Merc opti battery question

[618vs]

my mechanic has told me that I am using the wrong battery for my optimax I have been running a starting deep cycle combo in my boat he has said to only use a marine starting battery . However i run all my electronics as well hds units live wells etc I have emailed merc and they have said that my mechanic is right . Merc has told me that Werecommend a starting battery for the Optimax as the automotive style alternatorproduces charging voltages a deep cycle or multi-purpose battery can notaccept. If all the charge is not accepted by the battery at once,like with a starting battery, permanent damage to the Optimax chargingsystem can occur, possibly resulting in a failed PCM($1930). I only have room for I battery for the main motor so I have know idea as what to get what do you guys run for your opti motors that will do both jobs any help would be welcome I have also been on many battery sites but am not sure what battery i should run
Thanks

[PartyTaco]

You're going to get a lot of different opinions on this subject and I've tried nearly all of them.

I've used Optimas, Dekas, Interstates, Trojans, Sears, and Everstarts.

IMO the Odyssey group 31 PC2150 tops them all.

I'm running 3 big touch screen units, di/si transducer, sonic hub, speakers, dual 10' blades, etc and it never has a problem spinning over the opti when it's time to go....

[flranger]

The manufacturer is telling you what the motor wants. They are also telling you what could happen if you don't give it what it wants.

My recommendation is either follow the manufacturers recommendation, or if you don't, then don't bitch when something goes wrong. It's that simple. Motors are really expensive so on my new Optimax (on a prior boat) I bit the bullet and found a way to add the battery. I had the same concerns you have with space but figured it out. The reason it was tight is I was running a 36 volt setup on an 18' boat so the fourth battery was an issue.

[jbh3]

I've run dual purpose group 31 AGM's on 3 different 225 Optimax's for cranking/accessories over the last dozen years or so. They are THE way to go, IMO. The one I'm running now is the Odyssey PC2150. It (and it's equivalent Diehard PM1) is a HOSS of a battery. Check out the "recommended batteries" section in the Optimax sticky post over in the Merc 3 liter board. Whatever you run, keep it fully charged. Good luck with yours.

[CatFan]

the automotive style alternatorproduces charging voltages a deep cycle or multi-purpose battery can notaccept. If all the charge is not accepted by the battery at once,like with a starting battery, permanent damage to the Optimax chargingsystem can occur, possibly resulting in a failed PCM($1930).

No. Alternators generate charge as determined by the battery and the load on the electrical system. Every battery automatically accepts all of the charge from the alternator because it is the battery that controls how much power the alternator produces.

Though there are fairly minor chemistry differences in some deep-cycle batteries, the main difference between them and starting batteries is how thick the plates are. Deep-cycles have thicker plates so they last longer when being deeply discharged. Starting batteries have a lot of plates so they can produce a lot of current quickly to crank a motor. Starting battery plates are thin so they can fit more in the battery.

Most batteries are a compromise somewhere between producing fast power and tolerating deep discharges.

There is no electrical difference in charging a deep-cycle or a starting battery other than how you use the battery. A deep-cycle works fine as a starting battery as long as it meets the engine CCA requirements. Mercury recommends 135 minute RC and 800CCA for Optis.

Check out http://www.bbcboards.net/mercury-3-l...quirement.html

[SeanH]

No. Alternators generate charge as determined by the battery and the load on the electrical system. Every battery automatically accepts all of the charge from the alternator because it is the battery that controls how much power the alternator produces.

Though there are fairly minor chemistry differences in some deep-cycle batteries, the main difference between them and starting batteries is how thick the plates are. Deep-cycles have thicker plates so they last longer when being deeply discharged. Starting batteries have a lot of plates so they can produce a lot of current quickly to crank a motor. Starting battery plates are thin so they can fit more in the battery.

Most batteries are a compromise somewhere between producing fast power and tolerating deep discharges.



There is no electrical difference in charging a deep-cycle or a starting battery other than how you use the battery. A deep-cycle works fine as a starting battery as long as it meets the engine CCA requirements. Mercury recommends 135 minute RC and 800CCA for Optis.

Check out http://www.bbcboards.net/mercury-3-l...quirement.html

Phenomenal Explanation!

[Coke]

No. Alternators generate charge as determined by the battery and the load on the electrical system. Every battery automatically accepts all of the charge from the alternator because it is the battery that controls how much power the alternator produces.

Though there are fairly minor chemistry differences in some deep-cycle batteries, the main difference between them and starting batteries is how thick the plates are. Deep-cycles have thicker plates so they last longer when being deeply discharged. Starting batteries have a lot of plates so they can produce a lot of current quickly to crank a motor. Starting battery plates are thin so they can fit more in the battery.

Most batteries are a compromise somewhere between producing fast power and tolerating deep discharges.

There is no electrical difference in charging a deep-cycle or a starting battery other than how you use the battery. A deep-cycle works fine as a starting battery as long as it meets the engine CCA requirements. Mercury recommends 135 minute RC and 800CCA for Optis.

Check out http://www.bbcboards.net/mercury-3-l...quirement.html

I thought the Optimax required 1000 CCA ?

[618vs]

do you have to use a different battery charger for agm verse acid type

[jbh3]

do you have to use a different battery charger for agm verse acid type

The Dual Pro "Professional Series" (15 amps per bank) chargers have worked fine for me. Other brands probably will do the job as well. I believe Odyssey has a chart on their site of chargers they consider suitable for their batteries.

Bro' Coke, the Optimax spec is for 1000 MCA's - Marine Cranking Amps. If you do find one with 1000 CCA's, you'll have the MCA's covered, for sure. If you're running any accessories at all off your cranking battery, you will want a battery rated to exceed the 1000 MCA number with a high number for Reserve Capacity as well. That's why the big Diehard and Odyssey is pretty popular in this application.

[EuropeanAM]

No. Alternators generate charge as determined by the battery and the load on the electrical system. Every battery automatically accepts all of the charge from the alternator because it is the battery that controls how much power the alternator produces.

Though there are fairly minor chemistry differences in some deep-cycle batteries, the main difference between them and starting batteries is how thick the plates are. Deep-cycles have thicker plates so they last longer when being deeply discharged. Starting batteries have a lot of plates so they can produce a lot of current quickly to crank a motor. Starting battery plates are thin so they can fit more in the battery.

Most batteries are a compromise somewhere between producing fast power and tolerating deep discharges.

There is no electrical difference in charging a deep-cycle or a starting battery other than how you use the battery. A deep-cycle works fine as a starting battery as long as it meets the engine CCA requirements. Mercury recommends 135 minute RC and 800CCA for Optis.

Check out http://www.bbcboards.net/mercury-3-l...quirement.html

Actually, the ALTERNATOR (via it's voltage regulator) is what controls how much output the alternator produces. This is based on battery voltage, so the battery does play a significant role (but doesn't actually control charging current itself).

Deep cycle batteries are not recommended for Optimax engines. A Cranking Battery (or a dual-purpose battery) is recommended.

Battery recommendations are for the ENGINE ALONE, and do not take into account the electronics in or on your boat. So- if you're running 2 or more graphs, down/side imaging, pumps, and perhaps some lights, you will need SIGNIFICANTLY more battery capacity than the MINIMUM SPECIFICATION (the MINIMUM for the Engine ALONE is 800 CCA or 1000 MCA).

Don't just plug the minimum spec battery in there and expect to be able to fish with two graphs and livewells running for several hours.... as your battery will be WELL below the minimum spec when you go to start the engine.

Definitely check out the post: http://www.bbcboards.net/mercury-3-l...quirement.html

[Wildjig68]

IMO the Odyssey group 31 PC2150 tops them all.

+1