DTB

My Feedback: (15)

I have a ThunderPower 1320 3-cell pack (decent battery) and a Kokam 1500 3-cell pack (hate it) that need to be replaced and want to buy a balancer also. I get roughly 50% capacity now from the ThunderPower and 30% capacity on the KoKam. The Kokam was given to me, which I admit never gave out a lot of power compared to the ThunderPower. I've had the ThunderPower for about 1year. Don't know how many cycles have been put on it, but I'm sure the cells are unbalanced because at the end of a flight, one cell is slightly puffed which I DON'T LIKE at all. I noticed the puffing today after a flight, but the other two cells are normal. I like the ThunderPower, but wonder if any new better packs have come out lately. I've heard about a new Li-poly that charges in 3-minutes and has a 30C discharge. Any truth to this?

What brand of Li-polys do you like the best? If a balancer is used, which one also?

Thanks,
Derrick

redgiki

Just so you know, batteries are considered "bad" when they only reach 80% of rated capacity.

Yeah, the cell is toast, and you're almost certainly overcharging the remaining cells. Cut it out, balance the remaining two cells, and make it a 2S pack. I'm sure you can figure out something to fly with it

If you continue to fly it, you have probably less than 4 flights left after the first puff, and those will seem awfully short. I've puffed three packs (dirt-cheap ones, to be sure...)

The general rule for LiPo batteries is "newer is better". If you look at the timelines, every new flying season has brought dramatic improvements in Lithium technology since 2002. It continues today.

The principal difference between Thunder Powers and Kokams now is that TPs deliver a bit higher discharge, while Kokams keep their temperature a bit lower. This is, of course, if I read my info correctly Kokams seem to last a fair bit longer. But once again, "newer is better", so do you need 450 flights when 200 will do before you're ready for new batteries anyway?

Experimental lab-tech stuff that's probably at least a year away from manufacturing for aircraft.

I'm shopping around for my next supplier. I've mostly bought generic packs from RC-Dymond.com, and also some GWS packs. The Dymond packs are just too spotty on the quality control. 3 of 5 have been great, always perfectly in balance, and no issues. 2 of them were way out of balance and bloated a cell quickly, thus becoming 2S packs. The GWS ones were crap for discharge from the get-go, and died within a few dozen flights. One of my Dymonds has 200+ flights on it, and is still running at some 90% of rated capacity.

I think for small stuff, I'm going to go with Thunder Power or CommonSenseRc.com. I use a TP-205 balancer, so the Thunder Power LiPos have that appeal. I have a .40 and .60 conversion waiting in the wings, and for that I need a much higher-amperage charging system than I'm currently using. The FMA Direct Balance Pro HD (formerly Skyvolt) seems to fit that bill, so a pair of $400 battery setups may be on my Christmas list

--
Redgiki
- - - -
Thought for the moment:
paak, n: A stadium or inclosed playing field. To put or leave (a
a vehicle) for a time in a certain location.
patato, n: The starchy, edible tuber of a widely cultivated plant.
Septemba, n: The 9th month of the year.
shua, n: Having no doubt; certain.
sista, n: A female having the same mother and father as the speaker.
tamato, n: A fleshy, smooth-skinned reddish fruit eaten in salads
or as a vegetable.
troopa, n: A state policeman.
Wista, n: A city in central Masschewsetts.
yaad, n: A tract of ground adjacent to a building.
-- Massachewsetts Unabridged Dictionary

DTB

My Feedback: (15)

That is some great information you have given me. I actually never thought about making it a 2S pack. I'm sure I could find something to do with it even if it is just to fly around and not 3D (less power). I am really looking at the TP-205 myself. Does it come with everything that is needed or is there other items needed to make it work also?

Thanks

Iceman30

My Feedback: (14)

This is where I get my batteries...I fly about 4 packs every day..depending on the wind...I did get the balancer, and if you get it with the batteries, call them and they will take 10$ off the balancer, making it 20 bucks or take 10 off the balancing charger, but if you have a charger, you only need the balancer....I have 4 of their 12C discharge packs...THEY HAVE THE POWER OF THUNDER POWER...no puffed cells even after a year...20$ less than thunder power..

http://www.xushobby.com/servlet/Cate...12C+Continuous

DTB

My Feedback: (15)

Thanks for the info, but I bought another 1320mA 11.1V TP already with a TP-205 balancer, but only paid $10 more for the TP pack compared to the 1300mA 11.1V listed on the link. I do like their prices and may try one of their packs also since you have had not bad luck with them and still happy with the performance.

What setup are you using the pack on? Average Amp draw from your system?

Iceman30

My Feedback: (14)

i'm running them on a yak 54 from rcxplanes..about 18 oz with hacker a20-22 motor..with 11-4.7 prop...i have never checked the amp draw..but I do have some older 1200 etec's that only have discharge rate of 8C max and they provide about little over 1/2 the power of the 13C packs...so she must be drawing some power...I am going to pick up a watt meter soon, but I have 2 foamies, both the same setup so never really could find the need for one

oh, the packs after about a year have become unbalanced and the balancer should be here this week, so I can let you know if that improves the performace...right now my charger is only able to put about 700 of 1300 mah back in the pack..have a triton charger...was 1300 or 1100, or so depending on how long i flew..used to get 12 plus minutes of 3d flight..now about 5 min..but used my dc meter to check the pack and cells are way out of wack..

have you had any experience using a balancer after the voltages got off to get the pack back to spec..now keep in mind I DO...fly everyday...if the wind allows...just flew out 2 packs 1/2 hr. ago...so have atleast 100 or more flights on each of my batteries...

DTB

My Feedback: (15)

Iceman, I have a Himaxx 2812-0850 I'm using with the TP 1320 3S and your situation sounds exactly like my situation. I was only getting in about 800 mA on a 1320mA pack and the flight time had been seriously affected as yours have. I just didn't have the power that I once did. I have lost count of how many flights I have and never balanced my pack also. The pack is about 15 months old now. I have packs that was bought prior to taps ever being placed on the pack to give an idea of the age of the pack.

I used my multimeter and found one cell dropping down to as low as 1.7V during a loaded test. I never had any problem with the pack until one day I noticed a cell that puffed a little during a flight which bothered me as I knew that was never a good thing. I check the pack again on the bench and sure enough one cell was way out of balance, but the other two were still in balance even under a load.

I removed the bad cell and made the pack into a 2S pack and ofcourse now I don't have the power out of the plane, but the flight time has returned and I am putting in 1100mA into the pack. It still flys, but hovering is not an option now with the 2S pack and had almost gotten to that point when it was a 3S pack due to the imbalance.

I have a Kokam 1500 non-tabbed pack also that did not give power even after a full charge. I checked that pack and sure enough, there was a bad cell in it also. I removed it to make a 2S pack also and now I have power again and putting in 1400mA into the pack again, but with reduced power.

I do have a new Thunderpower 1320 3S ProLite (tabbed) and a TP-205 balancer on their way. Since I will have a balancer now, I hope not to have a bad cell like that again as I was not able to check it easily after charging or before charging to balance the pack previously.

I tried balancing the bad cells manually back up the the correct voltage and it simply would not work. The damage had been done and would not stay in balance plus the bad cells were a danger in my eyes so I properly discharge the bad Lipos and discarded them so it wouldn't catch fire or do something to harm the trash collection workers.

With a balancer coming, I fell I would be able to catch any imbalance problem before it becomes a problem.

Iceman30

My Feedback: (14)

as far as throwing the old cells away...hopefully I can save my sets...I have 2 that have no balancing plugs at all but they are a lower 8c discharge pack and will not power a hacker outrunner for 3d...doesn't let enough juice out but did power my himaxx brushless geared set up great...thought about adding a balancing pin, if I could get a couple from xushobby but another thread on here sounds very complicated to do that...or it's too early and not sinking in...here is that thread

http://www.rcuniverse.com/forum/m_41...tm.htm#4158371

Oh, can you recycle the old cells at your hobby shop, instead of putting them in the trash...imagine nice little fire when smashed by a bull dozer [X(]

DTB

My Feedback: (15)

Adding tabs really aren't hard to do at all. I need to order some tabs for my 2s packs now.

My Lipo packs were no good and had started to puff. That is a big NO NO for using. I discharged the packs to 3.0v, then soaked them in saturated salt water for a day, then punctured a hole in the pack and soaked for another day. The packs won't be causing any fire now. They had .10v in them when I checked them before discarding them. That was the very reason I fully discharged the packs so no danger would be present even if smashed by a dozer. It would no just crush or tear apart, but no fire.

critterhunter

Check out Common Sense RC. They have some quality packs with a balancing plug already installed. This plug is recommended for use with the AstroFlight Blinky balancer ($25) and this balancer can be used with any charger before, during, or even after it's charged. The Blinky can also be used with other packs that have different balancing plugs on them such as Thunderpower. The Common Sense RC lipo packs are of good quality and feature air spacers between the cells to keep them cool. They also claim to use "real" battery raitings and not hyped up ones. The price is good as well. I picked up a 3 cell 10C 2000ma pack (20 amp with 30 amp burst ability) for $44. There are only a few companies that sell lipos any cheaper. I have two Dymond packs of the same above specs and paid $35 for them. However, they didn't come with a balancing plug but I've converted them over to use the molex style plug the Common Sense packs use to mate with Blinky.

DTB

My Feedback: (15)

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[X(] Guys I got my new TP-1320 3s Pro Lite pack today and WOW!!!!! [X(][X(]
Actually that is an under statment of my actual response when I tried them out for the first time, but we will keep it clean for the kids here. I tried it with an APC 10x4.7 on my new plane (will post that later) and it almost came out of my hand literally. I never cared for the APC 10x4.7 before with the old pack on my Himaxx 2812-0850, but I have never had that type of pull from my old TP-1320 3s pack even with a 11x4.7, 11x7, 12x3.8 or 12x6. The new battery is insanely powerful. Almost unreal.

I actually like the 10x4.7 the best so far and plus it isn't over stressing the motor, but still has great power. Longer flight times ahead now.