Batteries !

[top breamer]

hey i have got a jarvis marine water snake bow mount electric 44lb and wanted to know what amp/hour battery i need and is 12 v okay ? i am also looking at the weight factor to

cheers

[Davemmm]

I hope its not being used to push the boat in your picture.

Electrics pull more amps than what you think. I have the 44lb watersnake and I think it pulls around 40amps your best bet is getting around a 100 amp/hour. That will give you a fair bit of time and they dont weigh a ridiculous amount.

Dave

[pelican]

Go for a deep cycle and make sure you include a quality charger otherwise your battery life will suffer. As capacity rises so does lead and weight . The only exception is the optima style batteries which are compact and a little lighter overall but $$$$$.

Edited January 5, 2009 by pelican

[Davemmm]

make sure you include a quality charger otherwise your battery life will suffer.

Is there a specific deep cycle charger? What qualities should you look for?

[Squizy]

Mate

Although they are a little more expensive go for a Deep cycle gel sealed battery as they are more forgiving when it comes to vibration and when you run them flat. Mine is a 120ah deep cycle and I get two days fishing out of it running a Motorguide 54lb and a 39l waco fridge. I was recommended a heavy duty charger with an Auto function that has enough boost (14.5v) to bring the battery back from flat and the ability to trickle feed the battery between trips with an auto cut off.

If you pay a little extra and look after your battery it will last along time. Mine has been going strong now for nearly 5 yrs.

Squizy

Edited January 3, 2009 by Squizy

[pelican]

Is there a specific deep cycle charger? What qualities should you look for?

Depends on your exact battery and type. manufacturers of the better quality gel cells will actualy have a charging table on their website. Best chargers are ones that temperature compensate and change both voltage and amperage at different stages of charging and you actually load the manufactures table into the charger to achieve this. We can't afford that sort of stuff for only a single battery but make sure at a minimum you get a staged charger that will not overcharge the battery and will switch to a trickle and then a maintainance charge automatically. The solar shop guys know their chargers and batteries and are worth having a chat to and you can give them the details of your motor specs and what use you require and your budget.

Outboards are often pretty poor at battery charging at low revs unless quite new models but worth connecting to a leccy battery if you do quite long runs if not at home overnight will work. Some outboards will never charge a gel battery fully. Mixing both gel and lead acid batteries can confuse regulators on outboards and either over or undercharge both batteries and shorten their lives.

In examples I know of with forklifts and golf buggies a change to correct chargers for the batteries resulted in large % in capacity, longer life and less downtime which all save $ after a short time.

Both overcharging or undercharging batteries slowly kills them.

Deep cycles are designed to run down and recharged and are totally different to start batteries like car ones which are designed for a high initial draw down of current (CCA) and then get quickly recharged when motor is running. A start battery will die if let run down regularly ( discharge more than 30%) due to it's design.

Valve regulated Lead Acid (VRLA) can be a cheaper option as with AGM but $ buys quality and reliability with all batteries so don't go cheap as they will be a dissappointent and a decent charger will make a big difference to how long they lastsoworth the $ up front.

Edited January 5, 2009 by pelican