TOPIC: Battery suggestions

I am hoping someone here can give me some suggestions. I am trying to reduce as much weight as possible in the back of my little 9' Superlight clone. Power comes from a 20hp Merc with electric start. The battery is in the starboard rear corner and the gas tank has a fixed holder in the center under the splash well. Relocating the fuel tank is not possible, there simply isn't room. And not many options for the battery either. Weight reduction is my best option in both cases. Changing to a plastic fuel tank will shed some pounds and possibly a smaller tank. What options do I have battery wise? Would a larger motorcycle battery work? The main function of the battery is to run the starter, no accesories, etc. to power. If I could find a small enough battery, I might be able to mount it in front of the fuel tank location, moving the weight forward towards the middle of the boat. I really need to think "outside the box" on this one. I will try what "they say can't be done" if there seems to be some logic to it. I'll try to post some pictures of the inside of my boat so you can see what I'm dealing with this weekend. I look forward to your suggestions.

Try this: www.odysseybattery.com/marine.html

Or go to NAPA and get an Optima.

Frank

Check the specifications for the outboard and see how many amps it pulls during cranking. While its unorthodox, you could find a way to mount the battery someplace forward. If you do, you might want to consider some small trickle charger to mount with it, so that you don't have to worm your way in there to charge it, or have some terminal connectors aft that you can attach jumper cables to and/or the charger.

I'll try to research an answer.

Ok here it goes....out of the box! How about 2 small batteries hooked up in parrell? Pos to pos and neg to neg. This will give you more amps but the same voltage.

I'm gonna let you & anyone else who reads this in on a little secret.

Buy a used Wheelchair battery.

Medical mobility companies that service electric wheelchairs replace the batteries on regular intervals - regardless of condition. They do this to prevent someone from being stuck on RR tracks etc., with a faulty battery.

Most sell these perfectly good batteries to battery recyclers for 5 bucks each. This is no joke.

I bought a used wheelchair battery 1 & 1/2 years ago from a battery place for 15 bucks. It was load tested and guaranteed for 30 days . Well, it's still going strong.

The battery is about the size of a large kid's lunchbox. It is sealed lead acid, so it doesn't outgass Hydrogen, and it can't spill in the boat. The plates are designed for rough service. I used it last week to jumpstart my V6 Dodge that had a completely flat battery. The little wheel chair battery hadn't been charged or used in 4 months.

How can you beat that for 15 bucks? As long as i can get them, I'll never buy another new battery for my outboard boats.

Well I'll be darned, never thought of that. I had a buddy in a wheelchair too! You're saving about what, $50 or $60 a battery and still getting a "deep cycle", I like it. What's the physical size and weight like Bruce? Comparable to regular, or smaller?

Roughly :

W = 7.5"
D = 5"
H = 6.5"

Weight is around 15 - 20 lbs

I bought stainless steel 1/4 bolts with stainless wingnuts for the posts. Hooks right up like a marine battery

Just keep in mind the cranking amps needed to turn your motor over. I keep a moderate sized motorcycle battery(which is probably similar in size and output to that wheel chair battery), fully charged and ready to go under the seat in one of my boats as a backup for starting since it has not charging system and im too lazy to use the pull rope... Its a 1957 35HP Seahorse and that battery is borderline having enough amps to turn the motor over, even after a full charge. It will do it, but not for very long and not very many times. Its kinda one of those "just incase" things...

Deep cycle batteries really arent needed unless your going to be running accessories where you potentially might be draining the battery completely. Regular starting batteries offer more cranking amps at the expense of a shorter life if they see alot of discharging.

Personally, id just go to Napa, Autozone, etc and find the smallest car battery they offer...maybe out of like a Honda Civic or other similar sized car. They are almost half the size of a standard car battery and offer more then enough juice to turn a motor over. I know the one in my fiances Civic is TINY and probably doesnt weigh more than 20-25ish pounds. If you need lighter than that, id start shedding weight elsewhere in the boat first.

Jeff

the $ 15 wheelchair battery started a 240 cubic inch V6 truck engine - and the truck engine had a dead battery still connected to it. It cranks my V 100 evinrude over just as fast as any other battery. And it can crank & crank & crank. It is far mor robust than any motorcycle battery. Not even in same league. Untill you try one yourself - I don't think you can appreciate how well these work. I never would have believed it before trying it. what do you have to lose over 15 bucks? Bottom line, don't knock it 'till you try it.

Jeff

the $ 15 wheelchair battery started a 240 cubic inch V6 truck engine - and the truck engine had a dead battery still connected to it. It cranks my V 100 evinrude over just as fast as any other battery. And it can crank & crank & crank. It is far mor robust than any motorcycle battery. Not even in same league. Untill you try one yourself - I don't think you can appreciate how well these work. I never would have believed it before trying it. what do you have to lose over 15 bucks?

a lot of hydro racers use riding type lawnmower batteries, small light and enough cranking amps