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Re: [EVDL] Sugarcoating and cell photography (WAS:Floodies/Batt.murder mystery)

Hi Roland,

I think all the batteries were made in the same batch, as the
lady over at American Battery in Hayward told me when I ordered
them that they would send in the order to have them made up.
They came to Hayward, I believe from SoCal, within a few days.
They sat on the shelves for about three weeks till they were
delivered to the place where the battery pack swap was going to
be done. All cells were low on electrolyte, something that kinda
ran through my mind when I opened them up for the first time. I
don't think either of my previous two packs came with electrolyte
levels this low; the previous two were a bit below the bottom of
the filler neck, although it's been awhile now. Months later,
when I asked Jim Ramos at American Battery (he is our US Battery
connection here in the Bay Area for us EV'ers, and has largely
been supportive of our efforts and getting us good deals), he
said something to the effect that the levels were low to allow
for plate expansion during cycling of the battery. He also told
me that this white powder, sugarcoating, or whatever one's going
to call it, is normal. Well??? I'd never seen this stuff
before till I deep-cycled this pack some six months in after
working on adding all that water. Never on my previous packs,
and while the second one never went more than about 25 miles on a
charge (never pushed it further than that), the first saw over 60
miles several times. Never any sugarcoating. Also, I've never
noticed an appreciable effect in what Jim Ramos mentions as the
electrolyte level rising over time - yeah, the cases bulge out as
the batteries are cycled and aged, but I've never had overflowing
electrolyte out of the cell holes.

I think basically what I've learned here is that when the
batteries were made up, not enough electrolyte was added at the
manufacturing facility. I did a big goof, and I wish that other
people that I was talking to about this had warned me about it,
in adding a lot of water over several months to get that
"electrolyte" level up (that always seems to be the goal, since
these batteries are supposedly "acid starved"). What I should've
done is waited awhile in leaving the electrolyte levels alone,
say a couple of months, to get the batteries cycled in and the
specific gravities as even as possible around 1265, then started
working on adding 1265 electrolyte to the cells, a bit at a time,
see how the batteries react with sg and appearance of the plates
(and perhaps a load test or two), till the electrolyte level is
up at or near the bottom of the filler neck. I always do my
adding of electrolyte or water when the batteries are fully
charged (or as charged as I can get them, seems to be the case
really - Lee's balloon paradigm). Now with full electrolyte, I
would have more A-hrs available, and it would also mean I could
be harder on the plates if I chose to, by cycling them deeper,
according to what I've read from Roger.

So how many other gotchas are there in Battery Land? I've been
at this for thirteen years, and I still bounce off of walls.
This third pack has been a good learning experience, and maybe
I'm finally beginning to understand. Unfortunately, it's an
expensive learning curve if you zorch a pack or two. I haven't
killed one yet, but it sure has upped my "dandruff factor" as I
try to figure these things out.

Thanks,
Chuck

----- Original Message -----
From: "Roland Wiench" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Saturday, August 04, 2007 6:48 AM
Subject: Re: [EVDL] Sugarcoating and cell photography
(WAS:Floodies/Batt.murder mystery)


> Hello Chuck,
>
> I have work on 300 ah cells in clear glass cells, and seen the
effect of
> high charge, high discharge, different electrolyte SG and
levels had a
> effect on them.
>
> Also initial filling a battery cell with the a electrolyte of
let say it is
> at 1.275 SG and trying to charge them to bring up the water
level, is only
> going to overcharge the positive plates PB02 which will blow
out more
> material, the sulfate on the negative plats as larger particles
that may
> settle to bottom of the cell or even float in the electrolyte.
>
> If the electrolyte was too low initially, meaning that the
manufacture did
> not finish filling the cell to the correct level, then that was
the time to
> add more electrolyte of the same SG at the time.
>
> After the battery was charge and discharge many times, and if
the
> electrolyte level is still too low after charging, then take a
reading of
> that cell electrolyte SG and only put in the same SG
electrolyte. If it
> reads 1.250 SG, only raise it to the correct level after
charging with a
> 1.250 SG.
>
> Sometimes a battery can get out of balance, by adding water to
a discharge
> battery and then charge it. This will over charge the battery
by trying to
> bring up the SG of the electrolyte which boils off the water.
>
> It is normal for the electrolyte level to drop during
discharging and raise
> during charging. If a cell is so low in electrolyte which is
below the
> plates, only add enough distill water to get the level just
above the plates
> and than charge the batteries to about 1.250 SG or about 80 to
90% charge
> and then add distill water at that time.
>
> Finish charging to 100% will mix the water better with the
electrolyte by a
> low bubbling simmer.
>
> If a PB-acid battery has been setting for awhile without use,
do not take a
> SG reading at this time, why, because the water is lighter than
the acid,
> PBSO4, which settles to the bottom of the cell, which may even
read as high
> as 1.320 SG while the top of the electrolyte may read 1.250 SG.
>
> So all these things can throw you off, which is cause by the
initially fill
> battery, charging at the wrong time and thinking that the cell
is low in SG
> where it may be higher.
>
> The white stuff that is floating around looks like power chalk,
is the SO4
> or sulfate that is coating the negative plates while
discharging.. If you
> could look at the negative plate, as I have done, this will
look like hard
> chalk if expose to the air and looks like a silver gray paste
while its in
> the electrolyte.
>
> If you see red or a reddish brown color particles floating
around in the
> electrolyte, this is normally cause by too high of a discharge
that is not
> design for this battery. The positive plate which is PBO2,
lead oxide, may
> release the O2 material under a heavy discharge. I had seen
this on the 300
> AH cells that was discharge at 600 amps for a length of time.
>
> Look at the manufacture dates that are stamp in the battery.
They always
> hide this with a code. You have to ask the dealer what the
date is or you
> can look it up a battery web site to find out.
>
> Back in 1985, I bought 30 new batteries, which I found out that
10 of the
> batteries where setting at the dealers which were not on
maintainers and was
> over 9 months old where mix in with 20 new ones that where
order in.
>
> Some of the older batteries blew there tops off, the minute I
press on the
> accelerator and took out the new batteries. I made them
replace them right
> now! If a battery post does not stand up, studs pulls out,
post are
> discolor by post seal leakage, replace them right now!
>
> Roland
>
>
>
>
>
> ----- Original Message -----
> From: "Chuck Hursch" <[email protected]>
> To: "EVDL post" <[email protected]>
> Sent: Saturday, August 04, 2007 1:56 AM
> Subject: [EVDL] Sugarcoating and cell photography (WAS:
Floodies/Batt.murder
> mystery)
>
>
> > Hi All,
> >
> > I just wanted to get back to Roger, Roland and others on
this.
> > Roger had wondered in private discussion last November what
this
> > sugarcoating was, what appears to be white crystals on top of
my
> > US125's plates. Roland had suggested something to the effect
> > that my battery chemistry had gotten out of whack. To
reiterate,
> > I had received my batteries from the local distributor in the
> > May/June 2005 timeframe. I shortly noticed that the
electrolyte
> > levels were the lowest I had ever seen in new batteries, and
> > certainly far lower than I ever had in my previous two packs
(my
> > first pack was US2300s, second was Trojan T125s). Specific
> > gravity (sg) readings were quite low too, and never came up
very
> > well. Battery weight seemed ok at about 65 lbs each. Over
the
> > next few months, my goal was to add water to reach the
meniscus
> > level on the filler neck. I got there, yep. Then somewhere
in
> > there I went on my first long drive, some 40 miles with total
> > elevation gain of something like 1500-2000 feet. Shortly
> > thereafter, I noticed a whitish crystalline coating on the
tops
> > of the plates, something I had never seen before on any of my
> > previous packs. My sg readings took a dive of maybe 20
points.
> > About a year later, I load tested my pack to 5.25V @ 75A,
which
> > went about 105 minutes before the first battery hit 5.25V
(not
> > bad). Very cloudy electrolyte at the end of that load test.
A
> > few days or a week or two later, had a look-see in a cell,
and
> > was rather shocked to see even more whitish coating (I call
it
> > sugarcoating).
> >
> > To digress, it's rather difficult to take a picture of a cell
in
> > a battery that's a member of a pack, like in the car. It's
dark
> > and gloomy down in there, and any light shined in tends to
> > reflect on the surface of the electrolyte. So a flash is
more or
> > less out. A polarizing filter might work, but I don't know
how
> > well they work with your typical digital camera, and they are
a
> > bit pricey. A fellow EV'er suggested using a prism in line
> > between the camera lens and the cell, which prism would have
a
> > light shown on it from the side - the light would bounce down
> > into the cell and be reflected back up through the prism to
the
> > camera, polarization issues taken care of; I haven't had a
chance
> > to try this out, but he said they used something like this at
> > work in the past. I had the idea of maybe running some fiber
> > optic light tubes down into the filler neck, spread them out
> > through the vertical slots in the filler neck - that would
> > probably keep the reflections off to the side, and might work
as
> > long as I could control the fibers going into the cell and
keep
> > them out of the way of the camera. But it all came down to a
> > couple of months ago me going at it with an LED flashlight,
> > offset slightly along the side of the camera body, and I was
able
> > to get the images referred to below with a bit of squirming,
> > teeth gnashing, and mouse pushing with some image processing
on
> > the computer. Drum roll please!...
> >
> > At http://www.geocities.com/chursch/batteries/cell_pics:
> >
> > IMG_1123: This is a shot of one of my spares (I buy 20
> > batteries, 16 go into the car, 4 are kept for spares and to
serve
> > as an eventual UPS for the computer). Said spares was low on
> > electrolyte at the start, as were the others. I added a
little
> > water. The spares have been equalize-charged once a month at
> > "constant" current (I use a variac here) till the voltage no
> > longer rises. sg is in the vicinity of 1260-1270. Nothing
that
> > I call sugarcoating appears here.
> >
> > IMG_1144: Here's a shot of some sugarcoating (that white
stuff)
> > in one of the car's cells. The sg of the particular cell
seems
> > to bear no relationship to how much sugarcoating there is.
Some
> > cells have more than others. There seems to be less
sugarcoating
> > as time goes by, but I suspect most of it may be going to the
> > bottom of the battery, potentially causing sludge problems
there,
> > and I doubt the white stuff is ever going to fully disappear.
> >
> > I have a vote from one knowledgeable Bay Area EV'er that the
> > sugarcoating is lead oxide; however, I did not have an image
to
> > show him at the time. I'd be curious as to what Roland,
Roger,
> > et.al. have to say.
> >
> > Also, I'd be curious as to whether anyone has done cell
> > photography of cells in a pack. Tips? We had one photograph
I
> > recall from many years ago that someone had taken of an 8V
> > battery cell. It looked like a bunch of worms down in that
cell,
> > with the plates expanding over the tops of the separators.
> > However, I think that battery was out in the open, so light
could
> > shine through the case.
> >
> > Remarkably, I have some hope for this pack. I think it is
fairly
> > likely to get me to the 10K or 12K mile points that I
consider
> > the minimum to financially justify a pack (and it only gets
> > harder to justify as the battery prices keep climbing towards
the
> > stratosphere). I'm at 7K and change now. The pack is
feeling
> > stronger, and the sg readings are all rising as all that
water I
> > put in is getting gassed off. When the electrolyte levels
get
> > back down about where they were at the start of this whole
> > affair, the sg readings bob up rather quickly, like little
ducky
> > toys in a tub. My pack average is now at 1262. When a cell
> > reaches about 1270 or better, and is getting the level kinda
> > close to the tops of the separators, I'll add some water, not
> > much, and it's a guesstimate, but so far that has served me
> > fairly well. Maybe a quarter or a third of the cells
required
> > some water in last month's battery maintenance.
> >
> > I'm also trying what some people suggested several months
ago,
> > and that is not charging every night - wait till the pack
gets to
> > 1/3 to 1/2 of the way down, whatever that is. When I'm
working,
> > I drive far enough so that I do need to charge it every
night,
> > although I'm close to being able to do it every other night.
The
> > last couple of weeks, I have been on vacation, and I have not
> > charged it every day I use it. This seems to work well,
seems to
> > "stretch" the pack some. I begin to wonder if charging the
pack
> > every night after every little short trip causes problems for
the
> > batteries, like maybe some layering ossification of the plate
> > structure. Pores close up? ??
> >
> > My plan is to get all the cells in the vicinity of 1260-1270.
I
> > think this is going to take several more months, because one
is
> > still back at 1220-5, and several are residing in the 1240s.
> > Once I get everyone at 1260-1270 or as close as I can get it,
> > I'll likely try a load test, say to about 60 minutes @ 75A,
to
> > see if I have any baddies. Wait a month or two to see how
things
> > go post load test. Then I'm pondering adding in 1265
electrolyte
> > in stages over a few months up towards the meniscus level. I
> > have heard these batteries termed acid limited, so supposedly
> > having more electrolyte on hand will give the battery greater
> > capacity.
> >
> > But by then, my batteries will be a good three to four years
old,
> > so maybe it isn't worth it. We'll see.
> >
> > Suggestions?
> >
> > Thanks,
> > Chuck
> >
> > _______________________________________________
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> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
>
> _______________________________________________
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