dannyk
Trying to charge 7.2v VEX batteries on a smart charger from BEST kit. Light on charger starts green despite battery not charged. 6.7v according to the voltmeter. No change with fast vs safe. 30 minutes searching and cannot find an answer on VEX site, VEX forum and general search. Supposedly the smart charger will continue to trickle even when it registers a charged battery. We have 3 batteries, one is charging normally (light starts red and turns green when charged) and the other 2 have this problem (charger light starts green and battery doesn't charge), no change in the voltage after an hour on charger.
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jgraber
Light on charger starts green 
That means the battery is not making connection.   
If another battery works on that charger, then it is probably the connectors on the bad battery.
Try wiggling the battery wires/connector when using voltmeter, and when using charger.
You could also try connecting the battery and charger, while charger is unplugged, and use a needle to pierce the charger battery wires to check the voltage on the battery that way.  Also try that without a battery charged as well.  You may have to discharge the charger output capacitors with a load of some kind first.  Don't try it if you don't understand what I'm talking about...
 Does the battery have power poles, or standard white connectors?   
Sometimes the battery wires come unwelded at the battery end also.

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dannyk
As usual, you fixed it. The VEX people said the batteries were bad. Thanks for saving us $60. 
So the battery wire connections were fine but when I pushed the wire going into the powerpole connector of the molex/powerpole adapter it clicked and the charge light turned red. Still not sure why one battery charged fine and the other 2 didn't (I even rechecked it and the one battery charged fine with the loose connection) but we are back in business.
Thank you again.
Danny
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