A123Racing Battery Questions  
View related threads: (in this forum | in all forums)

Tower Hobbies
Enter up to 4 keywords or Tower stock numbers
Logged in as Guest



Users viewing this topic: none
  Printable Version
       



All Forums >> Radios, Batteries, Clubhouse and more >> Batteries & Chargers >> A123Racing Support >> A123Racing Battery Questions
Page: [1] 2 3 4 5 6 7 8 9 10   next >   >>  

Login
Message << Older Topic   Newer Topic >>
A123Racing Battery Questions - 8/25/2006 3:36:55 PM   
A123 Racing


 

Posts: 101
Joined: 8/25/2006
From: Hopkinton, MA, USA
Status: offline 		Hello RC Universe, please use this forum for any questions regarding the battery packs, RC developer cells, or our technology in general.

Brian


       Post #: 1

RE: A123Racing Battery Questions - 8/30/2006 7:15:36 PM   
A123 Racing


 

Posts: 101
Joined: 8/25/2006
From: Hopkinton, MA, USA
Status: offline
quote:

Brian,

Your batteries seem to operate at a slightly lower voltage than conventional Lithium Poly batteries? I assume that the mandatory cut-off voltage is also lower. What is it? If I am configuring a system for aircraft operation that would normally be 6S, do I need to add a cell to work with your system?

Bob


Hello Bob,

We recommend a 2.0V / cell cutoff, though our cells are extremely tolerant of over voltage and undervoltage. 1.0V/cell will not be a problem as long as the load is not kept for an extended period of time. As far as needing to add a 7th cell to replace your 6S configuration; that depends alot on your setup. I know some people are using our batteries at the lower voltage and simply changing to a larger prop to make better use of our high power capabilities. For example; someone using a Thunderpower Lipo was running an 11 x 8 prop at 30 amps, after using our batteries he changed to a 14 x 8 prop at 43 amps with spectacular results. But again it depends on your individual setup.

Brian


(in reply to A123 Racing)
       Post #: 2

RE: A123Racing Battery Questions - 8/31/2006 7:10:56 PM   
Thundermaxx1


 

Posts: 2
Joined: 8/30/2006
From: Wellford, SC, USA
Status: offline 		I might be missing something but do these batteries not have an internal cut off like others?

(in reply to A123 Racing)
       Post #: 3

RE: A123Racing Battery Questions - 9/2/2006 1:08:09 AM   
DougE


 

Posts: 12
Joined: 6/6/2006
From: roseville, AB, USA
Status: offline 		Hi A123, thinking of buying a 2s2p-2 system for my losi truck and b4 buggy. Running novak systems now, the GTB / velociti with 4.5 is in the losi. Will your battery work with the novaks?

Also, thinking of getting a mamba max--will your battery system work with them?

(in reply to Thundermaxx1)
       Post #: 4

RE: A123Racing Battery Questions - 9/5/2006 3:51:43 AM   
Lee Jay


 

Posts: 11
Joined: 7/9/2006
From: Westminster, CO, USA
Status: offline 		Hello. I've been following your company's development for quite a while now.

Current limitations appear to be:

- Lower energy density than Lithium Polymer batteries (~100 Wh/kg versus ~140 Wh/kg). This is a very important consideration for aircraft.

- Only one available cell size (2300mAh). LiPos seem to be available from 300mAh to 5000mAh with numerous options in between.

- Can't charge using regular LiPo chargers
I mention this on because I'm interested in the CellPro from FMA because it charges all the cells separatly - a very nice advantage in my opinion.

- Limited pack availability (2S1P, 3S1P, 2S2P).

The advantages of inherant safety, increased durability and higher charge/discharge rates are attractive.

Can you comment on how you plan to address each of the four limitations I mentioned above please?

Thank you.

Lee Jay

(in reply to A123 Racing)
       Post #: 5

RE: A123Racing Battery Questions - 9/7/2006 2:01:08 AM   
Nightshift


 

Posts: 12
Joined: 3/2/2006
From: , QC, CHILE
Status: offline 		Hi A123!
I have been reading at your new thecnologie for a while on this forum and on a other forum to.
i got a associated T4 that is equiped with a LRP sphere esc that i run with a neo one 1 star (Brushless system)
I use to power that with some 7.2v NHIM 3800 battery pack from POLE POSITION.
This summer i sold most of my pack because i wont to switch to a better thecnologie for next winter racing.
I was thinking of LIPO or LIMG until i heard about you.
I got no lipo charger . so it gone a be a fresh start for the next thecnologie.
We run 5 minutes race off road dirt track.
what do you suggest for a complete set up .
I used to have 8 packs for my racing day : 4 for practice and set up the car
1 for each qualif. (3) and my best one for the final (1) total of 8.

Nightshift

(in reply to Lee Jay)
       Post #: 6

RE: A123Racing Battery Questions - 9/11/2006 3:44:10 AM   
Batfish


 

Posts: 17
Joined: 6/13/2004
From: Worcester, MA, USA
Status: offline
quote:

ORIGINAL: DougE

Hi A123, thinking of buying a 2s2p-2 system for my losi truck and b4 buggy. Running novak systems now, the GTB / velociti with 4.5 is in the losi. Will your battery work with the novaks?

Also, thinking of getting a mamba max--will your battery system work with them?


DougE,

I've been using the A123Racing packs for a couple months now, and working with Brian (in helping them get real-world information) for just as long.

I just ran my XXX-T MF with the Novak GTB/5.5 and an A123Racing 2s1p 2300 pack at RCCA's Battery Blast in CT yesterday. I took 3rd in the B Main (I'm not a sponsored mega-driver ) and had zero issues with the batteries. In general, I've found that increasing your pinion size by 2 teeth (in 48p) makes the 2s1p 2300 work like a normal 6-cell nimh pack.
My MF had no problems keeping up with any of the hot setups yesterday - it was only my driving skill that kept the truck back

I've also used the 2s1p 2300 pack in my TC3 "O" (buggy conversion for the TC3) with a Novak SS5800, to the same effect. Bump up a couple teeth and it'll be as fast as a 6-cell nimh, with exceptional punch and stable power throughout the entire run.

I got at least 6 minutes (5-minute quals and main, plus practice laps) from the A123Racing 2s1p packs in my XXX-T MF with the Novak GTB/5.5 yesterday. Neither the packs, nor the motor, nor the ESC heated up at all in 80F weather.
In my TC3 "O", I get around 9 solid minutes of running on the track before the batteries dump. That is with the Novak SS5800 setup.

I also use the A123Racing 2s2p 4600 packs in my G-Maxx (E-Maxx with a GorillaMaxx chassis), wired in series. I use a BK 9920 speed controller with a Lehner 1940/9 motor and get about 15 minutes of run time on the track.


_____________________________

______________
Joe

(in reply to DougE)
       Post #: 7

RE: A123Racing Battery Questions - 9/11/2006 3:57:41 AM   
Batfish


 

Posts: 17
Joined: 6/13/2004
From: Worcester, MA, USA
Status: offline
quote:

ORIGINAL: Nightshift

Hi A123!
I have been reading at your new thecnologie for a while on this forum and on a other forum to.
i got a associated T4 that is equiped with a LRP sphere esc that i run with a neo one 1 star (Brushless system)
I use to power that with some 7.2v NHIM 3800 battery pack from POLE POSITION.
This summer i sold most of my pack because i wont to switch to a better thecnologie for next winter racing.
I was thinking of LIPO or LIMG until i heard about you.
I got no lipo charger . so it gone a be a fresh start for the next thecnologie.
We run 5 minutes race off road dirt track.
what do you suggest for a complete set up .
I used to have 8 packs for my racing day : 4 for practice and set up the car
1 for each qualif. (3) and my best one for the final (1) total of 8.

Nightshift



Nightshift,

I'd recommend two of the 2s1p 2300 packs.
They will give you the same performance - no more worrying about which pack is the "best" pack.
As with other Lithium technologies, these batteries have an extremely low self-discharge rate so you don't have to worry about peaking them right before racing. You can even charge them a couple days before the race and not notice any decrease in the battery's performance.
The A123Racing packs also shouldn't heat up during a 5-minute race, and can be put directly onto the Hypersonic charger to be freshly charged again in about 10-15 minutes. If they happen to get a little warm, you may want to let them cool for a few minutes before charging them.
You can always have one pack charged while using the other, so you should never be out of business.

_____________________________

______________
Joe

(in reply to Nightshift)
       Post #: 8

RE: A123Racing Battery Questions - 9/12/2006 2:36:49 AM   
A123 Racing


 

Posts: 101
Joined: 8/25/2006
From: Hopkinton, MA, USA
Status: offline 		Hello People,

I've got more answers to your questions.

Thundermaxx, do these batteries not have an internal cutoff like others?

Low voltage cutoff should not be of great concern to the average user. We recommend a cut-off voltage of 2V / cell but they are tolerant of over and under voltage. The working range for the cells is: Charge to 3.6V / cell and discharge to 2.0V/cell. The tolerable range is 4.2V to 1.0V / cell. These characteristics can be applied to the packs as long as the individual cells in the pack remain balanced. For example a 2S1P (6.6V) pack can be brought up to 8.4V provided that it is not kept at that voltage for a long duration of time, and that the pack is balanced properly. If the cells in the pack were not balanced you could seriously damage your pack at 8.4V. If one of the cells was measuring 3.6V the other would be at 4.8V. In this situation it is certain that you would shorten the life of the pack, and very possible that you would permanently damage it. Even though the batteries are tolerable of 4.2V / cell we do not recommend that they be charged on a 4.1/4.2V Lithium charger because the charger will maintain the pack voltage at 4.2V for several minutes, which will degrade the life of your pack. Also because those chargers do not monitor and balance the cells during charging it is very possible to permanently damage the pack.

DougE, will your battery work with Novaks now. Also thinking about getting a Mamba Maxx.

Hello DougE, we have people out there running our batteries in their 1/10 scale trucks and cars. I have not heard or seen any problems with them yet. I reviewed the Mamba Maxx manual (available at the manufacturers website) and that should work well also. Please note that the 2S2P battery is a bit larger than a typical NiMH pack that most people are used to. You may need to modify your chassis / battery strap down in order for it to fit. The 2S1P is narrower but still a bit taller than a typical pack, but most people do not have much difficulty in finding a way to keep it in the chassis.

LeeJay, how will we address limitations of our batteries.

Hello LeeJay, because of our single cell size (26mm diameter x 65mm) we limited in some aspects. The solution to this is research and development. We are always looking for the next best thing. Time will be the solution to the limitations you mention. In the mean time we believe that people can certainly make use of the:
Power; 30C continuous 60C pulse.
Safety; No thermal runaway / fire.
Mechanical durability; impact resistant laser welded aluminum canister, and up to 1000 cycles.
Electrical durability, voltage tolerant of 1V to 4.2V / cell.
Quick Charge, As little as 15 minutes with the Sonic Charge system.

The pack availability can be changed based on user feedback. I urge you to let us know if there is something else you are looking for.

Nightshift: Interest in racing A123s

Hello Nightshift, sounds like you have a nice setup there. I am running the sphere with a neo 3 star in my touring car. With a 2S1P battery, and it really moves. Batfish has some great input for your questions. He has been racing these batteries for a little while now. The 2S1P certainly would be the best fit for you. It is small (about 28mm Dia x 132mm) and lightweight (less than half the weight of a NiMH). They charge in about 15 minutes, and I expect you would see run times equivalent to Batfish’s. As long as you don’t require a battery swap sooner than 15 minutes a 2S1P starter kit (2 x 2S1P battery and a charger) should suit you well.

Thanks again for all the questions, please keep them coming.


(in reply to Batfish)
       Post #: 9

RE: A123Racing Battery Questions - 9/12/2006 2:44:59 AM   
Nightshift


 

Posts: 12
Joined: 3/2/2006
From: , QC, CHILE
Status: offline 		Thank. Batfish!
What you suggest to me is about what i was thinking to get to start with for giving them a try.
Just find out to yesterday that they gone run 6 minutes final instead of 5 minutes ,but what i just see in one of your post ,6min. should not be a problem with a 2300ma.

I live in Quebec Canada ,any problem for ordering?

Nightshift.

(in reply to Batfish)
       Post #: 10

RE: A123Racing Battery Questions - 9/12/2006 6:18:44 PM   
A123 Racing


 

Posts: 101
Joined: 8/25/2006
From: Hopkinton, MA, USA
Status: offline 		Hello Nightshift,

We can ship to Canada, however due to the fact that we cannot ship over seas yet we have not set up our website for international orders. I will work this out and let you know once I have a solution.

Brian


(in reply to Nightshift)
       Post #: 11

RE: A123Racing Battery Questions - 9/12/2006 8:32:53 PM   
Lee Jay


 

Posts: 11
Joined: 7/9/2006
From: Westminster, CO, USA
Status: offline
quote:

ORIGINAL: A123 Racing
The pack availability can be changed based on user feedback. I urge you to let us know if there is something else you are looking for.


Thank you for responding.

I think the DeWalt DC9360 is a 10-cell pack of your batteries. Assuming I am correct, and since they sell for about $150 or so street price, it seems to me the cells must be less than $15 each in bulk since an assembled pack should cost more than the individual cells. Your own 2s1p pack is $50 assembled with a connector. I'm sure a significant portion of that price is the cost of assembly and materials beyond the cells themselves.

I've been building my own battery packs for 15 years with no problems. Would you be willing to sell loose cells for something in the $10 range for people like me who don't mind building their own battery packs? In the past, I've bought individual boxes of 20 Sanyo cells for around 10% above the bulk (500 cell) price. Would you be interested in selling boxes (12, 20, whatever you do) for a discount?

Thank you again for being here and responding.

Lee Jay



(in reply to A123 Racing)
       Post #: 12

RE: A123Racing Battery Questions - 9/16/2006 4:52:31 PM   
stanger89


 

Posts: 19
Joined: 7/12/2004
From: Cedar Rapids, IA, USA
Status: offline