MK Battery Problems

[Al Skierkiewicz]

Mitch,
The spec is 11mOhm nominal so I wouldn't be too worried even up to 15 or 20 mOhm. However 5 ohms is way too high. I know the construction of this battery does make it possible to damage the terminal inside the red/black coating at each terminal. Picking up by the wire is a guaranteed failure.

[Brandon Holley]

Just to reiterate, team 125 had 2 bad batteries go down on us at the boston regional.

One was from 2007 KOP the other from 2008 KOP. Other than that I dont have the exact details from them, however when put under load (with a load tester) we got a reading around 9 V for both of them.

[dez250]

Brandon, when you use the load tester on an "in working order" battery, what is the "regular" reading you would get?

[Tom Bishop]

Our 2 batteries from the 2007 KOP act like they have take a charge then when you put them on the robot the voltage immediately drops. I haven't load tested them, but we just don't use them now. They went dead while we were using them on our 2007 bot to practice in the fall. They've been charged on both a NAPA charger and the new Schumaker.

[Starke]

To test the theory of a bad batch of batteries, here is the lot number for the bad batteries that SparX had.

Lot Number: 061009D

[RyanN]

We dropped one of our batteries from last year. The little plastic strip on the top of the battery came loose, giving access to the cells. Later, that battery tipped over somewhere, and the acid poured out of it. When this happened, it still has 12V on the posts, but when we tried to move, it would reset the controller. Obviously, if there is a problem with a battery, then its either the posts or one or more of the cells.

[EricVanWyk]

Originally Posted by RyanN

We dropped one of our batteries from last year. The little plastic strip on the top of the battery came loose, giving access to the cells. Later, that battery tipped over somewhere, and the acid poured out of it. When this happened, it still has 12V on the posts, but when we tried to move, it would reset the controller. Obviously, if there is a problem with a battery, then its either the posts or one or more of the cells.

Please do not continue to use a battery that has leaked. Please.

[Gdeaver]

Team 104 had battery problems at the NJ regional. The 2 2008 and 1 2007 batteries failed on Thurs. They would charge but would be down half way through a match. Any battery that was charged on the 2008 charger failed. We made it through the regional on a 2006, 2007 battery and the 2006 and 2007 chargers. We are sure the common mode of failure was the 2008 charger.

[RyanN]

Originally Posted by EricVanWyk

Please do not continue to use a battery that has leaked. Please.

We didn't realize that it leaked until we pulled it off the robot and I tried to figure out why it wasn't working. I knew the plastic plate on the top was loose, but I did not know the black rubber plug had come lose. I'm not sure if it leaked or it evaporated while charging. We disposed of the battery properly, and it is now in the battery graveyard.

[metR]

At the boston regional we had some trouble with our charger. We would plug in one of the batts to charge, and come back later and the red "Check" light would be on. Unplugging the battery from the charger and charger from the wall solved the problem, but it did this at least twice. This caused trouble when we thought the batteries were charging, but were just sitting instead. We have the 2008 KOP charger and batteries.

[IndySam]

Originally Posted by Gdeaver

Team 104 had battery problems at the NJ regional. The 2 2008 and 1 2007 batteries failed on Thurs. They would charge but would be down half way through a match. Any battery that was charged on the 2008 charger failed. We made it through the regional on a 2006, 2007 battery and the 2006 and 2007 chargers. We are sure the common mode of failure was the 2008 charger.

We had 2 of our 2007's fail. We did not use the 2008 charger, our batter cart has 6 of the old style chargers on it.

BTW 2006 batteries were illegal for competition this year.

[MrForbes]

Originally Posted by Gdeaver

Team 104 had battery problems at the NJ regional. The 2 2008 and 1 2007 batteries failed on Thurs. They would charge but would be down half way through a match. Any battery that was charged on the 2008 charger failed. We made it through the regional on a 2006, 2007 battery and the 2006 and 2007 chargers. We are sure the common mode of failure was the 2008 charger.

THe new chargers are a bit tricky, you have to make sure the voltage is set correctly, and current is set correctly after you connect the battery.

[Chris Fortmeyer]

Originally Posted by fatjoe3833

Mark, was the second battery from spare parts okay? Maybe there was a problem with the chargers at SBPLI. I saw the spare parts people charging the extra batteries troughout Saturday. Maybe the batteries were abused or mishandled at another regional.

-Joe (Elimnation Match Spare Battery Guy)

Joe,

I am actually the member of the drive team that noticed the bad battery from Spare Parts. The robot was continually resetting and not staying on long enough to even get a voltage reading on it. The second battery from Spare Parts seemed to work fine, even though it was not fully charged at the beginning of the match.

[Gdeaver]

We were not the only team having battery problems. Yes we were aware of the need to set the battery charger. I can't prove the 2008 charger was the problem. All I can say is that the batteries that were cycled on the 2008 charger failed. The ones which were not worked fine. As to the 2006 battery legality. We used what we had. We were not the only ones.

[ebarker]

Originally Posted by squirrel

Just to keep things interesting, I'll mention that we discovered that the Andersen connectors this year are made differently from past years, and that we could get the power to the robot to go on and off by merely wiggling the Andersen connector with the new batteries, but it would stay working with the old batteries (which have the old connectors).

What was different about the connector ? Were the pins inserted into the shell correctly ? I'd like to see this thing ? Going to Atlanta ?