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

Roland,

Remarkable that I would use the same term for something that I
had never heard of below (what's in your bottom paragraph).
Different things, same term.

Thanks,
Chuck

----- Original Message -----
From: "Roland Wiench" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, August 06, 2007 4:41 PM
Subject: Re: [EVDL] Sugarcoating and
cellphotography(WAS:Floodies/Batt.murder mystery)


> Hello Chuck,
>
> Sometimes battery companies do not make any of the components
for the
> batteries. They may purchase the plastic cases from one
company, the tops
> from another, the lead grids which may be un-pasted from
another and the
> battery compound that is pasted and rolled in the grids.
>
> You can get them pre-pasted, which is a compound of lead
peroxide for the
> positive plates and spongy lead for the negative plates. To
make them into
> a paste, H2SO4 is mix in to make this paste.
>
> To prevent them from sulfating while shipping and assembling,
the plates are
> dip in a solution that was normally call SUGARCOATING, because
back in the
> 30's this is what was done, dip the plates into a solution of
water and
> sugar to protect until the electrolyte was added, so this term
may be use
> today.
>
> Roland
>
>
>
>
>
>
> ----- Original Message -----
> From: "Chuck Hursch" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Monday, August 06, 2007 3:23 PM
> Subject: 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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> > > >
> > >
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> >
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> >
>
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