Optima blue top

Doryman · Posted: Thu Apr 01, 2010 3:48 pm Post subject:

I guess I have been lucky with my Optimas.

Warren

Dreamer · Posted: Thu Apr 01, 2010 10:47 pm Post subject:

We have two Optima 34M Blue Tops for start batteries and 8D Lifeline AGM's for the house. All are working as new going into their 4th Season. The boat stays plugged in when stored and the Outback Inverter/Charger keeps them topped off at all times. I'm optimistically looking for a few more years on all four!

fishinAK · Joined: 09 Mar 2010 Posts: 12

Hey thanks so much for all the replys and help guys!

So this afternoon I bought a grp 29 interstate deep cycle. It has a RC of 205 and MCA at 845. In order to get it to fit, I had to hacksaw off the neg post, then I coated it in 5200.

My plan it to use this as my house batt and maybe use to to start the ob as well. I think will also buy a smaller GRP 24 to use as backup starting battery.

So one more question. I have both batteries hooked up to a guest 2 bank 10 amp 3 stage charger. Can I run fans, radio, etc in the driveway while the battery charger is plugged in?

Thanks again for any and all help

Levitation · Posted: Fri Apr 02, 2010 8:36 am Post subject:

The real claim to fame of these gelled-electrolyte/glass-mat-separator/rolled-plate batteries is their low internal resistance...
A battery is a voltage source in SERIES with it's internal resistor...
When you short the battery terminals together (like what happens in the first split second when you hit the starter on your engine) the amount of current the battery can deliver is limited by the series resistance of the battery-cables/clamps/relay-contacts/starter-windings PLUS the series resistor inside of the battery...
Now, you can't do much about the series resistance of your starting circuit (other than keep the connections clean) but you can choose a battery with a much lower internal resistor... So, batteries like the Optima can double or triple the current flow (and the cranking/spark) because their series resistor is so much less than big flat, widely separated, plates in a flooded battery...

The down side of these technological wonders is high cost, and a nervous disposition like a thoroughbred race horse... Personally, I prefer big, dumb, placid, reliable, flooded cell batteries - except on my airplane where these light weight, gel wonders are great...

Hooked on Powell · Posted: Sun Apr 04, 2010 5:53 pm Post subject: Optima Blue Tops

Just installed a 34M Blue Top for the start battery and a D34M Blue Top for the house battery on Frequent Sea. Also have two group 31 AGMs in the house.

I've never used them before but they have a record of good performance and very long life in this neck of the woods. We'll see how they do.