How to keep your batteries healthy and long lived

[conachair]

Bit of an LX refit on the go, so on a full time liveaboard on the hook boat, this is a sort of overview to try and get the best out of deep cycle batteries, trojans in this case -

• Get back to real full 100% as often as possible, couple times a week hopefully worst case on this boat. Usually most days.
• Try not to cycle too deep, looking like 75/80% for a normal night on the hook.
• Equalize once a month or so, maybe a bit less if SG of the cells have very little variation.

Would be nice to keep them nice and cool as well, not that easy though..

Simple really, in concept anyway...

So can anything else be done to keep your batts looking at a long and happy life?
(general watering ,cleaning etc assumed)

[puffcard]

Check electrolyte levels and keep them top off.
Used only distilled water to replenish.
Keep battery tops clean.
Check connections and use protective grease.
With FLA make certain you have ventilation.
Make certain they are secure and isolated from vibration.

[conachair]

Originally Posted by puffcard

Check electrolyte levels and keep them top off.
Used only distilled water to replenish.
Keep battery tops clean.
Check connections and use protective grease.
With FLA make certain you have ventilation.
Make certain they are secure and isolated from vibration.

Kind of hoping generic maintenance stuff like that would be covered in the, maybe not explicit enough -
(general watering ,cleaning etc assumed)

[smac999]

getting to full charge is almost impossible without shore power. even with a gen it's not going to happen. pretty much the only way is with a gen and a lot of solar. run gen in the morning for 1-2 hours, with a large charger. like 100a depending on bank size. then let solar float rest of day.

one of the important things is the proper charge voltage for your battery. alternator, charger, solar etc all need to be set to the correct voltages.

[DumnMad]

These vloggers have been living off the grid 30 years with Trojans. 7.5 to 10yr life and no fancy monitoring systems.

https://www.youtube.com/watch?v=9H7a1Jz-Phc

[conachair]

Originally Posted by smac999

getting to full charge is almost impossible without shore power. even with a gen it's not going to happen. pretty much the only way is with a gen and a lot of solar. run gen in the morning for 1-2 hours, with a large charger. like 100a depending on bank size. then let solar float rest of day.

one of the important things is the proper charge voltage for your battery. alternator, charger, solar etc all need to be set to the correct voltages.

Regulator set points is a good point worth checking, I never bother with float or rather float is set to absorption at 14.8v.
Also, 'almost I possible ' is a bit strong imho. I manage it more days than not on solar, up to absorption early afternoon with leaves a good few hours to top up to full. Bearing in mind with a lower current input like solar (smaller than a football pitch ) when you do get to absorption voltage it will be more like 90% full, not the oft quoted 80%. Full I s assumed when the current levels out at under 1% of capacity in aH

[conachair]

Originally Posted by DumnMad

These vloggers have been living off the grid 30 years with Trojans. 7.5 to 10yr life and no fancy monitoring systems.

Ta, trojans are great!
Not so sure about no solar regulator these days though when stuff like victron mppt aren't the budget breakers such regulators once were.

[sailinglegend]

Originally Posted by conachair

.... I never bother with float or rather float is set to absorption at 14.8v.

....Full I s assumed when the current levels out at under 1% of capacity in aH

Float set to the absorption voltage is a very very good idea. My Morningstar MPPT controller has an option to NOT GO TO FLOAT.

How often due you get to less than 1% of capacity in Ah? I assume from your post that you will be measuring this at the absorption voltage of 14.8v. Many think they can use this test at Float voltage, which in my case is 4-5 times LESS current than at Absorption voltage.

[a64pilot]

The other thing that comes to mind is proper orientation so that when underway you don’t expose any Cell plates.
http://www.pbase.com/mainecruising/f...ry_orientation

[mikecambrai]

Looking at it from the other direction, what kills batteries most.
Firstly not filling them with distilled water before they run dry. You need a routine for wet cell batteries to check them at least monthly, more if you are using them every day. Once they go dry they are on their way out. That's why I always now buy AGM's or any battery that does not need topping up.
Secondly letting them go flat. Easier said than done when you may have a small bulb somewhere which is taking a small current over the week or month that you are not there. Always have a system that you can go 'dead ship', ie the batteries are isolated from everything.
If you have to have the battery connected to something whilst you are away, like solar(use an MPPT controller which will give you float voltage and prevent back feed when the sun goes down), or the bilge pump(if you are leaving the boat for any length of time it might be better to have a warning lamp on deck and let the marina check if the light goes on, how much water there is in the bilge).

[john61ct]

Originally Posted by conachair

Not so sure about no solar regulator these days though when stuff like victron mppt aren't the budget breakers such regulators once were.

Nobody said no solar controller.

Just no fancy SoC meter like SmartGauge or Victron BMV.

[john61ct]

Originally Posted by conachair

Try not to cycle too deep, looking like 75/80% for a normal night on the hook.

That's 20-25% discharge (DoD), right?

80-75% SoC.

50% is the lowest in normal ops, for longevity.

Just to be clear.

[conachair]

Originally Posted by john61ct

Nobody said no solar controller.

Just no fancy SoC meter like SmartGauge or Victron BMV.

https://www.youtube.com/watch?time_c...&v=9H7a1Jz-Phc

About 7:15 in, sounds like they're running 160W solar straight onto 6 x t105 trojans. Reasoning being I think that the solar can never produce enough amps to damage the batteries, only to give a sort of mini equalization.
Which is interesting -especially if they're getting 9/10 years out of a bank of trojans.

I find charging high interesting, there apparently was a paper publish a while ago recommending this for off grid installations, can't find it online anywhere but thread here references it -
OutBack Power Technologies User Forum • View topic - L-16 recommended charging voltages

The study has four conclusions:
1. The finish voltage (sometimes called the absorption
voltage) for a flooded lead-acid battery operating at
12 VDC nominal should be about 15.3 volts (2.55 per
cell) rather than the customary 14.4 volts.
2. Finish charge time should be at least 3 hours and
often longer.
3. The maximum interval between finish charges should
be about five days.

A problem for us liveaboards is there are some many variables between boats and battery datasheets don't really say what's best for a battery on a boat, just what's good for a battery!

And to do our own research you need a dozen boats to try different set ups and a few decades

[conachair]

Originally Posted by john61ct

That's 20-25% discharge (DoD), right?

80-75% SoC.

50% is the lowest in normal ops, for longevity.

Just to be clear.

Yep, usually not dipping below 75/80% SOC, so only using about 20/25% for the battery capacity. Voltage usually over 12.5 under load in the mornings. 300W solar into 2 x T105.

[conachair]

Originally Posted by a64pilot

The other thing that comes to mind is proper orientation so that when underway you don’t expose any Cell plates.
Installation & Orientation of Flooded Batteries Photo Gallery by Compass Marine How To at pbase.com

That's new one, thanks. Never once even thought about that. Luck on my side, got it right