serious power

Hi Joe,
Yes you could have something there.
Something does change in the early cycles - maybe less so on high C cells.

You must also take manufacturer claims ,some anyway, with a grain of salt - re-branders are always the worst - the only thing that they might control is the adhesive on the sticky label.

There is a well known manufacturer that claims ' 9 out of 10 cats prefer theirs'.

Brian

wattsup

My Feedback: (1)

serious power, let me ask you a question or two, in a positive way, to hopefully encourage others to discuss their current experience with all the different brands of lipo batteries that we use in our 2m electric pattern planes. Which 5000 mah 5s packs have you found to provide the longest service and along with that the most optimal "C" rating that has proven to have add to that longevity? I full well understand there are alot of other variables such as particular power plant/esc combination, AUW of the pattern plane, individual flying style (big and fast), length of flight which may have a negative long term effect if discharged too much, etc. The bottom line for most of us will be the best available make of battery based on value (cost) and again anticipated length of service based also on others current use of a particular make. Thanks in advance, Everette

serious power

Hi Wattsup,
You are correct - there are many other variables - too many to allow an 'in context' response.
Also as I stated earlier ; I don't get through very many packs so I have a very small ,personal, data base.
For consistency 'in flight' and weigh to capacity reasons I like low C packs.
So far I have good results with TP and F3AU,, packs with the latter not having any packs fail 'early' due to one cell. I have had this happen once or twice with the former.
Right now I am testing some Zippy compacts - I must post on that thread,if I can find it.
These are just too cheap to ignore.

I'd like to keep this thread 'on topic' though as I think we need to grow a proper understanding of the subject.
Getting this one right may get us all some extra 'useful' cycles.

Brian

wattsup

My Feedback: (1)

Brian, thanks for your response. My experience base goes back 6 years and I have documented EVERY single flight with all the different makes of lipos I've used. Basically I've tried a total of 8 different brands of lipos with a capacity of from 4000mah to 5000mah and C ratings from 20 to 60 and the one thing I've found in common with all of them is a life expectancy range of 54-70 flights before they became unuseable. Note, these batteries have ranged in price from the most to the least expensive. BTW, I fly AMA Master's and have always flown a very conservative style. Like you, I feel this single thread could serve as a tremendous source of "lipo knowledge" if those who are interested in contributing were to keep this thread positive and only give "honest" responses and not use this thread as a tool to promote a particular lipo. As it stands now, most of us are out here floundering around on our own without a reliable source of knowledge based on real electric pattern experience to draw from. Hope this makes sense and others will come forward with the intent to help all the rest. Thanks again, Everette

serious power

Everette,
I would call that failing early.
I have one, one only, 3 year old TP 5000 prolite.
This was one of the first that they produced - it weighs 1144g.
The IR's are still 1.4 to 1.8.
It is a little squishy and a little puffed.
I do try to 'run them in' but without any real knowledge of what's what.
It must have between 250 and 300 flights.
I have others at between 100 and 200 cycles - now failed - but due to one cell only.
I have others at between 100 and 200 still going strong.

Storing them charged and over discharging are the two big no-no's.
It takes only one bad episode to hurt them badly.
I just don't know about running in.

Brian

wattsup

My Feedback: (1)

Brian, I've always "broken-in" each set of 10s packs with 5 flights at half throttle or less for 5 minutes and now I read that my method is disputed by an "expert" and is not necessary? Also note, I always fly on a timer set at 7 minutes which is plenty of time to fly the new AMA Master's routine. I never store my batteries charged and charge them either the night before or the mornng of the day I fly. By documentation I mentioned above, I keep track of the numbered set of batteries, time of each flight, post-flight voltage, mah's and IR's of each battery at the end of the charge cycle, post-flight motor temperature and most important the post-flight battery temperature. I've always felt one should keep records in order to get an idea of which batteries to purchase again in the future and for sure which ones to avoid if at all possible. Also, my planes generally have an AUW of 10 1/4 to 10 3/4 lbs. Believe me when I say, I'm trying to understand! Everette

wagen017

Hi Everette, I am like you, I record every flight, including details of charge, Ir etc. I also occasionally use my Eagle tree to see if anything out of the ordinary happens during flight. Typically I will read out my Jeti-99 to see voltage and Amps (low/high). I always have some problem to believe those that claim to have flown "thousands of flights" but keep no records.....

Anyway I prefer 25C type of batteries, also since they are the lightest.

Now I am flying with only one TP 4400 10C pack, which I normally charge with 20Amp, so almost 5C. So far so good, I only don't fly as much as I used to so have only done 120 flights sofar. Still all ok.

With 5C I charge about 12-15 minutes, which is quicker then I can recover from a flight. I found myself only using that one battery so in the end I gave away the ones I still had.

Volkert

wattsup

My Feedback: (1)

Hi Volkert, I appreciate your response. I've always been afraid to charge at any charge rate above 1C. But, it's obvious that you, like Brenner, are having phenomenal success charging at 5C. Years ago I started out with TP and along with the original set of packs, a TON of bad advice. I realize there have been a large number of changes in the "world of lipos" during the last 6 years since I converted from glow. Needless to say, you can't believe everything people say and let me add, very little ANY retailer advertises! It is unfortunate but, it is just another sign of the times. My plan now is to move up in capacity (5000-5800 mah) and down to 20-25C ratings and see how that goes. I had been running 4400mah/40C batteries with very little success (<60 flights). Even though TP is now coming out of China, perhaps they ALONE have the better mouse-trap or a least one that lives up to expectations! Thanks, Everette

serious power

Hi Everette,
The devil is in the detail on this one.
Before I get to that I should add that I have had one TP that failed earlier maybe around 60 flights and that was a single cell issue.
It was noticeable quite early on IR wise.
I did ,until this year, record all my flights.
Anyway back to the detail.
There are 3 or 4 of us that work together on this stuff - 5 to 6 years now.
At first we were using Pletty's and another well known battery brand , then anyway.
Those packs were no good and were easily hurt.
However we did learn what was going on pretty well.
Between us we had a variety of styles and different levels of discipline flight duration wise.
Some of what we learned;
If one loads the system to the max prop wise and or style/time wise the battery feels it. Battery capacity is an important factor here.
If one has high resistance in the system the battery feels it. This can come from just a single poor quality and or under spec,, connector ,multiples of the same , extra connectors (we only have two now) ,poor soldering,dirty connectors and long cables. Any unnecessary extra resistance is going to affect the pack.
We now shorten the leads as much as possible and use Emcotec 5.5mm or 6mm on the DC side and Emcotec 4mm on the motor side. This is relatively cheep to do and these good connectors last and last. Eliminate the spark if you get one. We even have a break in the charge leads that we connect last so as to avoid a spark to the pack connectors when connecting to the chargers.
The world is flooded with sub standard 4mm bullets.
50A rated connectors are not good enough on the DC side.
Lots of people are using 50A connectors and getting away with it - it seems. Define getting 'away' with it if you can - I can't.
A number of little things can add up to a lot. A number of slight over discharges can equal one substantial over discharge.
A few slightly high resistance points can add up.
Unnecessarily high prop load will hurt the packs ongoing - some people load their engine/motor to the max ??
The packs after a flight should read at 37V or above and should only have warmed up a little- 10 to 15 c above ambient.
Pack cooling is not very important provided they are not brought down too low voltage wise. They only heat when stressed at the end of a cycle.
Motor and ESC cooling is vital - again resistance - I think the rule of thumb is that resistance doubles for each 10 degree C rise.
Lower finishing pack voltage's or higher finishing pack temps means pain/stress for the pack. The duration or the Amp load or both are too high so.
The more under 37V and or the more over say a 15 degree temp rise the more the pack is hurt.
7 mins ,I assume take off to landing, is highish for a 4400.

Brian

wattsup

My Feedback: (1)

Brian, I suspect that most if not all may have an impact in everyone's experience. Perhaps a 4400 mah 40c 10s pack may not be enough for my needs or I'm expecting too much in an effort to save weight. Typically I use 2900-3200 mah per flight and land after 6 1/2-7 minutes of flight time with 37.6-37.8 volts/10s 4400 mah pack left. Brenner if you are still reading all this, please share your thoughts. I'm thinking my flying style and equipment is overwhelming the 4400mah 10s pack and need to move-up to a 5000-5300 mah 25c 10s pack combo. Thanks again Brian, Everette

wattsup

My Feedback: (1)

Hi Ed, I see you are interested. Do you mind sharing your thoughts including the batteries you have had success with? Thanks, Everette

wagen017

2900 - 3200 mAh out of a 4400 pack IMHO should be no issue at all. My flights are all around that, max to 3500. I now fly Hacker C50, before that with the Pletty 30-10 i would use 10-20% more, then a 4400 was borderline.

Volkert

wattsup

My Feedback: (1)

Volkert, let me also add, I average these numbers with both of my planes. The older of the two is equipped with an Axi 5325-24 outrunner/APC 21x13.5 e prop (my practice plane) and the newer plane is equipped with one of Brenner's Contra-Drive/ Neu F3A motors. Both have a Castle 80HV controller. Even though there is no real comparison between the two, I try to fly the Master's pattern as nearly the same as I can with both. Both have an AUW of approx 10 lbs 6 oz with the 4400 mah 5s battery packs. Just thought you might want to know more specifics, Everette

wattsup

My Feedback: (1)

Hey guys, would all or most of you tell us about your experiences both good and bad that you have had with the different makes of lipos. Please don't be shy, my intent is to not talk about just me but, to open this subject up to everyone who is willing to participate. All of us have alot to gain if we can only sort out the good reliable lipo batteries from the junk! Everette

serious power

Hi Everette,
With usage per flight at 3200 and those finishing voltages you should never really hurt the packs - even 4400's and being 40C load should be no problem.
There is something to this though - whatever it is ??

I have a 4350 -almost 3 years old. This I got to keep me legal with a Ventura.
For the first season I spared it for comps and practice in the week leading up to them.
Last year I used a bit more but not as much as my 4900/5000's.
This year I used it quite a lot.
It is tired now, but only recently and after I over discharged it badly in a new bipe in strong wind.
It took 4590mA back in - it had 150+ flights at that stage and I was a bit casual about it.
About 15 cycles later I over did again - similar situation but this time it took only 3950 to refill from a slightly lower voltage. So in a few cycles it lost a lot of capacity - due to abuse.

One of our group has per flight usages in and around 3200mAh on 5000's.
He gets unbelievable cycle no's, and always has apart from the first packs we got.
His packs at 100,150 and even 200 flights are just like new - again TP's and F3AU's.
I mean like new - square,firm and no puffing.
He does one other thing that the rest of us don't ,not to the same extent anyway - He fly's a lot.
His packs never lie around - if it is at all flyable he's out.
He get's hundreds of flights from all of his packs - all the brands he uses. Even with the first poor ones that we got he got the best usage. I have no reason,what so ever, to exaggerate here.

What brand are you using now.

Brian

wattsup

My Feedback: (1)

Brian, the 4400 mah 40c 5s packs I currently use and have worn out are the Sky Lipos. BTW, like your friend, I am able to fly almost everyday weather permitting. Consequently, my packs don't lay around either. I hesitate telling you about my other sets lipos I use because they are made available here in the USA and I really don't want to step on anyone's toes or create ill feelings. Again, as I said earlier in this thread, I've yet to get more than 70 flights out of ANY of the packs I have ever used. When you think about it, it's pretty sad because in the long run, these 2nd rate manufacturers are only hurting themselves because if any are in it for the short run to only make a fast buck, they will be forced out of the market place. You know as well as me that word travels fast and wide in a small community such as pattern. Thanks, Everette

Jetdesign

My Feedback: (8)

I have an old set of Rhinos, they were my second packs and a little abused. They have been my most consistent packs of all, not the highest burst but they give good constant power throughout the flight.

I have lots of Zippy batteries that get a little puffy rather quickly. I feel like I definitely notice which packs have had a break-in, which is not many of them. The ones where I was able to take it easy for a few flights seem to have more power. With most, I have a hard time being patient for a break-in and end up using throttle by the second flight.

I have 20C and 30C Zippy packs, the 30C's have had the worst performance of everything I own - puffing the most and the soonest, with the biggest depletion of power delivery.

I have one set of Blue lipo. I tried to take it easy on them, had a few easy flights. Definitely not stellar performance, but they haven't died off as quickly as the Rhinos.

I believe I would be (or have been) better off with 3 sets of quality packs - likely from F3AU. It would be a lot easier to properly maintain 3 good packs and keep track of them, and I believe I would end up getting the most battery energy for my dollar in the long run.

I will use what I have for another season, or practice with them until they are worthless. It is hard to just discard 5-6 sets of working batteries, even if the performance is poor. But maybe I'll save a little money and feel generous one day and give them all to a pattern guy who is new to electric, and start fresh with 3 packs - no more, no less.

wattsup

My Feedback: (1)

Joe, you are truly a gentleman and a scholar! I really appreciate you stepping up and giving an honest assessment of your overall experience with the different lipos you have tried. If you don't mind me asking, which size/mah packs and C ratings have you been MOST successful with in the past? Also, are you talking about buying the new 35C packs from Chris at F3A Unlimited? I've yet to talk with anyone who has experience with them. Hopefully, they will be one of the answers to our situation/problem. Chris' lipo have gotten better with each new generation. You do understand that gathering all this information is only possible when people like you give up their time and knowledge for the benefit of others. Thanks Joe__Everette

Brenner

This year I flew TP 25C 5000s and 5400s, the new 35C packs from f3aunlimited, Turnigy nano technology 35C packs, and Zippy 25C Compact 5800mah packs.

All of these brands performed well for me, except the Thunderpower packs cost about twice as much as the other packs, but I'm sure the extra cost is due to their weight. The Thunderpower 25C 5400 packs weigh the same as the Thunderpower 25C 5000 packs, and both are the lightest of all that I tried. (1180g..)

However, If I have anough weight margin in my plane I think I will use Zippy 25C 5800mah packs, They weigh 1300g, but I can pull 4500mah out of them all day long and they never break a sweat. The most I've pulled out was 5200 mah, which took them down to 10%, but most of the time I land with 25% to 35%.

The extra capacity increases the effective C rating relative to 25C 5000 packs, so the perfromance is great, and I have complete freedom to adjust my flying style to whatever conditions I need to fly in. (25 mph crosswinds at Muncie for instance ..)

I can also charge them at 5C as well, which is important for me, because I like to charge and fly all day long with no more than two sets of packs.

If I can't make weight with the Zippy 5800s, then I'll use the Thunderpower 5400s.

Brenner ...

wattsup

My Feedback: (1)

Brenner, once again, you are THE man! This was exactly the current information I was hoping someone would come forward with and I can assure you many others were helped in the process. Between you, Brian, Joe and Volkert, it just does not get any better than this. I don't mean to sound like it's time to close out this thread. To the contrary, I hope your response will encourage others to come forward and share their current experiences. Collectively, all four of you brought credibility to this fledgling thread and like many others, I appreciate your contribution. Wish you all continued success, Everette

Bill Clark

I noticed theThunderpowers seem to have a longer cycle life too and hold up well throughout their life and of course they are lighter but the competition has certainly closed the gap on performance and life. the price gap is still big. apparentlyTP is going tostick with thehigher cost lower volume approach. I have a 8s 3900 prolite that has seen 300+ cycles in an Extra and now in my Wind 110 and is damn near as strong as the day I got it (it was broken in extensively) but is was twice the cost of some of the other brands mentioned. I think it really boils down to the cost. if they were all free most would use TP

J-P

My Feedback: (1)

I'm curious to know how you charge at the field your 5800 mah packs at 5C .......

Brenner

Hey J-P,

I have a pair of Revolectric Powerlab 8 Chargers that I use with a 1000W power suppply, which lets me charge two 5s packs at 25A each. I run the power supply with a 2000W Honda generator.

Brenner ...

J-P

My Feedback: (1)

Thanks for the info
I didn't knew the Honda was able to deliver the necessary 1900 W ....
I will try
Thanks
JP

wagen017

At our flying spot we have installed a small solar panel powered charging station which dripfeeds a set of 24 V batteries. At first I was sceptical (it was an old installation we recycled) but it works great with a max Amps of 100. Charging at 20A requires a primary Amps of about 35A. Actual input voltage is between 24-28V depending on the amount of sun shining! This is true "green" flying :-)