Outboards - Compatible w/ Gel or AGM Batteries ?

[Jud Hamblett]

I’ve got a 115 4 stroke Mercury and am considering using a deep cycle 810 MCA Gell or AGM (absorbed glass mat)Group 27 battery from West Marine. The literature says these batteries are sensitive to overcharging. Apparently this means anything over 14.1 volts. <br /><br />My alternator spec is as follows:<br />Three phase stator coil (12 Pole) 12.0 volts, 25 amps, 300 watts (Rectified/Regulated)Rectifier/Regulator Output Peak Voltage 750 RPM 12.5-15.5v, 1500 RPM 13.0-16.0 volts, 13.0-16.0 volts<br /><br />Question(s) – Is it ok to use a gell or AGM battery with this engine? If not, is there such a thing as a non dockside 110/220 volt “smart regulator” that can be installed between the engine and battery?<br /><br />Thanks.

 

[cobra 3.0]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

What is the CCA rating for this battery? My guess is it's by far the worst choice for your set up. These batteries are designed mainly for wheel chairs, not turning over an engine.<br /><br />I suppose you have one and it costed you next to nothing?

 

[ndemge]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

AGM batteries are nice. But people usually dont' want to spring for the price.<br /><br />in my opinion, if it's got the power to crank that motor, it's not a bad setup <br /><br />I use the deep cycles sitting in my garage all the time when I need to jumpstart a car.<br /><br />still wouldn't want to havej ust one battery in my boat.

 

[18rabbit]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Xantrex makes an onboard smart regulator. It will allow proper charging of a wet, AGM or gel cell from you engine’s alternator.<br /><br /> http://www.xantrex.com/products/product.asp?did=189 <br /><br />The problem with the higher charging voltage applied to an AGM or gel battery isn’t that they can’t take the voltage, it’s that they can’t vent appropriately. They are designed to be ‘low maintenance’.<br /><br />The best value for your dollar is a wet (or flooded) battery. An even bigger bang for your buck comes with buying a high-end battery. Might cost twice as much but will last 3-times as long, if maintained. Saw a long-voyage sailboat yesterday that has had the same Serrete deep cycle batteries installed for over 10-years. If you are not one to maintain a battery, do NOT waste your money on a quality one.<br /><br />For us normal folk an excellent battery value can be had at Costco. Group 27, deep cycle 105 A/hr, 3-year warranty for less than $60. This is what I have been using the last couple years with an 115hp Johnson. Want a 2-bank system onboard? Add the group 24, dual-purpose staring battery, 85 A/hr, same warranty for less than $45.

 

[Jud Hamblett]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

All, Thanks for the input. Mercury suggests a CCA rating of between 350 to 775 CCA depending<br />on the climate where using this 115 HP outboard. The xantrex regulator looks like an item for a bolt on Alternator – I am looking for one for an outboard application. I ultimately want to install<br />two batteries, but need to decide which way to go. I do not like wet cells as the batteries are installed deep in the hull and ventilation is an issue – chlorine gas w/salt water. I like the AGM<br />but sounds like my charging system at 16 volts will fry the battery or burn up the charging system trying to charge them. Gel cells apparently have the same problem. The only battery I can find that doesn’t need air and is not sensitive to high charging rates is a sealed automotive type. This of course is not recommended for marine use. Perhaps having two (one for backup) and replacing them every couple of years will do the trick. (the boat is a 16 foot Ridgid Inflatable I use for coastal Atlantic and Mediterranean distance traveling)

 

[cobra 3.0]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Why do you say an automotive sealed battery isn't any good for marine use?

 

[18rabbit]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Balmar makes a less expensive, single stage regulator. May be what you are looking for.<br /><br />“The economy ERS regulator provides a non-adjustable 14.1-volt field to the alternator, making it an ideal, inexpensive back-up charge controller for most battery types.”<br /><br /> http://www.balmar.net/Page12-regulators.htm

 

[Jud Hamblett]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Is anyone out there using a Gel or AGM battery setup with their outboard???<br /><br />1. I checked the Balmar site, looks like those regulators are for bolt on alternators and not for outboard type charging systems. I've asked them to clarify. <br /><br />2. Regarding car batteries and Marine applications I pulled the following from an<br />excellent web site attributed below.......<br /><br />1.8. What Are the Differences Between Car, Marine Starting and Deep Cycle Batteries?<br /><br />Car batteries are specially designed with thinner (.04 inch or 1.02 mm) and more porous plates for a greater surface area to produce the high amps required to start an engine. They are engineered for up to 5,000 shallow (to 3%) discharges, which works out to over four engine starts per day. Car batteries should not be discharged below 90% State-of-Charge. They use sponge lead and expanded metal grids rather than solid lead. Marine Starting batteries are a comprise between a Car and Deep Cycle battery and are designed for starting and prolonged discharges at lower amperage that typically consumes between 20% and 50% of the battery's capacity. Motive and Stationary Deep Cycle batteries have much thicker (up to .25 inch or 6.35 mm) plates, more lead, and weight more than Car batteries the same size. They are normally discharged between 20% and 80% at lower amperage. Deep Cycle batteries will typically outlast two to ten car batteries in a deep cycle application.<br /><br />The above thanks to:<br /> http://www.uuhome.de/william.darden/carfaq7.htm#agm

 

[cobra 3.0]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

I am aware of the differences in plate sizes, etc. Your choice depends on what you will be using the battery for...so I gather you want to use your battery extensively when your engine is off? <br /><br />I have the hybrid battery(marine)and it is a maintenance free type. Is that what you consider 'sealed'?

 

[Jud Hamblett]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Cobra, Not sure what a hybrid battery is. But if it’s not a gel or AGM and is sealed AND has a Marine rating I would be very interested. Who makes it? <br /><br />I will in fact use the battery mostly for starting but really wanted the assurance of <br />a good tough marine battery(or two). The literature says a marine deep cycle that has sufficient CCA, would be the best bet for starting AND running light equipment, so that’s what I was looking for. Then I ran into all these charging issues. No gel or AGM battery can take a 16 volt charging rate. I use this RIB boat on the Atlantic and Med sides of Morocco and failure can be serious.

 

[cobra 3.0]

Re: Outboards - Compatible w/ Gel or AGM Batteries ?

Delco(GM) makes a maintenance free deep cycle marine battery. "Hybrid" is the term used loosely for a battery that has medium plates (not heavy plates like pure deep cycle batteries and not thin plates like on a car type starting battery. It's a compromise battery still giving good CCA and still good at getting depleted when running electric trolling motors.<br /><br />This is the one I use:<br /><br /> http://www.acdelco.com/html/pi_batt_voyager.htm