AGM batteries..... I know,

[FabricGATOR]

So my new boat came with odyssey 34m pc1500 batteries. They are AGM and the company literature talks the world of them.

I tried to search this forum "AGM" "SUGGESTED BATTERY" "BATTERY" and I get a lot of info on everyone's electrical problems. I don't see yamaha prohibiting them on google.

Please explain why they are bad and encourage me to replace them.

I've read some of the threads about charging voltages going high, is this why they are not good service?

I apologize, I don't want to get a discussion spooled up, just please guide me to a location where I can learn.
Thank you.

Twin 150 ox66 year 2000

[rodbolt17]

run them till they wont,or they catch on fire.
they wont hurt the engines.

[RetiredGuy]

As rodbolt stated "they wont hurt the engines"

It's the other way around

The engines will destroy the batteries

Check the manufacturer's charging specifications and take a close look at what your engine charging circuit is doing. Loads of variables involved; Operating time, Temperature, Voltage, Current capacity, etc..

[RetiredGuy]

This site has some excellent data

Battery - 10 - Storage Battery Troubles

[FabricGATOR]

Thank you,
I have concerns about the statement of them "catching on fire" I would think that would be detrimental to the shine of the gelcoat finish.

Basically the rudimentary charging system deteriorates the batteries at an accelerated rate and the best choice in the future would be regular flooded lead acid batteries. With regular maintenance, inspection and service. Correct?

Thank you, a wealth of information in that link.

[RetiredGuy]

Lots of great information on Batteries is easily available

Chances of a "Fire" my guess about the same a winning the Lottery for serval hundred Million $$ - It can happen

Yes what you stated is good common sense

For me I run AGM batteries since they are far superior to regular flooded deep cycle batteries in my application, a *****ing motor. To properly charge the batteries I use a Sterling Power systems BtoB 12 to 24 charger and set the multistage charging properly for AGM batteries - works great and I expect the batteries to last at least 7 or more years

[BQUICK]

I've had a number of Optima batteries suddenly die in automotive applications. Wasn't a big issue on land. On the water it might not work out so well.....

[rodbolt17]

I have seen 3 different optima's with holes burned through the side of the case.
its why yamaha specifically states no dry cell or AGM batteries.
only wet cell non-maint free.
most of the V6 EFI,HPDI 2 and 4 stroke moters have 35 to 50 amp outputs.
max output may be achieved as low as 2000 RPM.

however its not a staged output,you get what you get until something gives.
most dry and AGM style batteries cannot handle this "hot" charge.

however you run what you wish,wont hurt the motor.