Complete Battery Bank and Charger Failure

[CHM]

I just recently upgraded the electronics on my 43' Bene and was informed the charger failed (original to the boat - 24 yrs old) and 2 of 4 T-105 batteries had shorted cells. My initial reaction was frustration and some anger. I bought this boat about a year ago and this was an unexpected expense as the battery bank appeared recent. The charger failure wasn't completely surprising. Then I realized that I am at fault for the issue for not properly maintaining the batteries! I live several hundred miles away from the marina and have to rely on others for maintenance. I suspect the batteries were low on electrolyte at some point, or the malfunctioning charger contributed. In any case, I plan to replace the T-105 with AGM equivalents and will go with a Xantrex Truecharge 2 charger. I also have a wind generator in the system to help keep the batteries charged. I have an AGM in my 1975 Honda motorcycle which has been perfect for 7 years and is still going strong. The upfront cost for AGMs is significant - any thoughts, suggestions, or experience? Thanks

[Therapy]

I was glad to have AGMs when I had my Gemini because there was no access to the batteries except removal.

Flooded would have been a ROYAL PAIN.

[DeepFrz]

Before you buy the AGMs read Maine Sail's articles about them. Also wet cell batteries with water miser vent caps should make it possible to go the winter without adding water.

[sailinglegend]

Originally Posted by CHM

......I have an AGM in my 1975 Honda motorcycle which has been perfect for 7 years and is still going strong. The upfront cost for AGMs is significant - any thoughts, suggestions, or experience? Thanks

Beware - not all AGMs are the same.

AGMs are not so easy to source and there are only a few designed for marine use, but they are now becoming more popular. The problem is that not all AGMs are deep cycle, many cheap ones are designed for Telecoms or Solar standby use, so check very carefully with the manufacturer. Also not all brands are made the same way so may not offer the main advantage of charging much faster than other batteries, so potential new buyers are often confused. You may need to upgrade your Alternator and Shorepower chargers to take full advantage of the AGMs fast charge. Our Lifelines are now in their 8th year, and they are the only sealed batteries that can be equalized.

For much more detail on Flooded versus Gel versus AGM:

Deep Cycle Battery FAQ

Also check out the 35 page Lifeline AGM user manual which is a fair appraisal of the different technologies.

http://www.lifelinebatteries.com/manual.pdf

[goboatingnow]

I am not a fan of AGMs on boats, AGMs have many features, most of which ( low self discharge, high charge acceptance and sealed) are not really useful on a boat. Many people seem to think that AGM = deep discharge and of course nothing could be further from the truth.

If your charging system is boiling open LAs it will also damage AGMs, which are actually more sensitive to faulty charge regimes.

Remember, I have a cheap sealed LA in my car for the last 6 years, its going strong too, but thats means nothing if you understand how a car treats a battery.

AGMs are not a "better" LA battery , just a different one for different applications.

[ranger58sb]

We switched to AGMs; the oldest AGM bank is now finishing its 7th season, still holding at 12.6v when fully charged. In our case, the decision to switch was mostly driven by how much of an access pain it is in our installation to service flooded batteries.

Happens ours are Odyssey PC2150s, which I believe are the same as the Sears Platinum Plus marine Group 31s, and I've been pleased with their performance. These happen to offer a relatively high CCA (which you probably won't need), and at the same time decent amp-hours and discharge cycles. One nifty AGM feature is that I don't have to charge the batteries at any time over the winter, in the occasional years when we're out on the hard.

My short list at the time came down to Odyssey or Lifeline (didn't know about the Sears option, then). The Sears option sometimes offers better pricing simply because shipping (to a local store) is already factored in, and sometimes they even have sales.

-Chris

[sailinglegend]

Originally Posted by goboatingnow

I am not a fan of AGMs on boats, AGMs have many features, most of which ( low self discharge, high charge acceptance and sealed) are not really useful on a boat....

This and many of your other posts have missed the main advantage of AGMs - especially Lifeline - is that they have a high charge efficiency, which is not the same as a high charge acceptance. Yes a 100 Ah lifeline AGM can take a 500 amps inrush current = high charge acceptance. This will speed up its charging rate, but as you say for most people that is not much help to them. Its high charge efficiency however is its best feature = 98%, because this means AGMs will charge 20-30% faster than other batteries, that means 20-30% less engine/genny run time, or 20-30% less solar panels needed! This is because it will only take 102 Ah to put 100 Ah back into the battery, whilst a flooded wet lead acid may take 125 Ah to put 100 Ah back into the battery. Add to this the high charge acceptance rate and a 100 Ah Lifeline AGM will easily accept 100 amps at around a 50% discharge, whilst a LA battery will only accept about 25 amps. This is why you need as large an alternator and shorepower charger as possible to take advantage of AGMs.

Originally Posted by goboatingnow

..........Many people seem to think that AGM = deep discharge and of course nothing could be further from the truth.

I don't know where you get this idea from! The problem is that not all AGMs are fhe same, so not ALL AGMs are deep cycle, many cheap ones are designed for Telecoms or Solar standby use, so check very carefully with the manufacturer, don't just believe what you read on this forum. Also not all brands are made the same way so may not offer the main advantage of charging much faster than other batteries, so potential new buyers are often confused.

I would be very interested to hear from non-Lifeline users about the charge rates claimed by their manufacturers.

[Rapanui]

I would think that if the charger is 24 years old then it seems likely to me that it is not a modern 4 stage charger and hence has probably overcharged the batteries causing your problems.

It also seems from your post that the charger has been left on for long periods while the boat is unattended. If so, there are 2 points:
1) Electronics can and does go wrong and it will not need long to ruin a set of batteries.
2) The charge regime for continuous float charging ('wintering' setting on my Crystec charger) is a considerably lower voltage.
Either could have caused your problems

Far better is not to leave the charger on for long periods and either once a month power up the charger for a day or get a small solar panel and place it inside in a window that sees some sun and let it trickle charge to combat the batteries' self discharge but will not be able to boil the battery dry.

[CHM]

Thanks for all the replies and suggestions. I didn't mean to duplicate agm vs flooded debate as I have seen in other posts, but am making the switch due to personal logistics. In response to some of your posts: the old charger was the original Issue from Beneteau, and it does have smart charging capability, but is not of current improved technology. The boat has been on the hard and only intermittently connected to shore power. Much of the "topping up" has been via the wind generator (which I also need to check for proper controller function). The new battery bank replace 4 T-105s with US AGM 2000s. The total amp hours will be approximately equivalent at 420 aH vs 440 with the old bank. These new batteries were recommended by the felllow working on the boat. He does marine electrical work full-time, so i am trusting his recommendation. His pricing was right on with the internet. Although I have read some mixed reviews on the Xantrex chargers, I am going with one - again per his recommendation. At the end of the day, it will be close to $2k which I was not planning on now. But, thats life. The boat goes in the water finally the week after Thanksgiving if Sandy doesn't change my plans in the next day or so.

[Rapanui]

It does seem worth checking the wind generator cannot overcharge the batteries. Personally, when the boat is unattended for long periods, I would have nothing charging the batteries that can cook the batteries even under fault conditions. Having had a battery cook so that it was smoking hot while sailing the boat, the potential consequences if unattended are horrible. Thats why I suggested a small solar panel to negate battery self discharge but cannot cook the batteries.

[BadKitty]

In my experience - you would do well to replace your charger with something other than Xantrex. I would not buy anything else Xantrex with the experience I've had and comments from others.

[svinshallah]

I would second the opinion about NOT replacing your battery charger with Xantrex. I've helped lots of people here in Panama having Xantrex problems and the company is completely unhelpful.
Rick
SV Inshallah

[Caribsailors]

I'll third the opinion about NOT replacing your battery charger with Xantrex!! It smoked a 600AH AGM bank, before they smoked themselves......twice!! Zero support.
I replaced it with a Tripplite Inverter/Charger and has run flawlessly