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Discussion Starter #1
Need an opinion.

In June I bought a pack of sixteen US125's. (6v. deep-cycle) I now have 700
miles on the pack. I use a PFC20 for charging.

I have questions about two of the batteries and would like an opinion as to
whether I should ask for a replacement of them. (I don't want to "forget
about it" and later wish I had, but on the other hand, I don't want to look
like an idiot, either.)

After normal charging and a twelve hour rest, here are the voltages:

BAT VOLT DEV.
#1 6.63 +.02
#2 6.55 -.06 LOW
#3 6.61 0
#4 6.63 +.02
#5 6.64 +.03
#6 6.62 +.01
#7 6.59 -.02 TERMINAL LEAKING
#8 6.62 +.01
#9 6.61 0
#10 6.60 -.01
#11 6.59 -.02
#12 6.61 0
#13 6.60 -.01
#14 6.60 -.01
#15 6.62 +.01
#16 6.62 +.02

I don't think there is any question about #7.

#2 had always been low. I've done an individual charge on it and it back
comes up, but after the next drive/charge cycle, it's back down again. Is
the enough of a problem to request a new battery? (I don't want to look like
an idiot, if this is in normal parameters.)

Roger Daisley
Pullman, WA
[email protected]

Ps: Getting a good solid 45-mile range. (VW Cabriolet.
http://www.96-volt.com

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Discussion Starter #2
Hello Roger,

Get the #7 replace or any other positive post that looks like a dark brown
color. Do not accept any new battery that has these dark post. This is a
sign of a poor post seal. At the dealer, before I accept a battery, try to
get the latest manufacture date or the same date as the existing ones.

Yours are only about 3 months old from the dealer, but the manufacture date
may be older then that. Have them prorated from the date you purchase them.
They may be a 12 to 24 months free replacement anyway.

Then check the voltage and then do a load test to see how much it will drop
that will match the voltage drop of your other existing batteries.

Check the specific gravity of the #2 battery to see how if they match the
other batteries. If it does not match then the electrolyte may be diluted
by adding water to a low cell that maybe was not fill up all the way and was
reading a specific gravity of 1.275 at the beginning.

If the specific gravity matches, then get the #2 battery replace and tell
them you perform a load test on it, which drops off faster then the rest.
Driving your EV performs the load test. Perform the same load test on this
battery and the new replacement at the same ampere you would have on it
while driving the EV after its been charge to the same level as the others.

Do not have them perform a load test on a fully charge battery, even a bad
battery that is fully charge may show good for only a 15 second load test.
It is best to perform this load test on a 40 to 60% DOD battery.

I am now running 30 T-145's for 6 years now and before I balance charge, I
read them at 40% DOD which two of them are 0.05 volts difference. For me,
this is not critical, because I do not have to squeeze every bit of range
out of these batteries for the distance I am driving.

It is normal for batteries to be about 0.05 volts out of balance after 6 to
10 years. I normally replace the whole pack when they start to get 5% out
of balance or about 0.3 volts.

Roland




----- Original Message -----
From: "Roger Daisley" <[email protected]>
To: <[email protected]>
Sent: Tuesday, October 09, 2007 4:50 PM
Subject: [EVDL] Need opinion on battery repacement


> Need an opinion.
>
> In June I bought a pack of sixteen US125's. (6v. deep-cycle) I now have
> 700
> miles on the pack. I use a PFC20 for charging.
>
> I have questions about two of the batteries and would like an opinion as
> to
> whether I should ask for a replacement of them. (I don't want to "forget
> about it" and later wish I had, but on the other hand, I don't want to
> look
> like an idiot, either.)
>
> After normal charging and a twelve hour rest, here are the voltages:
>
> BAT VOLT DEV.
> #1 6.63 +.02
> #2 6.55 -.06 LOW
> #3 6.61 0
> #4 6.63 +.02
> #5 6.64 +.03
> #6 6.62 +.01
> #7 6.59 -.02 TERMINAL LEAKING
> #8 6.62 +.01
> #9 6.61 0
> #10 6.60 -.01
> #11 6.59 -.02
> #12 6.61 0
> #13 6.60 -.01
> #14 6.60 -.01
> #15 6.62 +.01
> #16 6.62 +.02
>
> I don't think there is any question about #7.
>
> #2 had always been low. I've done an individual charge on it and it back
> comes up, but after the next drive/charge cycle, it's back down again. Is
> the enough of a problem to request a new battery? (I don't want to look
> like
> an idiot, if this is in normal parameters.)
>
> Roger Daisley
> Pullman, WA
> [email protected]
>
> Ps: Getting a good solid 45-mile range. (VW Cabriolet.
> http://www.96-volt.com
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
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