Absolutely DO NOT charge FRC batteries at a rate of greater than 6 amps. The batteries will be permanently damaged and may go into a severe failure mode while charging.
The max charge rate is 6 amps. The IDEAL charge rate for these batteries is 2 amps.
We use this charger. It charges 10 batteries at a time, at a sweet 2 amp rate. Keeps them in good shape.
http://batterytender.com/telecomm-st...12v-at-2a.html
You are much better off buying more batteries and charging them at the ideal rate rather than destroying batteries and creating safety hazards from ruptured batteries.
BTW - on a related subject everyone should replace the alligator clips on their chargers and use Anderson SB connectors to plug into the battery.
Yesterday I saw a team connect a charger with alligator clips into the SB50 connector, the clips touched each other, welded themselves together and turned WHITE HOT. It was an amazing site to see but this exercise is better left to Adam and Jamie on Mythbusters, not a FIRST pit.
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