MUST READ-= Battery Information

[kevfish]

I have 2 deep cycle batteries for my fish house. On my last fishing trip I only got one day out of the batteries, just running a fan and light. They were fully charged before the trip.

When i got home I checked the water level in them. They were both low. I added water to them and then charged them back up. I then tested them by putting them in the fish house and runninning the same fan and light. I got 3 days out of them this time. I then charged them up and ran the same test again. This time I got 4 days out of them.

What this tells me is to check the water level in the batteries and maybe a couple times a year run them down and recharge them. I think I have " Built my batteries back up"

Hope this helps

[Giant_Jackpot]

Good point on the water level. As you charge your batteries some gassing occurs and that leads to loss of water. But don’t run your batteries down on purpose just to exercise them. Lead acid batteries like to be kept charged. NiCAD batteries on the other hand give their best performance when you do fully discharge them.

[kevfish]

How would you explain the fact that I got more out of the battery after drainingg it almost completely and then recharging it? Maybe because it was the 2nd charge after adding water?????

[Giant_Jackpot]

Most definitely the adding of water and charging. I gained my battery knowledge while working at a place that designed battery chargers for all types of batteries. If you dig into a battery manufacturers web site you will find info that says not to completely discharge lead acid batteries. Obviously we can't avoid it sometimes but the nature of the beast is they don't like it.

[BLACKJACK]

I had a deep cycle that just wasn't taking a charge anymore, I thought it was shot, checked the water and added a little but it wasn't really down that far. Still didn't charge very long, then I read the original post here, and went thru a couple of cycles of running it down and charging it back up, now that 12 volt light will run all day. Morale of the story, adding water is not the cure all, they need to be run down and recharged also.

Now after reading the later posts, they say not to run it down compeletely, I'll have to admit I just hung the 12 volt trouble light on and left it for a day or two. Oh well.

[DuluthGuy]

OK

The Lead Acid battery is made up of plates, lead, and lead oxide (various other elements are used to change density, hardness, porosity, etc.) with a 35% sulfuric acid and 65% water solution. This solution is called electrolyte which causes a chemical reaction that produce electrons. When you test a battery with a hydrometer you are measuring the amount of sulfuric acid in the electrolyte. If your reading is low, that means the chemistry that makes electrons is lacking. So where did the sulfur go? It is resting to the battery plates and when you recharge the battery the sulfur returns to the electrolyte. Ergo, no water NO current~

B2

[delcecchi]

The sulfur can also form Sulfate, must be lead sulphate, that isn't soluble or something. Anyway, it is inactive. That is something that wrecks batteries. Some chargers claim to reverse the process.