might have a bad cell that loses charge quicker than the rest, again, you can see this in LEAFSpy by looking at the cell voltage screen.

Personally i've never got near the figures many on here claim to achieve. But i do tend to drive at 70mph (77 on the LEAF speedo) for most of my journeys. If your tootling along at 60 on the LEAF speedo and only getting 3.25mi/kwh that does seem pretty awful. Lots of AC/Heating maybe? I managed only 2.68mi/kwh on a 20mile trip last saturday in the bad weather with the heating and AC running the whole way.
 

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Discussion Starter #8
I'm fairly sure i don't have any weak cells - the balancing usually looks OK, at high or low SoC (low SoC has more variance across all cells). Certainly, there isn't one consistently weak cell. I used the heating/AC very little on the test runs, to avoid this confounding actual range.

I've found that the charging stops between around 16.2 and 16.7Kw - reported as about 90% SoC (209 GIDs, SoC 90.5%, 16.2kWh, 2,861Wh). This has bugged me, as i never get to 95-100% (indicated/reported - i know that it won't charge to actual 100% to conserve battery performance) - the extra few percent would come in handy on some longer trips. I was told that charging stops when a cell hits 4.1V, and this seems to be the case.

So, i'm still wondering whether there's a mechanical reason behind my 'low' miles/Kw - the car seems to go less far than it used to - and this is a pain ATM as i've a 50 mile 'regular' trip; and hate driving off the bottom of the bars... Maybe time to think about a battery upgrade.
 
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