On Sat, 16 Sep 2017 00:08:47 +0100, "bm" wrote:


"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.

Now, as an aside, because we may only go electric outboarding 10 times
a year, we may decide to push the battery to say 100% DOD (which is
near 10.5V, *not* 0V etc) because, according to the chart, even at
100% DOD those batteries should offer 450 cycles which would mean 45
years use at that usage rate!

However, the closer you go to 100% DOD the greater chance of doing
irreversible damage to the battery, something I'd prefer to avoid.

That said, once we have the potentially 'arbitrary' 50% DOD covered,
it would only be a matter of changing a couple of numbers to allow any
program / formula / calculation to adapt accordingly and take it to 60
or 70% DOD. Better run time at the expense or a lower cycle life.

Cheers, T i m