So I know everyone can agree that leaving a
battery in a partially discharged state is bad. My question is how long is a partially discharged state?
Let's say you have a 870ah bank and on a
passage you use 240ah per day (10amps per hour). You have
solar panels that put 60ah back into the bank each day. So by my math that means your net usage is 180ah per day which would give you 2.4 days of
battery power before needing to be recharged. So that leaves your
batteries in a partially discharged state for 57 hours. Now my assumption is once every now and then is ok but if you are on a 30 day
passage that means you are constantly leaving your
batteries in a partially discharged state for most of the passage. At what point does this become detrimental?
To me it would seem ok during the passage but on the flip side if I were to partially discharge my bank and then leave the
boat for 2 days without any
charging and then come back I would feel like I was damaging the bank.
So how much is too long to leave a battery in a continuous discharged state in this fashion?