Trolling Motor Battery Charging

[Abbeysdad]

So after I realized my new/used boat had a starting battery hooked up for the trolling motor, I went to Wallmart and got the big yellow max EverStart duel deep cell. So far I'm very happy with it - used it a fair piece on the water and came back to still have it at 90% according to my Ship 'n Shore charger in test mode.

But here's the question, do you recharge your trolling motor battery after every time out regardless of how much you used it, or wait until it's at some level (like 60% or so)?
(I always want plenty of power, but want to maintain the battery for maximum use life too).

Edit: Also, my charger for deep cell has 10amp or 15amp charging with 15amp charging being significantly faster. Is 15amp (fast) charging okay for battery life?

[nofearengineer]

Originally Posted by Abbeysdad

So after I realized my new/used boat had a starting battery hooked up for the trolling motor, I went to Wallmart and got the big yellow max EverStart duel deep cell. So far I'm very happy with it - used it a fair piece on the water and came back to still have it at 90% according to my Ship 'n Shore charger in test mode.

But here's the question, do you recharge your trolling motor battery after every time out regardless of how much you used it, or wait until it's at some level (like 60% or so)?
(I always want plenty of power, but want to maintain the battery for maximum use life too).

Just because a battery is capable of being greatly discharged with few ill effects, doesn't mean it is best to do so. In a perfect world, you would never discharge it past a couple percent, just like a starting battery; i.e., charge it off of your outboard's alternator while running from spot to spot.

I do not have something like that yet. I always plug my on-board charger into the wall in the garage as soon as I get home. I would do that even if I had a charge on the run setup, because the on-board charger will maintain your battery against losses while sitting there unused.

[Abbeysdad]

But that raises another interesting point/question - the (starting) battery hooked to my system 'seems' to be charged/maintained at about 70% by the motor. Should I charge that or let it be maintained as it is?
Getting back to the previous trolling motor battery question, I was thinking that charging a battery when it tests at 90% isn't quite necessary...so then what about 85%...

I'm thinking right now I'll always charge the trolling motor battery after every use, and unless there is trouble or question, let the motor maintain the starting/system battery - ?

[nofearengineer]

Originally Posted by Abbeysdad

But that raises another interesting point/question - the (starting) battery hooked to my system 'seems' to be charged/maintained at about 70% by the motor. Should I charge that or let it be maintained as it is?
Getting back to the previous trolling motor battery question, I was thinking that charging a battery when it tests at 90% isn't quite necessary...so then what about 85%...

I'm thinking right now I'll always charge the trolling motor battery after every use, and unless there is trouble or question, let the motor maintain the starting/system battery - ?

What are you counting as 70%? A lead acid battery should be at around 12.14V when it is at 70% capacity.

Honestly, your starting battery should be at 100% (12.6V or more) after a few minutes of your outboard running, unless you've got a whole heck of a lot of electronics and a huge stereo system on your boat heh. Either way, there's a problem there. Your alternator / regulator might be bad, or the battery might need to be equalized to bring it up to the right voltage.

[MallenManson]

I throw my battery on the charger every time I come back from the lake

[remington]

I run my dead from brand new, recharge 100% then recharge after every use.

[nofearengineer]

Originally Posted by remington

I run my dead from brand new, recharge 100% then recharge after every use.

I have also heard of cycling a new deep cycle battery a couple of times when it is new like that. I'm not sure why, but some people recommend it. I can't think of any logical reason it would be beneficial to the battery.

[Abbeysdad]

I was looking in my MinnKota 50AT manual and they recommend keeping the battery fully charged - they go one to indicate that batteries not recharged within 12-24 hours of use have much shorter life spans. The later in the manual they recommend charging before each use.

[Abbeysdad]

Originally Posted by nofearengineer

I have also heard of cycling a new deep cycle battery a couple of times when it is new like that. I'm not sure why, but some people recommend it. I can't think of any logical reason it would be beneficial to the battery.

I wonder if this is a spill over from rechargeable batteries:
http://en.wikipedia.org/wiki/Memory_effect

[nofearengineer]

Originally Posted by Abbeysdad

I wonder if this is a spill over from rechargeable batteries:
http://en.wikipedia.org/wiki/Memory_effect

It could be...like one of those old wivestales that never quite go away.

The only thing is...lead acid batteries don't have memory. And the newer rechargeable batteries don't either.

[Jigger]

Originally Posted by MallenManson

I throw my battery on the charger every time I come back from the lake

Ditto...........