A123 Cells Roar??
#1
A123 Cells Roar??
Are these cells roar legal? Their chemistry is safer then lipos & they are already tough and durable.
#2
No cells are legal till they are submitted and pass approval as far as I know.
#3
Unless ROAR rules changes to allow that size of cell, all 26650 cells including the A123's will not be legal.
Resons to Approve the cells:
Safe!!!
Industry accepted size: 26 x 65mm
Industy standards are standards!!! Meaning there will be little chance of this battery disappering or changing sizes. Good news for the racers and car makers.
Great replacement for 5-Cell NiMH
Acceptable compromise for 4-Cell vs. LiPO
Reasons not Approve:
????
???
Obstacles if Approved:
New chassis would have to be designed. But then again new chassis and concepts are always in developement.
Current Price of cells are $12 to $20. Most 1:10 scales would require 4-cells meaning $80 packs. Over time the projected price is to fall to $7 a cell once the market has more diversity of manufacutres. I just bought 10 A123 M1 cells for $8.50 a cell shipped, so the the potential of cheaper prices are there.
1:12 scale pan car...major obstacle!!!
Leave the class as-is 4-cell NiMH or convert to a Lithium battery? If 1:12 converts to a lithium battery I would hope it is a LiFePO4 cell like A123. The voltage increase will not be as great as going to a Li-Po. Then you have the question how many cells and what size? Does 1:12 use 2 or 4 A123 cells. What about soft-cell and the smaller 18650 cells. These are all options for 1:12. More experiementation needs to be done with the 1:12 cars and the A123 batteries.
Resons to Approve the cells:
Safe!!!
Industry accepted size: 26 x 65mm
Industy standards are standards!!! Meaning there will be little chance of this battery disappering or changing sizes. Good news for the racers and car makers.
Great replacement for 5-Cell NiMH
Acceptable compromise for 4-Cell vs. LiPO
Reasons not Approve:
????
???
Obstacles if Approved:
New chassis would have to be designed. But then again new chassis and concepts are always in developement.
Current Price of cells are $12 to $20. Most 1:10 scales would require 4-cells meaning $80 packs. Over time the projected price is to fall to $7 a cell once the market has more diversity of manufacutres. I just bought 10 A123 M1 cells for $8.50 a cell shipped, so the the potential of cheaper prices are there.
1:12 scale pan car...major obstacle!!!
Leave the class as-is 4-cell NiMH or convert to a Lithium battery? If 1:12 converts to a lithium battery I would hope it is a LiFePO4 cell like A123. The voltage increase will not be as great as going to a Li-Po. Then you have the question how many cells and what size? Does 1:12 use 2 or 4 A123 cells. What about soft-cell and the smaller 18650 cells. These are all options for 1:12. More experiementation needs to be done with the 1:12 cars and the A123 batteries.
#4
Tech Master
iTrader: (1)
There is no point making the A123 26650 M1 cell legal. Hardly anybody is using them for 1/10 scale racing applications. Lipo's are nearly interchangeable over NIMh in both size and voltage output. The A123 26650 and A123 18650 are not even close to fitting. Every chassis on the market would have to be redesigned and even if they were redesigned, the traditional power sources (NIMH and LIPO) would not fit right.
The A123 cell in my hand right now measures 26.7mm in diameter and 67mm long (not 26 x 65 as the specs would make you believe). A 2S2P 4 cell pack would be too big to fit properly into any 1/10 scale application.
In addition to size, the votage doesn't match up well even with a 4 cell NIMH. At 20 amps, the A123 will average about 2.8V/cell or 5.6V as a two cell series and slighly more if they are paralleled up (2S2P). A good 5 cell NIMH will average more than 6.4V at 20 amps.
If A123 is legal, they would need their own seperate class and separate chassis. The last thing we need is more racing classes.
I think the perfect application for the A123 cell would be the 1/8 scale electric truggy and buggy chassis - assuming that class takes off as projected. It's a nice big robust cell that is well suited for the bumpy and physically abusive class.
The A123 cell in my hand right now measures 26.7mm in diameter and 67mm long (not 26 x 65 as the specs would make you believe). A 2S2P 4 cell pack would be too big to fit properly into any 1/10 scale application.
In addition to size, the votage doesn't match up well even with a 4 cell NIMH. At 20 amps, the A123 will average about 2.8V/cell or 5.6V as a two cell series and slighly more if they are paralleled up (2S2P). A good 5 cell NIMH will average more than 6.4V at 20 amps.
If A123 is legal, they would need their own seperate class and separate chassis. The last thing we need is more racing classes.
I think the perfect application for the A123 cell would be the 1/8 scale electric truggy and buggy chassis - assuming that class takes off as projected. It's a nice big robust cell that is well suited for the bumpy and physically abusive class.
#5
True. I've heard great things about these cells. They seem perfect for RC.
The aeroplanes guys are getting +200 cycles with zip charging them in 5 minutes with +20A charge. 400 cycles with minimum care seems easy. They also seem to tolerate overcharging and overdischarging better than even the current nimhs.
The voltage thing doesnt seem a problem to me. Everybody in europe is happy wih the current 5 cell rule. Less stress on everything (motor, drivetrain, tires,...) and easier to drive.
Problem is, at 27mm diameter they are really hard to fit in current chassis designs. Most cars are under 24mm
The aeroplanes guys are getting +200 cycles with zip charging them in 5 minutes with +20A charge. 400 cycles with minimum care seems easy. They also seem to tolerate overcharging and overdischarging better than even the current nimhs.
The voltage thing doesnt seem a problem to me. Everybody in europe is happy wih the current 5 cell rule. Less stress on everything (motor, drivetrain, tires,...) and easier to drive.
Problem is, at 27mm diameter they are really hard to fit in current chassis designs. Most cars are under 24mm
Last edited by Itchy; 01-24-2008 at 02:44 AM.
#7
Tech Regular
The A123 cells aren't anything new.
If A123 wants to get into the racing market, they need to release a sub-c sized cell. This would solve a lot of problems with fitment into the cars.
If this "new" technology is so great, then show us a design that actually fits the standard cell size that's used in the RC, automotive and powertool industry. Sub-c cells are still used in powertools, the Toyota Pius (changed from Panasonic to Sanyo last I heard), and RC.
The current A123 cells simply will not fit into a 12th car and unless you have a car that needs a stepladder to get up to the top deck, they won't fit in sedan. The Tc5 might fit these cells but most will not.
If A123 wants to get into the racing market, they need to release a sub-c sized cell. This would solve a lot of problems with fitment into the cars.
If this "new" technology is so great, then show us a design that actually fits the standard cell size that's used in the RC, automotive and powertool industry. Sub-c cells are still used in powertools, the Toyota Pius (changed from Panasonic to Sanyo last I heard), and RC.
The current A123 cells simply will not fit into a 12th car and unless you have a car that needs a stepladder to get up to the top deck, they won't fit in sedan. The Tc5 might fit these cells but most will not.
#8
I have seen tons of people run these cells in cars like the b44. 2 side by side cells is practicly the same size as 3side by side nimh cells. If people believe that using these cells will put you at a disadvantage then I don't see why they shouldn't be allowed since they are much safer & more stable then lipos. I have also seen people easily make a 6minute heat w/ a good 6turn mod using a 1p 2300 mah pack.
#9
#10
#11
Of course people will complain about that too.
So you joining ROAR now or are you going to wait until A123 cells are legal?
#12
Tech Master
iTrader: (65)
a123
The simple point is that there are 2 people on rctech pushing a123 cells. That's it. They both posted in this thread. If you want to run a123 go ahead, but the problem is that a123 are the least compatible with anything else out there. At least lipo and nimh voltages are close together. There is no reason at all to have a123 unless you run them in an open class where anything goes, and if that's the case, have fun using them.
#13
As mentioned, A123 needs to make a subc size cell if they are serious about the r/c market. Then we could talk about it seriously.
I have a few A123 cells too, but never got them with 1/10 in mind... they are a good alternative for stuff like bashing and 1/8 conversions etc.
I have a few A123 cells too, but never got them with 1/10 in mind... they are a good alternative for stuff like bashing and 1/8 conversions etc.
#14