charging deep cyles

[jwmiller33]

what is the best way to charge a deep cycle, that you use for say a trolling motor? trickle charge? other ways?

where is a good place to buy this type of charger

[wplatehunter]

I have a charger that is for both deep cycle and cranking batteries if they are not deep cycle. I can switch from 10amp to 4amp. I always use it on 10amp, but I only use that charger in the winter for the fish house. The batteries I keep in the boat are all on on-board chargers. They come in different amps for charging. You can buy chargers at any sporting goods stores.

[upnorth]

I charge mine at 10 amp and have for years and never had a problem.

[Surface Tension]

An automatic deep cycle charger. Depending on the charge of the battery the charger will charge it at the appropriate rate. As the battery nears full charge the charger will taper down till it the battery is fully charged.

Charge the battery after every use.

Keep the fluid level up.

Heat is a battery killer,

keep them out of direct sun,

especially when charging.

[BobT]

Here's the answer from Exide

What is the best way to charge my deep cycle battery?

1. The electrical capacity of the battery charger determines how long it will take to charge your battery. In most applications, a 10-25 amp charger is recommended. First, determine the battery's state of charge using a hydrometer, voltmeter or state-of-charge indicator.

2. Check electrolyte level before charging. Add distilled or good quality drinking water if the electrolyte level is below top of the plates.

3. Follow the instructions provided with the charger. There are many chargers on the market, each with their own features.

4. Be sure the battery is completely recharged. Use a hydrometer to determine the percent of charge, following the manufacturer's instructions.

5. Recharge within 24 hours after each use. Discharged batteries can freeze.

6. Do not overcharge your battery. Overcharging causes grid corrosion and reduces battery life. A charger with a timer switch is best.

7. Do not use a fast boost charger. A slow charge is best for a deep cycle battery.

8. Unhook the charger when the battery is fully charged.

Note: special instructions for charging of gel products

Gel products are charged according to use or application. Use in backup applications where the battery is charged continuously (float) requires a different charging method than in discharge-charge cycling applications where the battery is not continuously charged.

[Whoaru99]

IMO, the best way is with the 3-stage chargers.

Nearly all on-board chargers are this way, and several brands make portable chargers that use the 3-stage method.

How many amps of charger you want/needs depends mainly on three things.

1. Size (amp-hours) of the battery.

2. How much the battery is drained.

3. How soon do you need the battery to be recharged?

Math works...

Typical deep cycle battery might be 105 amp-hours. Say you drain this battery to 50%. That means you have to return roughly 53 amp-hours to bring the battery back to full charge. Generally, you need to add another 10% for good measure.

So, that means about 60 amp-hours need to be returned back to the battery for full charge.

If you have a 5 amp charger, 60 amp-hours divided by 5 amps charging, means about 12 hours to fully recharge the battery.

If you need faster time to full charge, then you need more amps from the charger. 10 amp charger will cut the example time roughly in half to about 6 hours. A two amp charger would increase the time by 2.5x to roughly 30 hours.

Of course, if you have smaller or larger battery, or drain it more or less, the times change proportionally.

Both portable and on-board 3-stage chargers can be had at outdoor/sporting goods/marine supply houses. Or, if you shop online, there are places that offer considerable savings in some cases.

The key, regardless of what charger you end up with, is to use it as quickly as possible after using the battery. Never let the battery sit in a state of partial discharge, even a little bit, any longer than necessary. Yes, that means hook up the charger when you get home from fishing, not waiting to charge the batteries until the next time you want to go fishing.

Therein lies the beauty of onboard chargers, takes about 30 seconds to plug it in and you're done.

[BobT]

Whether onboard or not, how does it take any longer than 30 seconds in either case to hook up?

Onboard is nice because it is a convenience but if you only have one battery to maintain, it's a huge waste of money.

Where they really add benefit is when you have multiple batteries. The onboard charger will recharge all at once and all you have to do is plug it in.

[Whoaru99]

It would take longer than 30 seconds on my boat because my batteries are in covered, strapped down battery boxes, which are then inside closed/covered hatch compartments.

So, regardless of one battery would be much more work and much longer time than simply plugging in the extension cord.

A single-bank OB charger can be had for $50-$60. The convenience alone is well worth that over the course of several years, to me, anyway. Guess it might not be for others.

[BobT]

When you put it that way....