# Maintain those battery terminals



## teverth (May 18, 2009)

A quick reminder to always keep your battery terminals in top shape.

I did not and the result was a loud bang and an exploded battery . 

Here is why: A loose or otherwise not ideal connection between your cables and the battery will develop resistance. And according to Ohm's law that means that power is dissipated at the connection instead in your motor.
Ohms law: U = R*I -> Watt = U*I = R*I^2 
For example a 300A current would at say 0.01 Ohm resistance result in 900 Watt of power being dissipated at the battery terminal!! That's a lot for a battery terminal to absorb! 

In my case the lead of the terminal melted and dropped into the battery after melting the plastic battery case. 
A subsequent spark inside the battery led to a loud explosion which popped the battery filler caps and also shattered the top of the battery itself.
Luckily the main body of the battery stayed in order and the acid was retained... Could have been worse!


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## luch (Apr 21, 2009)

Yup!!!. The golf cart melted a bolt-down cable end into the battery case today. I poured water on it and it boiled. Then after 10 min I pressed on the GO peddle and the cell cover blew up and off the battery. It bounced off the bottom of the bench seat . Lucky I had the bench seat down..From now on I'm gonna run 15 min then use my Harbor Fright non contact Infrared thermometer to spot check all the cable connectors. If they gets somewhere around 15 degrees over average terminal temp I'm putting a new sweat solder pure copper connector on. Ye Gads I hope none of us ever gets a plasma fire. If so yank hard on the batt disconnect/pilot eject ring.


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## teverth (May 18, 2009)

luch said:


> ..From now on I'm gonna run 15 min then use my Harbor Fright non contact Infrared thermometer to spot check all the cable connectors. If they gets somewhere around 15 degrees over average terminal temp ....


What a brilliant idea. Temp change is probably one of the most reliable measurements of connection trouble!


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## rmay635703 (Oct 23, 2008)

Since we're on the topic of terminals what is the best way to "repour" a melted and overcleaned terminal that is down below the stud threads?

I was thinking of making a simple form and using a plumbers soldering iron and solder to reform and build up the terminal, any ideas?


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