patternrules

My Feedback: (6)

I noticed that no one this year at the Nat's, using gallon ziplock baggy's of sand or Pyrex dishs for charging, do you guys have this down so good that it's not necessary now????

Strong JD

My Feedback: (10)

Its probably still a good idea, kinda like having someone to hold your plane while you crank, but not entirely nessicary. I've charged lipos in excess of 300 times without ever having one even get warm, but thats just me. Most troubles begin when folks push charging limits or a malfunction of some sort occurs, (rare). Kinda like the safty issue of a battery on a gallon of fuel for the pump to pump glow fuel, that one never made a lot of sense to me. Most all problems EL. and otherwise results from human error of some sort, most, but not all the time.
Jamie Strong

can773

My Feedback: (1)

I dont charge in a container of any sort, but I am within sight/sound of the packs while charging. The nice thing about the TP balancer is it provides an audible alarm if any cell hits 4.3V.....if you hear that during charge you unplug the pack. The problems arise when you a) make a mistake during charge setup with cell count, or b) allow an overcharge (read imbalanced pack) situation to remain unchecked and the pack to continue charging.

Again with most stuff on the big electrics, attention to detail is paramount. Personally I have not found lipo charging to be of significant danger, its not like the packs explode instaneously....it takes a bit of time for an overcharge situation to progress to one of fire.

My biggest concern is one where a model crashes, the pack shorts and ignites. Where I live and fly grain fields are plentiful and the climate is very dry, an ignited pack in a farmers field could turn into a wildfire within a matter of minutes. Coming from a farm I have witnessed first hand what a burning crop that gets out of control can turn into on a windy day !!

FLYERSG

While most lithium fires result from human error (overcharging, physical damage, shorting the leads, excessive current flow, etc.), there is a small percentage of cells which contain manufacturing defects. Those cells are unpredictable which is one reason why a lithium pack should never be left alone while charging. In addition, if you have a suitable charging container, it makes good sense to use it. I have a 5S3P pack which is brand new....has never been used and doesn't even have a connector soldered to the leads. Yet, it's puffed which indicates it may have been damaged when the pack was built, or there are one or more defective cells in the pack. Clearly, the balancing modules such as those which are available from Thunder Power offer one more step toward safer electric power. I've been reading various electric forums on the Internet for several years now and many of the problems modelers experience with lithium polymer batteries occur when folks become complacent and fail to follow the safety rules.

Mike Moritko