Optima Batterys

[barnacle]

I have received a few e-mails on these batterys. There has been problems with them when used on outboards. There was a study done by a company that makes the electrical items for some outboards out there. He was the letter we received on them:
I now have some results to share with you. READ the charging instructions on the back of the battery! Even if the front of the battery says it is a STARTING/DEEP CYCLE, DO NOT USE FOR A STARTING BATTERY FOR AN OUTBOARD ENGINE. The limitations on the battery are 14.4V @12 Amps. Most Outboard charging systems will produce 14.6V - 15.8V's @6 to 40 Amps. Like anyone else would do I saw the label on the front and assumed (Yea I know)that the battery would be ok for the starting battery. Unfortunately, the battery did not agree. Everything was fine until the engine was opened up. At WOT the battery voltage went to 17.5V all at once and when the trim was engaged for a high speed turn, the down relay fused. When the up relay was engaged, the trim motor went poof. After we got back to the dock and checked the battery, that was when I noticed the small print on the back of the battery concerning charging instructions.
These will be great batteries for the trolling motor, but I cannot recommend them for starting batteries at this time. The design of glass mat batteries limits the charging rate that the battery can take. In a normal acid battery, when hydrogen bubbles form on the plates, they rise to the surface and burst. In glass mat batteries, the bubbles gradually work their way up to the top. Too much charge rate and the bubbles don't rise, they cling to the plates causing the charging system to think there is no battery there.