I have 7 smoke alarms and when the alarm begins to beep I usually wait the for weekend and then attempt to find out which one is dying. This time I was too late.
Fortunately I borrowed a multimeter from a work colleague and found the dead battery. His multimeter is an old Disk Smith one which requires a battery to power it. I have read that these should be avoided if possible.

I am now thinking that I need a device to test any sort of battery. I can only imagine myself using it for testing batteries and I figure it should last for a long time (or at least until AA, AAA batteries are obsolete).


Can anyone recommend a battery tester. I have seen cheap ones for $5 and multimeters start at say $30-$40.