"T i m" wrote in message
...
On Fri, 15 Sep 2017 23:19:25 +0100, "bm" wrote:
snip

Yes, I was wondering why 50% was specified.
Or maybe I missed it.

50% is often given as the maximum depth of discharge (DOD) as it
typically represents a reasonable output of energy whilst giving a
reasonable battery life.

http://www.mkbattery.com/images/8GU1H.pdf

Ok.