Batteries for a 30ft liveaboard

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Heya,

I am looking to replace my leisure battery on my 30ft sail boat, I’m new to boating and don’t know a lot about electrics!
I am planning to live on board, and run minimal electrics: phone and laptop charge, cold plate for fridge, led lights, led deck light? VHF radio charge maybe a small fan if we have allowance for it.

I am looking to also get two solar panels and all the bits that go along with them- however, what confuses me are the reviews of lithium vs gel vs traditional batteries. I’ve seen Trojan deep cycle recommended for live aboard...

What have people had good experiences with?
What’s your set up? Does it work well?
What would you change?
What is the standard to have aboard? I purchased my boat with a pretty agricultural set up, but that was reflected in the price.

Thanks,
any comments greatly appreciated,
Taylor
 
I think people will need a lot more information; do you have a seperate battery for engine starting and do you have access to shore power for starters. Your fridge will take a lot of current.
 
Heya,

I am looking to replace my leisure battery on my 30ft sail boat, I’m new to boating and don’t know a lot about electrics!
I am planning to live on board, and run minimal electrics: phone and laptop charge, cold plate for fridge, led lights, led deck light? VHF radio charge maybe a small fan if we have allowance for it.

I am looking to also get two solar panels and all the bits that go along with them- however, what confuses me are the reviews of lithium vs gel vs traditional batteries. I’ve seen Trojan deep cycle recommended for live aboard...

What have people had good experiences with?
What’s your set up? Does it work well?
What would you change?
What is the standard to have aboard? I purchased my boat with a pretty agricultural set up, but that was reflected in the price.

Thanks,
any comments greatly appreciated,
Taylor

If 10 people reply, you'll get 12 different answers :)

As per post #2, some more info would be helpful. What do you have now in terms of batteries, switching and charging ?

Where will you be sailing? Where will you keep the boat?
 
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What have people had good experiences with?
Trojan T105!! :cool:
Number one rule for long lived and happy lead acid batteries, get them really, really fully charged often like once a week, takes a long time to actually get full again, most batteries are murdered.
A high percentage of cruising boats never plugged into the main don't get the batts charged to full and then wonder why they die so quick.
Which means lots solar and a half decent battery monitor to see how many amps are going in/out.
Lots info on good info here about lots of boaty things :cool:
Congrats with new boat, now you will always have a good escuse to buy nice tools :)
Batteries Archives - Marine How To
 
Without 3 of the things on your list there is no problem whatever: The Fridge The Laptop and the Fan (if you, perhaps, mean a simple heater).

However with those three things ( which as an all around liveaboard I can see you might want) you will have to make some compromises and careful decisions. They are the items which take things to a tricky level.

.
 
As others have said more details are needed for specific advice. But having explored the use of LiFePO4 (LFP) and installed it on my own relatively small boat, I think you would be well advised to give LFP a miss for the moment. As prices have fallen, many companies are offering drop-in replacement batteries and make it sound oh-so-simple. It really isn't straightforward and easy to make expensive or even dangerous mistakes. However things are changing and to future-proof yourself, if you do need to upgrade any chargers (mains or solar), now or in the future, then buy products that will work with all the battery chemistries including lithium and that allows a wide range of user settings easily changed with Bluetooth and with updatable firmware. Victron Bluetooth products are excellent for this.
 
Leoch Pure Carbons are great, esp. the 210Ah versions. Nice and heavy to use as ballast, much cheaper than lithium, but you can fast charge, deep cycle and abuse them much like lithiums.
 
To go lithium you need a good amount of money to do it properly. Sealed Lead Acid deep cycle batteries are good enough for your needs and 2x100 AH batteries or a slightly larger bank is ok. Golf cart batteries (6v) are a good choice as they are made for heavy-duty use. More important are your solar panels which they should have feed the batteries by sunset, so they can stand the loads during the night. In Greece 2x100w panels would be more than enough during the summer and maybe in winter also. ( i had the fridge working only with a 100w panel in the summer, i was rarely running the engine a few nights for some boost) I assume that in higher latitudes with permanent cloudy skies, you would need more solar than this.
 
Leoch Pure Carbons are great, esp. the 210Ah versions. Nice and heavy to use as ballast, much cheaper than lithium, but you can fast charge, deep cycle and abuse them much like lithiums.
My point is that with the new Lead Carbons, you get a lot of the benefits of lithium, with the value, ballast weight and benefits of AGM.
 
As said the question is not so much what batteries but rather what charging source. If you have shore power then no great problem and really only need good batteries when you leave shore power.
If you do not have shore power then your options are solar and engine or separate generator power. Solar will be somewhat limited. Firstly by the size of panels you can fit and it is likely the cost of a mounting gantry will equal or exceed the cost of the panels. The likely amount of solar panels you can reasonably accommodate are unlikely to provide for your needs. At least not all the time. Much depends on weather and latitude. tropics perhaps ok but not northern Europe. Either the refrigerator or the heater is going to be your main electricity consumer because they are used for a long time.
So batteries only smooth out the requirements and will not generate power for you. Probably a pair of Trojan batteries 2x6v will do you well. But you really need a separate battery fro engine starting. ol'will
 
During summer, I managed fridge, lights etc living aboard. Charging phones. Occasional use of an eber type heater, with 2 x 105ah leisure batterries on the house side, and 200w of solar. Could survive the occasional rainy day, but by the end of 2 they were getting low.
 
One possible constraint on the size of the banks you would like is the footprint space you have to put them in, so whatever a/h size battery you look at chech it against other batteries with different a/h.
ie there are 100ah batteries with the same footprint as a 130ah battery and you can get two 85ah batteries with a footprint that is only slightly longer, so measure carefully.
 
I've been living aboard full time for the last 10 years and I've come to the conclusion that the best option (assuming you're plugged in to shore power most of the time) cost/benefit wise is decent quality lead acid batteries and look after them properly. So if replacing mine I'd be looking at whatever lead acid batteries of the required size are on offer from a reputable supplier (e.g. Tayna) and that's what I'd go for. Possibly subject to change if/when the cost of some of the newer tech batteries becomes more realistic...
 
I live aboard in the Med. 4 Trojan T105s, 200W solar with a Victron mppt controller, plus alternator and mains charger running a small fridge, six fans (I fitted three just for English summers) and the usual lights, instruments and chargers for phones and tablets on a 10m boat. I'm well happy with them.
We have sustained greater than 50 percent charge after 10 days at anchor in summer, changing the angle of the panels once or twice a day on most days. In winter they need mains charging once a week, more on the rare cloudy weeks.
The Trojans are six years old now and seem to be holding up well.
The solar panels never get the battery bank up to full charge. We need mains or long engine runs for that. I had a Sterling alternator charge controller that used to be great at squeezing in the last 20% until it went kaputt. I can't afford to replace it and haven't the skill to repair it. But its a piece of kit worth having if you go off grid and will need to use your engine for bringing the batteries up to 100% charged.
I bought a generator thinking I'd need it living on the hook. Couldn't fit it in when we left the UK so I sold it. Haven't missed it.
 
ah per £

make a spreadsheet and choose the maximum for your budget.
lithium may last longer but no one knows for sure yet.
AGM are fit and forget
if you have a fridge you will need plenty of capacity and as much solar as you can manage.
 
We have a 24 foot Snapdragon with 40w of solar power. In summer, for Solent pottering, it keeps up with our needs, as long as we don't use the cold box. In winter, it charges the batteries over the week after a weekend aboard.

As for batteries, as a liveaboard, unless you're going to be hooked up to shore power almost all the time, there's no such thing as too many amp hours; the limit is weight and space. Lithium is what I'd have on my superyacht, but too rich for most of us. I'm unconvinced that AGM is worth the extra cost for most applications, so I'd go for leisure batteries from an online supplier like Tayna. I have a Numax on my boat and it seems fine. It's a few years old and still going strong (famous last words...). If you haven't got a separate starter battery, get one. That way, if you run your domestics down, you can get the engine going to charge 'em back up. Fit a VSR so everything charges from the alternator.

Solar: again, there's no such thing as too much, just not enough space and not enough money. Overall, the most reliable and cheapest are rigid panels; The flexible ones claim you can walk on them, but that seems to be a recipe for early failure. I have a PWM controller that handles two battery banks; I have it set up so it charges the starter battery first, then switches to the domestic, on the basis that a flat domestic is an inconvenience, a flat starter is a serious pain. An MPPT controller and makes better use of the power from the panels, but last time I looked, I couldn't find one that could manage two banks. They're also a bit more expensive. The enemy of solar is shade. A small shadow can reduce output from the shaded panel very significantly, so two or more smaller panels is generally better than one big one.
 
If 10 people reply, you'll get 12 different answers :)

As per post #2, some more info would be helpful. What do you have now in terms of batteries, switching and charging ?

Where will you be sailing? Where will you keep the boat?

Thank you for replying!
I realise now people can’t read my mind haha, I plan on using shore power as sparsely as I can.
Ive been spending the last leg of lockdown working on the boat, and plan on placing 2 100W solar panels, with all the kit, above a home made Bimini.
I plan on sailing to the med and making sure I see everything along the way- but I will have quite a small budget of a few hundred pounds a month- with friends and family dotted around for a few cheaper stays haha

I have a new starter battery from my experimental trip around the south coast of the England, so hopefully this shouldn’t need replacing.

Trojan batteries are looking like a good place to start looking into.

Thanks to everyone on this thread it’s been incredibly useful!

Taylor
 
You may already be aware or it might not apply to you but if you're a UK citizen do bear in mind that after the end of this year we're likely to be subject to Schengen visa rules when visiting the Schengen zone. This means 90 days in 180 so bumming around the Med won't be quite the same. Sorry if it does affect you and if this is the first you've heard of it...
 
One more thing, mentioned once already. Get a battery monitor. My NASA BM1 is a godsend. There are better monitors but NASA is cheapest and is good enough. I also check the specific gravity of my Trojan batteries every month or six weeks when I top up the water. This helps me to understand what my battery monitor is telling me and to be more confident in the actual health of my batteries.
Oh, and improve the insulation of your fridge and the cooling of the compressor (I've added a computer fan to it and might add another.) The fridge will be your main battery drain in the summer if you replace lights with LED bulbs and keep the rest of your electrical system simple (e.g. no TV unless you are on shore power. We didn't bother with one.we wanted a change in lifestyle, not just import our UK lifestyle to a boat in the Med.)
 
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