I own a 27 foot power boat. Is it best to have 2 deep cycle batteries or one starter and one deep cycle?

Why do people keep insisting on using deep cycle batteries for starting batteries.

As posted above and here it is again.

Starting batteries are designed to start your engine which pulls a lot of cranking amps.

Deep cycle batteries are for small current draws such as trolling motors and accessories

A starting battery is designed to take the heavy draw from starting and constant charging

A deep cycle is designed for light amperage draw.

Any reputable marine supplier will verify this

Or just keep going to Pep Boys and buy your deep cycle batteries and their advice.LOL

It does not really matter what brand the battery is but what type it is. The best batteries are AGM (almalgamated glass matt) they are high capacity, can be mounted at any angle and are good deep cycle battery's. It depends on what type of boat you have to what size you need. I sail a 47 foot yacht and it has 4 400 amp hour AGM batterys. With a solar panel and motoring a little(not more than an hour or two a day) that is pleanty of capacity to last 3 weeks whilst using the power inverter, TV, microwave, 2 fridges and all of the instruments as well as the coffee machile. AGM are the way to go. ALL MARINE BATTERYS ARE 12 VOLT. THEY ARE NOT 6 VOLTS, IF YOU CONNECT 2 TOGETHER YOU WILL GET 24 VOLTS

IT DEPENDS ON WHAT YOU ARE DOING WITH THE BATTERIES. If you are using them for a trolling motor for fishing, use a deep cycle. If all you are doing is running your boat, a regular marine battery will be fine. If you have a stereo on board, use a deep cycle. Yiou see, the term deep cycle is one that tells you the battery is usually a bit more dense in the plate area, to allow you to use the battery longer between charges. Electric trolling motors use a lot of power, so the battery needs to be strong to supply it with enough current to last a long time. You may want to install a battery isolator in your system to isolate one battery for use to power your stereo or lights while not cruising, and then be able to switch over to a "starter" battery as you called it to get the engine running. Then you can switch back and forthe between batteries to charge them properly. Any Marine outlet can help you with installation of any of there ideas...

Happy boating!

Stevo.

We have two deep cycle batteries on our MasterCraft with a toggle switch. We are able to shut the power from the batteries completely off, use just one or both at the same time. When we are cruising, we only use one but to listen to the stereo and wakeboarding...we use both. It's good to have (2) plus the switch...if one ever goes bad, you have another. Also, we carry a portable power pack if for some odd reason they both won't start but it hasn't happened. Costco carries there Kirkland brand Deep Cycle Marine batteries that are made by Optima but at a MUCH lower price. Plus, you can return them for credit if they fail early with/without a receipt.

Best? ---> Optima...

Though my Interstate Deep cycles seem to be doing just fine..

Get the same type and hook them up to a good battery switch for 2 batteries...

Make sure your on-board charger is set for the type of battery you choose

Two deep cycle batteries. Connect them together + to + and - to - will give you juice at one time. I've never heard of a "starter" battery.

paultec has got it right but i would like to add one thing.Have a battery isolator switch installed.This switch allows the engine to charge both batteries at the same time but prevent you killing the start battery by running the radio,trolling motor etc.

you need a starting battery, deep cycle batteries are designed to be charged and discharged, it is hard on them to use them for starting batteries.

just get the ones that came with the boat if you don`t no then call the boat dealer that sold you the boat.