Re: WHAT'S A GOOD BATTERY TO BUY FOR MY OUTBOARD?
Hi Brian...<br />Just a couple of thoughts... Almost ALL batteries on the market for autos, boats, etc., are of the Lead-Acid variety, but there are two main types in use... Acid Starved, which are "sealed" with a minimal amount of acid stored in a medium, such as fiberglass matting, or in a gel, and Acid Submerged...<br /><br />Acid submerged are the one's we've all dealt with for many years... They require a watch on fluid (water) levels, to make sure the plates do not get exposed to air (oxygen) which will cause them to "oxidize", and become ineffective as battery plates.<br /><br />The Acid Starved batteries, are essentially sealed and come in two main types, "Gel-Cell", and "AGM".<br /><br />Marine batteries (both cranking AND deep-cycle for accessories) are designed for rugged (heavy vibration environments) use. In general, MOST auto batteries, with the exception of certian OEM's (such as select models of Jeeps, some HD Pick-up trucks, commercial equipment like tractors, etc.) do NOT have the plates well enough anchored to protect them from "shorting" against each other during extremes of vibration. (like boating)...<br /><br />Depending on how severe you vibration environment is (roughness of water, boat ride quality, battery mounting location, etc... all come into play here) you may want to look into the "acid starved" types of batteries, such as the Optima, and other brands of "spiral-wound" technology, and similar batteries. Several folks carry these types of batteries.<br /><br />Most folks call these "gel" batteries, but there are only a VERY few number of manufacturers of true gel cell batteries, and those gel-cells are not only VERY $pricey$. True Gel's are VERY sensitive to proper charge rates, thus typically NOT what an average boater would want to fool with, as the type of charger required to keep them under control is $$$ because it requires a temperature compensated voltage regulating circuitry.<br /><br />If these gel-cells get too little charge voltage, (usually under 13.4v), they simply will not charge, too much (typically over 14.4v), and even though they are sealed, they will "gas". When that happens, it's the same thing as letting the smoke out of your computer... Once the smoke is let out, they don't work too well...<br /><br />With all that said, THE best batteries are those that are fairly priced in your area, and fit the intended applicational environment. My personal favorites happen to be the "AGM" (Acid-Starved Glass Mat) batteries. These are ALSO "sealed-for-life" like the gel-cells, but are less sensitive to charging rates.<br /><br />There are a host of brands are out there and they ALL use nearly identical technology, so pick a dealer near you whom you can trust to help you when (NOT IF... WHEN...) you have a problem with one of them...<br /><br />Another neat thing about the AGM's is that they can be mounted in nearly ANY position, with almost no ill effects. But like ALL batteries, they will need to have at least some amount of ventilation fresh air, in the event you have a charging circuit problem that causes them to over-charge, as they will also gas, but are more tolerant of short-term charging voltage spokes that are the true gell-cells...<br /><br />Expect to pay any where from $85 -to- $150 (or perhaps a bit more for some sizes and brands) a piece for the AGM "spiral wound" type batteries, depending on size, and place purchased.<br /><br />Good Luck, Obiwan