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OK, so how much does temperature affect the overall available power? I noticed over the past couple of weeks that on a 'B' trip reset, what had been 186 miles was now in the 170's. Did a check with CanZE last night and see that we're down to 99%SOH after 7.1k miles but total available charge adds up to around 36kWh (25.6kWh used and 10.7kWh available). This was after around 100 miles yesterday with the heating running most of the time, and battery temp showing at 12 degrees.

After charging overnight, it now shows as 38.4kWh available. Battery temp still showing at 12 degrees, although air temp is nearer 5.

Are these variabilities due to the way CanZE interacts with the 41kWh BMS, or is there some anomaly around temperature and battery capacity. Either way, 36 or 38kWh is quite a bit less than the advertised 41. If it were much warmer, would 40kWh be more likely on a 100% charge? @yoh-there can you comment?
 

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Co-author of CanZE. Q210 nov 2013
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In my experience you loose roughly 25% range between summer and winter. This is due to decreased capacity (which recovers again in summer) and heater usage, which accounts for roughly 10% while driving on the motorway, but more when in start-stop-low speed traffic. Preheating does offset this a bit.
 

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Yes, that's my experience too. What I've not done before it to try and scrutinise the reported battery capacity with CanZE. In high summer I had a SOH of 101% and a reported 39.9 kWh capacity. I now have 99% SOH and 38.4 kWh. I guess my question is, loss of range isn't just to cold weather meaning more energy required to heat then, but that overall battery capacity is also reduced? In the current instance, 1.5kWh less with a 12 degree battery over 24 or so.

SOH is therefore more than just the battery capacity then, as 101% to 99% should mean I'd still be able to charge to 39.1kWh..
 

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Co-author of CanZE. Q210 nov 2013
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Speculation alert, no proof!

I don't think in the ZOE SOH is a percentage of nominal energy (kWh) content. It MIGHT be coulomb (Ah) content, not sure. But I am sure I never saw SOH vary in the same way as the range; not even close even when mentally compensating for the A/C consumption. Actually, I don't even think I ever saw SOH going up (in spring).

So either ZOE is compensating SOH for temperature, or, if SOH is indeed Coulomb content, energy content decreasing is strictly a function of lower battery voltage. I haven't checked this with relevant documentation / research to be honest.
 

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Been meaning to contribute to this thread for a while. My Q90 (batteries rented) started off 102% when brand new. At 3,800 miles I got the STOP Electrical Failure and my battery was replaced/fixed by Renault. When I got it back it was 100% SOH. I do fortnightly commutes from Glasgow to Manchester/Derby, so easily over 90% of my charges are on the rapids. Seems to have suffered with the heatwave we had but once it hit 97% in mid-August it has not moved. I even joked with my petrol-head brother-in-law that my battery's health had flat-lined. We'll see how it progresses during the winter.

That said, battery fan behaviour is sometimes erratic. Most times the fans come on at 26c to 31C but once I had the battery hit 42c and no fans came at all. Strangely, after 19 miles after it stopped charging it had dropped dramatically down to 29c.....and then the fans came on when I plugged in my granny cable at home to top-up

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My Q90 i at 19,400 miles ( June 2017 ) 18 months old , now still on 97 % same as when checked in August 2018.
I sometimes Rapid charge once a week ,But mainly use 7kw post's when I am out and about.
Plus if I use a Free Rapid and the battery is still not that warm then the Charge received maybe under 20kwh so may not be a Rapid charge at all.
 

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Co-author of CanZE. Q210 nov 2013
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Degradation is supposed to slow down; the curves should flatten over time / distance. My Q210, with admittedly the newest firmware installed 15 months ago, which some have marked as "Battery-gate-ware", and admittedly is quite a different battery, is after just over 5 years and almost 100.000 km 97%.........
 

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Ze Q90 i June 2017 Brand New:

Sept 2017 @ 101% @ 4,600 miles
Feb 2018 @ 100% @ 8,000 miles
April 2018 @ 99% @ 10,900 miles
June 2018 @ 98% @ 11,800 miles ( One Year Old )
July 2018 @ 98% @ 14,500 miles
Aug 2018 @ 97% @ 15,211 miles
Dec 2018 @ 97% @19,400 miles
Feb 2019 @ 96% @ 21,250 miles
April 2019 @ 96% @ 23,495 miles
 

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Meant to post this last week you just reminded me. :)

New in June 17, March 2019 SOH 98% @ 14500 miles.
 
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