Boe-Bot Battery Pack Meltdowns - In case you have a problem

Ken Gracey

Hello,

We've had a few Boe-Bots with melted battery packs this last summer.

In case you're aware of one or need more information, please review http://www.parallax.com/news/2014-09-05/melted-boe-bot-robot-battery-pack-our-behind-scenes-research-find-source-elusive

Ken Gracey

xanadu

Definitely a short. I had plastic around a spring melt once, just like page 6 example A shows. - (PDF) http://www.parallax.com/sites/default/files/downloads/Boe-Bot-Battery-Pack-Issue-Report-0814.pdf

I can confirm it was due to placing one battery in reverse polarity. I have done this twice over the years, it gets hot pretty quick.

I have also wondered about that metal pan head screw hitting the neg side of the battery, that seems like the next most likely cause to me...

Martin_H

I've shorted Vbat to Vss twice. Once on my CBA robot, but it has a polyfuse which tripped, but the voltage regulator got hot before it did so. The second time was on a complete homebrew bot and I partially melted the battery holder. I really should use polyfuses more often.

Genetix

Ken, might I suggest that when the BOE is redesigned that the Vdd header should become red (power), the Vss header should become green (ground), and the 2 headers have a gap between them.

Whit

Ken - I read the pdf report earlier today. Though the problems seems to be a short - I appreciate how much attention and study you all have put into the reports of a problem. In my mind this is just another example of Parallax's excellent customer service and the company's great care of the Educational market. Thanks for all you guys do!