Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Power Systems
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Power Systems Talk about motors, ESC speed controllers, gear drives, propellers, power system simulators and all power system related topics

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 08-19-2012, 03:43 PM   #1
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default Twin LiPo packs in parrelel

I'm about to mount split LiPo packs to my F16 pusher ... I have various packs that are too small for my regular use now and wish to use them on the depron F16.

I have 2 x 800mAh 3S 20C packs and 2 x 1300mAh 3S 25C packs ...

Idea is to sit one each side of the fuselage spine splitting the transverse weight. They will be via a Y lead to the ESC.

I have this strange idea that doing this will effectively give me a greater gross C rating ... plus an effective doubling of capacity ...

ie 2 x 800 would give me 1600mAh 20 + 20C ... or 2 x 1300mAh give me 2600mAh 25 + 25C

It gives me easier positioning to balance model and also splits the weight carried per mount.

What does the panel think on this ?

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-19-2012, 04:08 PM   #2
Dr Kiwi
Super Contributor
 
Join Date: Aug 2005
Posts: 1,726
Thanked 180 Times in 174 Posts
Awards Showcase

Outstanding Contributor Award 
iTrader: (0)
Friends: (3)
Default

2x800 will give you 1600mAh @ 20C (potentially 32A)... 2x1300 will give you 2600 @ 25C (potentially 65A).... you can't win both ways.
Dr Kiwi is offline  
  Reply With Quote
Old 08-19-2012, 06:16 PM   #3
road king 97
old hat
 
road king 97's Avatar
 
Join Date: Nov 2010
Location: joliet il
Posts: 2,634
Thanked 193 Times in 189 Posts
Club: joliet rc club rt 66
Awards Showcase

Scratchbuilders Award  Outstanding Contributor Award 
iTrader: (0)
Friends: (14)
Default

I was running 4 - 7.4 motors in parallel with two 3 cell 3200 lipo packs and still getting 11.1 volts with the same c rating but i had to run mine in series so i was getting 22.2 volts divided by 4 brushed motors for my plane to fly off of the water right. So i may be wrong but i dont think so ,you can run them in parralell and it wont change the c rating or the 11.1 volts but if you change it to series like i had to it will double every thing.Trucks do this alot to run two batterys without blowing up it's 12 volt system. joe


Attached Thumbnails
Click image for larger version

Name:	Img_7086.jpg
Views:	52
Size:	28.1 KB
ID:	161984
road king 97 is offline  
  Reply With Quote
Old 08-19-2012, 06:59 PM   #4
slipstick
Super Contributor
 
Join Date: Oct 2005
Location: N.Staffs, UK
Posts: 2,350
Thanked 197 Times in 191 Posts
Awards Showcase

Outstanding Contributor Award 
iTrader: (0)
Friends: (1)
Default

You can never change the C-rating. It is the rating of each individual cell. If you have 20C cells any pack made from them, whether connected in series or parallel or any combination, will always end up as a 20C pack .

Connecting in series or parallel will change the total voltage OR the total capacity (mAh) but never the C-rating.

Steve
slipstick is offline  
  Reply With Quote
Old 08-19-2012, 07:09 PM   #5
road king 97
old hat
 
road king 97's Avatar
 
Join Date: Nov 2010
Location: joliet il
Posts: 2,634
Thanked 193 Times in 189 Posts
Club: joliet rc club rt 66
Awards Showcase

Scratchbuilders Award  Outstanding Contributor Award 
iTrader: (0)
Friends: (14)
Default

I did not know about the c rating changing or not but thanks i do now. I have tore out all four brushed motors ,cut a slot from motor to motor to rewire it and bought brushless motors for it now. I had to cut into my planked neccels but in the end it will be worth having more power while using less battery . So he can run in parallel and it wont double the volts but it will double the (mah) ? Iam a prtty good builder but when it comes to esc's and batterys i get lost. lol joe
road king 97 is offline  
  Reply With Quote
Old 08-19-2012, 07:51 PM   #6
JetPlaneFlyer
Super Contributor
 
JetPlaneFlyer's Avatar
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 4,311
Thanked 476 Times in 444 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (8)
Default

Originally Posted by slipstick View Post
You can never change the C-rating.
+1... nothing you can do will change the c rating but if you wire the batteries in parallel then you do double the total Amp rating due to the current being split between the two packs.

PS, Road King.. Connecting batteries in series doesn't "double everything", far from it. All series connection does is double the voltage, the mAh capacity and c rating remain the same. Parallel connection on the other hand will double the mAh capacity, but voltage (and 'c') remains the same as the single pack.
JetPlaneFlyer is offline  
  Reply With Quote
Old 08-19-2012, 08:07 PM   #7
road king 97
old hat
 
road king 97's Avatar
 
Join Date: Nov 2010
Location: joliet il
Posts: 2,634
Thanked 193 Times in 189 Posts
Club: joliet rc club rt 66
Awards Showcase

Scratchbuilders Award  Outstanding Contributor Award 
iTrader: (0)
Friends: (14)
Default

Originally Posted by JetPlaneFlyer View Post
+1... nothing you can do will change the c rating but if you wire the batteries in parallel then you do double the total Amp rating due to the current being split between the two packs.

PS, Road King.. Connecting batteries in series doesn't "double everything", far from it. All series connection does is double the voltage, the mAh capacity and c rating remain the same. Parallel connection on the other hand will double the mAh capacity, but voltage (and 'c') remains the same as the single pack.
I thought the mah doubled also but iam learning more and more about running in series every day. I have plans for a 84inch wingspan twin otter and the same size albatross this winter ,both going brushless .I love multi motor planes and electrict is the only way to go but i need to learn more about wirering and electrict set up's.
road king 97 is offline  
  Reply With Quote
Old 08-19-2012, 08:37 PM   #8
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

Originally Posted by road king 97 View Post
I was running 4 - 7.4 motors in parallel with two 3 cell 3200 lipo packs and still getting 11.1 volts with the same c rating but i had to run mine in series so i was getting 22.2 volts divided by 4 brushed motors for my plane to fly off of the water right. So i may be wrong but i dont think so ,you can run them in parralell and it wont change the c rating or the 11.1 volts but if you change it to series like i had to it will double every thing.
I realise that each CELL wont change it's C rating ... but we will have 2 packs feeding simultaneously ... so I would have expected a better return ..

Trucks do this alot to run two batterys without blowing up it's 12 volt system. joe
Sorry but must disagree there ... I've driven , owned and been around trucks in my own company as well as contracted. Any serious truck is a 24V system NOT 12V. Second any truck that is 12V and has twin battery set-up as some of the older and smaller do - they are PARELLEL or split to power various items separately at 12V. You cannot squeeze 24V into 12V !!

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-19-2012, 08:40 PM   #9
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

Originally Posted by slipstick View Post
You can never change the C-rating. It is the rating of each individual cell. If you have 20C cells any pack made from them, whether connected in series or parallel or any combination, will always end up as a 20C pack .

Connecting in series or parallel will change the total voltage OR the total capacity (mAh) but never the C-rating.

Steve
I'm well aware of the voltage / capacity side of series / parellel ...

I'm just surprised that 2 packs supplying at same time won't give a better output. One thing I know I will get is a better load voltage .. maybe only a few decimals better - but something.

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-19-2012, 08:43 PM   #10
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

Originally Posted by JetPlaneFlyer View Post
+1... nothing you can do will change the c rating but if you wire the batteries in parallel then you do double the total Amp rating due to the current being split between the two packs.
That's my thinking on the amps potential ... two packs are now doing work of one .. less effect of resistance etc.

PS, Road King.. Connecting batteries in series doesn't "double everything", far from it. All series connection does is double the voltage, the mAh capacity and c rating remain the same. Parallel connection on the other hand will double the mAh capacity, but voltage (and 'c') remains the same as the single pack.
exactly.

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-19-2012, 08:55 PM   #11
JetPlaneFlyer
Super Contributor
 
JetPlaneFlyer's Avatar
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 4,311
Thanked 476 Times in 444 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (8)
Default

Originally Posted by solentlife View Post
That's my thinking on the amps potential ... two packs are now doing work of one .. less effect of resistance etc.

Nigel
It makes sense when you consider that the amp limit of a battery pack is calculated by:

Maximum Amps = c rating x amp-hour capacity

So while you cant change the c rating it's still true that if you double the amp-hours (e.g. by connecting in parallel) you also double the maximum safe battery amps.
JetPlaneFlyer is offline  
  Reply With Quote
Old 08-19-2012, 09:42 PM   #12
road king 97
old hat
 
road king 97's Avatar
 
Join Date: Nov 2010
Location: joliet il
Posts: 2,634
Thanked 193 Times in 189 Posts
Club: joliet rc club rt 66
Awards Showcase

Scratchbuilders Award  Outstanding Contributor Award 
iTrader: (0)
Friends: (14)
Default

Ok thats enough for me before i get a headacke .lol I have a guy who wired his big seaplane like i will with my new brushless set up and he will send me a wiring diagram. . I will have to run two batterys to get my CG correct. Thanks for the imfo guys. joe
road king 97 is offline  
  Reply With Quote
Old 08-19-2012, 09:46 PM   #13
slipstick
Super Contributor
 
Join Date: Oct 2005
Location: N.Staffs, UK
Posts: 2,350
Thanked 197 Times in 191 Posts
Awards Showcase

Outstanding Contributor Award 
iTrader: (0)
Friends: (1)
Default

Originally Posted by solentlife View Post
I'm just surprised that 2 packs supplying at same time won't give a better output. One thing I know I will get is a better load voltage .. maybe only a few decimals better - but something.
Two packs in parallel doubles the capacity. Since the maximum current is given by capacity x C-rating then twice the capacity gives twice the current (even at the same C-rating).

In the same way if you connect 2 x 2200mAh packs in parallel you get a better load voltage than one 2200mAh pack. But almost certainly no better than if you had a single 4400mAh pack .

Steve
slipstick is offline  
  Reply With Quote
Old 08-20-2012, 10:07 AM   #14
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

OK - my fault guys ... I fell into the C trap ....

I'm old school where we talked amps, volts, watts, mAh ..... and I often fall into using the term C when I mean amps ... ( I know the difference - it's just old habits die hard !)

So let's reword what I'm getting at ... (which appears to be confirmed by more learned in this thread) ...

A 800mAh 20C pack will punch out 20 * 0.8 = 16A in theory but we all know that if it does - it aint gonna like it !
Now 2 x 800mAh 20C packs in parellel will punch out 2 * 20 * 0.8 = 32A ... again same applies about max etc.

But now we have a power pack that can deliver a good punch (amps) to power my F16 pusher, plus have technically 1600mAh on tap ... and be able to use redundant packs, split the weight for cog / mounting etc.

Sorry for not correcting the C bit before ..

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-20-2012, 02:06 PM   #15
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

OK ... I tried it out with my 50mm Jpower T45 .... 2 x 800mAh 3S 20C packs.

On a single 800mAh 3S 20C - it's never been much - flies but needs more oooomph ! anyway this is a bench comparison not flight. The single was OK ... but nothing special.

On a single 1300mAh 3S 25C, which actually flies a Jpower well - it was moderate to good ... flyable.

On a single 2280mAh 3S 35C - this is getting better !

Now I went back to the 800mAh packs but now in parellel ... amazing difference .. it sounded more like a 4S in there ! The audible increased rpm was seriously higher.

I now have a new source of power using up what were redundant packs ! The packs are plugged into a Y deans lead I made up with decent gauge wire taken from a couple of 4S packs that went swanny ! So I have them still as singles, or doubled up ....

Ok - figures as per Wattmeter, on a 5000kv Turnigy 2615 EDF motor, 6 blade 50mm unit, Jpower T45 :

1 x 800mAh 3S 20C : 17A, 160W (Turnigy Flightmax)
1 x 2280mAh 3S 35C : 29.5A, 300W (GE Power)
1 x 1800mAh 3S 25C : 32A, 350W (E-Fly)
1 x 2100mAh 3S 35C : 34A, 385W (Turnigy Flightmax)
1 x 1500mAh 4S 25C : 46A, 630W (Zippy compact)
1 x 1600mAh 4S 35C : 49A, 700W (Zippy compact)

Now to the parellel figs for the 800mAh packs, I cannot carry bigger than that doubled up so only one set of figs ...

2 x 800mAh 3S 20C : 29A, 295W

So the doubled up pack near equalled the 2280 3S pack in amps / watts. More than I expected in fact.

Figs do show though that some of my packs may be due for retirement !!
Very happy !

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-20-2012, 07:20 PM   #16
JetPlaneFlyer
Super Contributor
 
JetPlaneFlyer's Avatar
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 4,311
Thanked 476 Times in 444 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (8)
Default

Yeah, it looks like some of your batteries are ready for in incinerator. Bear in mind though on some of them you are pushing over their max rated amps so voltage sag is to be expected. The 2100mAh flightmax looks pretty decent, the 800mAh and 2280mAh batteries would be in the trash if they were mine as they are almost at my LVC setting (3.3v) when straight off the charger (even when the 800's are paralleled up)

I usually look for a fresh battery to hold 3.75v per cell when loaded close to it's c rating, but it depends on your application. If they are installed in a model that doesn't pull many amps they could soldier on a bit longer.
JetPlaneFlyer is offline  
  Reply With Quote
Old 08-20-2012, 07:32 PM   #17
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

Originally Posted by JetPlaneFlyer View Post
Yeah, it looks like some of your batteries are ready for in incinerator. Bear in mind though on some of them you are pushing over their max rated amps so voltage sag is to be expected. The 2100mAh flightmax looks pretty decent, the 800mAh and 2280mAh batteries would be in the trash if they were mine as they are almost at my LVC setting (3.3v) when straight off the charger (even when the 800's are paralleled up)

I usually look for a fresh battery to hold 3.75v per cell when loaded close to it's c rating, but it depends on your application. If they are installed in a model that doesn't pull many amps they could soldier on a bit longer.
I'm terrible on batterys as I have to budget seriously .... with rebuilding house and various other commitments - it means I buy as cheaply as I can .. often on the C limits.

But saying that ... the 2280 G Power is near 2years old and was supplied with my RTF 450 Heli. It still flies that well ... it also flies my Skyartec Cessna 182 a treat ... giving me well over 11mins at majority WOT.
The other packs except the 800's serve various models that don't have great demands .. so they soldier on fine.
Where I do have obvious limits occurring is with my EDF's .. as we all know - they demand maximum C rating .... many of my packs come out of them hot. But they keep on trucking !

I agree that the 2100 Flightmax are good ... they are putting up with serious abuse in my 64mm T45 ....
The Compact 4S's .. also do well ... pushing my 50mm T45 to it's frame limits.

I have a new batch of lipo's on the way .....

Cheers
Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-21-2012, 02:56 AM   #18
hayofstacks
Super Contributor
 
hayofstacks's Avatar
 
Join Date: Jan 2012
Location: Utah
Posts: 1,553
Thanked 114 Times in 113 Posts
iTrader: (0)
Friends: (5)
Default

On my dad's advance, we were running two 1800's in parrelel instead of the recommended 3200 mah battery. This gave us a 90 amp continous and something like 154 amp peak using the c ratings, while being lighter. The performance was nevery really good on 3 cells, but had about 20 more amps with two batteries vs a 2200mah with a slightly higher c rating. My dad trashed the plane, so we will have to come back to it later.

I've been tempted to try 2 in parrelel and the put them in series where we have 7 of the batteries to test a 6 cell setup.
hayofstacks is offline  
  Reply With Quote
Old 08-21-2012, 02:58 AM   #19
hayofstacks
Super Contributor
 
hayofstacks's Avatar
 
Join Date: Jan 2012
Location: Utah
Posts: 1,553
Thanked 114 Times in 113 Posts
iTrader: (0)
Friends: (5)
Default

I like my batteries amp rating to be about double the max of the motor. Running the 30c 1800's on my 450 sport motor, I get exactly the same amps/watts that heads up reccomends.
hayofstacks is offline  
  Reply With Quote
Old 08-21-2012, 06:17 AM   #20
JetPlaneFlyer
Super Contributor
 
JetPlaneFlyer's Avatar
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 4,311
Thanked 476 Times in 444 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (8)
Default

One of the problems with c-rating is than some manufacturers seriously exaggeration their batteries c rating. In my experience HobbyKing are one of the worst offenders. With the possible exception of the Nanotechs I find all their brands are way over-rated. I treat them all as being in the 15-20c range regardless of what's marked on the sleeve, and this pretty much consistently bears out in practice.
Nigel's Numbers shown above also bear out my theory because any battery there that is exceeding 20c suffers very bad voltage sag. Even the likes of the 1600mAh 35c Zippy Compact, which must be quite new, and should in theory be perfectly good for the 49A that's being pulled from them are sagging down to 3.57V per cell when fresh off the charger.
JetPlaneFlyer is offline  
  Reply With Quote
Old 08-21-2012, 09:40 PM   #21
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

It's funny you mention nanotechs ..... all the guys I know who used nanos have now gone of them and back to standard Turnigy / Flightmax LiPo's ... having found their nanos were seriously less performance after a month or so. It was not just one guy ... so unlikely that their routine or care of battery was reason.

I have to admit that I am hard on batterys .. I never storage charge, I keep them charged at all times. I try to rotate my packs so I don't just use same one each day ...

I have particular packs for a particular model ... and most are pairs

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 08-21-2012, 10:27 PM   #22
JetPlaneFlyer
Super Contributor
 
JetPlaneFlyer's Avatar
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 4,311
Thanked 476 Times in 444 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (8)
Default

Originally Posted by solentlife View Post
It's funny you mention nanotechs ..... all the guys I know who used nanos have now gone of them and back to standard Turnigy / Flightmax LiPo's ... having found their nanos were seriously less performance after a month or so. It was not just one guy ... so unlikely that their routine or care of battery was reason.
Nigel
Nigel,

That was exactly my personal experience. The Nanos I had started to go off after 20 cycles and were junked by 60 cycles, and I know others with similar experience with numerous Nanotech batteries. But I've also come across some who swear by them and tell me they have loads of cycles and they are as good as new.... go figure

Maybe they are especially sensitive to abuse and only last if you treat them with great care?.. I'm clutching at straws because I've never killed any other battery anything like as quick as I killed the nanos.

Steve
JetPlaneFlyer is offline  
  Reply With Quote
Old 08-21-2012, 10:34 PM   #23
dahawk
Super Contributor
 
dahawk's Avatar
 
Join Date: Jul 2011
Location: Keller, TX
Posts: 3,346
View dahawk's Gallery6
Thanked 203 Times in 199 Posts
Club: 114th RC Aero Squadron
iTrader: (0)
Friends: (19)
Default

Dang, What a good discussion. I'm learning something here. Makes me wish I never sold my MG-C with twin 6V batteries to one Lucas alternator.

All kidding aside, I'm surprised to hear mixed results on the Nanotechs. Though I personally think Gens Ace are truer to their ratings, I have had no problems with the Nano's or their little brother, the Zippy's. Like oil, I think they all come out of the same hole. Slap a different name on them? Does one Chinese Lipo maker have a better process than another? Better materials? Better assembly?

As I understand it, the main reason to go with twin batteries in the F-16 at all was balance, right?

Wounded Warrior Fun Fly - Aug 16th ,2014 - Grapevine TX - Info link: https://support.woundedwarriorprojec...ising/RCPilots
dahawk is offline  
  Reply With Quote
Old 08-22-2012, 01:11 AM   #24
hayofstacks
Super Contributor
 
hayofstacks's Avatar
 
Join Date: Jan 2012
Location: Utah
Posts: 1,553
Thanked 114 Times in 113 Posts
iTrader: (0)
Friends: (5)
Default

Ballance and already had atteries. I am a fan of using what I already have, if it fits the requirements.

I have several turnegy battery's we bought used at a yard sale for a couple bucks a peice. They hold a charge well, but don't last as long as some of our others. Have no ide the history behind them though.

7 out of 8 of my heads up 1800 mah's are still going strong. My 8th one went through the prop of my slow stick. One or two that we recovered from low voltage are starting to show some degredation though. I never store charge, and almost never charge them back up right away. My old 25c 1800 has benn through I estimate 300 cycles. I flew it almost esclusively with my slow stick and has been in 5 or 6 planes since.
hayofstacks is offline  
  Reply With Quote
Old 08-22-2012, 10:42 AM   #25
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 5,896
View solentlife's Gallery47
Thanked 231 Times in 228 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

Originally Posted by dahawk View Post
.............
As I understand it, the main reason to go with twin batteries in the F-16 at all was balance, right?
Yep - but got me thinking that maybe others have similar situation of battery packs idle and no model to use them in ... as we all know on the 50mm series mini jets - first thing you do is replace the silly 800 3S with a decent sized pack with a greater C rating .... then she rocks ! What to di with the small packs ?

I have 2 x 800 20C and 2 x 1300 25C packs on 3S ... ideal for the F16 pusher.

Judging by the results above .. you could even with good packs improve your power system by pairing up your lower rated usual batterys ? The 50mm T45 for example can carry a twin 800 system ... that means your original packs are back in business and giving you similar performance to a good rated 1600 battery.

I'm interested to know if anyone else uses this route ? And what experiences out there ?

Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Power Systems

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
New Product MaxAmps.com 8000mah Dual Core 150C LiPo battery packs brandonwilcox Maxamps discussion 13 07-08-2012 08:01 PM
Solid experience on RC Model Lipo Battery Accident & Charger Guide SimonXi Batteries & Chargers 0 08-12-2011 05:08 PM
Not All Balanced LiPo Packs Are Equally Balanced Swift428 Batteries & Chargers 9 03-29-2011 09:26 PM


All times are GMT +1. The time now is 05:04 AM.


Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.35484 seconds with 70 queries