Battery Management Venture 23

[pflash]

When I purchased our 23, it came with two Group 27 dual purpose (crank/deep cycle) batteries of slightly different amp hrs and a battery switch labeled: off, one, both. It's time to buy new batteries and my tech guy where I store the boat off-season suggests one start and one deep cycle battery and a new switch with the more common layout: off, one, two, both. Any suggestions?

Second question, would the Guest 2621A charger work with AGM batteries? Thanks.

 

[Will-C]

We used two dual purpose Deep Cycle group 27 Interstate Acid flooded batteries on our 23' Venture as setup by Wefings.. We had a manual four position battery switch as I wanted simple. On 1, On two, both, and off. We used those batteries for close to five years. We later changed to Cabela's AGM type batteries and switched to a Charles brand of charger that had switch positions for flooded, gel, or AGM's set on AGM. I did not think the AGM's held up that well for what ever reason. I think one of the issues on our C-Dory was pairing a Yamaha engine with the AGM's. Maybe the manual battery switch instead of a Blue Seas automatic charging regulator had something to do with it. Some say the charging rate of our vintage Yamaha has a poor effect on AGM's.. My vote would be to try Wal-Mart flooded batteries as the were right around a 100 dollars and had a decent warranty. On the Tugnut site the Wally world batteries got good reviews as some spoke of poor AGM battery life. R-27 tugs without generators use 1500 watt inverters for 120 volts when not connected to shore power. which I think are hard on batteries.
Our new boat came with four AGM batteries from new and after three years are going strong. I don't use an inverter except a small 400 watt unit that powers a laptop for navigation. We have a generator for use if need be while on the hook. I will switch to the flooded type Wal-Marts when the AGM's give up the ghost. I have easy access to view acid levels and to be able to add distilled water if need be on the new boat. Not so on our previous Venture. The switches for battery settings were on the back of the charger we switched to. Maybe look up your model of Guest charger online to see if it has a switch seeting for AGM's
D.D.

 

[hardee]

On a 22 Cruiser, I have one battery in each lazerette. Both batteries are Group 29's and fit into the hatches with considerable shoehorn effect, but they fit, and are both deep cycle, wet plate, Interstates. They both work for starting and house. Much cheaper than AGM, and last 5-6 years between changes. When parked I keep them on "Battery MINDer" chargers that keep them healthy.

From what I have heard, the AGM's just aren't worth the $$$, the replacement cycle is not that far off mine and I don't have to have a special charger.

Harvey
SleepyC :moon

 

[thataway]

Reasons to get AGM: Low self discharge (if you leave the boat without any charging source for long timeI), If you want to put the batteries inside the cabin (no off gassing in most circumstances), If you need to put the batteries on their sides or ends, If you cannot inspect the batteries regularly to check the electrolyte levels, if you need to do a rapid recharge (as we do cranking in 30+ amps) for our reefer/freezer.

We use AGM (Sam's Club "Duracel" --made by East Penn--same ad Deka).

What kills batteries: Over charging, taking below 50% discharge (12.2 volts resting state), not checking the electrolyte, storing when not fully charged. People generally abuse batteries. Also not fully charging the battery--that is just relying on the engine "alternator"--and not topping them off after the run.

I feel that identical batteries are best. (Same age, same size, same specs, same manufacturer). The combo "deep cycle, starting" are fine. So is any AGM. Most of our engines will start fine on the "deep cycle" (they are not truly deep cycle batteries) sold in most marine and big box stores.

I like to have the combiner, so that when the engine start battery is charged, the charge then goes to both batteries. This gets away from having to switch to "all" after the engine has started. I also put my electronics on the "house" battery, so that it avoids spikes and low voltage associated with engine starts.

The Off, both, 1 / 2 battery switch is certainly the most versatile, and I feel makes more sense than other combination battery switches.

The Guest chargers which come with our boats are made to top off the batteries. I have had every one I owned fail in a few years. There are far better chargers, Some of the best are Blue Seas, MasterVolt, Victron. Along with a good smart charger, it is important to monitor the use of the house battery. Once can sue the Victron 702, the Balmar Smart battery monitor, the Xantrex "Link" or one of the cheap ones (about $15) which I just just for my freezer battery. The best is the Balmar, then the Victron. This lets you know the true state of charge and use of the batteries at all times.

 

[gulfcoast john]

Agree with Bob, esp that Guest chargers are not robust or best.
My OEM cheap Guest charger killed 3 expensive Group 31's via poor charging in under 36 months...penny wise, but pound foolish.
My replacement Blue Seas PS12 40a is not cheap, but bullet-proof and with unique ability to individually move each of 3 batteries into 'FLOAT' mode. And charge output can be dialed down to any custom amp value if you're on a 20amp pedestal. US-based superb customer support right there in Bellingham and a true 5 year warranty.
Happy hunting finding the best solution for you!
John

 

[Discovery]

We had 4 AGM's when the boat was built in Dec. of 2005. 2006 TomCat 255. They lasted less than two years. Our charger is a Dual Pro, dual 15 Amp. smart charger. I went to flooded cells when the AGM's died. I think from Walmart. I have two group 31's for the house (stb sid) and three group 27's for the Norold ref, and a Waeco fridge/freezer (port side). The five batteries are now 9 or 10 years old and still charge to a resting state of 12.8+ volts.

The best thing to do for long battery life is to buy a quality charger. Junk the Guest Chargers that come from the factory. A good charger will run about $250, but will save hundreds of dollars in batteries you won't have to buy over time. I always have the charger plugged in when not on the water.

We do have 200 watts of solar on the boat roof, and I have also wired the boat so that it charges from the truck as we tow.

I had the same type Dual Pro charger on a 17' Tracker that I bought in 2002. Two Interstate 12V batteries. I sold the Tracker in 2013 and I was still using the same two batteries when it sold. Same story, I always had it plugged in when not on the water.

 

[NewMoon]

What kills batteries: Over charging, taking below 50% discharge (12.2 volts resting state), not checking the electrolyte, storing when not fully charged. People generally abuse batteries. Also not fully charging the battery--that is just relying on the engine "alternator"--and not topping them off after the run.

I've used AGM's for both house and starting banks on New Moon for 14-15 years. First set of house AGM's (Deka g31) lasted 11 years, first set of starters (Optima blue-top 34M) lasted 7 years. In my Cummins diesel truck Optima red-top 34's lasted 10 years.

A number of folks who go with AGM's are disappointed with their longevity. The main reason this happens: Frequently not fully recharging them after use. AGM's do not like this, and tend to get sulfated if treated this way.

AGM's used primarily for starting (as in my truck) don't get discharged very far, and are quickly and easily brought back close to full charge. When they're used for house loads, they get down further, and need to be brought back to full or nearly full charge.

New Moon has a good charging system (Balmar alternator and external regulator, and an amp-hour monitor to keep track of battery condition). We typically traveled long enough most days on the water to recharge thoroughly, and the AGM's were happy.

AGM's are great for many reasons, but you need to charge them the way they need to be charged. To go with these expensive batts (if you're using them for house) I would recommend an AH meter.

 

[localboy]

This has been one issue I've improved on. Hopefully, the money spent will allow us to enjoy our experiences and our batteries will last longer. I've just installed a SmartGauge along with a Mini Add-A-Battery kit and up-sized to a group 31 house and a group 27 start. Time will tell.