|Topic Review (Newest First)|
|12-09-2008 08:26 PM|
Trojans are not the only choice for wet acid batts.
Interstate makes 225Ah. 6V that are pretty good also. They hold more liquid are heavier and have better construction.
I've had six of them in my Endeavour 32 for 8 years now maintained only by my AirX turbine...they lasted 8 years and I wasn't very nice to them. I bought 2 Rolls Surrette 8D's because I got them for a song at CE Beckman's.
But I was pleased with the Interstates.
And...There is no such thing as a "maintenance free" batt.
|12-09-2008 10:18 AM|
|sailingdog||BTW, Hydrogen is pretty good at escaping... Helium isn't as active and look at how it does from sealed mylar balloons. You probably don't need a whole lot of venting for a battery box...as long as the vent is at the top of the box... Hydrogen rises...fairly rapidly.|
|12-09-2008 10:15 AM|
Originally Posted by xort View Post
Vent it anywhere you like. The whole idea is just to get some air flow in there so there is no accumulation of vapor.
|12-09-2008 10:03 AM|
Originally Posted by JHJensen View Post
a. Venting out of the battery box into the under bunk area?
b. Venting out of the under bunk area into the living space?
c. Venting out of the box directly overboard?
d. Venting out of the under bunk area overboard?
e. Something else?
My boat has had batteries under the bunk since 1985, as designed by the factory. Am I about to die?
|12-09-2008 09:49 AM|
I would suggest that the problems with the current set of batteries may have been caused by a failure of one of the batteries cells which resulted in a cascade failure rather than one caused by the charger. Certainly have the charging system checked out...but recognize that batteries do fail.
I would suggest looking at the Odyssey AGM type batteries for the future as they can accept charge amperage well in excess of their rated capacity which will result in much faster charge times. The Freedom 25 can supply 125 amps and you can deliver ALL that amperage into ANY Odyssey battery. Thus with a 450 amphour bank 50% discharged and needing a 225 amp hour recharge...you could be fully recharged with the Freedom25 in two hours.
|12-09-2008 09:01 AM|
Traditional wisdom for wet-cell batteries is not to charge at more than 20% of the battery bank capacity as a maximum charging rate. You can charge at a higher rate and get away with it...but it generally isn't too good for the batteries. AGM batteries have a much higher current acceptance rate and can often be charged at closer to 50% or so of battery bank capacity.
Some of the newer technology batteries can be charged at even higher rates.
Originally Posted by Omatako View Post
|12-09-2008 04:15 AM|
Just for the record: the title of this thread ("Trojan vs AGM") is confusing as Trojan has been making AGMs themselves for several years now.
In fact, we have had 5 Trojan 27G AGMs onboard since June 2006 and have been very happy with their performance as well as their proven ability to withstand tough operating conditions here in the South Pacific.
|12-09-2008 03:23 AM|
Originally Posted by sailingdog View Post
I have only four T-105's in my house bank. I also have a Freedom 25 charger. I also have a 185 amp alt on my main engine which routinely pumps 140 amps into the house bank when it's a little soft. I can't say I've ever had an overcharge situation because of this. I monitor the whole lot via a Link 20. My batteries aren't gassing and I'm not losing a lot of water.
Most cars have a 65Ah battery driven by a 55 amp alternator. That's quite a bit more than 20%. Most are wet cells.
I always thought that the regulator decided what amperage was delivered to the batteries. Not the charger.
Am I wrong? Again?
|12-08-2008 12:00 PM|
Originally Posted by JHJensen View Post
If you over charge AGMs though, you can dehydrate the electrolyte and destroy the batteries very easily.
|12-08-2008 10:18 AM|
Batteries: Wet Cell vs AGM, Hydrogen Gas
Originally Posted by dsbentley View Post
Your battery compartment(s), no matter if you have wet cell or AGM are required to be vented. Wet cell batteries produce hydrogen gas while charging and lots of it if they are being overcharged.
AGM batteries only produce hyrodgen gas if they are being overcharged as what appears to have happened to yours. People( builders, some repair techs and those not in the know) sometimes think that because they do not produce hydrogen when all is working properly, they can be put anywhere. There are a number of cases where AGM types have been stuffed into unvented compartments and have overheated and exploded. A bad experience if you happen to be nearby or on top of them (as in under a bunk). It is ok to have them under a bunk, just make sure you have a proper ventilation system set up.
Both types of batteries have different charging requirements which your system (Link 2000) should be able to ajusted to when it is set up properly, which also includes temperrature compensation during charging.
ABYC Standard E-10 covers the requirements for proper procedures for storage batteries, including the Federal Regs. This will make your insurance company happy as well. Request that all work done on your vessel be done in accordence with ABYC Standards and applicable Fed (CFR) regs as well.
ABYC Master Tech.
Steve and SD are correct that you will get more bang for your buck with wet cells if you maintain them. On the other hand if your system is set up properly for the you will get very good service with the AGM batteries and not have to be adding water as you will have to with wet cells.
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