New forum member from the UK.
I have owned a 30kWh Tekna new from the end of December 2015; it was one of the earliest ones off the line in Sunderland. It has done 38700 miles.
Not having looked at any owners forum for months, I became aware that my summertime battery capacity appeared to have fallen since my driving pattern is fairly consistent and this time of year brings ranges of 120 miles and occasionally above. Not this year; indicated ranges at 100% charge hovered around 100 miles no matter how carefully I drove and how low I kept my speeds. So when I checked the forums and saw the stuff about rapidly deteriorating batteries I decided to see my dealer, just 5 miles away. Just before I did, I saw the news of the BMS software upgrade that had been issued in the USA.
It was a total surprise to my dealer, who went to check on his computer and discovered that Nissan UK had issued a similar modification notice within the previous day. I booked in for the software change, since checks on rapid chargers that showed the exact number of kWh being delivered gave figures of around 21.5 kWh for a battery showing an indicated 10% charge at the beginning of charging, a massive capacity reduction. The software upgrade was done on 21st June 2018.
After the software change, I recharged to 100% on a home charger (approximately 7 kW) and got an indicated range of 105 miles at 100%; not good. I have driven the car around since and its indicated range appears to be rising slightly pro rata to the indicated percentage energy left, so I have hopes for the software change.
I bought Leaf Spy Pro just after the software upgrade and am looking at the results now. At 43.9% SOC (the car reports 44%), Leaf Spy reports 11.5kWh, 148 GIDs and a SOH of 95.24%. The battery cells page is showing min/avg/max figures of 3.742/3.748/3.754 respectively. Hx is shown as 83.33%.
If anyone would care to interpret the above, please do so. It appears to me that the car is showing its battery is in an excellent state of health but the range and capacity are way below what they should be but perhaps I am interpreting my experience and the above data incorrectly.