Most lead-acid battery manuf. recommend adding distilled or deionized water. I was talking today to a distributor of said batteries who seemed pretty much on the ball about every minutia regarding large batteries, and he said they just use regular city tap water. Told me about one guy who took super good care of his electric forklift, (such that he even *waxed* the damn thing), who told him his battery lasted *25 years* and he just used Greenville, SC tap water.
My theory is that the whole "distilled" or "deionized" bit may be a blanket statement such that users don't use *well* water, which may indeed have some problematic particulants, but most municipal water should be ok.
How much city tap water you can run through a battery depends on the dissolved minerals. Sodium, calcium, iron, etc all form strongly bound sulfates. Every sulfate ion lost to minerals is that much acid less to make charge.
Some cities have very pure water. We used to but not any more since most of our comes from wells and not Lake Casad.
Any thoughts on which would be better..distilled or deionized ? Is one more "pure" than the other ?
Theoretically distilled is more pure. De-ionized, means that the water is run through ion exchange resin columns which will remove all the cations and anions, or in other words any dissolved ionizable "salts".
Good question Don. I only know about distilled spirits, not water.
Is the Chlorine and Fluoride added to drinking water a concern? I use distilled water to avoid these in my batteries, maybe it is not necessary. Actually I have been known to use water from the dehumidifier or captured rain.
Forgive my being 'absolutist', but distilled or deionized is the ONLY way to go.
Battery manufacturers have improved on the grid framework which holds the sponge lead (negative) and lead dioxide (positive) active electrode matrix. They did this by incorporating trace metals into them, and batteries today ARE more tolerant of foreign ions than they were in the 50s and 60s.
That said, if you want longest bettery life, use pure water; no difference between distilled and deionized. Costs me 97 cents a gallon.
Biggest offenders regarding impurities are IRON, CHLORIDE, and ACETATE. Acetate is the worst, and can get into your battery via water contaminated with vinegar or antifreeze (ethylene glycol, oxidized at positive to acetate). The latter usually gets into the battery by using a hydrometer for testing antifreeze specific gravity, then using it to test or drop water into the battery.
Iron and chloride are second worst and equally bad. The iron never gets out and sets up local galvanic currents which auto-corrode the plates. Chloride is oxidized to hypochlorite and, well, do you think your battery would like a draught of Clorox???
Arsenic is also a problem (not sure of chemical reason), but, interestingly, the closely related element antimony actually is one of the things battery manufacturers use to make the grids more resistant to damage by impurities.
DW is cheap; use it, and it alone; ditto for your wife's steam iron.
Hey D.- My grandmother lives in Greenville, and for years the big treat was that she would bring down 5 gallons or so to Charleston on her visits! Must be something magic in that water... does taste good!
A few months agoI had aproblem with rain water running through the weatherhead going to my home.I noticed that the water was running down into the inside panel.Turned out the weatherhead was not at the right elevation.The guy from the power company said not to worry.According to him rain water is deionized and therefore won't carry an electrical charge.I told him that I had a gallon of deionized water in my shop and a 230 volt test lead and we could conduct a test.I told him I would put the test lead into the water and he could stick his hand in it and I would hit the breaker.Of course he wouldn't do it.It got me to thinking about this when I read Don's post.Until just lately I've always used well water in lead acid batteries.Now I use deionized but if what this guy told me were true then it looks like I would be slowly killing the batteries.
S, that's ironic as I would think what makes water taste good are certain trace minerals that would be bad for a battery !
Speaking of water taste, Consumer Reports did a comparison study of bottled water about ten years ago and found the purest and best tasting water to be New York City tap water !!
Ray, maybe it was just Mebane, NC, but I found "guy's from the power company" not the sharpest tacks on the board
Use distilled, or de-ionized. Both are similar. The distilled may actually contain more "stuff" than de-ionized, IF it "distills over" with the water. Luckily , not much does. As someone alluded to, "distilled spirits" are anything but pure......but they are distilled.
Any other "stuff" in a wet lead acid battery other than what was in there to start with, is generally bad.
The good news is that you don't add much water, and the water doesn't have much stuff in it. So the total amount of "battery poison" you add is low if you have to use less than the best sometime.
As far as "salt" and batteries, ask someone who was in diesel submarines what happens when salt water gets into the batteries....(yes I know there are lots of "salts" that are not "salt").
I wonder if one can trust those 97 cent bottles of distilled water from the grocery store to be "really" distilled ?
In doing some Goggle searches one place advertised deionized water for lab use at $29.95 a gallon !
Ask that guy if that nice pure deionized water will still be that way if your hand (which is coated in salts from your sweat glands) is in it. How many ppm of electrolyte does it take to conduct.....NOT MUCH!!!
I really couldn't tell you much more than you already know about the operation of batteries than anyone else. Since you posed the question from the practical standpoint, I'll just pass on two generations of experience.
When I was growing up, my father had four forklifts in the 18 to 20K range, three Mack trucks, tractors, a Willys Jeep, and my parents each had a vehicle. We were always buying batteries. He began phasing distilled water into his batteries, especially after replacement. The life of them improved dramatically. I have not tried de-ionized water, but my batteries that I upkeep using distilled water nearly always last past their labled life expectancy. Some of the batteries sit for most of the time, as the equipment they're in is only needed occasionally.
I'd definitely recommend it in your expensive forklift battery rather than tap water. We had an electric lift or two over the years (but I'm not sure I'd ever go back to them) and I used distilled water for replenishment.
If you don't trust grocery store DW, you could made your own by running tap water through one of those ion exchange resin purifiers they sell for steam irons.
Les knows about distilled spirits. Need to keep those out of battery as well; ethanol is oxidized to acetic acid at cathode. Acetic dissolves the grid framework (PbAc is soluble); the PbAc then reacts with H2SO4 to make PbSO4, which means now your grid is 'dust' at the bottom, AND in that reaction, acetic acid is regenerated to do it all over again. Even a drop of acetic in your battery, and it's toast in about a year.
Wanna know the purity of your battery water?
Simmer away a pint of it in a spandy clean glass pot. Look for residues as a film on the glass. No residues = pure water.
Run a gallon through this test a pint at a time and you can detect (but not quantify) total net total non-volatile contaminiants down to 1 part per million.
[This message has been edited by Forrest Addy (edited 05-26-2004).]
Re 97 cent bottles of distilled water, I never said I don't trust them...I'm asking you guys if *you* trust them !
My water comes from a well here in foothills of N. Calif., and if I put it in a battery I could count on replacing it soon.....It's loaded with Iron, Calciun and who knows what else.....DW only.....
My water is so mineralized I won'tuse it as engine coolant because of the corrosion it causes.....I mix DW with anti-freeze and add RMI-25 (a coolant conditioner).....Over the years I've noticed that engine cooling systems stay much cleaner than when I used city and well water.....
Don, I totally trust grocery store DW.