[Elecraft] K2 - Internal battery life?

[Dave G4AON]

Rick

In common with other lead-acid batteries, the battery used in the K2 
suffers when
discharged to any extent. Unfortunately, the only method of using a 
lead-acid battery
that will keep it near top condition is to only lightly discharge it 
then re-charge it
immediately. You will often see ex UPS batteries for sale on eBay that 
are 18 to 24
months old, they are usually replaced because even using high 
specification batteries
and careful charging, they have a very limited life.

I've tested a few lead acid batteries, both of the gel cell and "wet" 
types, they all
lost capacity when discharged to 11.5 Volts, recharged and tested a 
second time!

Car batteries "last" for 5 or 6 years mostly because they receive very 
little discharge.

I've come across a lot of radio and similar equipment that uses sealed 
lead-acid batteries,
but only where they have been abused by constant overcharging have I 
seen cells damaged -
even then it didn't rupture the case.

I've changed my K2's internal battery once, it's a 1999 vintage K2. I'm 
not sure what the
present capacity is... As the batteries aren't very expensive, it's 
probably worth changing
them every couple of years or so. If you really want to test capacity, 
the West Mountain
computer battery analyser is a pretty useful item:

http://www.westmountainradio.com/CBA.htm

73 Dave, G4AON K2 #1892

Rick wrote:

My K2 No. 2005 (I think I built it late 2000 or so) is probably 6 or 7

years old. I have it set up with the remote 100 watt amp/tuner and the
K2 itself with the low power tuner and internal battery option. 

My question is how long can I expect this battery to last? My greatest
fear is someday opening up the K2 only to discover acid leaking out
from the battery onto the main PCB. Has there ever been an instance of
the internal battery leaking?

Rick
K4LX
No. 2005