Bow battery for bow thruster. Normal wet cell lead acid or Agm?

[CLB]

I need to replace the 10 year old bow battery. The one I originally installed was a very expensive Odyssey AGM battery that I was told would be best for the application as it was leak proof and more vibration resistant, which on a planing hulled boat sounds reasonable.

Looking at replacements I can get a like for like replacement for about £180. I could go for a red top Optima for about £140. I have also found a budget Hankook AGM for about £85. Alternatively, I could stick a quality wet cell in the locker for around £60.

Dos anyone think a wet cell battery is a bad idea in a bow application? Does anyone only use wet cell batteries in the bow and not had a problem? 10 years out of the current battery is good, but I could have bought three quality wet cell batteries for the same amount, so if they only last 3 years or so I am no worse off. What does the panel think?

 

[kashurst]

I use standard wet cells in mine - no leaks no problems

 

[Momac]

I have one of Halfords lead/acid sealed . This was due to a need to obtain a battery at short notice on a Sunday and they were open. Not the best price but not life changing.
What you should look for is a starter battery with decent CCA rating and not too fussy about amp hours.
If the battery is in an enclosed space without ventilation you should use a sealed battery.

 

[DavidJ]

I'm sure you have but check your installation. To replace mine I had to put it in sideways on so lead acid (wet) a no go'er.

 

[wipe_out]

Ours came factory fitted with AGM for the bow thruster (engine and domestic are sealed lead acid).. Apparently AGM don't "gas" like the standard lead acid making it more suited to "internal" use..

 

[Spi D]

If your use of the battery takes it belowe som 80% capacity (expectedly you will run the thruster more than a starter motor, that works for some seconds then run for 'long'), a battery that tolerate deeper disharges and will recharge from there would be my suggestion. This spells AGM so next requrerment would be the biggest you can fit, at the best price.

Was discussed lately here:
http://www.ybw.com/forums/showthread.php?471014-Battery-types-explained-in-plain-words

 

[CLB]

Thanks all. Think I am going to go with the budget AGM option. It's a small boat so the bow bounces around quite a bit and I think wet cell will have a tough time. This, plus the fact that it is only £25 more, makes it a no brainer I suppose.