"T i m" wrote in message
...
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.
Well then you need to balance the cost of batteries against enjoyment.
Same as with our campervan.
If it dies, I buy another. Peanuts in the scheme of things.
Ok so we have no TV for a night, the world doesn't end.
Oh wait,
Monday, Wednesday or Friday the world DOES end