[Cascade]

We think we had one battery fail this year as well. We will be testing this again in a couple weeks. We left this battery at home so as not to get it confused and put in the robot.

Please see the attached battery testing we did between the 2006-2007 seasons. Please keep in mind the data presented is based on the old Exide batteries; however, I imagine the new MK batteries will respond in a similar way. We use this in the pit to estimate when a battery will be fully charged based on the charging voltage. If you have any questions, we are happy to answer them.

About the two chargers teams are using: The old charger with the single LED was a pain to use until we understood them. When we tested the batteries we had a current meter in series with the charger and battery to see what the charger was doing during the change in color from amber, to green, to blinking. Amber means the battery is charging. As you can see from the graph as the voltage goes up, the charging current goes down. A solid green light means the battery is charged. This occurs at 14.2 vdc like clockwork. The blinking light back to amber to green means the charger has entered a trickle charge mode. You can see this happen on the current meter as the meter will momentarily show current then go back to zero. The blinking coincides with the momentary current shown on the meter.

The new charger is better since it shows the percentage of charge. It is a little quirky on startup and you do have to make sure to hit the current button twice to get to 6 amps and if the red light is lit unplug the charger and plug it back in. By the way, you can also see from the graphs, no charger is actually applying 6 amps to any battery.

Other tips we have learned the hard way:
1. Put Anderson connectors on your battery charger leads. This prevents arc welding in the pits and gets you a 100% good connection every time. Think we have post on this through my handle.
2. Make your own battery cables. We have a post on this you can find, too. This tip has eliminated battery cable problems for us.
3. Carry batteries by the battery, not the cables. Take care of the cables, also.
4. Be nice to batteries and treat them like a laptop or your favorite tool.
5. Check to make sure the spring that clicks onto the pin in the Anderson connector is engaged. We found one had slid off the spring and not making full contact with its mate on the robot end of the Anderson connector. To fix this, simply push or poll the cable until you hear or feel the click of the pin snapping back onto the flat spring.
6. Clean any corrosion from the battery posts or cables and make sure everything is tight.
7. Buy a load tester. We got a cheap one at Harbor Freight Tools for about $20. Don't forget to use a DMM to measure battery voltage.

Feel free to use our battery information or share with other teams as you wish.