battery help for newbie

[BRANDONG1944]

Hey guys, I have a question. I am new to the boat fishing world and recently bought a 2007 bass tracker pro crappie 175. The boat has a 50 hp mercury 2 stroke with oil injection. The boat has a 46 lb thrust motorguide trolling motor. When I purchased the boat the previous owner took the deep cycle battery out and left the cranking battery.

My question is a two part question

part 1. What should I look for in a battery? I am completely dumb about this, I've been doing some research but I am still lost, please help lol.

Part 2. When I have bought said battery I plan on going on multi day fishing trips (my father in law owns a house boat). Can I charge battery after the trip or does it need to be charged every evening. I am not asking will the battery run all day but instead will it hurt the battery to use half the battery one day, let it sit over night and then use the rest the second day, then charge it when I get home?

Thanks for any and all help guys.

 

[alldodge]

Re: battery help for newbie

Starting batteries provide the most cold cranking amps (CCA) for starting but can not be drained below 60 to 70 % without possiably damaging the battery. They come in various sizes but all use CCA as their measure (exp: 1000 CCA). Deep cycle batteries provide less CCA then starting batteries and are mainly used for items not used to start engines. Deep cyle batt can be drained to very low levels without damaging the batt. Deep cycle batt also have more reserve capacity then starters and therefore will power a trolling motor longer. They can be fuuly charged and used and left allone until recharged at a later date. You need to keep the charge up on them more so during winter because a week batt can freeze. Most deep cycle batt you will find today are a cross between deep and starting which are called dual purpose or DP batt. They provide a little more amps and a little less reserve capacity.

 

[ondarvr]

Re: battery help for newbie

Most deep cycle batt you will find today are a cross between deep and starting which are called dual purpose or DP batt. They provide a little more amps and a little less reserve capacity.

Deep cycles are deep cycles, dual purpose are dual purpose, most deep cycles today are not dual purpose. You want a true deep cycle battery. The bigger the battery the more run time you will get out of it, look at the amp hour rating and get the biggest one that will fit, or you can afford.

For the longest life a battery should be recharged as soon as possible, this doesn't mean waiting a day will destroy it, only that it's not the best for it. Don't make it a normal practice and you will be fine.

 

[alldodge]

Re: battery help for newbie

Deep cycles are deep cycles, dual purpose are dual purpose, most deep cycles today are not dual purpose.

Sounds pretty much like what I said only difference is in the opinion of, your most are deep and mine most are dual

Cheers

 

[BRANDONG1944]

Re: battery help for newbie

I understand that I need a deep cycle battery but what should I look for as far as ah, cranking amps, and reserve time?

 

[alldodge]

Re: battery help for newbie

I would suggest a group 27 size and find the most ah you can find. The cost will be approxamently the same give or take some. If you think your going to use the heck out of it go to a group 31. The specs on a typical group 31 is 115 AH with 675 CCA, and group 27 is 105 AH and 575 CCA. You can go up from there just depends on how much you need. I still suggest group 27 because if all else fails to deliver what you want just put another in parrell.

 

[ondarvr]

Re: battery help for newbie

Sounds pretty much like what I said only difference is in the opinion of, your most are deep and mine most are dual

Cheers

I only point this out because people will search these threads in the future and find a post like this and it will give them totally inaccurate information, plus confuse them.

This what you said ?Most deep cycle batt you will find today are a cross between deep and starting which are called dual purpose or DP batt? this is not even remotely accurate.

Many places market dual purpose batteries as "marine batteries", but that is sort of misleading, because Marine only means it is built a little tougher to hold up the pounding, not that its dual purpose. There are marine starting batteries, marine dual purpose batteries and marine deep cycle batteries. I have never seen a company market a dual purpose battery as a deep cycle battery, some sales people will try to sell you one, but if you read the info it will tell the story.

 

[alldodge]

Re: battery help for newbie

give them totally inaccurate information

Tried to pm but I'll just say
All the best to you and yours and I hope this has been settled to your satisfaction sir.

 

[ondarvr]

Re: battery help for newbie

Sorry, I didn't mean to come across that harsh, I just didn't understand that comment.

Emptied the PM in box too.

 

[UncleWillie]

Re: battery help for newbie

I understand that I need a deep cycle battery but what should I look for as far as ah, cranking amps, and reserve time?

You are looking for a Deep Cycle Battery, not a starting battery so cranking amps are irrelevant.

Cranking Amps (CA/CCA) is a measure of how many amps the Battery can deliver for 30 seconds.
Reserve Capacity (RC) is how many minutes the Battery will supply 25 AMPs.

Amp Hours (AH) are how much power the Battery will supply if discharged in 20 hours.
The AH Spec tends to overestimate real world use because of the slow discharge rate.
It is more relevant to a lighting situation than a Trolling Situation.

Reserve Capacity x 25 amps / 60 Minutes = Amp hours.
Example; 100min RC = 41.7 AH ... This same Battery may have a 75 Amp Hour rating at 3.75 Amps for the 20 hours.

More is Always Better and also Larger and Heavier.

A very loose rule of thumb is, a Trolling motor will use 1 AMP per pound of thrust at 12 Volts.
A 100 AH Battery, Powering a 50# Trolling Motor at FULL Throttle, will last about 2 hours.

Your experience will vary.

 

[BRANDONG1944]

Re: battery help for newbie

Thanks guys, I bought a Napa special. Thanks for all your help.