----- Original Message -----
From: "Gary Patterson" <
[hidden email]>
To: <
[hidden email]>
Sent: Tuesday, November 10, 2009 5:49 PM
Subject: [EVDL] battery equalization..... brown sediment
>
> I equalized my ev pack for the first time today. The cells bubbled gently
> and nothing got too warm. Then the electrolyte got cloudy with a light
> brown sediment. Have I ruined my batteries??
>
>
>
> Gary
>
Hello Gary,
This does not happen after the battery ages over a period of time. If these
are new batteries, check the manufacture date. If they are over three
months old after you received them, then these batteries have not been
recycle by the dealer.
My battery dealer never have batteries over 3 months and if they are charge
in the 3rd month, there must be dealer date stamp that he has done this
which is require by the manufacturer. Sometimes there is a dealer label on
the side of the battery that notes this.
This brown material is the active positive plate material that flakes off
which is lead oxide. It builds up in the bottom of the cell. When you do a
equalize charge, some cells that are fully charge to 100% SOC, are
overcharge, while the other cells are charging.
The cells that are at 100% SOC, the electrolyte is receiving most of the
charging energy and not the grids. This action or bubble factor is stirring
up this material.
This happens faster when the batteries are cold. When charging a cold
battery the battery plates expand and while discharging they shrink back
which causes more of this lead oxide to flake off.
This action normally happens after the batteries that have soft active
material or pure lead and have about 2000 or more cycles and/or four or more
years on them.
Manufacturers of some battery harden the active grid compound with antimony,
cadmium or cobalt to increase there life. My last set of batteries had a
lead antimony alloy. They went 8 years and 8 months with out any lead oxide
material in the electrolyte.
My first set of batteries back in 1975 had this lead oxide floating in the
electrolyte, because the batteries where in aluminum boxes that was expose
to very low ambient air. This show up only after 8 years of usage.
Roland
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