What About Running A 10.5 Brushless On A 1 Cell Lipo,with Rec Pack.

What About Running A 10.5 Brushless On A 1 Cell Lipo,with Rec Pack.

Just run a two cell Lipo pack and a 17.5 or 13.5

Some of the 12th scale on road guy's have use a single cell lipo and a 3.5 and have gone 19t/ 4 cell speed.

Some of the 12th scale on road guy's have use a single cell lipo and a 3.5 and have gone 19t/ 4 cell speed.

I believe that Novak is comming out with a 21.5 motor so you can
run 2 cell Lipo pack and be at 19 turn speeds. :thumbsup:

But a single cell would be cheaper and you wouldn't have to worry about balancing.

IM LOOKING AT LOW COST LOW MAINTANCE SO I CAN WORK ON SETUP....AND RUN STOCK SPEEDS,, 19T IS TO FAST.ALOT OF PEOPLE ALREADY HAVE A 10.5/4300 THIS WAY YOU JUST NEED A LIPO CELL AND A 15-20 DOLLAR RECIEVER PACK ........THANKS FOR THE FEEDBACK :thumbsup:

The 21.5 Isn't Out Yet....im Thinking Of Another Brushless/lipo Combo In Case The 21.5 Is Not Out In Time.

Iceman,

I like the idea. simple, 1 cell lipo. No matching worries ever again! extremely light. I wonder if there would be some way electronically 'store' enough power to run the reciever/servo w/o an additional reciever pack..any ideas?

But a single cell would be cheaper and you wouldn't have to worry about balancing.

Where can you buy just one cell Lipo??

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=473 :wave:


Battery Chemistry Polymer Li-Ion
Electrical 3.7V, 6350mAh
Model 7548168
Max Charging Rate 3100mAh (0.5C)
Max Dis-Charging Rate 6300mAh (1C)
Cycle Life Up to 500 Times
Weight 120g
Dimension 169 mm x 49 mm x 8 mm

25.50$

I Ran The Single Lipo In One Of My Buggies Just In The Yard....[b]i Tried A Cap On The Esc And Rec It Wouldn't Work I Had To Run A Small 150 Mah Lipo Reciever Pack....I RAN A DECENT 4200 4 CELL RACE PACK AND THE SINGLE LIPO TO COMPARE PERFORMACE ON A 10.5 BRUSHLESS SYSTEM[NOVAK]....I MARKED OUT A OVAL IN MY DRIVE TO SEE THE DIFFERENCE 4 CELL 42 LAPS 1 CELL LIPO 35 LAPS IN 4 MINUTES....I DID IT 2 TIMES BOTH WAYS USING A ORION LAP COUNTER ............................NOW I KNOW THIS WAS A CRUED WAY TO TEST THE IDEA AND IM NOT THE GREATEST DRIVER BUT MAYBE THIS WILL PEAK SOME OTHERS TO TRY IT.... CLASSIC WILL OPEN IN A FEW WEEKS THEN I'LL KNOW REAL ON TRACK RESULTS BUT I REALLY THINK THIS WILL BE VERY CLOSE TO 27T STOCK USING THE 10.5/4300.

Lipo 3000HV 3.7V Loose Cell ONLY $26


NEW COPPER TAB CELLS!
3000mah Capacity
3.7 Volts
44mm X 134mm X 5mm
20C Constant(60 amps)
30C Sustained(90 amps)
50C Burst(150 amps)
73 grams
Typical Capacity is between 3000-3100mah www.maxamps.com

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=473 :wave:


Battery Chemistry Polymer Li-Ion
Electrical 3.7V, 6350mAh
Model 7548168
Max Charging Rate 3100mAh (0.5C)
Max Dis-Charging Rate 6300mAh (1C)
Cycle Life Up to 500 Times
Weight 120g
Dimension 169 mm x 49 mm x 8 mm

25.50$

no way I would put that in a car with those specs. Max discharge 1c you have to be kidding me can you say boom!

Lipo 3000HV 3.7V Loose Cell ONLY $26


NEW COPPER TAB CELLS!
3000mah Capacity
3.7 Volts
44mm X 134mm X 5mm
20C Constant(60 amps)
30C Sustained(90 amps)
50C Burst(150 amps)
73 grams
Typical Capacity is between 3000-3100mah www.maxamps.com

now that looks better!

Thanks i didn't read very close!!
live and learn!!

Thats why i'll just wait till all the bugs are worked out!!

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=473 :wave:


Battery Chemistry Polymer Li-Ion
Electrical 3.7V, 6350mAh
Model 7548168
Max Charging Rate 3100mAh (0.5C)
Max Dis-Charging Rate 6300mAh (1C)
Cycle Life Up to 500 Times
Weight 120g
Dimension 169 mm x 49 mm x 8 mm

25.50$

The 1c discharge on a 6300mha pack is 63 amps.

6.3 amp max. discharge rate is no where near high enough.

6.3 amp max. discharge rate is no where near high enough.

exactly!! :thumbsup:

Sorry I misplaced the decimal! lol

But a single cell would be cheaper and you wouldn't have to worry about balancing.


I'm really liking that idea Hank.

What size brushless motor would you run with a 1 cell Lipo to go
about 19t speeds??

Well I am a 1/12th racer that is looking at using a 3 lipo cells in Parallel. Each lipo cell has 1300 mah capacity which would mean a pack of 3900mah capacity. My main point is space in a calandra car. I have a max length to deal with of aprox. 91 mm.

I have narrowed down a few batts that might work. Here is one choice.

http://www.sureflite.com/sureflite/products.php?mc=Batteries%20/%20Chargers&sc=Extreme%20Power%20Lipo&dtl=FB1300XP-2S-WB&offset=0&pid=FB1300XP-2S-WB

Currently as everyone understands the 13.5 in 1/12th on most tracks are just two fast. I was considering using the crawler motor 18.5 with 2 cell lipo. I am sure this would still be two fast.

I like the 1 cell lipo or 2-3 cell Parallel option. Obviously a 1 cell with capacity of 3000 mah's and a size of less than 90 mm in length is what I need.

JimmyJon



Ps: this sounds silly but could someone teach me how to post picture of car on this thread?

I'm really liking that idea Hank.

What size brushless motor would you run with a 1 cell Lipo to go
about 19t speeds??
IT WOULD TAKE ABOUT A 4.5-6.5 BRUSHLESS MOTOR

JimmyJon- This (http://www.hobbytalk.com/bbs1/faq.php?faq=vb_read_and_post#faq_vb_attachment_exp lain) is the probably the easiest. Of course you would have to save the picture to your computer first. Put your curser on the picture and right click, choose the "save image as" option from the drop down menu and do what it says. If you have any problems, email me:gezer2u@hotmail.com

There seems to be more intrest in LiPo's for 12th lately.

I've actually run both single cell and 2 cell voltage with two modified MaxAmps receiver packs. It's about 5000 mAh for single cell voltage and half that for 2 cell voltage.

Single cell is pretty slow and it's all about set-up and driving the absolute shortest line. Also, if you run mod, it takes a 3.5 turn to get to where a 5.5 is on 4 NiMh cells. Even with the 3.5 you can drive hard for 8 minutes without dumping. A 13.5 on single cell voltage was significantly slower than brushed stock on the straight but had a ton of punch on the infield.

2 cell LiPo is pretty fast but not as fast as you'd think. I ran a 5.5 motor and it was actually about the same laptimes as a 4.5 with NiMh. The nice thing about 2 cell voltage is that the capacity is low enough to dump in 8 minutes with mod. This brings some strategy and throttle control back into racing.

Fred -

did you add weight to car to compensate for lightness?

Ok what about charging......to charge lets say the pack list above ( single cell voltage 3 cell 3900mah). Just use same charger and set to what amps. 1.3 amps?

would this be enough to run 8 minutes with the 3.5 or 4.5? also would the pack handle the amp draw??

thanks

the only reason that I added weight was to make the car handle better. With such a light pack, it moves a ton of weight bias foreword in the car.

I added some weight that I had in my box just behind the battery (I think 1 ounce total).

For charging, I used a Ice charger. Just set it to the number of cells that I had and went from there. I charged at 5 amps for everything but I would caution that it's probably not so good if you run at 2 cell voltage.

Single cell voltage charge at 1C would be 6 amps (12cells x .5 amp). It would be half that for 2 cell but mine was fine at 5.

Almost forgot, single cell voltage has plenty of runtime to use a 3.5 turn for 8 minutes. 2 cell would probably limit you to a 6.5 or so depending on your set-up and driving skills.

At 10c my pack can handle 60+ amps continuous for single cell voltage and 30+ amps continuous for 2 cell voltage. The surge currents can be much higher than the continuous rating (I think 15C for the cells I have).

In any case, the cells aren't hot after the run and were only slightly warm at most for all of the motors that I ran.

Fred-

I kind of find it funny that some places require a Lipo Sack for charging and storage for Lipo's to be allowed to race. After all isn't the IB cells blowing up.

I have been using Lipo's for sometime now and find them very reliable and no failures. I guess there is risk in everything we do however is there more risk if lipo's are involved?

At this point I would say NO.

Would be kind of interesting lets say a big race like the INdoorchamps would come out and say yes to Lipo's in 1/12th. Lets just keep the rule very simple. In mod 1/12th single cell voltage with any capacity and any cell count as long as you make weight.

In 19 turn/ stock 1/12th no weight limit, single cell voltage, any cell count.

Everything must have a 20 rating or higher. Must disclose if you are using Lipo's with race organizer at beginning of event and proof the 20C requirement.


I don't think a lipo single voltage car could win in 1/12th stock or 19 turn but in Mod it could be intersting.

This would also bring attention to some Mfg'ers maybe enough to sponsor a class.

Just a thought???

I agree that the NiMh cells are becoming more of a safety issue lately. LiPo is becoming less of a safety issue.

As much as I'd like to see LiPo racing in 12th at big races, they wouldn't be compeditive in any of the classes at single cell voltage. This is based on the little bit of testing that I've done so far.

In order to make this a useful change I think there needs to be a significant weight allowance for the LiPo cars. Just based on the little bit of testing that I've done you need the weight savings to take advantage of the LiPo packs.

From my testing, single cell LiPo is still not compeditive compared to 4 cell at single cell voltage. With 2 cell voltage that would be a different story.

There are several things that need to be figured out before we all take the plunge into LiPo 12th cars:

1) Standard max cell size and pack volume to control capacity.
2) Cell protection (some kind of protective wrap or case)
3) Cell voltage (single cell, 2 cell, any?)
4) Cell approval and test requirements. (Are the standard industrial tests enough?)
5) LiPo car weight break (similar to the weight save that ROAR has for 4-5-6 cell sedan)

Fred-

1) currently capacity with regular cells has become less of issue. I see this as a non-issue. If you had to put a number to it just use the MAH we currently have.

2) I see the reason for a hard -case. Curently no offers this in a length similar to 4-cell size (96mm length X width of sub c). How about I go back in our shop. Have the CAD guy draw up a molded case that fits into the slots of 4 cell holes of chassis just like the orion pack (except what about tee bar cars). Design it with a removable top and add fuse. Have ROAR approve the case (you know how fast theymove). Now as long as the soft lipo bat fits inside and its seeled. #3 Wire for single cell application. and go run. Would this be any harder than building your own 4 cell pack? No...

4) what is the standard for cell aproval. Lets see...... Somebody becomes a dist.. They send in the cell they want approved. The shrink wrape states 4200 MAH. They place cell on charger/discharger. They may cycle. OK approved!! Samething could apply. My feeling is stick with single cell voltage and as long as MFG. has a 15c rating or higher and fits in case then your good.

5) since single cell is at a disadvantage then give to advantage back (weight) as incentive to run lipo.

These are just some thoughts to at least explore the possibilites. It sure would be nice to have another alternative to what we currently have even at the disadvantage of voltage.

Fred-

1) currently capacity with regular cells has become less of issue. I see this as a non-issue. If you had to put a number to it just use the MAH we currently have.

2) I see the reason for a hard -case. Curently no offers this in a length similar to 4-cell size (96mm length X width of sub c). How about I go back in our shop. Have the CAD guy draw up a molded case that fits into the slots of 4 cell holes of chassis just like the orion pack (except what about tee bar cars). Design it with a removable top and add fuse. Have ROAR approve the case (you know how fast theymove). Now as long as the soft lipo bat fits inside and its seeled. #3 Wire for single cell application. and go run. Would this be any harder than building your own 4 cell pack? No...

4) what is the standard for cell aproval. Lets see...... Somebody becomes a dist.. They send in the cell they want approved. The shrink wrape states 4200 MAH. They place cell on charger/discharger. They may cycle. OK approved!! Samething could apply. My feeling is stick with single cell voltage and as long as MFG. has a 15c rating or higher and fits in case then your good.

5) since single cell is at a disadvantage then give to advantage back (weight) as incentive to run lipo.

These are just some thoughts to at least explore the possibilites. It sure would be nice to have another alternative to what we currently have even at the disadvantage of voltage.

1) the current capacity IS an issue in mod. Look at all the dumpers in the IIC at Vegas. Add to that a lower voltage and you'll pull more current to make the same power. This makes the capacity even more of an issue. I'm not saying that this ia a bad thing per say but the capacity of a LiPo pack can be controlled much more tightly than a NiMh. It should be controlled.

2) The whole hard case thing is a joke and gives a false sense of security. A lexan hard case (Carbon 3200) can dent in a crash just like your car body. It can and probably will rebound back out hiding the dammage to the cells. What we need is some protection for the cells and reasonable testing to show that impact failures aren't a problem.

4) The current ROAR battery approval process is not good enough. I personally can start "company X" and submit my own cells from China. The custom shrink on the cells doesn't cost much more. There are absolutely no safety guidelines for cells that are submitted. This area must be improved in the process. The manufacturers should be required to submit the cell manufacturer (for ROAR's eyes only) and the cell's safety data. This would include the standard overcharge and "nail" tests but be upgraded for RC. Overcharge would be at power supply voltage to simulate a blown charger and there should be a "dent" or "crush" test added to simulate crash dammage.

5) Single cell voltage would not be compeditive in stock and 19 turn regardless of the weight. The cars work like crap with LiPo cells because it really screws up the weight distribution.

Fred I am on same page as you but I am sure you realize it would take an extreme effort from someone to make all this issues work. ROAR is all we really have and I am sure they would botch this up as usual.

Actually, lower voltage means lower amp draw. It's a fact of ohms law.

Actually, lower voltage means lower amp draw. It's a fact of ohms law.
Hank - That's only true IF you don't change the gearing or the motor. What the oval crowd has learned (the hard way) when they switched to 4 cells is that you then raise the gearing to try to regain the lost speed, or run hotter motors in mod class (can you say 6-turn?), and the amp draw goes up and battery life goes down. Same thing that will happen if 5-cell takes over in touring cars.

Really, if the goal is to speed things down, why not go to a 6V Lead-gel cell. I got a 2 Million cadle power flashlight from BassPro and that is what came with light. Not bad for $14.99 The cells weighs like a 6pack, but rated for 2.5AH. I am sure some China company can make these batteries for about the cost of ONE IB4200.

Kevin's correct, it's harder on the batteries. Probably worse for NiMh than LiPo because of the difference in IR between the two.

Don't think ohms law for the lower voltage, think Power in watts. P=VI or voltage times current = power. You gear up to make the same power on less voltage (to a point).

There's all kinda of other stuff that happens on lower voltage high wind brushless stuff. At times, the motor timing can be criticacal for performance.

You can not make the same power on one cell that you can on 2 cells. A motor can only make so much power. If your amp draw on one cell is higher then it is on 2 cells, then your 2 cell setup is wrong.