phil@brahms.amd.com (Phil Ngai) (01/15/91)
I just saw a magazine called "Home Power", with an article about sulphated lead acid cells. They claim you can rejuvenate them by putting a few teaspoons of EDTA in. Does this seem reasonable, or just hippie-dippie mumble jumble? It would be good to reduce the amount of lead thrown away or leaked into the environment. (anyone see "Global Dumping Ground" on PBS?) -- militia: 1.a. A citizen army, as distinct from a body of professional soldiers. b. The armed citzenry, as distinct from the regular army.
amirza@silver.ucs.indiana.edu (anmar mirza) (01/15/91)
In article <1991Jan14.185450.24785@amd.com> phil@brahms.amd.com (Phil Ngai) writes: >I just saw a magazine called "Home Power", with an article about >sulphated lead acid cells. They claim you can rejuvenate them by >putting a few teaspoons of EDTA in. Does this seem reasonable, >or just hippie-dippie mumble jumble? > >It would be good to reduce the amount of lead thrown away or leaked >into the environment. (anyone see "Global Dumping Ground" on PBS?) Yeah, some friends of mine and I were very interested to read that. As soon as I can secure some I am gonna give it a try. I have a couple of highly sulfated batteries lying around. Another way to get rid of sulfation that I have heard is to remove the acid and fill with pure water. Then charge at a high rate until the battery accepts some current then charge at a reduced rate. Then drain the water and refill with new acid sg 1.285. I am going to try this one as well. Another thing this old battery book I have mentions is lowering the sg of your acid for standby batteries. This reduces their cca's somewhat, but also reduces their tendancy to sulfate. Down to about 1.2 for a fully charged battery. I'll post results when I get them. -- Anmar Mirza # If a product is good, # I speak only my # Space, humans next EMT-A # they will stop making # opinions on these # goal in the race N9ISY (tech) # it. Unless it is # subjects, IU has # for immortality. Networks Tech.# designed to kill. # it's own. # --- me
gordon@news.colorado.edu (GORDON ALLEN R) (01/15/91)
EDTA, which basically stands for ethylene diamine tetraacetic acid, is a very powerful chelator of divalent cations. It has been used in basic research to remove divalent cations from solution, such as Ca++, Mg++, etc. It has also been used clinically to remove Pb and perhaps other heavy metals, from the blood of poisoned individuals. There is no reason why it should not work in batteries to remove those metals which might poison the electrodes. However, the ability of EDTA to bind those metals depends on pH as well as whether they are divalent in solution. Over time, however, EDTA would tend to draw off metals from the electrodes (through mass action). It would also tend to draw off Pb ions as well. Needless to say, the resulting solution must be handled and disposed of as a toxic chemical. Allen Gordon -- Allen Gordon * If all your folly were changed to * gordon@tramp.colorado.edu * intelligence and divided amongst a * gordon_A@cubldr.colorado.edu * thousand toads, each would be more * * intelligent than Aristotle *
moroney@ramblr.enet.dec.com (01/15/91)
In article <1991Jan14.185450.24785@amd.com>, phil@brahms.amd.com (Phil Ngai) writes... >I just saw a magazine called "Home Power", with an article about >sulphated lead acid cells. They claim you can rejuvenate them by >putting a few teaspoons of EDTA in. Does this seem reasonable, >or just hippie-dippie mumble jumble? > An automotive club's newsletter I get mentioned the exact same thing, prolonging the life of a battery with EDTA. The EDTA apparently locks up lead ions as they're formed before they can form the lead sulfate that ruins batteries. The EDTA apparently isn't that stable in the acid environment of a battery, but the article claims that isn't really a problem since the lead sulfate forms tends to fall to the bottom of the battery rather than on the plates, and the EDTA can do its job again. I have some weak batteries to experiment with, if I can get the stuff, I'll try it. -Mike
rrw@naucse.cse.nau.edu (Robert Wier) (01/16/91)
I've tried battery additives and have NEVER found them to work successfully. Course, it may be that I don't try it until the bat is already beyond recovery. I'd be most interested is anyone has success with this. - Bob Wier -------------- insert favorite standard disclaimers here ---------- College of Engineering Northern Arizona University / Flagstaff, Arizona Internet: rrw@naucse.cse.nau.edu | BITNET: WIER@NAUVAX | WB5KXH or uucp: ...arizona!naucse!rrw