So which trolling motor batteries do you guys like?

[Glenn]

First off - if you have a differing viewpoint, that's fine - nothing wrong with that.  But there's no need to go after the person you disagree with either.  Let's keep it civil. It is, after all, just batteries.

Second - you guys have me confused.  I was told explicitly by my dealer to always turn off the circuit breakers before charging (I have 2: one for the TM, the other for the cranking batt.).  I have always done so without incident for over 6 years.

Also, I had a dead cranking battery once, and jumped it with my TM batteries.  Then we ran around the lake and let the engine charge it for awhile.

Now you guys are saying not to do that?  I'm not saying you're wrong, it's just that I've never heard anything to the contrary for years until now. So I'm a bit surprised. 

Then again, maybe I misunderstood.  Also note that ALL my batteries are deep cycle batteries, including my cranking battery.  So perhaps that's the difference.

[Way2slow]

Glenn,

Correct me if I'm wrong, but aren't you turning off the circuit breaker to you electrical system and not one that's disconnecting the cranking battery from the charger.  Where the problem comes in is connecting and disconnecting from the cranking battery.  The rectifier/regulator that charges the battery is always connected to the battery, turning the switch off or turning off the circuit breakers for the boat, does not disconnect it.   Any time you connect something of a different potential (voltage) or something that's going to place a load on the battery, there is always going to be an arc.  The peak voltage spike caused by this arc can be several hundred volts.  As I mentioned, the capacitor  affect of the battery will normally asorb this, but when the planets line up just right and the moon phase is right, that might not happen and that voltage plays havoc on your engine electronics.  Usually it get the reg/rec at about $300 but can get into the ECM.   You may connect jumper cables to it a dozen times and not bother a thing, but the 13th time and a few days later you find it's not charging, think back to when connected/disconnected the battery or jumper cables.   

The problem with using the motor to charge your battery is that can burn out the stator or reg/rec.  The charging system in outboards is not very robust and is basically designed to replace what you used cranking the motor and running the electronics.  Normally when someone has to jump a battery off, it's because it's no good.  A bad battery usually will not charge to full potential but the charging system is going to keep on cranking power into it trying.  It's not long before it finally overheats and again, the stator or reg/rec burns out.  The charging system burning out because of a bad battery is very common in automobiles also.  A bad battery can make just about any charging system to go up in smoke.

I know I came on a little strong with my rebutal of the battery post but sooo many times I see people posting on here how you should run a deep cycle battery completely down and that's just totally wrong and causes damage to the battery.  Also those that say it's best to charge one at 2 amps, that's not enough.  Approx 10% of the batteries rated capacity is the recommended  charge current.  For a group 24 you can figure approx 80ah, group 27 105Ah and 30/31 120Ah.  So, you would use 8 amps, 10 amps or 12 amps to charge them.   Then you have somebody that says run it all the way down, and then crank a massive amount of charge current into it.  That's a double whammy of being wrong.

Discharged to 50% and recharged, you can get 400 - 500 cycles, (days of fishing) out of most good grades of deep cycle batteries and the battery is properly maintained.  Improper use and charging practices, you may only get one season out of the same style battery.  It's usually not the battery that dies, it's the owner that destroys it long before it's normal life expectancy.

[K_Mac]

I am like Long mike in that I don't know a lot about fishing. I also don't know much about batteries and charging systems. What I do know is that when I bought new electronics for my boat, I called Lowrance and talked to them about how to correctly power their units and what to avoid. They told me that running my units off the cranking battery was fine, and that charging, whether by the motor or an on-board charger was not going to damage the electronics. I asked about switching or disconnecting and was told it was not necessary.

[Glenn]

Yep, I'm talking about the breaker between the batteries and the boat, not between the batteries and the charger (I don't think there is one anyway).

And that battery that needed jumping? There was nothing wrong with it. It was brand new, I just drained with my stereo.  Oops!

So if I have a series 29 deep cycle marine battery, you're saying charge it at 15amps?  That seems high, mainly because I've heard numerous times the phrase "charge it like you use it" meaning, if you drain it slowly, charge it slowly.

[scbassin]

I have never seen a circuit breaker between the charger & batteries either but that does not mean that some could not have one. What I have seen is a Perko switch(off & on) on the hot lead between the engine & battery. It is used to protect the electronics in the engine during a charge. It's turned off before hooking up your charger. Maybe that is what was meant.

It's not a good idea to to jump a battery it could play hell with your electronics or worse if it was shorted & gassing a spark from the jumper & the battery could blow the top off the battery. This goes for your car also. Now in the real world most of us do it or have done it. I would have to be hard pressed to do now though. Engine electronics are to expensive now a days.

Glenn it is not a good idea to use a deep cycle battery for a cranking battery. They are designed to be deep cycled & not top cycled. That will shorten the life of that battery.

I have never heard that saying, but as a battery discharges it sulfates & when you get back you want to reverse that process asap because the sulfation is what shortens the life of your battery (as it hardens on the plates it lowers the capacity of the battery). I use the 4 bank 15 amp charger to get this as soon as possible. You never get all the sulfation off the plates but the quicker you get to it & get it done the more you get. As a battery is charging it is taking less amperage as it comes up. (If you are charging 1 battery you notice your meter is decreasing as your battery charges). Your cranking battery usually will finish 1st. because it not as discharge as the T/M batteries with my charger those 15 amps will have switched as needed therefore getting the charge over quicker.

[brgbassmaster]

Interstate batteries all the way.

[Glenn]

Thanks for the info.  It makes sense.

I have a 4-bank, 15amp onboard charger, so I guess I'm fine.

The breaker shuts off all power to the boat, including the engine. 

I have a deep-cycle battery for the cranking battery because the stereo will drain a normal cranking battery during the course of the day.  That's how I drained the original cranking battery, and nearly drained it several times after that until I made the switch.  I'll drain it down during the course of the day just like a normal trolling motor battery. Since I use the stereo every time I go out, a deep-cycle battery is the only way to go for me.  Your mileage may vary.   

[Way2slow]

Most so called deep cycle batteries are not truely deep cycle, the are about 85% deep cycle and 15% cranking.  The will actaully have more cranking amps than many of the straight cranking batteries.  If a battery is a pure deep cycle, it will usually only have the AmpHour capacity on the label.  If it have CCA, it's intended to be used as a cranking battery also.  The big difference is they will only deliver that CCA for several seconds, which is more than enough to start most motors.  If it's a hard to start motor, then they can get you in trouble by making the motor even harder to start or not start at all because they don't have the reserve CCA to maintain full voltage while the starter is spinning.

AGM TM batteries will give you more CCA than almost any straight flooded cell cranking battery made to fit in the boat.

Glenn, there is no way you could ever fish with me.  I don't even listen to the radio in my vehicle and I dang sure ain't gonna listen to one while fishing.  If a person turned on a radio in my boat, it would be a toss up on what hit the water first, them or their radio.

[Glenn]

I use it to listen to NASCAR.