Lipo expansion?
 

This is probably a pretty newbish question, but I'm new to lipos and this is my first time encountering a problem that made me think about it. But do lipo's expand during use, due to heat, charge etc.? Or is that only when they "puff"(is that the term?)? I ask, because I'm building a setup to which, my 3S soft packs, will be a very tight fit. And I can only create so much space before I would have to build a new chassis, which I don't want to do, since it's a "vintage" truck. So any wisdom would be appreciated. Thank you for your time :)

Lipos should never puff if they feel swollen or soft and puffed they are shot.
Never make your lipo get to 140deg and make sure you buy the right rated lipo C rating for your aplication the higher C rating the more amps it can handle always try and get the highest C rating you can.

The only time lipos seem to get warm is in 1/8th buggys where there's limited space and they're are pushed hard due to racing conditioins. Normally in a MT or other surface RC, they don't get much more than warm. If yours are getting hot, they've been undersized electrically - when lipos get hot, that's a sign they're struggling to keep up with the amps demanded by the setup.

Amps supply is more than just C rating, lipo capacity (mah) is also part of it. Usually a 5000mah lipo with 25C or more will usually keep up with the most demanding setups.

Properly sized for teh amp demand, lipos will be dimensionally 'stable'. They def should not puff. Don't get that confused with some lipos that swell slightly on discharge and then return to normal when recharged.

Thanks for the replies. I wouldn't know if it's going to get hot or not, as i haven't even charged them yet. I just noticed that the space is so tight in my SRT for the 3S(yet my 5S hardcase fits perfectly :rolleyes: ) that they would have no room for expansion. I just wanted to make sure the packs wouldn't be any bigger during use or charge, as there is no room to accommodate growth and I didn't want to create that pressure within the packs.