When is an AA cell considered as discharged, and how long should they last?

[Justin Passing]

There IS something odd about cat flaps! We had a few.
I noticed some of the Star Ratings complained that the batteries drainied very quickly, but I needed the type being complained about.
Sure enough, cheap alkaline batteries were done in 2-3 weeks, but the poshest Duracells lasted a year. Presumably something about the particular load - a solenoid plus a long slow draw.

 

[ericmark]

There IS something odd about cat flaps!

You have hit the nail on the head, I know good quality batteries/cells do last a lot longer, but which ones Optimum, Plus, Classic, and simple from Duracell all claim more power to an alkaline battery/cells, even when they are also alkaline batteries/cells, although not carbon / zinc batteries/cells.

It seems some designed for high power, and some for long life, but there seems to be nothing to tell one which are which.

 

[ericmark]

Ups, was looking for leaf blower found this out of date, pack of 22 AA cells

seems they only last 3 years, where the Duracell last 12 years, it is such a pain programming the TRV heads after putting in new cells, unlikely to use these. Seems worth around £9 I would pop them into a torch, but not got any torches still needing AA batteries.

And why do they have lead in them? Zinc, and carbon, OK, but lead, really?