Battery life
robinsnest
Member Posts: 3 ✭
I have a 2010 Rinker 310. I have installed an extra house battery but within an hour at anchor they run down. Firstly is this normal and if not what could be the cause? I have 2 fridges and the tv drawing power.
Comments
there are no true marine batteries left- there are instead hybrids that are both starting and supposed deep cell... the only deep cell batteries left are golf cart or industrial lift motor batteries, though the thin plates have made their way into that market too... leaving 8v golf cart batteries as the last remaining stronghold for true thick plate deep cell batteries capable of closing in on 1k charges from below 50% capacity.
8v don't do you any good... but there are some 6v's that will, that can be had in 180hour ratings @20a and ran in series to give you 12v...
you can do what you like, and the space you have dedicated to them will dictate much- but for a house battery separate from the starting bank, it's a no brainer to run two 6v's w/ 120+ hour ratings. they will charge for years, and will take much longer to deplete than the current gaggle of pretend 'marine' batteries. so long as you don't drop them below 50%, you'll use them for a long time... ANY battery, once drop below 50%, has a fuse of 'useful life' lit... most won't charge more than 100 times afterward..
if you run a microwave or toaster, blender or air conditioning off that battery, one that isn't a true deep cell, you're depleting it with a quickness- the thin plates are intended to provide a steady high amperage for a short duration and charge quicker afterward off the alternator.... they can't handle steady loads.
The 6v's you'd be running in series to double voltage, which means the amp hours stay the same. So.... 210 total.
In theory, the 31's would last longer.... but the truth is the 6v can be had as a true deep cell, which will tolerate deep discharge a lot more than the 31's, which just aren't up to the task... they're awesome for short duration high amp loads, but not at all for steady long pulls...
So... lets say you go out this weekend.. the 31's as you have them will last longer in theory. The 6v bank will last 2/3 the time. Let's say you do this every weekend over the season... the 31's will be replaced no later than every two years... the 6v bank, you can expect five years from...
Cost wise, the 6v are marginally more up front. Theyll catch and surpass the 31's in two years without question. They will survive the rigors of house use mucho better than the hybrid 31's...
Sorry robinsnest for taking this off your OP.