dereckbc

I use to be a fan or Thunder Power LiPo batteries, but no more after my last two orders. Use to be their C Rating was close. I decided to upgrade batteries from 3S to 4S for my EF 540 Edge, so I ordered 4 of TP ProLiteX model TP2200-4SPX25 a 4S 2200 mah 25C battery.

Once received I run them through my usual 3 cycle charge discharge cycles at 1C, then I take them to Storage Voltage at room temp and measure Internal Resistance to determine the true C-Rate. All 4 of them fail significantly. The best battery measures at 14 milli-ohms and on a 2200 MAH pack calculates to 14C and the worse pack measure 19 milli-ohms or a 11C. Absolutely horrible.

Going to stick with Gens Ace and my favorite Glacier. Sorry TP but you are fired.

mclarkson

Ouch. Did you contact them about it?

firemanbill

TP still makes batteries??? lol

They have been second rate for years. Of all the brands I have bought they have consistently been the worst.

birdDog

1/2 the quality. Twice the price.TP

Turbojoe

A few years back when Thunder Power started these stupid sales where you had to wait weeks to have the packs you ordered "built" for you a bunch of us on RC Groups (once we FINALLY got our packs) did tests using the Wayne Giles ESR meter. Of all the TP packs I bought up to 70C not a single pack tested higher than 23C!! And that was after cycling and testing under the same conditions each and every pack. I still have 2 3S 2200mah TP packs NIP that have never been pulled out of the bags. To date I don't think I've used a single pack I bought during that sale. Couldn't be more disgusted with myself for wasting the money with a company I used to trust.

TP used to be the best of the best 15 years ago. Now it seems all they are doing is ordering reject packs from China and slapping their label on them. The ONLY packs in my possession that test close to their rated "C" so far have been Glacier and Gens Ace. In fact Glaciers sometimes exceeded their rating by 1 or 2 "C" on rare occasion.

I'm with dereckbc. Thunder Power will never sell me another battery.

Joe

birdDog

Haha. Intrigued by the Giles ESR meter, i just wen to ProgressiveRC to check one out. Clicked into the clearance section and all paraboards wired for Thunder Puffer, I mean Power, are around 1/2 off.

dereckbc

+1. Gens Ace is decent and Glacier in my experience is excellent but seen short lived and puff up a bit early.

To my surprise I bought some Turnigy Nano 3S 2200 mah 25C packs about 2 years ago, they met my expectations. When I first bought them, the highest Ri cell was around 3 milli-ohms, and no no higher than 4 which is still very strong. Cannot beat it for the price.

dereckbc

UPDATE:

Thought I would update this post. Since writing it, I got my money back from TP. Also got a nice bonus this year so had some cash to spare. About 2 years ago I bought a few 3S 2200 mah Turnigy Nano Tech cells along with Gens Ace. To my surprise the Turnigy out perform and outlast Gens Ace and Glazier I bought at the same time. I know this for fact because I log all my batteries capacity, Ri, and condition. All the Turnigy Nano Tech cells I purchased two years ago still fall within spec and absolutely no Puffing. None of the Gens Ace or Glazier still fal within spec and they al have the same amount of flights. Still good enough to use, bu tnot as good as the Turnigy Nano's to my surprise.

I will be the first too admit I dislike Chi-Com junk and knock-offs. Turnigy has a bad reputation and I have never seen a Zippy not puffed up after a few runs. So with my extra cash I bout 4 X 4S 2200 MAH 25C cells and ran them through 5 cycles on the charger. I had a wonderful surprise. Everyone one of them exceeds or meets spec.

Capacity among the 4 are 2285 to 2380 measured at 1C Rate. Be advised Lithium Polymer cells we use are measured at 1C. discharge slower and they will test higher, and if discharge faster will be lower. That is Peukert Law in play.

My big pleasant surprise, just like the older Turnigy Nano Tech, Ri indicates the C-Rate, 25C is true. When measured at 50%, SOC at room temperature, and rested for 1 hour, all cells range from 2.1 to 4.1 milli-ohms. FWIW a 2200 mah 25C battery, no single cell should be higher than 4.03 milli-ohms. 4.1 is the highest and close enough to be a true 25C battery. Turnigy of all cells I have tested come that close to True C-Rate.

This keeps up and I may have to move Turnigy Nano Tech to the top of my list. Looking at some other log files I have seen indicate similar results.

Stay tuned.

birdDog

I have been a big fan of Turnigy brand LiPos for a few years. They hold up well.

A couple of 45C Glaciers that I bought one season earlier and rode hard, outperform fresh 75C packs. It's really turning into hit or miss these days.

Citabria32Yankee

Yep. $8.95 for ”1” 160mah 1S 3.7V. Lectron Pro: $7.99 for “2”.

dereckbc

Mixed feelings for me so far. In my experience I have nothing nice to say about Turnigy Zippy and lower end batteries. I never ever seen one test to spec, or not puff up after a few uses.

However Turnigy Nano Tech with my limited 2-year experience with them is winning out over Gens Ace and Glazier. The Turnigy's Nano test out better initially and hold up longer in my experience. For the price cannot be beat as both Gens Ace and Glazier are more expensive. That is starting to win me over.

Now what really frost my pumpkin with all the battery manufactures is C-Rate claims. All of them are a bunch of damn liars, and cheating customers period. That statement requires an explanation. statement.

Not only do I test and log all my batteries, I have tested hundreds of them out in the field from my peers. Some of those high C-Rate batteries demand a huge price. Go price out 35 to 75C batteries up against say 25C. I have never ever seen a single battery test greater than 30C. Even on new so-called 50/100C batteries that cost 2 times as much as their 25C brother. In fact I think I can say without a doubt it would be impossible to make a battery greater than 30C if a STANDARD were used.

When I was on IEEE Battery Committee, we tried to come up with a Test Standard. None could be agreed upon with the lithium battery manufacturers. On the flip side any other battery chemistry is easy because it is based on a percentage of voltage drop of 3% which is a great way to equal the playing field as that allows the user 2% voltage drop on wiring to total Voltage Sag is 5% from battery terminals to load device. Lithium battery manufactures want nothing to do with a standard. They make it up, and charge big bucks on the unknowing public.

Well just so happens if you work the math, 25C works out to around 8% voltage sag on any lithium battery. That would be an 8% power and heat loss. One member here and on RCG pointed it out to me last year. Cannot remember his name but he makes a meter to measure Internal Resistance. Gile's maybe?

Anyway there is a formula Giles or whoever came up with seems reasonable based of 6 watts per Amp Hour of cell. With that I will demonstrate that it is almost impossible to get anything greater than 30C. I will use an example of say a common AH rating of 2200 mah or really is 2.2 AH. FWIW using mah is just a marketing gimmick to make a small battery sound larger than it is. To determine a common Thermal C-Rate, one must assign an amount of power that can safely be dissipated upon a thermal mass. AH and physical size are directly related to each other. So the first step is to find out how many watts a cell can tolerate based on the AH size. The rate is 6 watts/ AH. So for a 2.2 AH cell we have 2.2 x 6 watts = 12.2 watts per cell. Next step is to physically measure the cells internal resistance and call it RI. From there it is simple Ohm' Law; Current = square root of Power / Ri.

So we measure all the cells and find the highest cell to be .004 ohms aka 4 milli-ohms. Square root of 12.2 / .004 = 55.2 Amps. Then to find C-Rate = Max Amps / AH. So 55 amps / 2.2 = 25C. To get to 35C on a 2200 mah battery requires the resistance to be .002 milli-ohms. Lowest I have ever seen on a 2200 mah cell is 3 milli-ohms or 29C, and that was on a new battery rated 45C.

Personally I think 6 watts / AH is way to much heat, but I could live with it if that was the Standard to be measured by. I have asked many battery manufactures how they determine C-Rate. None have replied.If I were the battery Czar would be based on 10% voltage sag and in that case no greater than 20C rate could be made.

Citabria32Yankee

My TP 103CQ Charger gave up the ghost this morning. Goodbye TP, Hello Venom Power.