Difference between batteries

[Cornishkiwi]

Looking to change my house bank in my boat soon.

I want 3 or 4 200ah batteries.

I'm after victron batteries but was wondering whats the difference between the

AMG Super Cycle
Gel Deep Cycle
AMG deep cycle
And the Lead carbon

Also out of these ones which would be best fitting for a house bank?

Finally can you have too big a bank? As surley bigger is better?

Thanks

[sailorboy1]

well the only real difference between them is $$$$$

Except for the carbon that I assume you mean carbon foam, not lead carbon, FireFly batteries. The difference between the other AGMs and the FF is that the FF doesn't lost capacity from being left in a partial state of charge like the AGMs will definitely do.

But if you normally have your boat on shoe power floating the battery it is a waste of money and even bad to us FF

[tkeithlu]

Instead of "more is better" consider running an energy budget and sizing the house bank to your need. That would include anough capacity to get you between sources of power such as dockside or solar.

Also consider designing it so that you have backup - isolate the starting battery so it's not dragged down by other uses, and consider an isolated battery for the panel (radio!) in case your house bank gets flooded with seawater. Then get a jumper cable (you only need one since the negatives are bonded) so you can start the engine with the house bank, etc.

This could be a fun project.

[steve77]

Originally Posted by Cornishkiwi

Finally can you have too big a bank? As surley bigger is better?

First, they are AGM batteries, not AMG.

And yes, your battery bank can be too large. If you are using your boat regularly away from shore power, then you need some way to replace the power that you have removed from the battery bank. If your charging source is too small, then you will never get your batteries fully charged, and this is bad for AGM batteries. There are lots of posts here concerning the lifespan of AGM batteries that are left in some partial state of charge rather than being regularly fully charged.

So, if your battery bank is too large for your charging source to keep it fully charged, then yes, having a battery bank that is too large can be bad.

Tkeithlu is right, make an energy budget and see what size battery bank you need. And again, none of this applies unless you are spending a substantial time away from shore power.

All the best!

Steve

[Cornishkiwi]

The boats on a mooring intended to use as a live aboard and would be getting power from solar and wind vein as well as engine and back up generator, so will be constantly using power aswell as having constant power source.

Based on previous comments im assuming AGM batteries wouldn't be the best applicable?

The carbon battery would be better?

[Cornishkiwi]

Or yes looking more into it fireflys seem to be the top choice, however I cant seem to find UK Dealer or Prices?

[more]

Originally Posted by Cornishkiwi

The boats on a mooring intended to use as a live aboard and would be getting power from solar and wind vein as well as engine and back up generator, so will be constantly using power aswell as having constant power source.

Based on previous comments im assuming AGM batteries wouldn't be the best applicable?

The carbon battery would be better?

lifepo4

[Cornishkiwi]

Yeah not for a minute, havnt got that kind of cash [emoji1787][emoji1787]

[mlydon]

Yes, you can have too much battery, Virginia ;-)

Particularly with lead chemistries (anything except lithium), there is a proper charge current range-:tpically around 20-30% of capacity. For instance, I have 4 firefly batteries. They require approx 40 amps PER battery for a good restorative charge. Thus I need to be able to deliver 160 amps of charge current when they start bulk charging. I can do that, barely, with my Balmar 170 amp alternator, and luckily, they take in less and less amps as they charge, so the alternator isn’t flat out for too long

My charger, on the other hand, is only 120 amps - barely enough for my bank. If I doubled the bank, I would need to double up on chargers, upgrade to large-frame and/or multiple alternators, split into multiple banks, or have 2 acres of solar panels on board.

If I were starting fresh, unlimited budget, I’d go with a large lithium bank and ganged chargers - filling the bank with an hour of genset runtime sounds really good to me.

Matt

[ThereAndBack]

Originally Posted by Cornishkiwi

Yeah not for a minute, havnt got that kind of cash [emoji1787][emoji1787]

If you're buying cheap - go with GC2 lead acid golf cart batteries.

If you're buying good - buy lithium iron phosphate batteries. They can be much more affordable then people believe these days.

The lithium batteries will have about double the power compared to a lead acid bank. You can hook your system up for about 2000 usd easy. Less if you build the batteries yourself.

[steve77]

Originally Posted by Cornishkiwi

The boats on a mooring intended to use as a live aboard and would be getting power from solar and wind vein as well as engine and back up generator, so will be constantly using power aswell as having constant power source.

Based on previous comments im assuming AGM batteries wouldn't be the best applicable?

The carbon battery would be better?

If you can provide a charging regimen that will keep the AGMs regularly fully charged, then the AGMs should be fine for you. If you're unsure whether or not you can do that, then the Fireflys are more tolerant of being left in some state of charge less than 100%. Sorry, I don't know of a source for the Firefly batteries in the UK, but that doesn't mean there isn't one.

Lots of people will tell you that lithium batteries are best, but you really need to look at your present electrical system to see they are best for you. It's not simply buying new batteries, and for many people they are not the best choice because of the cost of adding new or replacing existing charging equipment.

Cheers!

Steve

[more]

Originally Posted by ThereAndBack

If you're buying cheap - go with GC2 lead acid golf cart batteries.

If you're buying good - buy lithium iron phosphate batteries. They can be much more affordable then people believe these days.

The lithium batteries will have about double the power compared to a lead acid bank. You can hook your system up for about 2000 usd easy. Less if you build the batteries yourself.

i have more energy in 200ah 12v Winston LiFeYPO4 vs before 420 ah 12 AGM alpha cell.
new Winston 200ah 12v 1275$ last without BMS 7-15 y
alphacell AGM 3.5 hp 450$ x4 1800$ 3-5 year

But you are right if you don't have money buy cheap golf cart battery

[AndyEss]

Along with much higher energy density, LFP batteries for the same useable capacity are about 1/4 the weight of lead acid batteries.
Considering that most boats are continuously moving, have uneven and oddly angled surfaces, and often are wet and slippery, consider the health aspects of moving batteries in and out also. Hernias and damaged backs can be expensive to repair. Replacement options aren’t good either.
LFP is the battery chemistry for me.

[Simi 60]

Originally Posted by Cornishkiwi

Yeah not for a minute, havnt got that kind of cash [emoji1787][emoji1787]

In Australia an EVE 280 ah LFP @ 24v using A grade matched and batched cells costs considerably less than equivalent usable ah AGM

Would probably be cheaper than LA