What's the Hybrid battery charge supposed to be?

I'm questioning the SoC levels on my car. These days in Sydney, it's been around 42C (~110F) and obviously one needs to crank up the A/C to maintain a level of sanity. One morning, I had the A/C going, drove a short distance before the car fully warmed up and restarted on my longer journey however, the SoC dipped to 32% which is way lower than what I've been used to seeing on the Scangauge. Ever since, it's been floating around the low 50% and I'm struggling to keep it over 60% without some nice downhill. Aggressive acceleration and braking will lift the charge but it gets used up as per normal. Maybe because the A/C is constantly on drawing power or maybe the traction batteries is on the way out(?). It's one of the first Gen3 built (Apr 09) so not sure if that has anything to do with it (generally first few months build are the "experimental" whilst the factory gets it right).

 

System is designed to keep battery charge between 40% and 80%, in order to maximize the lifespan of the battery. Rarely will you see 8 bars.

 

I get the sense, that you're getting the sense, that something is different in the battery's behavior. Could be. How many miles on it?

I think the dealership can perform something called "hybrid health check"? This link is to UK; maybe you can get this too:

Hybrid Cars Health Check | Toyota UK

 

Hi Jack: I also notice that battery start to charge from 40%, but seems it already approaches to damage level of the battery (as it voltage is really low). So is there any way can make the battery start to change SOC from 40% to 45%?