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View Full Version : Lesson Learned about cold temps


Steven Kautz (SVEN)
02-25-2008, 09:29 AM
I am sure all the veteran Li-po users know this as common knowledge, but for those like me who are new to Lipo packs, I thought I would share my experience this weekend.

I have been using an 1100 pack in my 2.2 crawler for the past couple weeks and it has been performing very well. I am a Li-po newbie, having only used them for about 2 months. This past Saturday SERCRC had a competition in Alabama and the temperatures were in the freezing range. I ran the first course in a little over 4 minutes and came out with a nice score of 0. I figured I would just run the next course with out charging. I had been getting 30-40 minutes of play time previously, so I wasn't too worried about it. So my truck sat outside while I waited about 30 minutes to start the next course. When I did start the second course, I got past the 2nd gate and the truck felt dead. I was clueless as to what the problem was. I took a repair penalty (10 points) and put an 860mah pack in the truck to finish running the course. I ended up pointing out and got a 33 for the course, which put me out of a chance at the Finals.

After the run I charged up the 1100 still thinking it was just a dead battery. When it finished charging it had only put in 300mah, so I ask MaxAmps team mate Jeff Williams what was up and he told me it was the cold temps affecting the pack.

So hard lesson learned, keep your packs warm before a run in the cold.
I drove the 1100 on Sunday and it performed very well when I drove through the courses again. It was sunny and about 55 degrees out side.

Jason Maxamps.com
02-25-2008, 10:02 AM
Yup they loose a lot of their rated capacity at lower temps. I fly a lot in the winter and start with warm packs and keep my spares in my pockets. I have heard of guys putting those hand warmer packets inside a small sock and then putting that with a pack in thier coat pocket. Use caution when doing this those hand warmers can get hot.

Jason

Steven Kautz (SVEN)
02-25-2008, 11:06 AM
Doh! I had some of those hand warmers with me. I should have done that. Oh well, it's hindsight and I will know better next time.

Rick Findley
02-25-2008, 01:26 PM
Appreciate the reminder! Gotta watch the ambient temps to when charging. Had some of my older packs balk at charging at low temps too!

In the summer (Arizona), using the temp probe, if the ambient temperature gets above your max temp on your charger cutoff, then you ain't gonna charge it either!