PDA

View Full Version : How to charge battery for 25 minutes play?


aphit89
2008.05.01, 09:13 PM
I have sanyo 1000 and I would like charge them with maha MH-C9000 for 25 minutes play...how to charge them corectly? Or do you have any suggestion with any other charger or batteries..thank you

EMU
2008.05.01, 11:01 PM
How much run time do you get with the standard charge rate (1A)? I would think you should get around 20-25 minutes. If you want more, then use a lower charge rate, try 500-700ma. It should take around 2 hours to charge when charging depleted cells. Also, let them trickle for a little after the charge is complete to top them off.

Charging at a lower amperage will slow the car down a little, but give you longer run time.

aphit89
2008.05.02, 01:46 AM
Last time I tried 1A I got run time about 17 minutes.....It still can move forward but hardly to backward...no punch at all

Tjay
2008.05.02, 03:00 AM
discharge battery down to .9v. Then charge it back up with 1 amp. This should give you enough runtime.

You might want to check the following as well:
-make sure do drag on the drive train
-make sure your gear is not too high
-check motor wire for excessive resistance... cut wire strand and such..
-radio setting in not correct

good luck!

EMU
2008.05.02, 11:40 AM
Cycle the battery a few times if it is new. A new cell needs a few cycles before it runs with full capacity.

What motor are you using? Bearings? As Tjay pointed out, you want to make sure that you have little drag on the drivetrain. As that will give you shorter run times.

Are you driving on a track? If you do a lot of dead starts, that will discharge your batteries faster than if you never stop. My 900mah cells give me more than 20 minutes for practice at the local track. I mainly use Speedy 07 motors since they dont have a lot of drag, which allows you to coast a little more entering a corner, using less battery power.

aphit89
2008.05.05, 01:25 AM
I use Xspeed for my motor .....or maybe my batteries still not in full capacity. But I wonder how to set my Helios to make more running time...thank you

aphit89
2008.05.05, 01:26 AM
Yes I play on track and I use Xspeed for my motor .....or maybe my batteries still not in full capacity. But I wonder how to set my Helios to make more running time...thank you

Aurora
2008.05.05, 02:51 AM
I think one little thing that might help is to adjust the throttle Hipoint to lower than the default 100, if you find yourself not using the full throttle most of the time.

But one thing is for sure, previous suggestions of using a lower charge rate will charge the battery more fully (allowing longer runtime), especially when the cells are depleted empty before charge. And all the suggestions are really sound and will be effective when used. :)

EMU
2008.05.05, 11:10 AM
Also, switch to the stock motor, and/or a smaller pinion.

aphit89
2008.05.05, 09:00 PM
Thank you guys for the advices ...very informative but I have one question ...Can Maha charger discharge the cell to .9 V and how to do it?

EMU
2008.05.06, 01:52 AM
To do so with the MH-C9000 when you insert the cells, choose the discharge option, then the discharge amperage. Highest is 1A (1000mA). It will not auto recharge the cells. You would have to do a refresh cycle, which charges, then waits an hour, discharges and waits an hour, then recharges the cell again.

I usually charge the cells in a different charger, and use it primarily as a discharger to sort my cells. I prefer it over the BC-900 since I can discharge the cells at 1A and see how much capacity they had at a higher amperage. The BC-900's cieling for discharge is 500mA. Although the auto recharge to is double what discharge rate you choose. Charging at 1A with this charger on AAA cells without fans causes the cells to overheat, and the temp sensor waits with the charge until the cells cool.

I have 2 LaCrosse BC-900, and 2 Duracell 30 minute chargers. I leave the MH-C9000 at home when I go to the track. I find that I mainly use my Duracell 30min chargers when getting my cells ready for the races. I do my cycling and battery break in at lower amps, just using the higher amps at the races. For me, I buy many batteries and weed out the weaker cells. Only keeping the highest few to run for the races. I typically only use 6 sets of cells for a race night, depending on how many classes I am running.

I use different types of cells in different classes. Some cars I want more punch, some I want less. The 3 main things you control speed with is batteries, fets and motor. The main increase in fets is mainly the ability to run hotter motors, since more amperage can be passed through them. When using a modified motor, you can restrict the flow of power with different batteries.

The Orion 900 for example have a very high output, in stock class they are the fastest cell, and last the duration of the race with ease. In modified class the car is simply too fast with the modified motors.

The BetterPower 1000 cells have a lower output of power, and are decent in stock class, but shine in modified class. The car is much more managable than with the Orions, and the throttle can be fully raised. The car is consistant on power throughout the race. You dont have a super rush in power, but the car is still much faster than stock with Orions.

I like the Duratrax 750's on cars that have a lower amp draw like the 015 with stock motor. They will have good power throughout the race with the stock motors, although with the modified motors, they will taper off. You really have to filter these though, as I had quite a few bad cells straight out the package. They were cheap, and suit the class. I also occasionally run them in Nascar.

I allways try to make my modified feel more like my stock car, and my stock car feel more like my modified car.