What battery trickle charger are you using ?

[re-tyred]

Smart chargers are great, but not perfect. They work almost perfect on perfect batteries and will extend the life of batteries that are intermittently used.
But! once your battery starts to get a bit of age on it and has trouble coming up to full voltage they run in to problems.
A regularly used battery that is charged each time you use it and then sits for a day or so, say your car battery, will start to show signs of failing. Not cranking so good or dropping off quick when under a load without charge.
If you swap to a float charger as soon as you stop using it, it won't come up to voltage and the charger won't switch to float. If you grab your boat and tow it to the ramp you may find that in that month of lay off, by the time you get there it is completely flat, as the float charger has just kept pouring in the charge and cooked it. It pays to disconnect your float charger the day before and after a couple of hours, check the battery voltage. Nothing kills a dodgy battery faster than being on charge for a week.
This scenario is likely to cook a small float charger as well.
In 30 years of being a technical repairer in the marine electronics business I have repaired a number of expensive float chargers. There seems to be a small percentage of even the expensive ones that fail, mostly in the above scenario or cranking a motor while still connected. Yes you will get away with it many times but once in a while you will be up for a new charger. There is also a small chance of damaging the alternator if you don't have full isolation when the charger is on the batteries. By that I mean an isolation switch that disconnects power to the motor.
Charging batteries in parallel can also cause problems when the batteries get older as they each come up to float at slightly different times. If you have dual battery system without a voltage relay, isolate them and swap the charger to the other battery every week or so.
Which is the best charger? Well generally a big one that is expensive commercial grade one. Ctek, victron etc. But if you have a small battery system and a small budget don't dismiss the cheaper smart chargers that are out there. I just have a $40 8 amp smart charger on my bikes and tinny, but I do not leave it charging for weeks at a time. I usually give the bike a charge once a month for a cpl of days. The tinny I charge if I notice the voltage is not up to at least 12.8v when i get home or it drops below it while I have a long lay out like now. Again it is just on there for a few days.

[purple5ive]

Ive always isolated the battery before i plug the charger into it, same with the Trolling motor battery.

[SteveoTheTiger]

I dont have a trickle charger. I just have a cheap charger i got years ago from Kmart (i think), i dont remember the name of it but it was less than $50. I just hook it up a day or two before i am heading out and periodically if im not using the boat (usually at the start of each month). In 40 years of boating i have never had any battery issues.

I guess i should look at some of these new chargers though because mine would have to be 10 years old.

[hornet]

Smart chargers are great, but not perfect. They work almost perfect on perfect batteries and will extend the life of batteries that are intermittently used.
But! once your battery starts to get a bit of age on it and has trouble coming up to full voltage they run in to problems.
A regularly used battery that is charged each time you use it and then sits for a day or so, say your car battery, will start to show signs of failing. Not cranking so good or dropping off quick when under a load without charge.
If you swap to a float charger as soon as you stop using it, it won't come up to voltage and the charger won't switch to float. If you grab your boat and tow it to the ramp you may find that in that month of lay off, by the time you get there it is completely flat, as the float charger has just kept pouring in the charge and cooked it. It pays to disconnect your float charger the day before and after a couple of hours, check the battery voltage. Nothing kills a dodgy battery faster than being on charge for a week.
This scenario is likely to cook a small float charger as well.
In 30 years of being a technical repairer in the marine electronics business I have repaired a number of expensive float chargers. There seems to be a small percentage of even the expensive ones that fail, mostly in the above scenario or cranking a motor while still connected. Yes you will get away with it many times but once in a while you will be up for a new charger. There is also a small chance of damaging the alternator if you don't have full isolation when the charger is on the batteries. By that I mean an isolation switch that disconnects power to the motor.
Charging batteries in parallel can also cause problems when the batteries get older as they each come up to float at slightly different times. If you have dual battery system without a voltage relay, isolate them and swap the charger to the other battery every week or so.
Which is the best charger? Well generally a big one that is expensive commercial grade one. Ctek, victron etc. But if you have a small battery system and a small budget don't dismiss the cheaper smart chargers that are out there. I just have a $40 8 amp smart charger on my bikes and tinny, but I do not leave it charging for weeks at a time. I usually give the bike a charge once a month for a cpl of days. The tinny I charge if I notice the voltage is not up to at least 12.8v when i get home or it drops below it while I have a long lay out like now. Again it is just on there for a few days.

This was most helpful re-tyred and guided me to my purchase, I now have a CT-3800 Ctek 3.5 amp ( $75.95 ) , thx for the detailed reply...

AND to all the other members for their input it also helped...

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