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Author Topic: Poor battery life  (Read 4037 times)

Offline Dick Carville

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Poor battery life
« on: June 23, 2013, 03:45:15 PM »
Folks I could use your help with this problem.

Last year I used Arrowind motor 3226-685KV and  TP 5S ,2700 MAH,  25C batt

 I Could only get about 25 or 30 flight until I started getting  a “soft shutdown” at the end of the flight or in the clover and could not use the battery any longer

This year I switched to Scorpion motor and Genesis batt   -- same problem at 20 flights  on the batt I get a “soft shutdown “prior to the true FM9 cutoff at 5:40  flt time.   I Don’t see the problem on batteries with less than 20 flights on them

Both set ups use a Castle, ICE 50 controller and  FM9  timer

All flight time set for 5 minutes 40 seconds


I don’t hear others complaining of only 20 flights per batteary  so I must have something messed up


Can you help??

Here’s my specs;
Motor : Scorpion 3026-710 KV

Batt: Genesis 5S,  2800 MAH, 40 C

Motor settings:
 Timing:  5 per motor Mfgr
PWM : 8Khz per motor Mfgr


Cutoffs:

Auto Li-Po   3.2 V   ( changed this to 3.0 V with only a slight delay of the “soft cutoff”)

Current limiting : Sensitive  (60A)

Governor  Gain:  36

Head speed change:   8



Prop APC 13X4.5   old style – F2B


RPM  around 9400


Battery usage  about 1950 with wind about 2170 with no wind

Plane is an SV 11 weight about 66 OZ--  Flys Great !

Online Crist Rigotti

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Re: Poor battery life
« Reply #1 on: June 23, 2013, 05:47:30 PM »
Maybe a heat problem?
Crist
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Offline Curare

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Re: Poor battery life
« Reply #2 on: June 23, 2013, 07:16:39 PM »
What charger are you using?
Greg Kowalski
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Offline William DeMauro

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Re: Poor battery life
« Reply #3 on: June 23, 2013, 07:54:14 PM »
Are you storing the batteries charged?
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Offline Dean Pappas

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Re: Poor battery life
« Reply #4 on: June 23, 2013, 08:41:56 PM »
Hi Dick,
Hmmm ...

For starters, the numbers need to start agreeing. Right now, the only consistent thing is that packs go west on you after only a few dozen flights.

1
For starters, charge a pack that has demonstrated the problem ... you are using the balancing feature, right??? ... and then immediately afterward check each individual cell voltage for balance and a full 4.20 +/- 0.03V.
2
Put in a flight and after the annoying slowdown, set the pack aside for a full 1/2 hour, so the cells revover their post-flight resting voltage and THEN read each individual cell and report.
We will be trying to figure out whether you are really pulling the battery down lower than the 70% used that your charger is reporting.
3
Have you messed with any datalogging? Please log the voltage, current and total capacity used at the once per second rate.
At first, don't turn on any other recording parameters because we don't want to tax the ESC's processor. Then let's look at the data.
4
Take a good look at your setup: are there any sources of unwelcome electrical resistance in the path from battery to ESC?
The currents we run can cause big voltage losses under maneuver loads.
Which deadman switch (if any) are you using?
Are the connectors all crudded up with spark welds?
Are the wires long?
Are the solder joints clean, or are there possibly some cold joints between battery and ESC? Bad crimps if that type connector?
5
Question ... just before the cutoff, how is the power? Do you suspect that the ESC is lying about the undervoltage or not?

We are on the case!
take care, and fly carefully so as not to lose the ship.

Dean
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Offline Dick Carville

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Re: Poor battery life
« Reply #5 on: June 24, 2013, 11:13:49 AM »
Guys

Thanks so much for your responses. I see there are a lot of things I can check that I have not thought of.

I’ll respond to each of your questions and ideas:

Chris

It could be heat but, it seems to do the same
  on cool days as well.

I have had the logging turned off after initial flights so I don’t know the current temp of the controller. It was running about 100 degrees. I have the ESC suspended directly in the nose air inlet

I’ll log it again after I do Dean’s tests

The battery comes down cool on cool days and only slightly warm on 90-degree days. When warm I can put it on my cheek and not be burned-- Don’t have temp
Gage

Curare

Charger is Thunder Power  610C –ACDC.   It has a feature that will not allow charging to start if any cell is below 3..2 volts .  I have not had a failure to charge—YET.   

I’m charging at 3.6 A

Will

Per your suggestion, I do not store the batteries charged. I do charge them the night before I plan to fly and if I don’t fly I discharge them



Dean

I do balance every time I charge

Since I flew last night and the batt. had not yet been touched after the  flight I checked the V/Cell
 1) 3.7 ,  2) 3.7,   3) 3.8 ,  4) 3.8,   5) 3.8

I then charged the batt .   it took 2106 MAH

V/ cell after charge:  1) 4.194; 2) 4.192;  3) 4.203;  4) 4.196;  5) 4.184

I’ll repeat this test Wed. night when I fly again

I  had logging turned off . I now have it set to record volts and current for Wed flying


All wire is standard length except the ESC to motor wires that I shortened

I solder pretty well so I think the joint is good



All other wire came pre soldered and is covered with shrink tubing including the battery - all look ok from the outside-- No crimps in the system

Safety switch is Maxx products ,Deans connectors.  All look clean not burned and I’ve swapped the plug out three times –just because


The power seems fine just before cut off is triggered.  I do suspect something other than the battery

I’ll collect more data Wed night and report

The SW in the ESC is 3.27

Thanks again to all

Dick

Offline Dean Pappas

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Re: Poor battery life
« Reply #6 on: June 24, 2013, 12:17:58 PM »
Hi Dick,
Do you have another voltmeter that lets you look at those post flight voltages with at least two decimal places of resolution?
Either the cells are all unbalanced by as much as a tenth of a volt, or they are all crowded around 3.75 V. We just can't tell with those numbers.

The chase is on. #^

Dean
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Offline Doug Moon

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Re: Poor battery life
« Reply #7 on: June 24, 2013, 01:02:19 PM »
Will

Per your suggestion, I do not store the batteries charged. I do charge them the night before I plan to fly and if I don't fly I discharge them

Thanks again to all

Dick

I have been told specifically NOT to discharge.  If you do be very careful as you can damage them. Storing charged for a while while you wait to go flying is ok.  Once done flying if you aren't going to fly again for a while then charge to the sotrage setting on your charger.
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Offline Dick Carville

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Re: Poor battery life
« Reply #8 on: June 24, 2013, 02:22:44 PM »
Dean

Don't know why I dropped the last two  digits- too many numbers for me I guess    !!
The numbers  at flight end are :
1    3.754
2    3.784
3    3.812
4    3.806
5    3.802

Offline Russell Bond

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Re: Poor battery life
« Reply #9 on: June 24, 2013, 05:56:18 PM »
100c on the ESC is too hot.

I was told by Castle that the ESC shuts down at 100c.
Bandolero

Offline Dean Pappas

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Re: Poor battery life
« Reply #10 on: June 24, 2013, 08:03:24 PM »
Dean

Don't know why I dropped the last two  digits- too many numbers for me I guess    !!
The numbers  at flight end are :
1    3.754
2    3.784
3    3.812
4    3.806
5    3.802

Hi Dick,
Those voltages look like somewhere between 40 and 50% of capacity remaining.
I am only a little concerned to see almost 60 mV difference between the high and low cells, but this is probably not the problem.
I would have loved to have these numbers for the pack when it was new: maybe it is a significant change in 20 flights.
Try charging at the 1C rate to see if that spread tightens up, but I don't think you are suffering from one wimpy cell in the pack.

Regards,
Dean
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Offline Russell Bond

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Re: Poor battery life
« Reply #11 on: June 24, 2013, 08:56:21 PM »
Mmmm, was it 100F or 100C?
Bandolero

Offline Dick Carville

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Re: Poor battery life
« Reply #12 on: June 25, 2013, 07:56:14 AM »
Russell

It was 100 degrees F on the ESC

Dean

I have 4 of these batteries and the newer  two have only about 10 cycles. I'll measure the # 1  oldest and # 4 newest and send comparison.

I am suspecting the Maxx switch . I had this issue on two set ups both with different batteries and motors . The only two common things  are the switch and the ESC

 I took a switch apart and it does have two  crimps on the end where the plug goes in. Both crimps look tight and well done, . Two ends use Deans and look fine. The plug in socket  looks suspicious to me. The two plastic pieces that are joined are restricted and captured buy the plastic, unlike the Deans springs these can lose tension and the plastic connection will not allow the spring to adjust.


Along with the other tests I have for tomorrow , I'll bypass the switch and see what happens

Dick




Offline Bob Hudak

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Re: Poor battery life
« Reply #13 on: June 25, 2013, 07:35:15 PM »
I don't think your disconnect switch is the culprit. You would lose all voltage(momentarily) and not have a slow shutdown.Now what about the lead going to the timer? It could pick up a false signal if too close to the ESC motor leads or battery leads. I haven't seen this happen yet but maybe somebody else has.
350838

Offline Dean Pappas

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Re: Poor battery life
« Reply #14 on: June 26, 2013, 09:00:16 PM »
It could be resistive, Bob. 10's of milli-Ohms are enough to cause grief.
Dean P.
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Offline Dick Carville

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Re: Poor battery life
« Reply #15 on: June 28, 2013, 12:10:18 PM »
Hi guys

After dodging T storms I finally managed to get in three flights before I had to quit.
I’ve been working on the data and trying to learn how to transmit it.

Data first then I’ll comment on what I think may be going on with these batteries.

I disabled the safety switch on the  first flt – no joy- it’s not the switch

Batt # 1 Had soft cut off  All capacities are 2800 MAH
            
Cell         1      2      3      4      5
Full         4. 192      4.191      4.198      4.194      4.186
After flt      3.747      3.747      3.778      3.769      3.801     MAH used 2035 

         21 cycles on batt #1

Batt # 2 Had soft cut off

Cell         1      2      3      4      5
Full         4.188      4.186      4.185      4185      4.181         
After flt      3.736      3.746      3.750      3.755      3.752    MAH used 2054

         
17 cycles on batt #2

 Batt # 3 Had a normal cut off

Cell         1      2      3      4      5
Full         4.198      4.190      4.199      4.197      4.193      
After flt      3.757      3.765      3.783      3.779      3.783     MAH used

9 cycles on batt #3

After looking at the ESC data one thing stands out:  Batt 1 &2 showed a momentary 14.9 volts ;  Batt #3 did not get that low ; 16.4 was its low.

How 1&2 can show 14.9 v when the after flt individual cell voltage adds to more than 18v is beyond me

I’ll attempt to attach scanned copies of the Castle data log

Next flights

I’m going change the cut off from LiPo auto to voltage and change it to 14.5 and see what happens. I think the controller may be seeing 14.9 as a cut off point even with each cell well above 3.2 v

I will also measure ESC heat – just in case that’s a factor

 The Castle notes on the “Current Limiting” function says it can also cause premature shut down when it sees a Ripple it does not like ( I don’t understand Ripple)   I’m reluctant to disable Current Limiting to test this , but I may have to at some point

Offline Dick Carville

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Re: Poor battery life
« Reply #16 on: June 28, 2013, 12:13:03 PM »
Castle logs

Offline Dick Carville

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Re: Poor battery life
« Reply #17 on: June 28, 2013, 12:15:55 PM »
Log  2

Offline Dick Carville

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Re: Poor battery life
« Reply #18 on: June 28, 2013, 12:16:30 PM »
log 3

Offline Bob Hudak

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Re: Poor battery life
« Reply #19 on: June 28, 2013, 08:12:26 PM »
Something is wrong with the data that your ESC is recording for batt #1. I calculated your flight time in seconds and came up with 7.33 minutes but you stated a 5.40 min. set run time. Also your rpm recorded data shows about 2400 rpm recorded but you stated it is set around 9400 rpm. I saw this happen once on a setup that was working but the recorded data changed like yours appears to have done. I had to re enter all the settings in the speed controller to fix the bad recordings. I can't remember if I had a early slow shutdown when this occurred.
350838

Offline Dick Carville

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Re: Poor battery life
« Reply #20 on: June 29, 2013, 05:53:32 AM »
Bob

Thanks for  the input.  My actual flight time is running at 5:40 .   If the time scale is in seconds your calculation looks correct, but does not agree with actual flight time.

The RPM logging was turned off.  The only thing I had turned on were  Volts and Current.  I don't know why RPM showed up.  The plane flew normal. I would have had lots of issues if RPM was that low.  9400 RPM was recorded with a tac at original set up but not checked each flight

Lots I don't understand , but will stay on the hunt. I will reset everything before the next flights ( tomorrow I hope)

Thanks

Dick

Offline Dennis Adamisin

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Re: Poor battery life
« Reply #21 on: June 29, 2013, 06:25:23 AM »
Hmmm  I do not think the answer is in the pack voltages.

Dick, you saiid one of the common threads was the ESC: Here's an oddity: Make sure the ESC is looking for LIPO's, not some other type, Make sure it is looking for 5S, not something else (I remember you were flying some 6S systems).  Make sure it has the cut-off voltage no higher than 3.2V/cell.
Denny Adamisin
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Offline Dick Carville

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Re: Poor battery life
« Reply #22 on: June 29, 2013, 07:18:41 AM »
Hi Dennis

The controller is set for 5S  lipo 15.5 V and the Cut Off was  set to 3.0 v per cell.

I now have it set for total volts  at 14.5 volts vs  Auto Lipo at 3.0 per cell to test  a theory. Since both  premature shutdown flights show  a bump down to 14.9 volts I think the ESC is  seeing that low volt and cutting off even though  each cell seems to be well above 3.5v


Very strange goings on

Dick

Offline Dick Carville

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Re: Poor battery life
« Reply #23 on: June 29, 2013, 07:21:21 AM »
Dennis

Typo set for 18.5 volts 5S

Offline John Rist

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Re: Poor battery life
« Reply #24 on: June 29, 2013, 08:03:51 AM »
I know I may be drummed out of the core for this comment - but what's wrong with a cheep speed controller (such as the Turnigy Plush) and a KR timer/governor?  Doesn't have data logging but doesn't need it because this setup seems to be trouble free.  And it doesn't take a degree in software engineering to get consistent reliable runs.   ???
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Offline Dick Carville

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Re: Poor battery life
« Reply #25 on: June 29, 2013, 11:25:19 AM »
Bob H

I think i figured out why the time is off on my flight #1 ; batt #1  log

I bet the controller is logging time from the time it's first is armed. In fact you can see the "dec" time on the chart.   The real  flight time is controlled by the Timer.
 On the first flight I by-passed the safety switch and had to spend a bit of time after arming to put the cowl back on and I think I even ran out the lines before coming  back to press the start button.

The other runs were:  put in plug, press button, and go.

Thanks for the comment I learned some more about how this ESC works

Dick

Offline Bob Hudak

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Re: Poor battery life
« Reply #26 on: June 30, 2013, 07:54:30 PM »
Dick,
 Just for kicks try turning on your throttle record feature. It may be able to show when the throttle goes low. I got a funny feeling something may be interfering with the throttle signal sent to the timer. I don't see the end of flight warning(500 rpm drop 5 sec. before the timer shuts the system down)where it's  supposed to be on your recorded data.
350838

Online Crist Rigotti

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Re: Poor battery life
« Reply #27 on: June 30, 2013, 09:13:37 PM »
After the cut off, how easy is it to feel every connection?  You're looking for a connection that gets hot.
Crist
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Offline Dick Carville

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Re: Poor battery life
« Reply #28 on: July 01, 2013, 12:07:53 PM »
Hi guys

 Got in 4 flights yesterday.

Auto Lipo at 3.0 v  per cell was turned off

Cut off voltage was set at 14.5 v . The charts on previous flights showed a  soft cut out at 14.9V

ESC temp turned on

Temp looked fine the high was 130F and only a spike, the average about 118F

Batt 1, 22cycles, batt 2, 17 cycles,,batt 3, 11 cycles . Batt 4, 10 cycles

Batt 1   got a more normal shut down   After about 8 laps following the clover it bumped and powered down after two laps. I have known this to be normal, BUT this was not completely normal. The bump and shut down were not as crisp as I see on the newer batteries—suspect low voltage

Batt 2 same as 1

Batt 3 normal shut down

Batt 4 normal shut down

I won’t bore you with the charts (unless someone wants to see one)

What this tells me is that the ESC looks for a 15.0 V min even when Auto Lipo is selected by cell.    Batt 1& 2 are dropping below that  value as low as 14.9 . 
When the low limit is  set to 14.5 it did not result in a soft shut down. Think it delayed shutdown long enough for the timer to shut it down

The Mystery??

When I check the “bad”  # 1 battery after flight the TP610C charger shows it at 18.680 V  total and every cell above 3.7 . This has been true after every flight

I could understand a low voltage spike if it was while the system is stressed in a stunt, but it’s happening after several level laps after the clover- Something to do with time?

QUESTION

When armed is the ESC supposed to beep signifying the number of cells it sees??  I seem to remember this from somewhere.

I benched checked this with both Batt # 1 and a TP 5S 2700 mah batt neither one gave cell count just a little happy tune   Should it count?

QUESTION

This is a tight install almost all wires touching others.  Could I be getting cross talk?


Next steps

The only thing I soldered were the bullet connectors on the motor. I removed shrink and all looked good, but I re-soldered all anyway. Good shiny joint – no voids , full cup

One flight with batt # 1 ; Genesis  5S 2800  40C

One flight with TP 5s 2700  25C

Turn on Throttle record (Bob)
   
Check voltage drop  across all flights on both batteries

Check for hot connections after flight (Chris)

Try to isolate the ESC a bit better from wires

Offline Dean Pappas

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Re: Poor battery life
« Reply #29 on: July 02, 2013, 08:03:30 PM »
Hi Dick,
As I look at all three of the voltage plots you attached the other day, it strikes me that your batteries are just a little undersized for this airplane: either in C rating or in capacity.
You are running substantially into the voltage droop at the end of the battery's charge.
See how the majority of the discharge is a very shallow belly-down curve and in the last 10% of the flight it transitions to a sharper belly-up curve?
That crossover or inflection point is ideally the place you'd like to be done with the schedule, if you were optimizing battery size, weight, and safety margin.
(Randy, did you catch this?)

sorry for the bad news. How much does the ship weigh, again?

Dean

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Offline Dennis Toth

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Re: Poor battery life
« Reply #30 on: July 03, 2013, 10:03:38 AM »
Dick,
One thing you might try is to reduce the prop diameter by 1/2 - 1". I had the same problem on one of my ships, I kept trying to push the diameter and finally had to do the prop change. If you clip the prop, round the corners and sand the last 1/16" of the tip angled up from the bottom to the top, if left square it may cause more drag then the diameter reduction creates. If the ships is a little slow pull in the lines 1 -2 ft. You might also try a different brand or style of prop to reduce the load.

Best,     DennisT
« Last Edit: July 03, 2013, 10:31:32 AM by Dennis Toth »

Offline Dick Carville

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Re: Poor battery life
« Reply #31 on: July 03, 2013, 10:29:58 AM »
Hi Dean


Thanks so much for taking the time to do the analysis you did.

I now believe I just have crappie batteries.

These Genesis batteries are marked 2800mah and 40 c, but I now question that. ( only using about 2060per flt)

The SV11 is about 68 oz

I did notice the speed controller in the SV11was not counting cells upon power up and started to suspect it .

My McFarland Akro Master   also has an ICE 50 controller and an FM9 timer but a Arrowind  motor vs the Scorpion in the SV11. It did do a cell count when powered up with the same battery.

The Akro Master is about 63 oz

 Today I put battery # 1 (fully charged ) in the Akro and  got the same soft shutdown after the clover.

Just crappie batteries I guess.

Now I’m lost.   I used the “ best” last year Thunder Power 2700 25C  on the Akro Master and had poor life . I did not keep a good count as I did this year but it was low

My first ST60 conversions use an Arrowind 6C and also had short life.

I love elect performance, but just can’t afford 20 to 30 flights per battery.  I know other folks do much better .

The planes fly so nice I'd love to find something that will give me 50 flight on a batt

Thanks for the help

Dick


Offline Dean Pappas

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Re: Poor battery life
« Reply #32 on: July 03, 2013, 10:39:46 AM »
Hi Dick,
i know that additional weight ain't no fun, but try going up on capacity to maybe 3300.
using less percent capacity is always good for the batteries.
So is doing a break-in on either a cycler or in the plane using no more than 40 or 50% capacity.
Do you suspect any particular reason you saw poor cycle life with the TP's last year?
Dean
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Offline Dick Carville

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Re: Poor battery life
« Reply #33 on: July 03, 2013, 12:02:00 PM »
Dean

The TP batteries last year seemed to last a bit longer than these new ones. I thought the 2800 mah and 40c vs  the TP 2700  and 25c
  would help longevity  but it seem it's worse. They were half the price of the TP so I guess I got what I paid for

I'm thinking of biting the bullet and buying ONE TP  3300 mah 45 C and see what happens.  It will make the Akro Master too nose heavy but the SV 11 is bordering on tail heavy now so the weight might be OK .  I was hoping for same batt both ships, but I guess not

Think the TP 3300  45C might work?

Dick

Online Paul Walker

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Re: Poor battery life
« Reply #34 on: August 01, 2013, 08:55:36 AM »
Try calling Thunder Power. They are very good at supporting their product. I had 2 of their 5S2700 65C batteries do this. I sent them to them and they confirmed that the battery was bad, and soon I had 2 brand new 70C batteries. Each of those had about  35 flights on them when they went. The remaining 4 have over 100 each  and are still fine.

Batteries are improving constantly. I used the "new" G8 5S2700 25C in my Predator at the Nats this year. That battery weighed just 10.5 ounces yet flew the 66 ounce Predator perfectly. They used  ~2200 per flight. We'll see how long they last, as I use about 2300 per flight at home. Small price to pay for that significant weight savings.



Offline Peter Germann

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Re: Poor battery life
« Reply #35 on: August 02, 2013, 03:57:47 AM »
...I had 2 of their 5S2700 65C batteries do this. I sent them to them and they confirmed that the battery was bad, and soon I had 2 brand new 70C batteries. Each of those had about  35 flights on them when they went. The remaining 4 have over 100 each  and are still fine.

Having gone trough a variety of batteries within three years, I have reason to believe that the C rate might influence the number of cycles you are getting. In my case, higher C has always given more cycles. Currently, I fly 4 ea. TP G6 Pro Power 2700 5S  65C. All have 30-40 cycles and look / function as new.
65 oz  5.3 sec/lap  64ft x 0.015 cables  APC 13 x 5.5 EP  9'553 RPM  5:30  AXI 2826/12 (760)  Ice lite 75A  low voltage trigger level set to 3.0V

regards, Peter Germann
Peter Germann

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Re: Poor battery life
« Reply #36 on: August 02, 2013, 01:42:46 PM »
That's interesting.  I bought three TP G6 Pro Power 2700 5S  65C batteries last year.  One went bad last fall, and the other two are failing now.  I haven't abused them much, and typically put 2100 to 2200 mAh back per charge.  Thunder Power replaced the first one free.  They'll probably replace the other two also, but their failure comes at an inconvenient time. 
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Offline Dick Carville

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Re: Poor battery life
« Reply #37 on: August 03, 2013, 06:41:11 AM »
Paul

Thanks so much for responding to my battery life issues on Stunt Hanger.

I was wondering about the new TP G8's . I was thinking about the 2700 70C. Your comments confirm that they should work OK . I was a bit reluctant to try them due to the price, but now I have some confidence.

I did go nuts and bought two TP 3300 45C  G6 that were discounted due to close out of the  G6 .

They are working fine. Surprisingly the planes ( an SV11 and my original Raven , about the size of an SV11) fly Ok with the 16 oz batt, but the batt is a pain to install due to length

I'm looking forward to even better performance when I knock 5oz off with the new G8 batt

Thanks again

Dick

Offline Alan Resinger

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Re: Poor battery life
« Reply #38 on: August 03, 2013, 07:39:31 AM »
Dick,
I was using the G6 5S 2700 25C battery all last year.  At the start of this year, 2 of the batteries developed bad cells.  I sent them back to Thunder Power for evaluation and they replaced them with the new G8 versions.  The G6 batteries had about 50 charge/discharge cycles.  Paul had ask me about them when we were in Portland early this year.  I since had 2 more of the G6 batteries go bad and Thunder Power replaced them also.  Spending money on good batteries makes sense when they warranty them like that.  I am now testing some new 3B props very similar to what Paul uses and the new batteries are being taxed like his with between 2200 and 2300 mAh being used per flight.  We'll see how the new G8 batteries hold up.
Alan Resinger

Offline Dick Carville

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Re: Poor battery life
« Reply #39 on: August 03, 2013, 03:19:53 PM »
Alan

Thanks for the info.

Last year I used the TP2700 25C G6 on my lighter Mc Farland  Akromaster. They worked well ,but I did not keep track of the cycles . I THINK I got about 40 or so ;maybe 50.

Two big mistakes I made were . I did not keep track of cycles and I did not keep receipts.

I won't make those mistakes again and plan to stick with TP

Thanks

Dick

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Re: Poor battery life
« Reply #40 on: August 03, 2013, 11:24:43 PM »
I was wondering about the new TP G8's . I was thinking about the 2700 70C.

I bought a couple of the 45Cs and have one 70C.  They are the same size (both are 1/8" narrower than the G6 65C), and same weight, which is the same as that of the G6 65C.  I use all three types interchangeably.  Although I need the weight in the nose, I don't need all those C's. 
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Offline Tim Stagg

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Re: Poor battery life
« Reply #41 on: August 04, 2013, 06:49:58 PM »
Dick,

I realize I may be the one that steered you to the Genesis batteries. I am still flying mine with no issues. NOt sure if you got some bad ones or what. I too went the T.P. route before the genesis batteries and paid $ 800.00 for 6 packs I think. They lasted about a season and then started to puff. They where the T.P. 2's that are 25C

I came to the conclusion that I was not running enough C's for my discharge rate so I jumped to the 65C on the Genesis batteries.

Here is what I am running for batteries/ Motor setup with success:

1. Genesis 3300 4S 65C, E-Flite 25 with Castle ice 50 and Fm9 timer 5 Minutes 30 Seconds time, using about 65% of capacity, according to my charger
2. Genesis 2800 5S 65C, E-Flite 32 with Castle ice 50 and Fm9 timer 5 Minutes 30 Seconds time, using about 70% of capacity, according to my charger

These are my 40 size and 60 Size setups, they work so I haven changed.....other than I think I am slowly deciding to standardize on the e-flite 25 setup and stay with that size airplane....The bigger planes just yank me around too much, and I am suffering lower back issues from Arthritis.

Anyway...don't know if this helps but I am sorry if I steered you in the wrong direction with the Genesis batteries.

Tim
Tim Stagg


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