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Discussion Starter #1
So I am finally putting in the 6V Deka GC15 in my car, and cabling it all
up, and being a little careless, as I "know" exactly what I am doing. My
wife comes to ask me a question, and then "oh no, your car is on fire." from
my wife. I run to the car, and see that one cable shorted on the negative,
hit the positive, and melted the terminals on both the positive and negative
side. The terminal is Offset post w/ vertical stainless steel 5/16" stud
and hex nut. Here is a picture of what it looks like:
http://www.eastpenn-deka.com/default.aspx?pageid=550

So my question is two fold. Can I fix the terminals? Or do I just need to
replace the battery? I remember some conversation in times past about
terminals not be good enough for ev use. Are these good enough? Or did I
waste my money on these batteries.

Thanks,
Brian
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Discussion Starter #2
Hello Brian,

Find a battery shop that can remold the post. I do this all the time if a
post after many years is reduce in diameter by a battery clamp or if you are
using a wire terminal lug link it will start to mushroom the battery post
and the stud may pull out if it's the low profile post.

To remold a battery post, you take a steel taper mold and place it over the
old battery terminal. I like to use a little larger type in the 300 amp
range which has a lead base at the bottom that sticks out about 1/4 inch
more in diameter. I also keep the top stud in this post.

It is best to discharge the battery to below 75% SOC and let it set with its
cap lose for about 24 hours before this work is done on it.

Clean up the old post and make sure there is a level area for the post mold
to set on. This work is normally done on a steel welding table, where you
can place a large magnetic base that can hold any type of tool which is use
to press the post mold down so it does not float and provided a tight seal.

Damp paper towels are roll up and replace the battery caps on the battery.
Layers of damp paper towels than cover the entire top of the battery
allowing the post to come through and packing the wet towels under the
offset lead base. Then the paper towels are than cover with a flame proof
material, that you can get from a hard ward store in the plumbing section,
which is use as protection when copper pipes are solder together.

You can get pure battery lead from lead battery clamps from a auto parts
store and hammer it out into a stick. I use a regular gas/oxy touch, but
sometimes those new mini touches will work that you can get from a hard ward
store which is refillable with a standard touch gas bottle.

You need a long pencil flame so as to melt the base and than you continue to
melt and a little bit of lead for about 1/4 deep at the bottom of the post
mold. If you need to install the stainless stud back in, use a bolt coupler
and threaded rod to place it into the molted lead and let set. Remove the
coupler and melt the top surface and continue to place in lead until it
forms a curve bottom on top.

It is best to use a brass plate heavy duty battery clamp that comes up to
the top of the post and torque it at 75 in.lbs. I then place a stainless
washer, lock washer and nut on the top, which also put down pressure on the
battery clamp and prevent it from shrinking as much.


Another tempory method I have use is to screw in a battery post into what is
remaining of the old post. You can get these screw on post from a auto
parts store. They come with a stud or with a tap hole to screw over a
battery stud.

If you use this method, you must provide a flat surface for the base of this
post to set on. If you still have the stud embedded, then clean both
surfaces with one of those stainless tooth looking brushes and screw the
post on with about 75 in. lbs.

If the stud is loose of missing, I was able to smooth the top of the
remaining post and drill a 1/4 hole about all the way through. I place
round spacer stop over the drill, so I do not drill through the offset link.
Then using a 5/16 course thread tapped in the plug type. They come in a set
of three which you start out with a taper, than go to a plug, and then
finish up with a bottom tap.

You then screw in the post that has stud built into it. Sometimes these
come in 3/8 inch size, so you will need to drill a 5/16 inch hole and use a
3/8 inch tap set.

I carry a on board tool kit to make this repair, or have additional links
long enough to jumper out a bad battery.

Roland






----- Original Message -----
From: "Brian Staffanson" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, September 24, 2007 12:38 PM
Subject: [EVDL] Oops and what to do now -- almost the EV grin, but not
quite!


> So I am finally putting in the 6V Deka GC15 in my car, and cabling it all
> up, and being a little careless, as I "know" exactly what I am doing. My
> wife comes to ask me a question, and then "oh no, your car is on fire."
> from
> my wife. I run to the car, and see that one cable shorted on the
> negative,
> hit the positive, and melted the terminals on both the positive and
> negative
> side. The terminal is Offset post w/ vertical stainless steel 5/16" stud
> and hex nut. Here is a picture of what it looks like:
> http://www.eastpenn-deka.com/default.aspx?pageid=550
>
> So my question is two fold. Can I fix the terminals? Or do I just need
> to
> replace the battery? I remember some conversation in times past about
> terminals not be good enough for ev use. Are these good enough? Or did I
> waste my money on these batteries.
>
> Thanks,
> Brian
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
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Registered
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Discussion Starter #3
Brian Staffanson wrote:

> I run to the car, and see that one cable shorted on
> the negative, hit the positive, and melted the
> terminals on both the positive and negative side.

How badly melted are the posts? Are they melted just at the spot where
the cable happened to touch? Can you post a link to a picture of the
damaged posts?

What type of terminal are you using on your cables; clamps to grab the
tapered posts, or lugs to bolt on the top using the studs?

If you are using battery clamps and there is just a spot on the side or
top of the post that is melted, then you can probably just clean up the
post with a file and bolt the clamp on securely. If you are using the
threaded stud and the damaged area is where the lug needs to press
against, then you might be able to clean the contact area up with a file
sufficiently. If you are using the threaded stud, you need to ensure
that the damage to the post is not extensive enough that the stud is
likely to pull free of it. If you were using lugs held by the studs,
you might switch to battery clamps on the damaged posts. You can get
good quality adapter-type clamps intended for marine use that clamp to
the automotive posts and provide a stud to which you can bolt a lug-type
cable (but replace the wingnut with a nut and lockwasher ;^).

You probably don't want to try casting on a post yourself, so if the
damage is too extensive to work around you might want to check with your
local battery supplier to see if he can repair it or refer you to a shop
that can. As a last resort, you could drill into the center of the post
to which your battery terminal is welded and insert a threaded stud to
allow attaching a lug-terminated cable. I don't know if tapping the
hole and threading in a stud would be as likely to endure as using a
wedge-type anchor bolt, nor do I know just how deep you can drill into
this post.

Cheers,

Roger.


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