Some rechargeable batteries are better than others
I used to think all rechargeable batteries were the same. They're not.
A big reason I buy regular alkaline batteries (in a 36-pack for AA size, thank you very much) is because over the years I've had bad luck with the rechargeable stuff. At first, yeah, the rechargeable is good and does the job... but only at first. After a few charges, I'm only able to get maybe 50% of the charge I used to at best and then stick a fork in it, it's done, throw it out. And that's no good.
Rechargeable batteries now have grown up, so to speak.
What I mean by that is that you're now told outright what the mAh is. The higher the mAh, the longer the charge, the longer the battery lasts over time (usually).
And example is the AA rechargeable in 2400mAh flavor. That's a true high-capacity, and it comes pre-charged. Yes, good. I like that. That actually sounds promising.
Then there's the AAA in 850mAh flavor. This is labeled as high-capacity. Is it? I don't know about that because 850mAh doesn't sound that great.
However, then there's the 1100mAh AAA rechargeable. Okay, now we're talking. And oh yeah, not cheap. For an AAA battery, that is.
The one that really blows me away is the 5400mWh 9V rechargeable, and it even comes with a charge cord included. Surprisingly, not that expensive for what it is. I may go for this at some point because even though I don't have many things that use 9V, the 5400mWh would be oh-so nice to have.
In the end, mind that mAh or mWh rating. It matters. A lot.