Is this normal?
There is a 5% reserve, but I expected it to be able to put out more power?
9.5kwh battery only discharges 8kwh
NSR2 Try a search on 'battery power' and you'll find a wealth of info. AIUI there is quite a challenge in obtaining extremely accurate 'levels. The best estimate is made based on voltage, temperature and goodness knows what else. The 9.5 kWh battery actually has a higher capacity than 9.5 to allow for the vagaries, degradation etc.. The 'reserve' is to ensure that the battery never gets really flat and if it does take a momentary dip it will ensure that it is recharged to that level.
The 9.2kWh battery is supposedly 100% DoD, so you should see the full figure discharged.
Might be worth, if you haven't already, fully charging and discharging it a couple of times then see what you get after that.

should get about 9 from it. 4% reserve plus a bit for conversion losses