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Old 08-09-2007, 09:19 AM
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Cain
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I am interested in trying some of these packs. Few questions with answers from A123 Support!

1. Has anyone successfully mounted the 4600 4 cell pack (6.6V right?) in an RC10T4 and an RC10B4? Pics please!

I have not seen photos of the battery mounted into an RC10 but where there is a will there is a way. I have a XXXT that is a similar design. I used a dremel tool to bring the battery holder side walls down and then used velcro straps to keep it in place.

2. The Battery packs can only be charged with the A123 charger?

The battery packs can only be charged with an A123 compatible charger. There are others besides ours (Xtrema, FMA, Orbit, Bantam, etc. However if you don't have one of these our charger is the best bang for your buck. 10A charger, with Balancing, for $100.

3. How has the performance been at 6.6V versus a 7.2V Nimh pack?

The performance VS. a NiMH pack is: The pack put into the vehicle will be lighter (~20%) the acceleration will be better. You will need to change your pinion gear to make good use of our high amperage capabilities, or you can use the turbo module. Faster charge time 4600mAh charges in 30 minutes, and should run for about 20 minutes.


4. How has the performance been at 6.6V versus a 7.4V Lipo pack?

The performance VS a LiPo pack: The pack is slightly heavier than the LiPo. Again you will have to change the pinion to get the speed up or use the turbo. The benefits are the 30 minute charge time, If you crash the likely hood of damaging the pack is much much less. The pack will last 5X longer (cycles) then the LiPo. The need to monitor the Low voltage cutoff is not necessary.

5. What makes these safer than the LI-MN technology that Apogee sells?


Apogees Lithium Manganese is “Safer” then LiPo (cobalt oxide) but it is not 100% safe. It still gives up oxygen under abuse and can still catch fire. Though they can Drill a hole in it with a Drill (while holding it in their hand). If you look at that video closely you can see the inside Glowing orange.

6. What are some of the storage and maintanence things you need to do with these packs?

These batteries have a great shelf life they loose approximately 3% per month. They can be stored for over a year with out any problems (for long term storage beyond 3 months they should be charged to 100%, short term storage should be greater than 50%. They should not be stored longer than a month if they are discharged.

7. Do you need to set a low voltage cutoff on these packs? If so, what have you been setting them at on say a Mamba Max speed control?

To elaborate on the statement in #4. We recommend a cut off voltage of 2.0V / cell. In most vehicles they can be run until performance drops off. You will notice that you get full performance during the entire discharge and then all at once it will die (in about 10 seconds). Once this happens you should stop running it. I have run it until the vehicle would no longer drive, this is ok to do now and then but you should pull the battery once the performance changes. Usage of a LiPo in this way would seriously reduce the cycle life of the pack if not immediately damaging it.

8. The Al123 Turbo Module, using say at most a Mamba Max 7700 unit, has there been any current problems with the battery packs when you up them to 7.2V ?


The turbo module solution was designed before brushless motors were the Hot New thing. It was designed to offer super performance on Brushed motors but does not have the power handling capabilities for a motor like the 7700. If you really wanted to make that thing scream you could set it up with a 3S pack (there are people running this setup in XXXTs, stampedes, and rustlers. Though Check with Castle before doing this, they don't recommend a 3S LiPo but our 3S is a bit lower voltage.

9. Are there any cell sizes they make that would work in a 1/18 scale vehicle?

We are preparing for release a new pack that would be applicable to the 18th scale market. It should be available in a few months. (Hopefully before Christmas).

10. With the 4600 pack on a brushless 5700 setup in a stadium truck of buggy, 2wd, what has been the average run times you are seeing?

Your runtime would be in the neighborhood of 17-22 minutes depending on your driving style. I get 8-9min with my XXXT and a mamba 6900.

11. After a run, how long do you need to let the cells cool before charging them?

The rule for charging our batteries is “ If you can hold it in your hand then you can charge it ” . There are very few applications where the battery would get hot enough during a run that you would need to wait to charge it. The batteries do not get hot during charge so they typically cool down while charging.

Last edited by Cain; 08-11-2007 at 07:39 AM.
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