I BOUGHT A ELITE ULTIMATE AND A 4100 MOTOR. BOUGHT THE WHOLE WORKS FOR MYSELF. A KID THAT RACES PYLON WITH US BOUGHT THE SAME THING EXCEPT THAT HE BOUGHT A 5100 MOTOR I THINK. ANYWAYS, HE ASKED TO BORROW MY NEW BATTERY, LITHIUM POLYMER AND CHARGED IT WITH MY ASTROFLIGHT LITHIUM CHARGER. HE FLEW IT AROUND AND THEN AFTERWARDS, CHARGED IT AGAIN. I WAS NOT PAYING ATTENTION AS TO WHAT WAS GOING ON. ABOUT 3/4 THROUGH THE DAY, HE COMES UP TO ME AND SAYS THAT MY CELLS ON MY BATTERIES HAVE EXPANDED TO TWICE THE SIZE. WHAT SHOULD HE DO. WELL I TOLD HIM TO LET IT SIT FOR A LITTLE BIT AND WELL FIGURE IT OUT ( OUT IN THE DIRT OF COURSE AWAY FROM EVERYTHING ) . wE COVERED THE BATTERY SO THE SUN DID NOT BEAT ON IT. ABOUT A HOUR LATER ALL THE CELLS HAD EXPANDED.

MY QUESTIONS IS, IS THIS NORMAL FOR THIS TO HAPPEN, HAS ANYONE HAD THIS HAPPEN AND WHY DOES IT HAPPEN. I AM NOT SURE THE CIRCUMSTANCES OTHER THAN I BOUGHT A NEW BATTERY 1320MAH AND NOW IT IS NO GOOD. SO I AM OUT $70.00 NOW.

I KNOW HE WAS CHARGING AFTERWARDS AT 1.3AMPS . COULD THIS BE THE WHOLE ISSUE. I KNOW HE HAD ABOUT 3-4 FLIGHTS THAT DAY.

ANY HELP WOULD BE APPRECIATED.

Kevin,
How many cells (3S or 2S?) What was his gearing and prop? Do you know how many amps he was pulling? 1.3 ah charge rate is correct for that pack. I doubt it was charging. Had to be either discharging at a higher rate (too many amps) or a fault with the pack. Contact Thunderpower and send them some pictures with an email.

-Mike

THIS WAS A 3 CELL PACK.

IT WAS A 5100

6:1 GEARING

12x 6 PROP

CASTLE CREATION 10

He was pulling about 15-16 amps on that pack rated at ~13 amps. I run the 5100kv 6:1 on a 9X4.7 and it is pulling 11.5 amps. Here is a wattmeter shot showing the amps on what your friend was running. That would do it.


-Mike

Moral of the story: Never lend expensive LiPoly battery packs to your "friends" unless you know his setup isn't going to overload them.

I think he owes you a replacement pack because he wrecked it.

ALL TAKEN CARE OF.......GOOD FRIENDS TAKE CARE OF GOOD FRIENDS

# 1 ISSUE BEING NEW TO THE ELECTRIC STUFF IS THERE REALLY IS NOT ANY INFO ON THIS STUFF. I WENT OFF WHAT THREE HOBBY SHOPS HAD TO SAY. WHEN I PURCHASED MY ORIGINAL SET-UP, I WAS SOLD ALL THE WRONG STUFF. WENT TO ANOTHER SHOP THEY SOLD ALL TYPES OF ELECTRIC STUFF BUT HAD NO ONE WITH KNOWLEDGE. JUST A KID THERE THAT WAS A "BUMP ON A LOG". THE THIRD WAS A ALL ELECTRIC SHOP THAT SOLD ME MY MOTOR AND SETUP. I HAVE THE 4100, (HAD THE 3120MAH PACK ) AND A CASTLE CREATIONS 25.

IS THIS SETUP THAT I HAVE ANY GOOD????? I HAVE TO BUY ANOTHER BATTERY PACK. WHAT SHOULD I BUY. I ALSO HAVE THE ULTIMATE BY ELITE. WHAT PROP AND ALL THAT GOOD STUFF. WE ALREADY HAVE SEVERAL FRIENDS THAT WANT THEM BUT AFTER THE LITTLE EPISODE, THEY ARE UNSURE ABOUT BUYING THINGS...

I THINK INFO AND SCENERIOS ARE IMPORTANT BECAUSE SOMEONE WILL GET HURT EVENTUALLY.

The info is out there. You just have to look for it. It's definitely tougher with electrics because there are so many different variables, and so many good solutions to each problem.

I myself just got an Eflite Ultimate last Friday. The instructions outline what should be a good power setup for it. IIRC, an Eflite Park 370 motor in the stock gearbox with the stock prop on a 3S LiPoly. You've got the Park 370, right?

That LiPoly pack was just fine. Your friend unknowingly ABUSED it. That's why it puffed up. He was drawing more Amps than the pack was designed to take. Don't hesitate in getting another pack, just be more careful next time, and ASK here first. Better yet, get yourself an Astro Whattmeter or similar tool so you can test a setup before you go flying. A few seconds of overload won't hurt a battery.

As Matt pointed out...get a Wattmeter. That is the single most important peice of equipment for electrics. It can save you hundereds.
The setup you have is a good one. As a matter of fact...they are all good as the possibilities for gearing, propping, and powereing are almost endless.

The 4100 geared 6:1 on a 3S and 12X6 should yield about 13 amp WOT. I would stick with the 1320 Thunderpower batteries as they are perfect for this app.

Glad to hear it worked out for you and your friend. And as Matt said...ask here first and dont rely on the guys at the Hobby shops. 99% of them only know what they read on the side of the box. There is real world data in the forums.

-Mike

thanks guys.....

i will get another pack and a wattmeter....

i will be back with more questions later...learning never ends.

I know this an old post, but im new to lipo and am going through the posts for info.

Can i just second the advice on not listening to the LHS guys, ive wasted more money from bad advice than i care to remember (probably enough for a good complete set up [:@]). Take the time to look around here (other good forums also available ) At least we can asume the people here are at least flying - For all i know the LHS guy might just be there for there pay packet!!!. and ask no matter how dumb you think you sound - we all began somewhere and have had the same problems. I totally recommend research and online purchasing but ONLY when you know what you want.

Sorry LHS

Allthough i do love looking around them and seeing stuff in the "flesh"

my 0.02p's worth

Joseph