# [EVDL] Neglected battery progress



## EVDL List (Jul 27, 2007)

I've been working on these 12 severely discharged Optima YellowTops for 
about two weeks now. They all have Rudman Mk2B regulators, and my 
PFC-20 is set to less than 1A and way more voltage than they'll need. 

Whenever the charge voltage just won't go any higher -- like I've been 
charging for a day without even 0.5V change -- I let them rest for a day 
or two and start again. 

I've got 7 batteries blinking and 167.0V on charge now. 

However, I'm stuck there, and I'm starting to see some wild current 
fluctuations. I think the regulators are eating the current, and as 
more of them blink on together, I can go from 0.4A to 1.1A.

My plan is to let everything cool down for a day or two, measure them, 
then shock them with as much current as I can send through them for five 
minutes or so, while I watch closely. I'm hoping that'll break up 
whatever sulphur crystals are causing me trouble. When the *first* 
regulator starts blinking I'll turn the current down to 1A or so.

If this doesn't work, I'm planning on taking the stinkers out and 
charging them separately. The charger has a DIP switch for "stop on 
regulation", so I'm considering charging the batteries individually at 
high voltage and high current, stopping as soon as the light blinks, 
thus preventing gassing.

Any comments?

Thanks,
Jude

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## EVDL List (Jul 27, 2007)

> Jude Anthony wrote:
> > I've been working on these 12 severely discharged Optima YellowTops for
> > about two weeks now. They all have Rudman Mk2B regulators, and my
> > PFC-20 is set to less than 1A and way more voltage than they'll need.
> ...


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## EVDL List (Jul 27, 2007)

> Lee Hart wrote:
> 
> > If any are light, drill a 7/16" hole above each cell, and add
> > enough distilled water to bring it back to the same weight as the
> ...


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## EVDL List (Jul 27, 2007)

> > Lee Hart wrote:
> >
> >> If any are light, drill a 7/16" hole above each cell, and add
> >> enough distilled water to bring it back to the same weight as the
> ...


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## EVDL List (Jul 27, 2007)

If one does the Water Loss process Lee suggests, I think it would be intere=
sting to first
determine the weight differential. Then, measure out that weight in dist=
illed water.
Then start filling (equally? unless some cells are lower than others, I =
suppose) the cells
and see if they take on that amount of water. At that point the weights =
should match.
I'd be surprised if it required more water than that. If so, maybe you b=
oiled the lead off! 
Scott
=3D=3D=3D


> Lee Hart wrote:
> >1. Water loss
> 
> Weigh the batteries. If any (especially the stinkers) are light,
> ...


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## EVDL List (Jul 27, 2007)

> Peter VanDerWal wrote:
> > I'm not sure what the point is of including the #6 screw if you are trying
> > to plug a 7/16" hole... ;^>
> > LOL ... {plop} Damn!
> ...


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## EVDL List (Jul 27, 2007)

> S Collins wrote:
> > If one does the Water Loss process Lee suggests, I think it would be
> > interesting to first determine the weight differential. Then,
> > measure out that weight in distilled water. Then start filling
> ...


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## EVDL List (Jul 27, 2007)

> Lee Hart wrote:
> > Charging for days at low current will keep the cases pressurized. That's
> > OK if your problem is equalization, and the seals don't leak. But it is
> > a bad idea in general.
> ...


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## EVDL List (Jul 27, 2007)

Well, this stinks.

I checked my batteries this morning, after letting them sit for two 
days. Here are the results, including the previous measurement:

1: 9.40 -> 9.82, sulphated neg post
2: 11.52 -> 12.44
3: 11.60 -> 12.33
4: 12.70 -> 12.70 (first to full)
5: 11.56 -> 12.28
6: 11.57 -> 12.33
7: 11.59 -> 12.43
8: 11.56 -> 12.53
9: 11.89 -> 12.62
10: 11.77 -> 12.55
11: 11.56 -> 12.44
12: 9.71 -> 10.50

So, 1 and 12 are still the stinkers, but everybody else is getting close 
to a good charge. I'm surprised by the sulphated negative post on #1; I 
checked the batteries at least twice every day, and I never smelled any 
sulphur or heard any venting. Unfortunately, I was taking voltages at 
the regulators last time, so I can't tell if it was already sulphated, 
or if that's something that happened during charging.

Luckily, I'm using a Curtis 1231C and Todd PC30, so all my components 
are rated down to 120V. I could just take these two out and start 
driving, which is quite tempting. My commute never gets above 45mph, so 
I don't really need 144V; I wanted 12 batteries for the increased 
range. We've also had many discussions on how to add fresh batteries to 
old packs, which I'll be searching for soon. 

Does anyone think it's worthwhile to try and save #12? It seems to me 
it couldn't have a reversed cell, or the voltage would be lower, but 
this is my first time dealing with such things. I've only got one 
charger, and it'll be used charging the car, so I won't have any time to 
charge it individually after I get driving; I'll need to make a decision 
soon.

I'll be taking the batteries out to weigh them soon.

Thanks,
Jude

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## EVDL List (Jul 27, 2007)

> We've also had many discussions on how to add fresh batteries to
> old packs, which I'll be searching for soon.

Don't do it, you'll be sorry.

> Does anyone think it's worthwhile to try and save #12? It seems to me
> it couldn't have a reversed cell, or the voltage would be lower, but
> this is my first time dealing with such things.

It's possible it has a shorted cell. The crystals could have grown enough
to puncture the separator.

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