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lead acid battery chemical analysis results

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dnix71:
I used to work for a commercial printer that used cast lead alloy type to imprint napkins, match covers and items like those that would not feed through a regular offset press. Management was cheap. We recycled and recast the alloy until it was neccesary to buy more.
Antimony was the one element that just had to be right. It hardened the cast so that we could get more impressions from a set of cast type. Too much made the type brittle and not fill the mold crevices correctly. We could get lead locally from ship builders, but keel lead can be pot metal if necessary.
People who reloaded bullets also need a certain hardness, too.
Too much antimony makes battery plates brittle and subject to breaking if the battery is mobile.

Mary B:

--- Quote from: dnix71 on January 04, 2024, 07:31:55 PM ---I used to work for a commercial printer that used cast lead alloy type to imprint napkins, match covers and items like those that would not feed through a regular offset press. Management was cheap. We recycled and recast the alloy until it was neccesary to buy more.
Antimony was the one element that just had to be right. It hardened the cast so that we could get more impressions from a set of cast type. Too much made the type brittle and not fill the mold crevices correctly. We could get lead locally from ship builders, but keel lead can be pot metal if necessary.
People who reloaded bullets also need a certain hardness, too.
Too much antimony makes battery plates brittle and subject to breaking if the battery is mobile.

--- End quote ---

Tin was also used, helps mold fill out/adds toughness. Foundry type(individual type letters that got set in rows) is 60.5% lead, 25% antimony, 12% tin and 2.5% copper.(copper is up for debate, I have never measured it in it). Tin makes for sharp clean corners and a tougher alloy.

joestue:
The problem is the antimony has a 50mv difference in voltage, causing self discharge and water loss.

We did get a tin standard so will run more tests.

I have read of attempts to make a lead antimony positive plate and a lead negative plate, but apparently it plates over to the negative plate and you get the water loss problem again.

joestue:
Ran the same battery samples again (a chunk of positive grid plate is dissolved in nitric acid) and the tin results came back with significant variation.

The genesis battery was .14% tin. it allegedly lasted 7 years in an APC ups

the CSB was .3% and the BB battery was .08% -these batteries lasted a couple years.

this is all noise until more samples are run from dozens of batteries and correlated with the different environments.

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