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-   -   Lipo Battery got fat ? (https://www.rctech.net/forum/radio-electronics/409451-lipo-battery-got-fat.html)

guss2009 06-19-2010 08:04 AM

Lipo Battery got fat ?
 
I bought a lipo battery for my Blue ofna starter box. I put dean plugs on the battery since the box had dean plugs on it already. When i plug the lipo battery to the starter box it had charge but it got a little hot. My boy told me lets use it like that on the box since it has charge. We went to the track and the battery was working but then it die on us. When i looked at the battery it was FAT and hot. Why did that happend, was i supposed to charge it first or does my starter box needs a regulator? also after i let the battery cool down i put it to charge and i checked the cell and they were on 2.8. But then it started to pick up charge and it charged the lipo battery completely. It still show alittle fat on it. but it worked.

This the lipo battery i got for the starter box.

http://www.hobbypartz.com/83p-2200mah-4s1p-148-20c.html

guss2009 06-19-2010 08:13 AM

Update... I just checked the lipo Battery and its back to normal, No swell on it.

shultz 06-19-2010 09:30 AM

PLEASE do some research/ reading on lipo safety and use... tons of info out there on the net.

As for what happened... you drew WAY to many amps out of the pack...that is why it got hot and swelled... probably discharged it to low as well. The pack IS damaged... it may still work but make no mistake it is damaged.

Lipo's are great when used properly... treat them wrong and BAD...BAD stuff WILL happen... for instance... you could burn your house down kinda BAD:eek:

guss2009 06-19-2010 09:41 AM


Originally Posted by shultz (Post 7562134)
PLEASE do some research/ reading on lipo safety and use... tons of info out there on the net.

As for what happened... you drew WAY to many amps out of the pack...that is why it got hot and swelled... probably discharged it to low as well. The pack IS damaged... it may still work but make no mistake it is damaged.

Lipo's are great when used properly... treat them wrong and BAD...BAD stuff WILL happen... for instance... you could burn your house down kinda BAD:eek:


NO worries... I know about the damage the lipos can make. I have a lipo bag to charge it and im always checking it. I just wanna know what happend to the lipo that it got Fat and hot. It also when back to normal.

shultz 06-19-2010 09:53 AM

you have an Amp meter? if so hook it up to your start box using your old batteries or some power source other than the lipo... now start you're buggie and see how many amps you draw... I'll bet it's WAY over the 44a max continous that 2200Mah lipos can produce:nod:

you simply need a bigger battery... how big will depened on the MAX load the starter box can demand.


Edit:

I did a little looking around and it seems that battery SHOULD be plenty...I figured a start box pulled ALOT more amps.

Check see if your start box motors are worn and check for any binding... I know your pulling to many amps from your battery... not sure why though.

Duster_360 06-19-2010 10:51 AM

Lipos are delievered partially charged - they are not fully charged so when you went and used it that way, you overdischarged it and the styarter box motors were pulling more amps than the partly charged lipo could supply and the lipo got hot and puffed. That size is common - it just needed to start fully charged not at 50% or less....

I'll agree that you've damaged it. Its a good sign it came back to normal size, but damaging it you have prob reduced its capacity (mah) and reduced its life (number of charge/discharge cycles). Lipo should be protected in some way from overdischarging - using them in cars and trucks the speed copntrol usually has a low voltage cutoff that prevents overdischarge. You have nothing in the starter box to prevent overdischarging. You either need to check it with a DVM/MM as you use it during the day to make sure its still over 12v (3v/cell is minimum voltage, shouldn't go below that) or buy a low voltage alarm (eBay) that plugs into the balkance wire that will alert you when the voltage starts to get low. You do have a lipo balancing charger to charge it with?

It wouldn't hurt to do a little reading on lipo - you could have easily caused a fire to start in the box by the way you were treating the lipo. This is not a gell cell where you use it until its flat.

http://www.rchelicopterfun.com/rc-lipo-batteries.html

guss2009 06-19-2010 11:04 AM


Originally Posted by Duster_360 (Post 7562343)
Lipos are delievered partially charged - they are not fully charged so when you went and used it that way, you overdischarged it and the styarter box motors were pulling more amps than the partly charged lipo could supply and the lipo got hot and puffed. That size is common - it just needed to start fully charged not at 50% or less....

I'll agree that you've damaged it. Its a good sign it came back to normal size, but damaging it you have prob reduced its capacity (mah) and reduced its life (number of charge/discharge cycles). Lipo should be protected in some way from overdischarging - using them in cars and trucks the speed copntrol usually has a low voltage cutoff that prevents overdischarge. You have nothing in the starter box to prevent overdischarging. You either need to check it with a DVM/MM as you use it during the day to make sure its still over 12v (3v/cell is minimum voltage, shouldn't go below that) or buy a low voltage alarm (eBay) that plugs into the balkance wire that will alert you when the voltage starts to get low. You do have a lipo balancing charger to charge it with?

It wouldn't hurt to do a little reading on lipo - you could have easily caused a fire to start in the box by the way you were treating the lipo. This is not a gell cell where you use it until its flat.

http://www.rchelicopterfun.com/rc-lipo-batteries.html


Yea thats what i though i did... overdischarged it using it without been charged. I checked ebay for the low voltage alarm and found one... Is this one good? Im using a Triton Eq charger.

http://cgi.ebay.com/Maxpro-4S-Lipo-B...item335d15b4eb

Duster_360 06-19-2010 11:13 AM

That'd be just what you need.....

Triton will get it done. Charger will reduce charge current to stay below its power limit, but it'll do a good job otherwise. You will need to pay attention to the balance between cells in that lipo, cell imbalance tends to be aggravitated with deeper and deeper discharge.

guss2009 06-23-2010 02:53 PM

5 Attachment(s)
Alright i just received the lipo battery monitor. But the connector doesnt have the wires connected and it has 5 slot, which slot do i solder the negative wire and the positive wire? I believe they go on each end of the connector. Also the connector has a flat side and the other side has 2 openning. What side the wires connect? I have the 4s monitor.

Attachment 608406 Attachment 608407 Attachment 608408 Attachment 608409 Attachment 608410

Duster_360 06-23-2010 07:17 PM

Your link to the 4S isn't working, but it should have a jst-xh type balance connector and on one side there should be a red wire and on the other there should be a black wire. These are pack pos and neg - using a DVM/MM you will read full pac voltage across those two leads. These should be the pos and neg you use for the alarm

In this balance scheme, there are 5 wires (1 + number of cells) so there should be a 5 wire balance connector on the lipo. It is keyed to properly align pos and neg - just align the key tabs and solder the red and black into the alarm connector such that both the red and black 'continue' across the connector.

If the wires are not correctly color coded, you'll have to use a DVM/MM to figure out which side of the balance connector is pos and neg.

guss2009 06-23-2010 07:33 PM

Got it. I was wondering why there's 5 slot on the connector and only 2 cables on the monitor. But i line it up with the lipo balancer connector and i saw what side the pos & neg wire slot i have to solder it to. I solder the cables, then connected the monitor to the lipo and it beeps once and then a blue light stay lid. i just gotta figure out how this light thig works now. Thanks for all your help. Duster_360 i appreciated.

Xmod_Racer 06-23-2010 07:57 PM

yeah those monitors stay blue for above 3.6 volts/cell i think. Then it ranges. If its blue and beeps every once and awhile it getting low. Solid red and no blinking means pull off the track. When its red and blinking you better pull off because your lipo is about to get damaged.

Duster_360 06-24-2010 03:23 AM


Originally Posted by guss2009 (Post 7582375)
Got it. I was wondering why there's 5 slot on the connector and only 2 cables on the monitor. But i line it up with the lipo balancer connector and i saw what side the pos & neg wire slot i have to solder it to. I solder the cables, then connected the monitor to the lipo and it beeps once and then a blue light stay lid. i just gotta figure out how this light thig works now. Thanks for all your help. Duster_360 i appreciated.



Simple - the monitor is only checking total voltage - only two wires are needed to monitor total pack voltage., This alsrm is not monitoring individual cell voltages - that would be the only reason you would need all 5 wires. Go back to the website in your link - theer is an 'owners manual' where this is explained. Take sec and read the manual - its prettty short.


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