deep cycle chargers- what amp ?

[Cheers]

Looking for info on what size charger to get . I thought that with deep cycle you needed 10 amp minimum but now I am confused . If the time required to charge is not a limiting factor what amp charge is best ?

[Esox_Magnum]

I run a 2 bank 10 amp, I fish almost daily and even after coming in late and leaving early next morning my batteries are always charged. Make sure whatever you get has a float and maintain feature.

[BobT]

In the research I've done, what I've learned is as follows.

The best charger to use is one that uses smart technology and employs a minimum of three charging phases, namely "boost", "absorption", and "float". In the boost stage the battery is allowed to draw full power to bring it quickly back to a minimum charge percentage. Once it reaches this setting the charger begins to limit the voltage without concern for current draw so that the battery is topped off. Once it reaches this point the charger goes into float mode or maintenance mode to just maintain the battery charge. This is how most on-board chargers are designed to function.

To answer your question, most everything I read these days indicates that you should always recharge your battery as soon as possible after each use and as quickly as possible, within limits of course. A charger that delivers up to 10 or 15 amps is more than adequate for the job. If you don't have a smart charger be sure to avoid over-charging your battery as this will have negative consequences.

[Whoaru99]

If time to recharge is not a factor then smaller is (generally) better from my understanding as it's easier on the battery to be recharged "low and slow" vs "hot and fast".

More important than actually how fast the battery charges is how fast you put it on the charger. One of the worst things for this type of battery is to be left in a partially-charged state. Put it on the charger as soon as possible after use.

[BobT]

You should to be careful. Many think they are doing a deep cycle battery a favor by charging with a trickle charger. Recent research has shown this may not be true and there can be other problems. Not all batteries are created equal and likewise not all batteries should be charged the same way. Starting batteries, deep cycle batteries, gel pack batteries, and flooded lead-acid batteries all require their own unique special recharging processes. Will they all get recharged using the same charger? Absolutely but if you're interested in doing more than just enough to get by and increasing the potential life of the battery, then consider the needs of the battery and follow the manufacturer's recommendations for recharging.

I started doing my research because I noticed that my portable charger had a "regular" vs.

"deep cycle" setting on the charger and I wondered what the difference was. The difference had to do with applied voltage levels and recharge sequence. I can tell you from personal experience that a deep cycle battery doesn't always work well with some trickle chargers because a deep cycle may not reach a high enough impedence to turn off the charger. This can cause the electrolyte to be evaporated (boiled) out of the battery prematurely.

[delcecchi]

Just as a point of reference, I have a 3 bank charger that provides 5 amps per bank but will use leftover on another bank, so if only one of the three batteries needs charge it gets all 15. I have it hooked up to two deep cycles and the starting battery.

The batteries are always charged up by morning if I plug it in in the evening. A typical deep cycle battery with a RC of 180 is about 75 amp hours. If it is 2/3 dead, that is 50 amp hours. So 5 amps for 10 hours pretty much does it. And since the starting battery doesn't need that much usually, they are really getting 7.5 amps.

So even a 5 amp 3 bank will do it unless you don't sleep much.

[Northlander]

Get yourself a 10amp. I sometimes fish until 9 or 10pm at night and Im back out in the boat by 6am if not sooner at times. With my 10amp I never have a issue with not having my batteries fully charged.

[JohnMickish]

One more thing to keep in mind when picking out your charger is what size of batteries you have. A couple of group 27 batteries will charge much faster than a couple of group 31 batteries due to the reduced capacity.

If you go to big on your charger you will never know it, but if you go to small you will for sure. If your not going to be doing any 8 hour turn around trips on dead batteries and have time to charge them then get a 5-7.5 amp per bank charger.

[311Hemi]

You should to be careful. Many think they are doing a deep cycle battery a favor by charging with a trickle charger. Recent research has shown this may not be true and there can be other problems.

[Wish-I-Were-Fishn]

There is a difference between a trickle charger and a maintainer circuit.

[BobT]

There is a difference between a trickle charger and a maintainer circuit.

I can agree with this. If I'm not mistaken a maintenance charger might put out a slightly higher voltage so it can tell when the battery is charged a little more easily or something like that.