I have a 5.5 kw Hubble AM 2 Lithium battery mounted in my garage.In winter does the performance of the colder battery drop off? I did a test one night and switched off my mains and not a ton of stuff in the house was powered by the battery overnight but in the morning it was down to 32% soc.Was wondering if in the warmer times the drop off will be less.

Batteries lose their capacity as the temperature goes down. It's 100% at 16-25C and goes down to 50% at -20C, so as it gets colder your battery won't charge to full capacity.

You can check the datasheet, but is should be similar to this:

Also don't forget that even though it's not a lot of stuff on overnight, your Inverter consumes typically 45-65W as well. That alone is half a kW over a 10hour period.
I manage my single AM-2 carefully and it usually is down to 30-40% SOC every morning.

Here is an example.
My typical Load is anywhere between 70 and around 200W when the fridge kicks in which is clearly visible at just after 3:30.
The rest of the flatter spikes is my 12 V battery charger. I run my Cameras and Network Switch off independent 12V.

For the same time period you will see that the Battery Power is around ~60W more throughout. This internal consumption by the Inverter is not reflected in your Loads.

So considering between 150 to 200W usage from the battery, with the current near 15 hours of no solar, that would be 3kW usage already. These low loads are only after bedtime. So typically it is around 200W more earlier in the evening and then the kettle spikes can be seen way before the sun really beats down in the morning.
Thus the 30% SOC in my case is just reality.

Many thanks for the feedback.It does tally with what I saw so all good.Roll on spring with warmer temps and longer sun hours for our panels to earn their keep.

23 hours ago, Adagio said:

You can check the datasheet, but is should be similar to this:

Nice graph.

Remember that most AM-2 batteries are in a garage / shed as they are not IP65 rated.
In JHB, the typical indoor temperature rarely drops below 15C (Lowest I've measured 16C indoors)
At 15C, there is only a 1.5% drop in capacity.