DIY Electric Car Forums banner
1 - 3 of 3 Posts

·
Registered
Joined
·
70 Posts
Discussion Starter · #1 ·
With the eco-escort (details below) I am experiencing melted battery posts.
The first time it I found one, I thought it was actually a broken battery
post from cable strain that then melted due to sparking at the now loose
connection, but I've since concluded that the posts are somehow being
overheated and melting.



I've had 4 now. It's always a negative post. It can be anywhere in the pack.
It does not appear to be related to the quality of the cable connection. My
theory is that this is happening either during charging, or during use. I
use the vehicle to commute approximately 12 miles (one way) to work.
Although range is sufficient for a round trip, I usually charge at work and
at home. I do drive over some hills, so much of the time I am going full
throttle. In fact, I'd say that most of the time I am either full throttle,
or coasting.



My plan for testing is to drive the car (with a smaller traction pack now)
under these conditions and test for heat at the batter posts both right
after driving and during charging.



Does this seem like a reasonable testing plan?



Does anyone have any experience or insight that would point to one cause or
the other?



Thanks.



Greg



Components:

Motor: ADC 9" FB1-4001A

Controller: 750 amp Logisystems 120AFX

Batteries: John Deere OEM version of Exide E-3600

Charger: Russco SC 18-120 SO - this was purchased around 2003



More detail can be found at
http://home.windstream.net/relytgerg/ecoescort.html and
http://www.evalbum.com/2695

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.sjsu.edu/mailman/private/ev/attachments/20100905/cd81f899/attachment.html
_______________________________________________
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter · #2 ·
Hello Greg,

Installing and testing out your battery pack, it is recommended to torque
the battery connections as per specifications of the battery manufacture.
In my case it was 75 inch lbs for heavy duty zinc plate copper battery clamp
for a standard auto post.

Initially torque to this value, the battery clamp will not fully 100 percent
contact all the surfaces of the battery post because of the pre-cleaning
with a battery brush that leaves micro small valleys and peaks on the
surface of the post.

Therefore every time you put a load on these battery terminals, this small
peaks will melt down which will cause a less torque value. This is what is
call Shrink Back.

Therefore drive the EV under load for the first five miles and re-torque
again. I have found that I may lose about 5 inch lbs in the first 5 miles
drawing a average of 200 battery amps. Drive another 5 miles and re-torque
again. The torque lost will get less each time. When the torque lost is at
about 1 inch lbs or less, then you can check the torque value in 30 days and
you can determine what the next lost will be.

Some battery manufacturers put a torque range of like 60 to 75 lbs, so make
sure you re-torque when the torque gets to the minimum value.

If a set of batteries are flood type, take a specific gravity reading before
you start the first 5 miles and then after each 5 miles. You can then
determine what the estimate range of the EV over a set number of miles.

The problem with a torque wrench, is that there are not insulated, where the
handles can bridge the battery post. To prevent this from happening, I
first set the torque value a inch lb torque wrench and then I slip over a
soft rubber hose with one end seal up. It is best to get a 1/4 drive torque
wrench or use a 1/4 inch to 3/8 inch adapter on a 3/8 drive torque wrench.

Roland


----- Original Message -----
From: "Greg Tyler" <[email protected]>
To: <[email protected]>
Sent: Sunday, September 05, 2010 10:44 AM
Subject: [EVDL] Melted battery posts


> With the eco-escort (details below) I am experiencing melted battery
> posts.
> The first time it I found one, I thought it was actually a broken battery
> post from cable strain that then melted due to sparking at the now loose
> connection, but I've since concluded that the posts are somehow being
> overheated and melting.
>
>
>
> I've had 4 now. It's always a negative post. It can be anywhere in the
> pack.
> It does not appear to be related to the quality of the cable connection.
> My
> theory is that this is happening either during charging, or during use. I
> use the vehicle to commute approximately 12 miles (one way) to work.
> Although range is sufficient for a round trip, I usually charge at work
> and
> at home. I do drive over some hills, so much of the time I am going full
> throttle. In fact, I'd say that most of the time I am either full
> throttle,
> or coasting.
>
>
>
> My plan for testing is to drive the car (with a smaller traction pack now)
> under these conditions and test for heat at the batter posts both right
> after driving and during charging.
>
>
>
> Does this seem like a reasonable testing plan?
>
>
>
> Does anyone have any experience or insight that would point to one cause
> or
> the other?
>
>
>
> Thanks.
>
>
>
> Greg
>
>
>
> Components:
>
> Motor: ADC 9" FB1-4001A
>
> Controller: 750 amp Logisystems 120AFX
>
> Batteries: John Deere OEM version of Exide E-3600
>
> Charger: Russco SC 18-120 SO - this was purchased around 2003
>
>
>
> More detail can be found at
> http://home.windstream.net/relytgerg/ecoescort.html and
> http://www.evalbum.com/2695
>
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL:
> http://lists.sjsu.edu/mailman/private/ev/attachments/20100905/cd81f899/attachment.html
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> | OTHER HELP: http://evdl.org/help/
> | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter · #3 ·
The six volt golf cart E3600 batteries are made for golf carts. Golf
carts use a much lower running current than EV's and most use #6 wire
connected to 5/16 inch battery studs.

In an EV application, wire lugs connected to these studs will loosen up
and the high current will heat up the post and result in a meltdown.

Unfortunately, most GC2 golf cart batteries are readily available with the
studs. Interstate, Trojan, US Battery, Sam's Club all have them. EV use
requires either the L post with the hole or the standard round tapered
tall AP, automotive post. Trojan and US batteries may be special ordered
with these desirable post.

However, most resellers of GC2 batteries don't want to special order
batteries with the L or tall AP post. They wish to sell what they have in
stock. So, insist on the proper post.

If your batteries are already equipped with the L or tall AP post, please
disregard the above and read the excellent answers to your question posted
by others.


Russ Kaufmann

RUSSCO Engineering

http://russcoev.com

The Other PFC Charger With Built In GFCI


> With the eco-escort (details below) I am experiencing melted battery
> posts.
> The first time it I found one, I thought it was actually a broken battery
> post from cable strain that then melted due to sparking at the now loose
> connection, but I've since concluded that the posts are somehow being
> overheated and melting.
>
>
>
> I've had 4 now. It's always a negative post. It can be anywhere in the
> pack.
> It does not appear to be related to the quality of the cable connection.
> My
> theory is that this is happening either during charging, or during use. I
> use the vehicle to commute approximately 12 miles (one way) to work.
> Although range is sufficient for a round trip, I usually charge at work
> and
> at home. I do drive over some hills, so much of the time I am going full
> throttle. In fact, I'd say that most of the time I am either full
> throttle,
> or coasting.
>
>
>
> My plan for testing is to drive the car (with a smaller traction pack now)
> under these conditions and test for heat at the batter posts both right
> after driving and during charging.
>
>
>
> Does this seem like a reasonable testing plan?
>
>
>
> Does anyone have any experience or insight that would point to one cause
> or
> the other?
>
>
>
> Thanks.
>
>
>
> Greg
>
>
>
> Components:
>
> Motor: ADC 9" FB1-4001A
>
> Controller: 750 amp Logisystems 120AFX
>
> Batteries: John Deere OEM version of Exide E-3600
>
> Charger: Russco SC 18-120 SO - this was purchased around 2003
>
>
>
> More detail can be found at
> http://home.windstream.net/relytgerg/ecoescort.html and
> http://www.evalbum.com/2695
>
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL:
> http://lists.sjsu.edu/mailman/private/ev/attachments/20100905/cd81f899/attachment.html
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> | OTHER HELP: http://evdl.org/help/
> | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
>
>


_______________________________________________
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
 
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top