Expanded NiMH Cell? - RC-Monster Forums

rawfuls · **Expanded NiMH Cell? -** 03.16.2009, 12:11 AM

I think one of my cells just expanded, and was wondering if I need to toss the pack right away, or if I can keep using it.
It only expanded barely.
It was the end negative cell.

A little part of the cell wrap shrinked off.

Any help linc?

E-Revonut · 03.16.2009, 12:43 AM

Get rid of that cell, rest of the pack is prolly still useable

rawfuls · 03.16.2009, 12:49 AM

Darn, I don't have a use for a 5cell pack =/

E-Revonut · 03.16.2009, 12:53 AM

RX pack that never dies!

rawfuls · 03.16.2009, 12:53 AM

Haha, too bad I don't run RX packs.
Should though.

Would be fun to see how long it'd run for.

Especially since it's a 5k pack :O

EDIT1:
So if I attempted to charge the pack, would it go boom?
Or at least start smoking?

E-Revonut · 03.16.2009, 01:02 AM

Well everyone thinks Lipos are dangerous....I've heard horror stories about Nimh too. Nothing seems to happen fast with lipos, they don't just explede, they swell for several minutes first. Because NiMh are in a metal cylinder the preasure builds till they explode. A guy I race with told me that one of his 4cell packs shot across his basement and was on a shelf 6' off the ground after a cell exploded while charging.

If your pack will even accept a charge it could blow that cell and the pack could become a projectile! What kind of cells? If they are decent make a 4 cell pack and throw it on ebay, a carpet racer may want it for a practice pack

rawfuls · 03.16.2009, 01:20 AM

They're a GREAT quality pack.
I love(d) them.
Cheapbatterypacks.com
Elite 5000mAh "Upgraded" with Solder Spots and not standard weldspots.

I have two packs, one of them is still in sexy shape, the other one is.. well we're talking about them

E-Revonut · 03.16.2009, 01:21 AM

You can order single cells from them, take the bad one out and replace it

rawfuls · 03.16.2009, 01:22 AM

I've never been a big fan of spot soldering packs, in fact I'm scared of doing such... =/

Oh liiincccc :D

kulangflow · 03.16.2009, 10:45 AM

I had a NiMH cell explode once. It sounded just like a gunshot in my ear. Scared the crap out of me.

Don't be scared of soldering! Just practice on that crappy cell 'til you're good at it.

ClodMaxx · 03.16.2009, 10:51 AM

Quote:

Originally Posted by kulangflow

Don't be scared of soldering! Just practice on that crappy cell 'til you're good at it.

...and be sure to discharge the cell first.

kulangflow · 03.16.2009, 11:25 AM

Quote:

Originally Posted by ClodMaxx

...and be sure to discharge the cell first.

Yeah, good call!

rawfuls · 03.16.2009, 06:44 PM

Aren't NiMH's just like lipos when soldering?
That you'll need to get the same life of the cell?
Say if you put a new cell onto an old pack, wouldn't it screw up the stuff?

I dunno, I'm lost.

ClodMaxx · 03.16.2009, 07:36 PM

ni-mh isn't nearly as sensitive. it's only a concern if you're racing. the newest cell just won't deplete as much as the others, and also not charge as deep as it's capacity.

rawfuls · 03.16.2009, 07:43 PM

Ah, gotcha.

Will I need to replace the bar as well?

Of do I can I just unsolder and resolder.
I'm still.. scared.