Recondition old batteries

[jeff antonucci]

Anybody here have experience reconditioning old batteries? I have seen both de-sulfators and chemical treatments and I am wondering if anybody has had any luck with this?

My batteries charge up fine and hold 6.7 - 6.8 volts but run down very fast.

[jamescustomdesign]

I have not tried any of the fluids, but I do have a desulfator. It certainly hasn't worked any miracles, but I am hoping that it will keep my good batteries in better shape... I just try to keep my batteries watered and charged and hope they last. That is about all I know.

[mfrerking]

In my opinion, the best approach to use when dealing with older batteries is to identify the weakest point in the pack.

I have found batteries, with the voltages you reported, that have cells that are not fully charged. You may have to individually charge some batteries to bring all the cells up to full charge.

If the cell is found to be chronically lower, it may be better to swap it out with another battery.

If you do not find this to be a problem, then it might be time to retire the pack.

[Jerry71]

JEFF as with most maintenance programs they tell you to add WATER, but don't tell you that if you only add WATER you are weaking the mix EVERYTIME, I use pre-mixed acid when I need to top off a cell. I have also dumped the acid out and replaced it with new acid and it has brought some old batteries back to life for a couple years..

Jerry

[robert maxwell]

Hi,

My understanding of the battery watering problem---and I am no expert!---is that once the sulfuric acid is added when the battery is first made, is never lost. The gas that is formed when the battery is being charged is hydrogen from water, and the lead sulfate converts to sulfuric acid and lead oxide when electrons are applied to the cell. That is why a charged battery will have a higher specific gravity.

I've tried to take care of my batteries by using only distilled water because calcium and sodium in tap water can interfere with the chemical reactions. One mistake I used to make was by adding too much water when the batteryies were discharged and then would see some spillage of electrolyte when I was on a hill, or making sudden stops. One of the contributors to this website noted that before charging, to make sure the top of the plates are covered, but to wait till the charging is completed, and then topping off with H20. A good bit of info.

From the above, I'm less than enthusiastic about battery rejuvenators. I periodically (every 3-4 months) check electrolyt level, or more frequently if heavy constant use and frequent charging. I recently sprang for a digital VM which is much more accurate than my old heathkit VTVM, and am keeping a record of voltages when charged and also discharged voltages.One of the batteries I bought last year had apparently been in stock for several months (sulfated?) and initially the voltages were consistently lower (about .3 V) than the others. After about 6 cycles of charging/discharging it is now right even with the other batteries.

Anyhow, that's my 2 cents.

(The snow we've had here in SE PA has been a real test of my E20 and dozer blad!)

RM

[jeff antonucci]

Ok - thanks guys. I have been thinking about load testing the batteries individually to see how they respond. They are old and I don't know their history so an electrolyte check is in order. I hear auto parts stores sell battery acid. I'll check everything I can before I give up on them.

Robert - I'm in West Chester and were getting more snow now as I write this.

[robert maxwell]

Jeff,

Glad you survived the storm in West Chester. We made out fairly well here in Abington, except major tree limbs broke off a large pine tree, and before I could plow, I had to break out my chain saw. I ended up with concrete blocks draped over my snowblade, clearing brush, limbs and snow,but finally got the driveway cleared to be passable. We lost power for 24 hrs, also, but I recharged the batteries with a backup generator. I was able to plow for about an hour on 1 charge, and then put on the charger for about 4 hrs---long enough to get another hour of plowing.

Rob

[ddg]

There is plenty of info on the web on how batteries work or how they wear out... I've seen very little in the way of reconditioning aids that work effectively. HOWEVER, a previous poster suggested identifying the weak battery in the pack, and that's a good idea. If one battery goes dead before the others, the current being forced thru it will charge it up backwards... not good.

Here's a simple idea to make a pack monitor. I haven't done it myself, but it oughta work. Here's the basic idea:
Suppose one battery is going dead early; the voltage drop across it will diminish to zero. If you have a small 6v bulb in parallel with the battery, it should go out as the voltage decreases. (Perhaps you could put a diode in series with the bulb to make sure it doesn't light up when the battery charges up in reverse, but at basic a bulb is all that thould be needed. )

Now a single bulb wouldn't tell you much, but now imagine if you had 6 *identical* bulbs, one hooked across each of the batteries. You could see at a glance which battery was weak or had high internal resistance as soon as you began to draw heavy current!
You might even mount the six bulbs in an old distributor cap or a small aluminum box on the dash. Just to flesh this out, you'll want to provide some means of disconnecting the set of bulbs to keep from draining down the pack (a multipin connector or set of switches) and maybe a small fuse in series with each bulb (mounted at the battery terminal) to ward off sparky surprises if you pinch a wire.
Let me know if you try it. My Electraks (I have 3) are all sans battery packs at present.
Dave

[jeff antonucci]

I like that idea - I might have to try it. Wish I had a damn heated garage so I could work on this thing in Winter...

[ddg]

Just fill up a gallon milk jog with hot water, and wrap your hands around it whenever they get cold. Works for me!