Ultimutt

Hello,

I am brand new to electric R/C so a fellow flying club member who supposedly "knows all about electrics" and I were soldering Dean's micro connectors onto *my* new Apogee 830 3 cell lipos and he was using a alligator clip stand to hold the connectors while he was soldering. The Deans micros require that you connect the plugs together before soldering to keep them from being damaged. I had done the same a few minutes before but I had plugged the pack into the connector on my charger, and he had just plugged an unused connector into his while he soldered, which he apparently does all the time (seems like that's not a very good way to do it!). In any case he must have moved the connector enough with the soldering iron to cause the connector to pop out of the clamps, I looked over and saw a small and very brief spark as the connector brushed up against the stand for an instant as it fell. I then saw the connector he had plugged in with the two pins exposed and wasn't all that surpised what happened. I am new to Lipoly but have read a bit about them and took the battery to the battery bunker. I noticed nothing wrong, no heat, smell, swelling, or anything. . . but I am worried about the pack and wondering what I should do with it. He didn't seem to think it was too big of a deal since the short was for such a brief duration, and the pack wasn't warm. . . but maybe he just felt guilty. In any case I am pretty bothered with the situation and am not sure if I should use the pack, or if there is a way to know if it's a problem or not.

Thanks,

Bryce

AgCat1982

I would use it and keep a close eye on it the first few times. If it charges with no problem I would try it. Just my opinion.

Glacier Girl

My Feedback: (4)

Ulitmut,
I would agree with Agcatsbest, Also I would think it wise to find someone else to do your soldering. You apparently have a little more common sense then the "knows all".
BJ

Espen K

I have shorted one pack some months ago and I still use this battery without any trouble. But as mentioned above you have to look carefully during the first charging.

Trogdor the Burninator

I momentarily shorted a new lipo that I was soldering connectors on once. It was for a very short time so, even though I saw a little spark, the pack never got hot or anything. I've used it all last season and really abused it and its fine to this day.

I've always plugged in an unused connector and not really thought about shorting on the alligator clips. Maybe I'll just wrap some electrical tape around the exposed contacts next time... but probably not!

Matt Kirsch

My Feedback: (21)

A momentary short GENERALLY does not cause any damage. However, all due diligence should still be taken to make sure the pack is not in a dangerous state.

8KCABrett

My Feedback: (1)

My Apogee 830's have the new "Voltage port" which can be used to evaluate the state of each cell in the pack. I don't know how to do that, but it seems like this could be of use to you in that situation if your packs have this connector installed.

I haven't seen a cahrger/cycler that can be plugged into the port, but perhaps that is on the way from Apogee.

BadSplice

My Feedback: (1)

I'm kinda new to the whole lithium thing too.... Ive never heard that you had to have the deans plugs connected to solder... Ive soldered on several deans connectors, but never plug in an unused plug to the one Im soldering on. Ive never had a problem, have I just been lucky?

8KCABrett

My Feedback: (1)

Well, I used the Dean's Micros also, and they do say that you should plug them into another one when soldering to help dissipate the heat. . . this seems to only be with the micros, so if you were using the larger connectors (ultras etc) it isn't in the instructions to connect them.

Trogdor the Burninator

connecting deans ultra before soldering really keeps the pins in alignment and makes them much easier to separate later. There's a noticeable difference between the connectors I soldered by themselves and those with the other plug connected.

BadSplice

My Feedback: (1)

good to know, I'll try it on the next one I do...... it does occour that all of my plugs are hard to plug and unplug, I just thought that was how it was supposed to be.....

Ultimutt

Thanks for the advice, I had feared the worst and ahd a hard time figuring out what I could do to know if it was ok or not, and if not what would happen. I will keep an eye on it, and keep my fingers crossed!

Thanks,

Bryce

Ultimutt

Well,

The pack was fine afterall, but now something worse has happenned!!! I was in a hurry, the wife was asking me to clean the kitty litter and and I wanted to swap the battery that was done charging for a drained one. . .I unplugged one, and then plugged the other into the charger. . or so I thought. . .I had actually plugged the two packs together, I unplugged them, but they were warm. The Deans Micros dont have any protection against such things, the red plugged into the black, the black into the red.

Is this $82.00 down the drain???

I think I am just about done with electrics.



-Bryce

Ultimutt

I picked up a voltmeter and measured the voltages in each cell of each pack, here is what I found:

Pack #1 (the charged one)

Cell #1: 4.14 volts
Cell #2: 4.14/4.15 volts
Cell #3: 4.14 volts

Voltage as read off the Dean's plug (total pack voltage): 12.43 Volts


Pack #2 (uncharged/or partially charged)

Cell #1: 3.62
Cell #2: 3.62
Cell #3: 3.62

Voltage as read off the Dean's plug (total pack voltage): 10.86 Volts

So the cells seem to be in the right ranges for their respective charge states, and they are each more or less identical so that seems like good news. . .

Trogdor the Burninator

You might have gotten lucky because the time was really short but I'd watch that pack during use and charging very closely for awhile just in case.

If you want to change, Deans Ultra plugs can't be reversed like that.

Ultimutt

Today I checked the packs again to see if they changed overnight.

Pack 1 had all values the same as yesterday, Pack 2 measured a slight increase since yesterday of .01 v per cell up to 3.63 v/cell.

I charged Pack 2, the battery that had the partial charge, and watched it carefully for any signs of anything unusual. All seemed OK but it was a tense hour with the pack in the backyard in the firesafe, at the end of the charge I checked the cell voltages and found the following:


Cell 1: 4.17
Cell 2: 4.17
Cell 3: 4.17

Apogee lists 4.2 Volts as the maximal permitted voltage, so this looks like a good charged voltage.


After waiting about two hours I checked the pack again to see how much charge it held, all cells now read 4.16 V so there was a drop in two hours of .01 volts per cell.


I haven't plugged them into the ESC and motor just yet, but I guess that's the next step?