I've been using TP lipoly's for well over 2 years now. Never had any problems whatsoever. That is, until a couple weeks ago.

I had a pack that went bad and caught on fire. No warning signs, always have charged and discharged as usual. I always charge at .5C-.7C, discharged on this pack was less than 6c. All my packs are 3S so I never have to change the voltage settings.

The pack in question was a 3s2p 2100 and a 3s1p 2100 hooked up in parallel (3s3p). During a flight (30A static) I saw smoke coming out of the plane, landed immediately...

I took a huge risk by handling the pack and removing it from the plane and tossed it on the concrete ground where it proceeded to smoke for about 3 minutes and subsequently caught on fire.

The smoke seemed to come from the larger pack, but I didn't look closely long enough to tell. The fire caused the second pack to ignite.

I bought both of these at the same time as the store I bought from didn't have a 3s3p. It is about a year old but I know have less than 30 cycles on them.

Now here is the shocker. I sent it in to TP with a detailed letter of what happened, and they informed me that they will not warranty it because of misuse, not even an offer of 1/2 off on the purchase of a new pack... they considered it misuse because I ran them in parallel... this is news to me.

They told me they tell everyone not to run packs in series or parallel as it will void the warranty. I never heard such things nor have I found it posted anywhere including on their website.

You must use match pack(very close in IR) for series or parallel applications.

This is my only recommendation and that is how all TP packs are built.

I am not suprise about the accident because it is something that could happen

Regards,
Charlie (R & D, Thunder Power Batteries)

PS:
1)Only run pack in series if you fully understand the concept to use them correctly
2)Only run pack in parallel if the IR is close
No comment on charging.

For running them in parallel safely, is it sufficient to pair two TP packs of the same size with the same date code, or is it necessary to actually measure IR for several same-sized packs until a close match is found?

Thanks for commenting Charlie. My question and concern was that I was told "DO NOT RUN THEM IN PARALLEL" or else warranty will be voided. Is that so?

Originally Posted by gadzby

For running them in parallel safely, is it sufficient to pair two TP packs of the same size with the same date code, or is it necessary to actually measure IR for several same-sized packs until a close match is found?

Basically, every thing is relative,
The better match in IR, the less chance of failure,
The higher the discharge rate for unmatch pack, the greater the possible failure

Regards,
Charlie

Ok, thanks for that Charlie. I wasn't aware of the issue at all until this thread came into view.

I bet the smoke trail looked cool in the air though.

Originally Posted by fnnwizard

Thanks for commenting Charlie. My question and concern was that I was told "DO NOT RUN THEM IN PARALLEL" or else warranty will be voided. Is that so?

Warranty????? what Warranty???????

From the ThunderPower website:

Product Warranty

Product warranty is limited to original defects in material and workmanship. Warranty does not cover collateral damage. Due to the nature and use of this product there is no term warranty. Misuse, abuse, incorrect charging and other inappropriate use of this product are not covered under warranty.

Thunder Power Batteries 4720 West University Ave., Las Vegas, NV 89103 Phone: (702) 228-8883 Fax: (702) 228-8885 www.thunderpower-batteries.com

Why does everybody think that there is any WARRANTY on "fittness for use" on Lipo batteries for RC???????

Charlie, I'm not picking on ThunderPower as I have yet to find any company with a written term warranty on Lipo's.

Brad

Originally Posted by fnnwizard

Thanks for commenting Charlie. My question and concern was that I was told "DO NOT RUN THEM IN PARALLEL" or else warranty will be voided. Is that so?

I'd like to see the answer to this also. I noticed that Charlie's reply avoided the question.

Originally Posted by Charlie Wang

You must use match pack(very close in IR) for series or parallel applications.

This is my only recommendation and that is how all TP packs are built.

I am not suprise about the accident because it is something that could happen

Regards,
Charlie (R & D, Thunder Power Batteries)

PS:
1)Only run pack in series if you fully understand the concept to use them correctly
2)Only run pack in parallel if the IR is close
No comment on charging.

Charlie,
How do you Calculate/Measure the IR of your Thunder Power packs?

Thanks...
Gus...

Originally Posted by grouchy1

I bet the smoke trail looked cool in the air though.

Actually there was very little smoke at first. Barely noticeable, and power all seem normal.

After I took it out, it smoked continuously for about 3 minutes. It was smoking like a big smoke bomb... lots of smoke and very dense. Then it stopped smoking for 20-30 seconds... I thought it was done so I approach to get a better view... but then it started to hiss and it ignited.

Concerning the warranty, even though I have never had to use it, I have heard and read from fellow modelers that no other lipo company stands behind their Products like Thunder Power.

But when tech support told me not to run them in parallel it kinda shock me as I thought this was pretty common practice.

I just can't figure out why this pack did what it did. It was charged and discharged well within it's limits. Always in Parallel and was never ran hard at all so I just can't see how the IR would affect it that much.

NO WARRANTY:

Another example this time from Polyquest

Since many Radio-Controlled applications exceed the manufacturer's recommended maximum discharge rates there
is no warranty (expressed or implied) by the manufacturer, its Distributors and Retailers in respect to the
Cycle Life, Capacity, Cell Characteristics or Storage of cells/packs used in the Radio-Controlled market


Brad

Of course running packs in parrallel and series is common practice. How many 10s set ups are a single pack? Not many. Same thing with many 2p and 4p set ups. I'm suprised Charlie didn't step up and say something.

I've always heard TP customer service was decent as well. I have a couple packs to send in myself. Hopefully I am not in for a similar dissapointment.

Mike

MJWS, I was talking about running them in Parallel from individually bought packs, the packs you are talking about are they factory assembled packs that are IR matched?


I know many guys who run individual 3s2p and 2s2p in series to get CG balance better than a single 5s2p.

If this may cause major problems, it should be brought to light more.

FYI there is nothing in the ThunderPower

"Important Saftey Instructions and Warnings"

http://www.thunderpower-batteries.co...tyWarnings.pdf

concerning either series or parallel discharge of ThunderPower batteries..... There is a warning against "series" charging however.

In the end this has nothing to do with a WARRANTY and everything to do with good CUSTOMER SERVICE.

Brad