I think my battery swelled...and I don't know why.

[Whirly-Girl]

Help:

My hubby is deployed and I "thought" I was doing everything right to charge and use my Thunder Power Li-Po for my T-Rex. I have 2 batteries, one 1320mAh that I only use for test and setup cuz it doesn't have enough oomph to fly the T-Rex. The other battery is a TP 2100mAh. I got home from a fun fly last weekend and put all my li-po's on charge one at a time on my Duralite 3+1 charger. My husband even made it pretty dummy-proof and labeled the wires 11.1V and I know to plug them into the TX plug. Every battery charged fine except my 2100 pack. It appears to be bulging on both sides. I plugged it into my heli and advanced the throttle and it turns the motor then cuts out. This charger didn't damage any other battery and it has charged this 2100 pack a few times before - it is still a relatively new pack...flown maybe 5 whole flights.

Can you guys give me some ideas as to what I missed or messed up? Could this be a defective battery? Does Thunder Power check batteries and replace them if they find they are defective. And, most importantly, I know charging these things can get dangerous, but does storing a swollen li-po pose any fire hazards to my household?

[Shortman]

Hi Whirly Girl, there are many reasons for a Lithium Polymer pack to swell, 99% of the cases are from improper charging or bad cell (leading to a destroyed pack). If you could tell me a little more information on how you charged the Thunderpower 2100mah, what the charge rate was? Hopefully not exceeding 1C or 2.1Amps.

However, a swollen pack is not uncommon for Li Polys. It does pose a fire hazard to your house, keep it outside away from any flammable object! I mean it! Second, contact Thunderpower batteries and ask for Charlie Wang. He is the owner of Thunderpower and will replace your pack free of charge.

Hope this helps and let me know when you get a new pack or if you find anything else out. :D

[Whirly-Girl]

Well, the last 2 charges are this pack were on separate chargers. The 3rd and 2nd to last charges were both on my Triton charger hooked up to my car at a heli fun fly last weekend. Battery took the charge fine and flew fine. I charged it at 11.1V and 2.1Amps. It took approximately 67 minutes to charge. When I got home, I plugged it into my Duralite 3+1 charger in the 11.1V charging jack. This charger is just plugged into the wall. From what I understand, this charger senses what condition the battery is in and charges it accordingly...I unplug it when the green light goes out.

Does this help?

[Shortman]

Yeah, I believe the Duralite Charger has a limit of 500mah anyways so you we can rule out charging it over 1c. I am also wondering however, if the duralite charger is for 4.1 or 4.2 v cells. Because before Li Ions were rated at 4.1 and now they are up to 4.2, this could potentially also cause problems. If you could check and see, this would confirm the other possibility of ruining the pack.

[rob_jones]

Draining a LiPoly below 3 volts per cell can also cause it swell up. If you discharged the pack to below 9 volts and/or got it really hot (over about 150 degrees), it can swell up.

LiPo's are great for the hobby, but they can be delicate and require special care and feeding.

You can return it to Thunder Power, but don't expect a free replacement. Most likely they'll offer you a new pack at 50% cost.

[FlyinTiger]

Hi Whirly Girl, there are many reasons for a Lithium Polymer pack to swell, 99% of the cases are from improper charging or bad cell (leading to a destroyed pack). However, a swollen pack is not uncommon for Li Polys. Second, contact Thunderpower batteries and ask for Charlie Wang. He is the owner of Thunderpower and will replace your pack free of charge. :D

Well, Whirly-Girl, I called Duralite and they confirmed what I remembered reading and just read on their "specifications" for the 3+1 Duralite Charger:

"The 11.1V charging jack is designed to charge a 3 cell, 3.7 volt per cell, Lithium battery, either Ion or Polymer." The Duralite Transmitter batteries are 3 cell, 11.1V batteries. It also charges at a rate of 400mah, not 500mah, so no worries in charging it too fast. It would take 5.25 hours to charge.

They told me you have a bad cell in your pack and that you should be able to get it replaced by the manufacturer. I guess once in a while a bad pack gets out of the factory...even with a quality company like Thunder Power.

Hopefully Mr. Wang will replace the battery. In the mean time, go ahead and continue charging the 3 cell foamy 11.1V Li-Poly batteries with the Duralite charger if you want, until I get home and make a mini-Deans charging lead.

[Shortman]

In that case, as long as the pack wasn't abused, Charlie should replace the pack free of charge. I gave her his contact, just let me know if he takes care of you.

[Whirly-Girl]

Here is my reply from Mr. Wang in case anyone else needs this contact information for themselves:

"Please call customer service at (702)228-8883
I have full time job in R & D and other businesses.
Regards,
Charlie"

I will try calling Wednesday morning and I will post my results as soon as I get them. Meanwhile, HeliProz has a box full of goodies coming my way on Thursday...including a 2nd TP2100 pack for now. :D

[Shortman]

Yeah thats the customer service over at Thunderpower, just describe your problem and let them know you have a bad cell. All should be taken care of.

[Whirly-Girl]

In case someone else needs this contact information in the future, send a letter with your name and address and description of the problem to:

Thunder Power Batteries
4720 W. University Ave
Las Vegas, NV 89103

My battery has just been sent in and I will post the result as soon as I hear from them.

[rob_jones]

Cool. Thanks for the update and info! :glasses2:

[Shortman]

Yep, I'm sure Charlie will have you taken care of. I wish Jason still worked there but he went over to Horizon and is working in their electric flying department with Thunderpower now. He use to be the head tech/customer service guy there and would always help you out.

[WillJames]

I know MANY people who think TP customer service took a %*@!%&*)!! since Jason left. Enough to scare me.

[madgadget]

The jury is still out for me but the time seems unreasonable.

[Whirly-Girl]

The jury is still out for me but the time seems unreasonable.

I called TP again today...after four months they finally found my battery and "are going to send a new one out right away."

We'll see when it gets here...