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View Full Version : A cautionary tale and cheap solution


GeraldRosebery
08-29-2005, 09:13 PM
While charging a NiMH 3300 mah pack at C in the florida sun with no breeze at all and relative humidity the Florida August normal I managed to get the middle of the pack up to 240F. I thought I had got away with it until I saw the leaking cells the next day.

What to do - I "borrowed" a stainless garbage can from work (surplus anyway) and mounted on it two 5" surplus 12V computer fans ($10). These draw only 4W in total and move a lot of air for that. Now I charge with the packs in the can and the air flow keeps LiPos, at ambient temperature and NiMh's to a perfect for use 140F. Cheap and simple. Write for photo if you are interested. I don't seem to be able to add one here

grosebery@cfl.rr.com

Matt Kirsch
08-30-2005, 02:14 AM
The pics have to be pretty small if you want to attach them.

Twmaster
08-30-2005, 03:48 AM
I built something like that for my battery packs when I was racing electric boats. Was simple and CHEAP. Take a standard 4" computer fan (had like 20 of then from scrap PeeCees), get some of the foam board that gets the foamy flyers weak in the knees, cut 4 pieces to make a box around the fan. Glue in a couple of perches so the packs can stay up in the airflow. Chillin baby.

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Mike N