Lightweight 15-20 lb starting batteries with 45-60 Minute Reserve time

[scott reierson]

What are your guys using for lightweight race batteries in the 15-20lb range? I need some piece of mind on a good reserve time.

I'm told my Merc I6 battery ignition system probably uses maybe 5-10amps to run the ignition system. The Stator only puts out a max of 9 amps.

I'll also be using this battery in 2.4 & 2.5 Carb or EFI systems with the 16amp Stator. These are race/pleasure boat applications. No other electric loads other than the motor.

I'm looking at the $200 Braille 17lb AGM with 45 Minutes reserve time @25Ah draw. The CA looks good. Oddessy and XS have similar offerings

The $130 15.5lb Oddessy PC 680 has 24 minute reserve @ 25AH and CA looks a little low. The $260 20lb PC 950 has 60 minutes and good CA

The lower cost smaller 20-22lb lead acid stuff seems weak.

I realize my lower current draw will extend the reserve minutes longer. I've done the calculation formulas at these lower amps as I've not been able to find chart or spec data

Hoping to spend no More that $100-$200. Not looking to spend the money on the super trick stuff I see in the OB drag boats the last couple of years.

Let me know what you think

[Turtleherder]

https://www.amazon.com/Genesis-Hawke.../dp/B0002ILK68 I have had good luck with these batteries. It always has the juice to spin my v4. Light weight, can mount it anywhere and it doesn’t even lose charge over the winter. In eighteen years I only replaced it once after twelve years.

[KeninSC]

Look at group 51/51R. Range from 26 to 28lbs. Lead acid battery will work great with your non-regulated I6 charging system. (Honda Civic battery). Will also work great with your 16 amp charging systems regulated or non-regulated.

[KeninSC]

The Braille AGM works fine with a regulated charging system. If you go this route, the Braille batteries are manufactured by Deka/East Penn. Any of the same size powersports batteries from AZ/Advance/O'Reilly's that are manufactured in the good old USA are probably made by Deka/East Penn and can save you some dollars.

[KIRCHNER]

After researching the pros and cons i went with a lithium. have it for a while now, never touched it since i installed it. has never needed a charge, cranks my 225 like a top. just efi and trim. no other draw. incredible power from 2.5 lbs. so far, so good. 200$.

[scott reierson]

Thanks Turtleherder. Got the link and took a look. Checking out that option

[scott reierson]

Hey KenninSC,

Thanks for the reply. I appreciate it. Have a couple questions...Do you know if my thoughts below are correct.

I forgot about the unregulated charge amp issue. Am I correct in understanding that the SLP (sealed lead batteries) are more tolerant of absorbing a overcharge from the unregulated 9-16 amp stators once they are converted to DC by the rectifier?, and that the AGM's may get overcharged by a sustained unregulated amp input raising the charge voltage to high for to long of a period which is bad for them?

If a AGM gets overcharged voltage, does it have an internal link that cooks and opens up making them no good?

I'm sure I've been told in the past but i did not retain the knowledge

Thanks to all of you for your help. If you prefer PM replies please let me know.

Scott